ajdelange
Well-known member
- First Name
- A. J.
- Joined
- Dec 8, 2019
- Threads
- 4
- Messages
- 3,213
- Reaction score
- 3,403
- Location
- Virginia/Quebec
- Vehicles
- Tesla X LR+, Lexus SUV, Toyota SR5, Toyota Landcruiser
- Occupation
- EE (Retired)
They don't call it LIDAR because it isn't LIDAR because there is no scanning AFAIK. LIDAR does not imply data collection any more than RADAR or SONAR does. They all collect data. Now of course I don't have any design data on ToF and I conclude that there is no scanning because the description that is available to me does not suggest any. It seems that there is a flash lamp that illuminates the whole scene at once and that TOF is measured in each pixel which detects a signal with TOA of each "pulse" noted (at each pixel - there may be more than one target return). That TOA is data used I don't know how but it evidently can be combined with the visible band data to produce interesting pictures. In this sense the system is a RADAR (that happens to operate in the NIR and visible spectrum) with the lens is a very high gain (narrow beamwidth) RECEIVE antenna which gives high resolution in x and y. The TOA data adds the z dimension and reccording over time, t.Samsung probably markets their technology as "ToF" rather than "LiDAR" because the latter implies a device that gathers data, while the purpose of the former is to create photographs.
Now a LIIDAR works in the opposite fashion, X and Y information comes from very high effective antenna gain during TRANSMIT as the coherent laser beam is highly collimated. The receive antenna does not need to have nearly the resolution of a large aperture lens because the resolution of the transmitter antenna is sufficient. In layman's terms x and y data are derived from where the beam is pointed at the time the laser is fired.
Now the latest iPhone does have a true scanning LIDAR in it. The blows my mind as much as the ToF technology but there it is! What I wonder, of course, is how they implement the scanning.. Piezo electric something or other would be my guess.The newest iPhones have LiDAR in the camera, and they provide an API for applications to leverage the raw data.
Anyway, LIDAR implies only that it is an optical RADAR - not what is done with its data. SONAR indicates that it is an accoustic RADAR - not what is done with it's data. Etc.
Sponsored