There's various sources for LIDAR,
not being able to post links (I got told of for that last time)
as below
"The "Distance Between Cars" feature, or DBC, is an optional feature that can be integrated into the firmware capabilities of LTI's Marksman and Ultralyte laser guns. This special operating mode is used to help enforce laws against tailgating by measuring the time and distance between two moving vehicles.
Although DBC technology has been available since 1995, up until recently it has been mostly restricted to foreign markets. However, recently this feature has gained interest in the US, and it is reportedly being used or tested in a number of US jurisdictions, including some areas of Oregon, Colorado, Arizona, New Mexico, and Tennessee.
One NHTSA research report describes the basic process required for taking a DBC measurement: "
Decatur wrote:1- Radar can target an individual vehicle.
2-Radar will not register the speed of "any" object in its field. It most certainly won't pick up a tree swaying.
3-Lidar does not record an image of the licence plate unless that manufacture makes a camera attachment for that particular lidar (not used in Ontario to my knowledge) and it certainly doesn't measure the distance between vehicles. (It will measure the distance to a single vehicle though.
Apparently if it's on wiki it must be true!