Quantitative refractive index inhomogeneity measurement - by measuring deflections of beams passing through different regions of component blanks, for UV visible or IR regions

摘要

A method of quantitative measurement of inhomogeneities in refractive indices of optically transparent, plane parallel bodies in the ultraviolet, visible, and infra-red spectral regions is esp. applicable to blanks for manufacture of expensive optical components. It gives precise measurement results, esp. in the infra-red region, with relative economy. A narrow parallel beam is passed through several regions of a plane parallel body. The deflections associated with the individual regions are measured from the intensities at the line image edges. The linear image edges are held linear by suitable arrangement of the aberrations of the optical elements affecting the beam and of the plane of adjustment. The deflection data is evaluated using data processors and represented in quasi-three-dimensional form.