Internal reflection prisms were used to produce a narrow angular range of high reflectivity within a laser cavity. The selectivity was obtained from the sharp angular variation of internal reflectivity near the critical angle. Angular mode selection of a Nd:glass normal laser was achieved by this critical internal reflection (CIR) technique. Two-dimensional angular mode selection was observed with two orthogonal Lummer–Gehrcke plates within the laser cavity.
© 1967 Optical Society of America
Original Manuscript: July 25, 1966
Published: March 1, 1967
L. G. DeShazer and E. A. Maunders, "Laser Mode Selection by Internal Reflection Prisms," Appl. Opt. 6, 431-435 (1967)