HumanPerceptionOfInfraredLasers

A paper in the early '80s on research conducted in Russia, indicates reports about lasers may include colors that are not there. The dark-adapted eye sees a doubled-frequency response for NIR Lasers. It appears possible to detect COIL laser light or glint with the eye. Whether the eye is damaged is another question.

"Perception of Infrared Radiation of Lasers by the Human Eye," by V. Ye. Prokop'yev, Institute of Atmospheric Optics, Siberian Division, U.S.S.R. Academy of Sciences, Tomsk; Biofizika 25: No.2, pp. 315 - 317, Mar/Apr 1980.
Journal of Atmospheric and Oceanic Optics on-line index goes back to only 1988. (Download 198 KB pdf)

Here is a short abstract summary:

The article states that 0.95 micron radiation is perceived as red, but that 1 to 1.3 micron lasers are perceived at half the wavelength. They used external measurements and a monochromator to make sure that the light was not being doubled in frequency before entering the eye and to make color assessments accurate. Tests were conducted in a darkened room. I believe this means a dark-adapted eye, having a pupil size about 8mm diameter. The pulses used were 10 to 20 nsec. Powers used were usually bounded by .001 Joule, but up to 10,000 W/cm2 was used and repetition frequencies as high as 10,000 Hz. They estimated the wavelength accuracy to be 0.003 microns.

Results were as follows:

Incident wavelength (um)Perceived wavelength (um)Threshold Power (W/cm2)Doping
1.00200.50103-10Eu+
1.03220.51613-10Yb
1.13030.56515-10Ba
1.27140.635730-50Yb
1.5000--Ba


Additional Reading

"Frequency up-conversion of infrared laser radiation in the human retina," Laser Physics 16:7, July 2006, pgs 1078-1081. The Bibliography and Abstract indicate power up to 150 W/cm2 was used on human eyes.

Created by brian. Last Modification: Friday 01 of June, 2007 13:32:43 EDT by admin.