Glossary of Laser Terms-I

Infrared Radiation (IR)

Invisible electromagnetic radiation with wavelengths which lie within the range of 0.70 to 1000 µm. These wavelengths are often broken up into regions: IR-A (0.7-1.4 µm), IR-B (1.4-3.0 µm) and IR-C (3.0-1000 µm).

Iris  

The annular pigmented structure that lies behind the cornea of the human eye. The iris forms the pupil.

 Intrabeam Viewing  

The viewing condition whereby the eye is exposed to all or part of a direct laser beam or a specular reflection.

Irradiance (E)    

Radiant flux (radiant power) per unit area incident upon a given surface. Units: Watts per square centimeter. (Sometimes referred to as power density, although not exactly correct).