Laser eye safety is a measure of how vulnerable the eye is to damage from a particular Laser source. This vulnerability is primarily affected by the output power and the Wavelength (color) of the laser light. Communication lasers are typi cally available in only a few wavelengths: 780nm, 850nm, 980nm, 1310nm and 1550nm. The eye is much more sensitive to short wavelengths such as 780nm than 1550nm. Wavelengths above 850nm are invisible to the eye, but still ca pable to causing damage. Class I laser devices are the safest. Class III laser devices are the least safe. Eye safety requirements in the US are specified by CDRH (21 CFR 1040.10 & 1040.11).