PPRuNe Forums - View Single Post - Virgin Atlantic flight from London to NY returns after pilot hurt in laser incident
Old 16th Feb 2016, 17:40
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Airbubba
 
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I'm going to risk weighing in from the perspective of a background in physics (as well as avionics).
An 808nm (green) 50mW l@ser shone at close range into the eye for more than a few milliseconds will could inflict permanent injury.
808 nm is green?

All this time I thought it was infrared...

Are you maybe thinking of the very common green 532 nm DPSS laser with an 808 nm GaAlAs pumping diode?

Exposure is considerably reduced by distance. For incoherent light (such as a bulb) the power of the light reduces by the inverse square of the radius, which is not true for a perfectly coherent l@ser source. An ideal l@ser will have the same power at any distance because the energy does not diverge.
Aren't you confusing coherence with collimation? It's the collimation that keeps the power from dropping much with distance, not the coherence, right? In fact, don't laser diodes (with a short coherence distance) often use a collimating lens?

Last edited by Airbubba; 16th Feb 2016 at 17:59.
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