Re: laser poinerrs and wavelength dependance

["Tom Johnson" <tjohnson@radtrain.com>]

>Common laser pointers in the USA run at 5 mW at 670 nm. The same spot or a
>brighter spot can be projected using below 1 mW at 635 nm because the eye
>responds much more to 635 nm energy than 670 nm energy. Risk of acute laser
>injury is not wavelength dependent so buying 635 nm laser pointers allows
>for an improvement in safety.

You may want to look more closely at ANSI Z136.1-1993; ALL laser injury is
wavelength dependant. In fact, one cannot perform a laser safety calculation
without knowing the wavelength. Additionally, the response of the eye to 532
nm light (doubled YAG) is significantly greater than either 635 nm diode or
670 nm laser, so that when a lower energy level should is used with the 532
nm, it appears to be just as bright or brighter to the eye.

Tom Johnson
tjohnson@radtrain.com

Recommended new warning label: "Do not look into laser with remaining good
eye"

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