Due to the extensive use of lasers in aiming devices, range fmders, and in remote sensing, the protection of eyes and sensors from
laser beams becomes critically important. It has been a challenging task to provide protection from wave-length tunable lasers without
the serious sacrifice of vision capability. In this work, we describe two different approaches which can significantly attenuate the
laser beam through the whole visible region. One approach is to use specific geometric configuration with thin film aluminum
mirrors"2. The other is to use the properties of reverse saturable absorption of fullerene3'4. The combination of these two approaches
can possibly become an effective device for eye protection from high power tunable lasers. The principle and mechanism to achieve
eye protection will also be discussed.
The goal for eye and sensor protection is to attenuate the amount of incident light below the damage threshold. The ANSI standards
indicate that for visible wavelengths and nanosecond pulse durations, the maximum permissible exposure on the surface of the comeas
is about 0.2 J. The damage threshold by a nanosecond laser on a rhesus monkey was measured to be of the order of a few
microjoules5.
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