Hi,
I'm an engineer in the UK seeking methods of detecting so called safety cameras when they are pointed at me. I noticed a few items a while back which discussed the matter, but no conclusions were reached.
My research has found a report from Laser Technology Inc. (LTi), where they have listed the detailed spec of their 20-20 in order to comply with the eye safety requirements of the US authorities. I have a .PDF of the report, but the parameters are:-
Marksman 20/20:-
Laser diode wavelength 904nm
PRF 125Hz
Pulse Duration 12 ns
Pulse Energy 416nJ
Peak Pulse Power 34.7W
Average Power 52mW
Speed Measurement Distance: 30 ft to 3500 ft
Acquisition Time: 0.3 seconds
I have similar data for the stalker lidar:-
wavelength 905nm +- 10nm
Divergence <3 mrad
PRF 130Hz
I have also found a few PhD theses, and a useful suite of circuits at http://www.imagineeringezine.com/files/air-bk2.html
It would seem viable to construct a receiver capable of detecting 904nm laser radiation. The issue is would such a receiver give enough warning?
If anyone from the previous threads has devised any circuits or has any advice, I would like to share what I have with them.
Simon Bond MEng, BSc(Hons),IEng,MRAeS
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