A technique is proposed to measure cylindrically symmetric refractive index profiles of transparent rods. A probe ray is incident to the side of the rod, and its emergent point is observed on an end surface of the rod. A simple relationship between incident and emergent ray positions is used to determine the index profile. The profile of a graded index rod lens was measured with an accuracy to within 1 part in 103. An extension of the method to a more general profile distribution is discussed.
© 1983 Optical Society of America
Dennis Gregoris and Keigo lizuka, "Ray tracing method for refractive index profiling," Appl. Opt. 22, 1820-1823 (1983)