AN INTERFEROMETRIC MEASUREMENT OF INDEX OF REFRACTION,
Abstract
Of the several common methods for measurement of the index of refraction of solid optical materials, only one, the minimum deviation method, can conveniently be used for materials whose refractive index exceeds 1.8. The minimum deviation method requires that a large prism of the optical material be constructed; this is not always possible or feasible for some crystalline optical materials that are of current interest. A method for measurement of index of refraction is presented which requires a thin flat plate of the optical material and is unlimited in the range of refractive index it can cover. The method uses a two-beam interferometer to determine the optical path length through the flat plate by tipping away from normal incidence through a measured angle. It may be used in the visible portion of the spectrum directly, or extended to other spectral regions with the use of a suitable detector. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 13, 1964
- Accession Number
- AD0437768
Entities
People
- Michael S. Shumate
Organizations
- California Institute of Technology