BL> My story is that it must have been a reflection or something.
 BL> Who knows? A reversing light is not illegal.

 JT> Bit bright for a reversing light eh bob?

  Not really. A flash is bright in a room, but not at a range of 30m,
and by the time the flash registers, it's already gone.

 BL> I'll have two minutes even if the cop is mobile... and by then
 BL> I've turned the flash function off.

 JT> You have to careful about this method, being able to turn the
 JT> thing off if in a position to be found out, like if they almost
 JT> got you on the same stretch of road three times in a row, and
 JT> this time you forgot to turn the thing on. 

  Make it automatic... it only turns off after a flash.

 BL> If you were involved in an accident, you could simply strip off
 BL> the tape.

 JT> Yeah, but the cost for being caught out is rather large. Sure
 JT> the risk is lower, but the cost is also higher. Are you
 JT> prepared to pay the price? 

  Cost? You'd simply act amazed and say "some bastard at work must
have done it!" In fact, I've been tempted. There's a hoon across the
street who is a real candidate. "R" makes a great "P"
with a touch of
yellow tape.

 BL> Lasers don't use doppler...

 JT> Oh, ok, then explain to me how they DO work. Well stuff me if
 JT> that technique isn't based on the doppler effect.

  They measure the range differential over time. Doppler is very
common in toy police speed radar, but it is not the way the big boys
do it when they want to measure velocity and distance, for instance
when tanks are shooting at each other. The advantage of a laser
ranging device is that it can measure vectors. Doppler can't.

 BL> Bullshit. I don't know what you call a tight-beam laser, but
 BL> the ones they use for ranging measurements focus to about 2mm
 BL> diameter. To damage tissue in the eye you need 10 kw/sq.m, and
 BL> that's 125mW.

 JT> My question is, is *that* bright enough to cause even a
 JT> possible problem?

  I just told you. No. You need 10kw/sq.m to damage a retina, and the
laser is pulsed anyway.

Regards,
Bob
___ Blue Wave/QWK v2.12
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