User talk:Tlaux

We need to ensure we are not adding inaccurate or inconsistent content to 3D Flash LIDAR. A case in point is introducing a "homo-dyne" approach.

The following section (in "") kept re-appearing with no factual basis:

"A simpler "time-of-flight" 3D camera was invented in the early 90's that does not require triggers and counters. This 3D camera measures the time-of-flight of the illuminating pulse indirectly by synchronous gating of the received pulse and detecting the received photons in an ordinary image sensor. A homo-dyne detection is accomplished this way with the number of photons being proportional to distance.[5][unreliable source] Most practical time-of-flight cameras[disputed – discuss] measure the photons of the received pulse after a single synchronous gating with an electronic shutter.[6][verification needed][7][not in citation given (See discussion.)]"

The "Gated" approach described using "homo-dyne" detection (frequency modulation) requires mixing of primary and secondary laser pulses to derive a measurement. This approach is a complex methodology that has inherent range limitations based upon harmonic overlap occurring at specific ranges from the emitter/receiver caused when the harmonic (frequency) duplicates itself. This renders the sensor unable to determine actual range measurements when there is overlap.

By comparison, the 3D Flash LIDAR methodology uses a single "pulse" of laser energy that penetrates the field of view, then reflects the same pulsed energy back to the focal plane array's individual pixels from the objects in the field of view. This uses a direct measurement/timing approach. The individual pixels measure the single pulse's time-of-flight from and back to the camera rather than using a complex (and range limited) frequency modulated approach. Coincidentally with the same range pulse capture, intensity is captured as well.