• Re: How laser rangefinder or laser distance meter work and what chip ca

    From a a@21:1/5 to a a on Fri Aug 12 03:23:53 2022
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    notjhing found on the internet

    https://en.wikipedia.org/wiki/Time_of_flight

    https://www.fullyinstrumented.com/how-a-laser-measure-works/

    https://sciencing.com/ultrasonic-sensors-work-4947693.html
    "The computer chip in the LRF uses a high-speed digital clock to calculate the time taken to hit the target.

    what is an operating frequency of the clock in LRF ?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to a a on Fri Aug 12 06:46:07 2022
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    GHz ASIC
    3E-9 second per meter

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From TTman@21:1/5 to Ed Lee on Fri Aug 12 17:06:33 2022
    On 12/08/2022 14:46, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    GHz ASIC
    3E-9 second per meter


    FPGA...I worked on one...


    --
    This email has been checked for viruses by Avast antivirus software. www.avast.com

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ricky@21:1/5 to TTman on Fri Aug 12 09:48:17 2022
    On Friday, August 12, 2022 at 12:06:42 PM UTC-4, TTman wrote:
    On 12/08/2022 14:46, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    GHz ASIC
    3E-9 second per meter


    FPGA...I worked on one...

    I have one of the laser devices. It measures to a fraction of an inch. That would be an equivalent frequency of maybe 100 GHz which is a bit difficult, even inside an FPGA. Does this require multiple inputs with varying delays to define timing to a
    finer resolution than the clock period?

    --

    Rick C.

    - Get 1,000 miles of free Supercharging
    - Tesla referral code - https://ts.la/richard11209

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From a a@21:1/5 to Ed Lee on Fri Aug 12 11:45:14 2022
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From a a@21:1/5 to Ricky on Fri Aug 12 11:49:00 2022
    On Friday, 12 August 2022 at 18:48:21 UTC+2, Ricky wrote:
    On Friday, August 12, 2022 at 12:06:42 PM UTC-4, TTman wrote:
    On 12/08/2022 14:46, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    GHz ASIC
    3E-9 second per meter


    FPGA...I worked on one...
    I have one of the laser devices. It measures to a fraction of an inch. That would be an equivalent frequency of maybe 100 GHz which is a bit difficult, even inside an FPGA. Does this require multiple inputs with varying delays to define timing to a
    finer resolution than the clock period?

    --

    Rick C.

    - Get 1,000 miles of free Supercharging
    - Tesla referral code - https://ts.la/richard11209
    thank you Ricky
    since iPhone claims Lidar in smartphone and parallel distance array calculation on-the-fly

    For 1cm resolution 10 GHz single point
    turns into 100 x 100 x 10 GHz clock frequency
    for 100 points x 100 points array

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to TTman on Fri Aug 12 12:31:30 2022
    On Friday, August 12, 2022 at 9:06:42 AM UTC-7, TTman wrote:
    On 12/08/2022 14:46, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    GHz ASIC
    3E-9 second per meter


    FPGA...I worked on one...

    Too slow. I have only seen a few hundred MHz FPGA.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to a a on Fri Aug 12 12:55:22 2022
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?

    There is no point in measuring all 10,000 points all at once.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From a a@21:1/5 to Ed Lee on Fri Aug 12 13:06:31 2022
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to a a on Fri Aug 12 13:37:24 2022
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved

    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to a a on Fri Aug 12 14:58:07 2022
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation

    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From a a@21:1/5 to Ed Lee on Fri Aug 12 14:31:27 2022
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From a a@21:1/5 to Ed Lee on Fri Aug 12 15:40:34 2022
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to a a on Fri Aug 12 16:10:03 2022
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    3GHz (reasonable clock) for 10cm resolution.

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    https://en.wikipedia.org/wiki/Oversampling
    for higher resolution.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Anthony William Sloman@21:1/5 to Ed Lee on Fri Aug 12 17:52:17 2022
    On Saturday, August 13, 2022 at 9:10:07 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:

    <snipped uninformed comment>

    https://en.wikipedia.org/wiki/Tellurometer

    was the original wavelength-based range-finder, and it didn't send out a pulse and measure the time until it returned.

    Measuring the phase shift along the path to the reflector and back is a more practical scheme.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to bill....@ieee.org on Fri Aug 12 18:00:42 2022
    On Friday, August 12, 2022 at 5:52:21 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 9:10:07 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    <snipped uninformed comment>

    Yes, we should.


    https://en.wikipedia.org/wiki/Tellurometer

    was the original wavelength-based range-finder, and it didn't send out a pulse and measure the time until it returned.

    Measuring the phase shift along the path to the reflector and back is a more practical scheme.

    This is talking about microwave. We are talking about lightwave (laser).

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Anthony William Sloman@21:1/5 to Ed Lee on Fri Aug 12 18:12:53 2022
    On Saturday, August 13, 2022 at 11:00:46 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 5:52:21 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 9:10:07 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    <snipped uninformed comment>
    Yes, we should.

    https://en.wikipedia.org/wiki/Tellurometer

    was the original wavelength-based range-finder, and it didn't send out a pulse and measure the time until it returned.

    Measuring the phase shift along the path to the reflector and back is a more practical scheme.

    This is talking about microwave. We are talking about lightwave (laser).

    Both are electromagnetic waves and phase shift works for both. HP's laser interferomenter certainly measured to small fractions of the helium-neon laser wavelength (which I used to know to ten significant digits when we were designing one in).

    The bottom of the Tellurometer page offers a link to a page on laser rangefinders. I haven't clicked on it in years. Maybe you should.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to bill....@ieee.org on Fri Aug 12 18:19:37 2022
    On Friday, August 12, 2022 at 6:12:58 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 11:00:46 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 5:52:21 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 9:10:07 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    <snipped uninformed comment>
    Yes, we should.

    https://en.wikipedia.org/wiki/Tellurometer

    was the original wavelength-based range-finder, and it didn't send out a pulse and measure the time until it returned.

    Measuring the phase shift along the path to the reflector and back is a more practical scheme.

    This is talking about microwave. We are talking about lightwave (laser).
    Both are electromagnetic waves and phase shift works for both. HP's laser interferomenter certainly measured to small fractions of the helium-neon laser wavelength (which I used to know to ten significant digits when we were designing one in).

    The difference is the much higher frequencies of lightwave vs. microwave.

    The bottom of the Tellurometer page offers a link to a page on laser rangefinders. I haven't clicked on it in years. Maybe you should.

    Yes, you should listen to your own advice:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Anthony William Sloman@21:1/5 to Ed Lee on Fri Aug 12 18:50:54 2022
    On Saturday, August 13, 2022 at 11:19:41 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 6:12:58 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 11:00:46 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 5:52:21 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 9:10:07 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    <snipped uninformed comment>
    Yes, we should.

    https://en.wikipedia.org/wiki/Tellurometer

    was the original wavelength-based range-finder, and it didn't send out a pulse and measure the time until it returned.

    Measuring the phase shift along the path to the reflector and back is a more practical scheme.

    This is talking about microwave. We are talking about lightwave (laser).
    Both are electromagnetic waves and phase shift works for both. HP's laser interferomenter certainly measured to small fractions of the helium-neon laser wavelength (which I used to know to ten significant digits when we were designing one in).
    The difference is the much higher frequencies of lightwave vs. microwave.
    The bottom of the Tellurometer page offers a link to a page on laser rangefinders. I haven't clicked on it in years. Maybe you should.

    Yes, you should listen to your own advice:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder

    It isn't all that accurate. The other techniques can do better, but they do tend to be more expensive, as more accurate instruments can afford to be.

    "Multiple frequency phase-shift - this measures the phase shift of multiple frequencies on reflection then solves some simultaneous equations to give a final measure.

    Interferometry - the most accurate and most useful technique for measuring changes in distance rather than absolute distances."

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From whit3rd@21:1/5 to Ed Lee on Fri Aug 12 18:57:12 2022
    On Friday, August 12, 2022 at 6:19:41 PM UTC-7, Ed Lee wrote:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder

    Yeah, for rangefinding the corner-cube reflector left on Luna, that simple scheme's workable. For shorter
    distances, though, modulation of an FM burst, and detection of the interference of outgoing
    and incoming to generate the difference frequency, is the most practical way of doing it.

    I'm pretty sure my Hot Wheels radar gun isn't "measuring the time" with a digital clock, directly.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to All on Fri Aug 12 19:01:54 2022
    On Friday, August 12, 2022 at 6:57:16 PM UTC-7, whit3rd wrote:
    On Friday, August 12, 2022 at 6:19:41 PM UTC-7, Ed Lee wrote:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder
    Yeah, for rangefinding the corner-cube reflector left on Luna, that simple scheme's workable. For shorter
    distances, though, modulation of an FM burst, and detection of the interference of outgoing
    and incoming to generate the difference frequency, is the most practical way of doing it.

    I'm pretty sure my Hot Wheels radar gun isn't "measuring the time" with a digital clock, directly.

    Yes, Bill and you are bring up all possible ways to measure distance. But OP specifically asked for digital processing of laser range-finder.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From whit3rd@21:1/5 to Ed Lee on Fri Aug 12 19:30:44 2022
    On Friday, August 12, 2022 at 7:01:58 PM UTC-7, Ed Lee wrote:
    On Friday, August 12, 2022 at 6:57:16 PM UTC-7, whit3rd wrote:
    On Friday, August 12, 2022 at 6:19:41 PM UTC-7, Ed Lee wrote:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder
    Yeah, for rangefinding the corner-cube reflector left on Luna, that simple scheme's workable. For shorter
    distances, though, modulation of an FM burst, and detection of the interference of outgoing
    and incoming to generate the difference frequency, is the most practical way of doing it.

    I'm pretty sure my Hot Wheels radar gun isn't "measuring the time" with a digital clock, directly.
    Yes, Bill and you are bring up all possible ways to measure distance. But OP specifically asked for digital processing of laser range-finder.

    Do you have an objection? A "laser range finder" is a broad class of instruments, with no particular
    'digital processing' specificity, and digital processing is not, in the general case, superior
    or practical in the pulse/clock-and-count scenario, so we discuss others.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Anthony William Sloman@21:1/5 to Ed Lee on Fri Aug 12 19:37:08 2022
    On Saturday, August 13, 2022 at 12:01:58 PM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 6:57:16 PM UTC-7, whit3rd wrote:
    On Friday, August 12, 2022 at 6:19:41 PM UTC-7, Ed Lee wrote:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder
    Yeah, for rangefinding the corner-cube reflector left on Luna, that simple scheme's workable. For shorter
    distances, though, modulation of an FM burst, and detection of the interference of outgoing
    and incoming to generate the difference frequency, is the most practical way of doing it.

    I'm pretty sure my Hot Wheels radar gun isn't "measuring the time" with a digital clock, directly.

    Yes, Bill and you are bring up all possible ways to measure distance. But OP specifically asked for digital processing of laser range-finder.

    But the OP is a a, and he's time-wasting half-wit. Nobody sane is going to spend time on responding to him. You are the sucker who did.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to All on Fri Aug 12 19:37:20 2022
    On Friday, August 12, 2022 at 7:30:48 PM UTC-7, whit3rd wrote:
    On Friday, August 12, 2022 at 7:01:58 PM UTC-7, Ed Lee wrote:
    On Friday, August 12, 2022 at 6:57:16 PM UTC-7, whit3rd wrote:
    On Friday, August 12, 2022 at 6:19:41 PM UTC-7, Ed Lee wrote:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder
    Yeah, for rangefinding the corner-cube reflector left on Luna, that simple scheme's workable. For shorter
    distances, though, modulation of an FM burst, and detection of the interference of outgoing
    and incoming to generate the difference frequency, is the most practical way of doing it.

    I'm pretty sure my Hot Wheels radar gun isn't "measuring the time" with a digital clock, directly.
    Yes, Bill and you are bring up all possible ways to measure distance. But OP specifically asked for digital processing of laser range-finder.
    Do you have an objection? A "laser range finder" is a broad class of instruments, with no particular
    'digital processing' specificity, and digital processing is not, in the general case, superior
    or practical in the pulse/clock-and-count scenario, so we discuss others.

    I am just responding to OP direct question of:
    "what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?"

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to bill....@ieee.org on Fri Aug 12 19:39:09 2022
    On Friday, August 12, 2022 at 7:37:13 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 12:01:58 PM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 6:57:16 PM UTC-7, whit3rd wrote:
    On Friday, August 12, 2022 at 6:19:41 PM UTC-7, Ed Lee wrote:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder
    Yeah, for rangefinding the corner-cube reflector left on Luna, that simple scheme's workable. For shorter
    distances, though, modulation of an FM burst, and detection of the interference of outgoing
    and incoming to generate the difference frequency, is the most practical way of doing it.

    I'm pretty sure my Hot Wheels radar gun isn't "measuring the time" with a digital clock, directly.

    Yes, Bill and you are bring up all possible ways to measure distance. But OP specifically asked for digital processing of laser range-finder.
    But the OP is a a, and he's time-wasting half-wit. Nobody sane is going to spend time on responding to him. You are the sucker who did.

    It's a rare on-topic case related to electronics and worth answering.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Mike Monett@21:1/5 to whit3rd@gmail.com on Sat Aug 13 04:10:12 2022
    whit3rd <whit3rd@gmail.com> wrote:

    On Friday, August 12, 2022 at 6:19:41 PM UTC-7, Ed Lee wrote:

    "The most common form of laser rangefinder operates on the time of
    flight principle by sending a laser pulse in a narrow beam towards the
    object and measuring the time taken by the pulse to be reflected off
    the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder

    Yeah, for rangefinding the corner-cube reflector left on Luna, that
    simple scheme's workable. For shorter distances, though, modulation of
    an FM burst, and detection of the interference of outgoing and incoming
    to generate the difference frequency, is the most practical way of doing
    it.

    I'm pretty sure my Hot Wheels radar gun isn't "measuring the time" with
    a digital clock, directly.

    I believe most short distance laser rangefinders use a simple capacitive charging circuit with the outoing pulse as the start and the reflection as
    the terminator. The capacitor voltage measures the distance. An example is
    a CDN$35 unit from Amazon Canada:

    https://www.amazon.ca/Distance-Handheld-Portable-Precision- Apartment/dp/B08Y96T271/

    Other methods perform interferometric distance measurements. It is the most precise and fastest distance measurement method, but interferometric rangefinders are expensive and susceptible to damage. This makes them unreliable in the field.




    --
    MRM

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Anthony William Sloman@21:1/5 to Ed Lee on Fri Aug 12 22:23:17 2022
    On Saturday, August 13, 2022 at 12:39:13 PM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 7:37:13 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 12:01:58 PM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 6:57:16 PM UTC-7, whit3rd wrote:
    On Friday, August 12, 2022 at 6:19:41 PM UTC-7, Ed Lee wrote:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender.
    "

    https://en.wikipedia.org/wiki/Laser_rangefinder
    Yeah, for rangefinding the corner-cube reflector left on Luna, that simple scheme's workable. For shorter
    distances, though, modulation of an FM burst, and detection of the interference of outgoing
    and incoming to generate the difference frequency, is the most practical way of doing it.

    I'm pretty sure my Hot Wheels radar gun isn't "measuring the time" with a digital clock, directly.

    Yes, Bill and you are bring up all possible ways to measure distance. But OP specifically asked for digital processing of laser range-finder.
    But the OP is a a, and he's time-wasting half-wit. Nobody sane is going to spend time on responding to him. You are the sucker who did.
    It's a rare on-topic case related to electronics and worth answering.

    Not when a a asks the question.

    --
    Bill Sloman, Sydney

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ricky@21:1/5 to a a on Sat Aug 13 03:46:38 2022
    On Friday, August 12, 2022 at 2:49:04 PM UTC-4, a a wrote:
    On Friday, 12 August 2022 at 18:48:21 UTC+2, Ricky wrote:
    On Friday, August 12, 2022 at 12:06:42 PM UTC-4, TTman wrote:
    On 12/08/2022 14:46, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    GHz ASIC
    3E-9 second per meter


    FPGA...I worked on one...
    I have one of the laser devices. It measures to a fraction of an inch. That would be an equivalent frequency of maybe 100 GHz which is a bit difficult, even inside an FPGA. Does this require multiple inputs with varying delays to define timing to a
    finer resolution than the clock period?

    --

    Rick C.

    - Get 1,000 miles of free Supercharging
    - Tesla referral code - https://ts.la/richard11209
    thank you Ricky
    since iPhone claims Lidar in smartphone and parallel distance array calculation on-the-fly

    For 1cm resolution 10 GHz single point
    turns into 100 x 100 x 10 GHz clock frequency
    for 100 points x 100 points array

    What 100 x 100 point array???

    --

    Rick C.

    + Get 1,000 miles of free Supercharging
    + Tesla referral code - https://ts.la/richard11209

    --- SoupGate-Win32 v1.05
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  • From Ricky@21:1/5 to TTman on Sat Aug 13 04:42:24 2022
    On Saturday, August 13, 2022 at 7:24:12 AM UTC-4, TTman wrote:
    On 12/08/2022 17:48, Ricky wrote:
    On Friday, August 12, 2022 at 12:06:42 PM UTC-4, TTman wrote:
    On 12/08/2022 14:46, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    GHz ASIC
    3E-9 second per meter


    FPGA...I worked on one...

    I have one of the laser devices. It measures to a fraction of an inch. That would be an equivalent frequency of maybe 100 GHz which is a bit difficult, even inside an FPGA. Does this require multiple inputs with varying delays to define timing to a
    finer resolution than the clock period?

    How much did you pay for it?

    I don't recall exactly, but it was under $50 or I wouldn't have bought it.

    --

    Rick C.

    -- Get 1,000 miles of free Supercharging
    -- Tesla referral code - https://ts.la/richard11209

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From TTman@21:1/5 to Ed Lee on Sat Aug 13 12:27:29 2022
    On 12/08/2022 20:31, Ed Lee wrote:
    On Friday, August 12, 2022 at 9:06:42 AM UTC-7, TTman wrote:
    On 12/08/2022 14:46, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    GHz ASIC
    3E-9 second per meter


    FPGA...I worked on one...

    Too slow. I have only seen a few hundred MHz FPGA.
    Enough to get time of flight... My test gear used Atmel running at 20MHz
    to get +/- 50nS resolution, checking the FPGA output and my test gear simulating the return pulse and seeing the answer in the test kit,
    provided by the FPGA. Test pulse was designed to simulate 10Km out and back.

    --
    This email has been checked for viruses by Avast antivirus software. www.avast.com

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From TTman@21:1/5 to Ricky on Sat Aug 13 12:24:03 2022
    On 12/08/2022 17:48, Ricky wrote:
    On Friday, August 12, 2022 at 12:06:42 PM UTC-4, TTman wrote:
    On 12/08/2022 14:46, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?

    GHz ASIC
    3E-9 second per meter


    FPGA...I worked on one...

    I have one of the laser devices. It measures to a fraction of an inch. That would be an equivalent frequency of maybe 100 GHz which is a bit difficult, even inside an FPGA. Does this require multiple inputs with varying delays to define timing to a
    finer resolution than the clock period?

    How much did you pay for it?


    --
    This email has been checked for viruses by Avast antivirus software. www.avast.com

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cydrome Leader@21:1/5 to a a on Sat Aug 13 16:26:51 2022
    a a <manta103g@gmail.com> wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    Love all this retarded math and units.

    Here's the short story. Light travels about 1 foot per nanosecond. If you're measuring reflections the
    distance traveled is twice between you and the target, so this in essense doubles your resolution. A 1GHz
    clock should be fine for measuring in increments of fractions of a foot.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cydrome Leader@21:1/5 to Anthony William Sloman on Sat Aug 13 16:30:44 2022
    Anthony William Sloman <bill.sloman@ieee.org> wrote:
    On Saturday, August 13, 2022 at 11:19:41 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 6:12:58 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 11:00:46 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 5:52:21 PM UTC-7, bill....@ieee.org wrote: >> > > > On Saturday, August 13, 2022 at 9:10:07 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote: >> > > > > > > > > > On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote: >> > > > > > > > > > > On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    <snipped uninformed comment>
    Yes, we should.

    https://en.wikipedia.org/wiki/Tellurometer

    was the original wavelength-based range-finder, and it didn't send out a pulse and measure the time until it returned.

    Measuring the phase shift along the path to the reflector and back is a more practical scheme.

    This is talking about microwave. We are talking about lightwave (laser). >> > Both are electromagnetic waves and phase shift works for both. HP's laser interferomenter certainly measured to small fractions of the helium-neon laser wavelength (which I used to know to ten significant digits when we were designing one in).
    The difference is the much higher frequencies of lightwave vs. microwave.
    The bottom of the Tellurometer page offers a link to a page on laser rangefinders. I haven't clicked on it in years. Maybe you should.

    Yes, you should listen to your own advice:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder

    It isn't all that accurate. The other techniques can do better, but they do tend to be more expensive, as more accurate instruments can afford to be.

    "Multiple frequency phase-shift - this measures the phase shift of multiple frequencies on reflection then solves some simultaneous equations to give a final measure.

    Interferometry - the most accurate and most useful technique for measuring changes in distance rather than absolute distances."

    Is it 10 millionths of an in per "ring" on a optical flat with the blue/krypton light when measuring
    surface flatness? It's pretty amazing you can actually see such levels of interference. Autocollimators are
    pretty fascinating devices too.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cydrome Leader@21:1/5 to Ed Lee on Sat Aug 13 16:31:43 2022
    Ed Lee <edward.ming.lee@gmail.com> wrote:
    On Friday, August 12, 2022 at 7:30:48 PM UTC-7, whit3rd wrote:
    On Friday, August 12, 2022 at 7:01:58 PM UTC-7, Ed Lee wrote:
    On Friday, August 12, 2022 at 6:57:16 PM UTC-7, whit3rd wrote:
    On Friday, August 12, 2022 at 6:19:41 PM UTC-7, Ed Lee wrote:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder
    Yeah, for rangefinding the corner-cube reflector left on Luna, that simple scheme's workable. For shorter
    distances, though, modulation of an FM burst, and detection of the interference of outgoing
    and incoming to generate the difference frequency, is the most practical way of doing it.

    I'm pretty sure my Hot Wheels radar gun isn't "measuring the time" with a digital clock, directly.
    Yes, Bill and you are bring up all possible ways to measure distance. But OP specifically asked for digital processing of laser range-finder.
    Do you have an objection? A "laser range finder" is a broad class of instruments, with no particular
    'digital processing' specificity, and digital processing is not, in the general case, superior
    or practical in the pulse/clock-and-count scenario, so we discuss others.

    I am just responding to OP direct question of:
    "what chip, clocked at what frequency, is used to measure Time of Flight of laser light at sucjh short time intervals ?"

    LM555

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From John Larkin@21:1/5 to presence@MUNGEpanix.com on Sat Aug 13 09:38:06 2022
    On Sat, 13 Aug 2022 16:26:51 -0000 (UTC), Cydrome Leader <presence@MUNGEpanix.com> wrote:

    a a <manta103g@gmail.com> wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    Love all this retarded math and units.

    Here's the short story. Light travels about 1 foot per nanosecond. If you're measuring reflections the
    distance traveled is twice between you and the target, so this in essense doubles your resolution. A 1GHz
    clock should be fine for measuring in increments of fractions of a foot.


    Fast clocks are power hogs. There are better ways to measure
    nanoseconds.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From a a@21:1/5 to Cydrome Leader on Sat Aug 13 10:04:44 2022
    On Saturday, 13 August 2022 at 18:30:51 UTC+2, Cydrome Leader wrote:
    Anthony William Sloman <bill....@ieee.org> wrote:
    On Saturday, August 13, 2022 at 11:19:41 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 6:12:58 PM UTC-7, bill....@ieee.org wrote: >> > On Saturday, August 13, 2022 at 11:00:46 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 5:52:21 PM UTC-7, bill....@ieee.org wrote:
    On Saturday, August 13, 2022 at 9:10:07 AM UTC+10, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote: >> > > > > > > > > On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    <snipped uninformed comment>
    Yes, we should.

    https://en.wikipedia.org/wiki/Tellurometer

    was the original wavelength-based range-finder, and it didn't send out a pulse and measure the time until it returned.

    Measuring the phase shift along the path to the reflector and back is a more practical scheme.

    This is talking about microwave. We are talking about lightwave (laser).
    Both are electromagnetic waves and phase shift works for both. HP's laser interferomenter certainly measured to small fractions of the helium-neon laser wavelength (which I used to know to ten significant digits when we were designing one in).
    The difference is the much higher frequencies of lightwave vs. microwave. >> > The bottom of the Tellurometer page offers a link to a page on laser rangefinders. I haven't clicked on it in years. Maybe you should.

    Yes, you should listen to your own advice:

    "The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender."

    https://en.wikipedia.org/wiki/Laser_rangefinder

    It isn't all that accurate. The other techniques can do better, but they do tend to be more expensive, as more accurate instruments can afford to be.

    "Multiple frequency phase-shift - this measures the phase shift of multiple frequencies on reflection then solves some simultaneous equations to give a final measure.

    Interferometry - the most accurate and most useful technique for measuring changes in distance rather than absolute distances."
    Is it 10 millionths of an in per "ring" on a optical flat with the blue/krypton light when measuring
    surface flatness? It's pretty amazing you can actually see such levels of interference. Autocollimators are
    pretty fascinating devices too.

    Very cheap unique wavelength light for using with Optical Flats... Using a 532nm. 50mw LED laser
    22,458 views
    27 Jan 2018
    546
    Dislike
    Share
    Clip
    Save
    Pierre's Garage
    18.3K subscribers
    In this video, I’ll be showing as a proof of concept how to make a real cheap, but, quite reliable light source using a 50 mw. LED pointer with a fixed wavelength in order to use with Optical Flats.
    A Xenon or any laboratory type fixed wavelength is quite out of reach for any hobbyist or small shop owner, this option of using a LED with a known wavelength isn’t pretending to be as precise as a multi thousand of dollars instrument, but, will allow
    for reasonably accurate measurements in non-critical situations.
    The fixed wavelength allows the Optical Flats to create a pattern by reflection and diffraction on a polished surface, the goal is to measure the flatness of that surface, and, knowing the wavelength we’re being able to quantify the amount of
    irregularity if there is any.

    Please take note that I'm using the term laser for the light emitting diodes, in fact a real laser is a very different technology, it's a bad habit to call a LED a laser diode...

    https://youtu.be/xSYl7q6yKPU

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Phil Hobbs@21:1/5 to Ed Lee on Sat Aug 13 13:42:30 2022
    Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    3GHz (reasonable clock) for 10cm resolution.

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    https://en.wikipedia.org/wiki/Oversampling
    for higher resolution.


    The usual method is a time-to-amplitude converter.

    Cheers

    Phil Hobbs

    --
    Dr Philip C D Hobbs
    Principal Consultant
    ElectroOptical Innovations LLC / Hobbs ElectroOptics
    Optics, Electro-optics, Photonics, Analog Electronics
    Briarcliff Manor NY 10510

    http://electrooptical.net
    http://hobbs-eo.com

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ricky@21:1/5 to Cydrome Leader on Sat Aug 13 10:40:05 2022
    On Saturday, August 13, 2022 at 12:26:58 PM UTC-4, Cydrome Leader wrote:
    a a <mant...@gmail.com> wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference
    Love all this retarded math and units.

    Here's the short story. Light travels about 1 foot per nanosecond. If you're measuring reflections the
    distance traveled is twice between you and the target, so this in essense doubles your resolution. A 1GHz
    clock should be fine for measuring in increments of fractions of a foot.

    How about fractions of an inch, like a tenth?

    --

    Rick C.

    -+ Get 1,000 miles of free Supercharging
    -+ Tesla referral code - https://ts.la/richard11209

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cydrome Leader@21:1/5 to Ricky on Sat Aug 13 19:31:16 2022
    Ricky <gnuarm.deletethisbit@gmail.com> wrote:
    On Saturday, August 13, 2022 at 12:26:58 PM UTC-4, Cydrome Leader wrote:
    a a <mant...@gmail.com> wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote:
    what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference
    Love all this retarded math and units.

    Here's the short story. Light travels about 1 foot per nanosecond. If you're measuring reflections the
    distance traveled is twice between you and the target, so this in essense doubles your resolution. A 1GHz
    clock should be fine for measuring in increments of fractions of a foot.

    How about fractions of an inch, like a tenth?

    You better ask the trillion of centimeters per second folks to do the math for you in that.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From jlarkin@highlandsniptechnology.com@21:1/5 to pcdhSpamMeSenseless@electrooptical. on Sun Aug 14 09:24:51 2022
    On Sat, 13 Aug 2022 13:42:30 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:

    Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote: >>>>>>>>>>> On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote: >>>>>>>>>>>> what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once.
    so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    3GHz (reasonable clock) for 10cm resolution.

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    https://en.wikipedia.org/wiki/Oversampling
    for higher resolution.


    The usual method is a time-to-amplitude converter.

    Cheers

    Phil Hobbs

    One way is to use a simple analog time stretcher and a
    modest-frequency counter.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From a a@21:1/5 to jla...@highlandsniptechnology.com on Sun Aug 14 13:55:56 2022
    On Sunday, 14 August 2022 at 18:24:59 UTC+2, jla...@highlandsniptechnology.com wrote:
    On Sat, 13 Aug 2022 13:42:30 -0400, Phil Hobbs <pcdhSpamM...@electrooptical.net> wrote:

    Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote: >>>>>>>>> On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote: >>>>>>>>>> On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote: >>>>>>>>>>> On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote: >>>>>>>>>>>> what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once. >>>>>>> so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    3GHz (reasonable clock) for 10cm resolution.

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    https://en.wikipedia.org/wiki/Oversampling
    for higher resolution.


    The usual method is a time-to-amplitude converter.

    Cheers

    Phil Hobbs
    One way is to use a simple analog time stretcher and a
    modest-frequency counter.
    just watched video

    kinect - sensor IR projection

    https://youtu.be/MlTf0yYQjSg?t=43

    let me know if the projected IR points cloud is made of static preset points and what is a role of the pattern ?

    Can theory behing Kinect be turned into large scale indoor 3D scanner, replacing lenses in ca,meras,
    moving IR projector far from VGA camera to read depth at large distance ?

    Can IR pattern projected be replaced by another, higher IR power/ higher resolution pattern ?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Lee@21:1/5 to a a on Mon Aug 15 05:51:28 2022
    On Sunday, August 14, 2022 at 1:56:01 PM UTC-7, a a wrote:
    On Sunday, 14 August 2022 at 18:24:59 UTC+2, jla...@highlandsniptechnology.com wrote:
    On Sat, 13 Aug 2022 13:42:30 -0400, Phil Hobbs <pcdhSpamM...@electrooptical.net> wrote:

    Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote: >>>>>>>> On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote: >>>>>>>>> On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote: >>>>>>>>>> On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote: >>>>>>>>>>> On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote: >>>>>>>>>>>> what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once. >>>>>>> so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone,
    is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point >>
    3GHz (reasonable clock) for 10cm resolution.

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    https://en.wikipedia.org/wiki/Oversampling
    for higher resolution.


    The usual method is a time-to-amplitude converter.

    Cheers

    Phil Hobbs
    One way is to use a simple analog time stretcher and a
    modest-frequency counter.
    just watched video

    kinect - sensor IR projection

    https://youtu.be/MlTf0yYQjSg?t=43

    let me know if the projected IR points cloud is made of static preset points and what is a role of the pattern ?

    Can theory behing Kinect be turned into large scale indoor 3D scanner, replacing lenses in ca,meras,
    moving IR projector far from VGA camera to read depth at large distance ?

    Can IR pattern projected be replaced by another, higher IR power/ higher resolution pattern ?

    Nobody's talking, so i will.

    This IR stuff has nothing to do with measuring distance, unless you have to do it in the dark. If you are asking about 3D distance mapping, you have to enable it one at a time, even if you have a 100x100 laser matrix.

    As someone pointed out, you can buy existing chips. But if you are integrating it into laser matrix, you might have to build your own hardware counters and routing circuits. 5GHz counters can handle at least an inch or couple cm resolution, before
    oversampling. You can turn off most of the circuit except for fraction of a second, in order to save power.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From a a@21:1/5 to Ed Lee on Mon Aug 15 07:29:49 2022
    On Monday, 15 August 2022 at 14:51:32 UTC+2, Ed Lee wrote:
    On Sunday, August 14, 2022 at 1:56:01 PM UTC-7, a a wrote:
    On Sunday, 14 August 2022 at 18:24:59 UTC+2, jla...@highlandsniptechnology.com wrote:
    On Sat, 13 Aug 2022 13:42:30 -0400, Phil Hobbs <pcdhSpamM...@electrooptical.net> wrote:

    Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote: >>>>>>> On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote: >>>>>>>> On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote: >>>>>>>>> On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote: >>>>>>>>>> On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote: >>>>>>>>>>> On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote: >>>>>>>>>>>> what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once. >>>>>>> so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone, >>>>>>> is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    3GHz (reasonable clock) for 10cm resolution.

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    https://en.wikipedia.org/wiki/Oversampling
    for higher resolution.


    The usual method is a time-to-amplitude converter.

    Cheers

    Phil Hobbs
    One way is to use a simple analog time stretcher and a
    modest-frequency counter.
    just watched video

    kinect - sensor IR projection

    https://youtu.be/MlTf0yYQjSg?t=43

    let me know if the projected IR points cloud is made of static preset points
    and what is a role of the pattern ?

    Can theory behing Kinect be turned into large scale indoor 3D scanner, replacing lenses in ca,meras,
    moving IR projector far from VGA camera to read depth at large distance ?

    Can IR pattern projected be replaced by another, higher IR power/ higher resolution pattern ?
    Nobody's talking, so i will.

    This IR stuff has nothing to do with measuring distance, unless you have to do it in the dark. If you are asking about 3D distance mapping, you have to enable it one at a time, even if you have a 100x100 laser matrix.

    As someone pointed out, you can buy existing chips. But if you are integrating it into laser matrix, you might have to build your own hardware counters and routing circuits. 5GHz counters can handle at least an inch or couple cm resolution, before
    oversampling. You can turn off most of the circuit except for fraction of a second, in order to save power.
    thank you
    I need to learn more about laser IR projector in Kinect

    "The Kinect infrared sensor sees the sofa as a large number of tiny dots. The Kinect sensor constantly projects these dots over the area in its view. If you want to view the dots yourself, it’s actually very easy; all you need is a video camera or
    camcorder that has a night vision mode. A camera in night vision mode is sensitive to the infrared light spectrum that the Kinect distance sensor uses.

    Figure 1-6, for example, was taken in complete darkness, with the sofa lit only by the Kinect. The infrared sensor in the Kinect is fitted with a filter that keeps out ordinary light, which is how it can see just the infrared dots, even in a brightly lit
    room. The dots are arranged in a pseudo-random pattern that is hardwired into the sensor. You can see some of the pattern in Figure 1-7.


    https://www.microsoftpressstore.com/articles/article.aspx?p=2201646

    I need to know how pseudo-random pattern of dots is generated by IR laser projector
    Resolution is not low

    https://www.microsoftpressstore.com/content/images/chap1_9780735663961/elementLinks/httpatomoreillycomsourcemspimages1239382.jpg

    dots are not lined up so it seems to me some laser optics / lens is involved

    - single laser diode + lens with drilled pattern ?

    "pseudo-random pattern that is hardwired into the sensor.

    not sure what they mean, since to have pseudo-random[pattern hardwired into the sensor
    you need to get (x,y) coordinates for every single point

    I recall another algorithm to generate 3D depth images by moving camera, based on blur effect,
    since closer objects move faster in the plane perpendicular to the camera axis so if we stack a number of images/frames together, we get blur effect for the closer objects to intensify.

    ----
    Kinect`s infrared projector in action
    51,995 views
    17 Nov 2010
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    Vladimir Seregin
    374 subscribers
    Video recorded with an regular webcam without IR filter on it. https://www.youtube.com/watch?v=brnIty7mh2Q

    since every single dot is clearly visible in regular HD webcam
    so a number of dots projected must be below HD resolution

    --
    there is a number of web links but they refer to IR camera resolution only

    640 x 480
    The Kinect sensor returns 16 bits perpixel infrared data with a resolution of 640 x 480as an color image format, and it supports up to30 FPS. Following are the couple of images ( taken in a complete dark room) that captures from IR stream data.
    Get the IR Stream and control the IR Emitter – Kinect for Windows SDK ... abhijitjana.net/2013/01/11/get-the-ir-stream-and-control-the-ir-emitter-kinect-for-windows-sdk/
    abhijitjana.net/2013/01/11/get-the-ir-stream-and-control-the-ir-emitter-kinect-for …


    Get the IR Stream and control the IR Emitter – Kinect for Windows SDK

    https://abhijitjana.net/2013/01/11/get-the-ir-stream-and-control-the-ir-emitter-kinect-for-windows-sdk/#:~:text=The%20Kinect%20sensor%20returns%2016%20bits%20perpixel%20infrared,dark%20room%29%20that%20captures%20from%20IR%20stream%20data.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From a a@21:1/5 to Ed Lee on Mon Aug 15 07:35:09 2022
    On Monday, 15 August 2022 at 14:51:32 UTC+2, Ed Lee wrote:
    On Sunday, August 14, 2022 at 1:56:01 PM UTC-7, a a wrote:
    On Sunday, 14 August 2022 at 18:24:59 UTC+2, jla...@highlandsniptechnology.com wrote:
    On Sat, 13 Aug 2022 13:42:30 -0400, Phil Hobbs <pcdhSpamM...@electrooptical.net> wrote:

    Ed Lee wrote:
    On Friday, August 12, 2022 at 3:40:38 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 23:58:11 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 2:31:31 PM UTC-7, a a wrote:
    On Friday, 12 August 2022 at 22:37:28 UTC+2, Ed Lee wrote:
    On Friday, August 12, 2022 at 1:06:35 PM UTC-7, a a wrote: >>>>>>> On Friday, 12 August 2022 at 21:55:26 UTC+2, Ed Lee wrote: >>>>>>>> On Friday, August 12, 2022 at 11:45:18 AM UTC-7, a a wrote: >>>>>>>>> On Friday, 12 August 2022 at 15:46:11 UTC+2, Ed Lee wrote: >>>>>>>>>> On Friday, August 12, 2022 at 3:23:57 AM UTC-7, a a wrote: >>>>>>>>>>> On Friday, 12 August 2022 at 12:18:44 UTC+2, a a wrote: >>>>>>>>>>>> what chip, clocked at what frequency, is used to measure Time of Flight of laser light at such short time intervals ?
    GHz ASIC
    3E-9 second per meter
    c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    3E-9 s/m x 300 000 000 m/s = 0.9

    ok
    but for 1 cm resolution
    we need 100 x faster clock

    and for parallel analysis of point cloud 100 x 100
    we need 100 x 100 faster clock

    could you explain ?
    There is no point in measuring all 10,000 points all at once. >>>>>>> so do you suggest,
    what is marketed by iPhone and called Lidar in smartphone, >>>>>>> is a single point Laser Range Meter functionality ?

    If you are correct, so why do they present 2D laser scanner functionality on images ?

    Single point laser Lidar requires rotating head to work

    \so some kind od mechanics is involved
    Yes, precisely, to have better relative positioning with multi-sensors. However, there is no need to measure them all within E-9 second.
    -E-9 second cloc k is for 1m resolution
    for 1 cm resolution
    you need
    E-9 * 10-2 second clock

    but we still discuss a single-point operation
    With 5GHz (close to current fab cap) hardware counters, we can count pulses to the same point 100 times. If we get 25 pulses of 1 meter and 75 pulses of 1.1 meter, we can guess that the distance is close to 1.025 meters.

    Give me $100,000 and i can build you the chip to prove it.
    -==c = 299 792 458 m/s > >>> c = 300 000 000 m/s

    -===3E-9 s/m x 300 000 000 m/s = 0.9

    300 000 000 m/s = 100 * 300 000 000 cm/s

    = 30 000 000 000 cm/s

    so you need 30 GHz clock x 2 to get 1 cm resolution for a single point

    3GHz (reasonable clock) for 10cm resolution.

    ok, for 1 m distant object
    300 MHz x 2 clock can do the job

    but if you need mobile laser range meter to scan objects on the fly, to act as 2D scanner,
    1 cm counts and makes the difference

    https://en.wikipedia.org/wiki/Oversampling
    for higher resolution.


    The usual method is a time-to-amplitude converter.

    Cheers

    Phil Hobbs
    One way is to use a simple analog time stretcher and a
    modest-frequency counter.
    just watched video

    kinect - sensor IR projection

    https://youtu.be/MlTf0yYQjSg?t=43

    let me know if the projected IR points cloud is made of static preset points
    and what is a role of the pattern ?

    Can theory behing Kinect be turned into large scale indoor 3D scanner, replacing lenses in ca,meras,
    moving IR projector far from VGA camera to read depth at large distance ?

    Can IR pattern projected be replaced by another, higher IR power/ higher resolution pattern ?
    Nobody's talking, so i will.

    This IR stuff has nothing to do with measuring distance, unless you have to do it in the dark. If you are asking about 3D distance mapping, you have to enable it one at a time, even if you have a 100x100 laser matrix.

    As someone pointed out, you can buy existing chips. But if you are integrating it into laser matrix, you might have to build your own hardware counters and routing circuits. 5GHz counters can handle at least an inch or couple cm resolution, before
    oversampling. You can turn off most of the circuit except for fraction of a second, in order to save power.

    from https://www.dfki.de/fileadmin/user_upload/import/8767_wasenmuller2016comparison.pdf

    The Kinect v1 measures the depth with the Pattern Projection principle, where
    a known infrared pattern is projected into the scene and out of its distortion the depth is computed. The Kinect v2 contains a Time-of-Flight (ToF) camera
    and determines the depth by measuring the time emitted light takes from the camera to the object and back. Therefore, it constantly emits infrared light with
    modulated waves and detects the shifted phase of the returning light [17, 18]. In
    the following, we refer to both cameras (Pattern Projection and ToF) as depth camera

    not sure how ToF can be live implemented into 2D image analysis

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)