Grazing incidence gratings for dye lasers

Laser Components now offer a range of grazing incidence gratings manufactured by Optometrics, suitable for use in dye laser systems. Grazing incidence is a simple and inexpensive optical configuration that can tune and increase the resolution of a dye laser.

A holographic grating, functioning as an end reflector in a dye laser cavity, is positioned so that laser radiation strikes the grating almost perpendicular to the grating normal. As the angle of incidence approaches 89°, a relatively large area of the grating is illuminated by the laser beam, increasing angular dispersion and resolving power significantly. The sizes of the grazing and mirror (12.7 x 50.8mm) are optimised for grazing incidence. The grating is fixed and tuning is achieved by rotation of the mirror. The laser beam is diffracted twice in grating incidence, resulting in a two fold increase in resolution. Low grating efficiency is characteristic of the grazing incidence configuration but is compensated for by the high gain of the dyes used.