Refractive variation of a material, also referred to as homogeneity, is one of the important properties of optical components. Material inhomogeneity causes refractive index variation, which can manifest itself as sharp, banded areas or as a gradient of the refractive index across a larger area of the sample. Material index variations must be classified to ensure that their effect is within the tolerance of a given optical design.
ZYGO laser interferometers offer a wide range of options for qualifying the homogeneity of optical materials, as well as built-in analysis within the comprehensive Mx data acquisition and analysis software.
Verifire MST - interferometer suitable for material homogeneity qualification of parallel glass surfaces. Provides simultaneous measurement of the transmitted wavefront of the glass and removal of surface deformation effects (required to obtain accurate material measurements). The property of simultaneous MST measurement reduces measurement inaccuracy while preserving important linear homogeneity components that are normally lost using other metrology methods.
Verifire and Dynafiz interferometers provide similar wedge optics measurement capabilities with a data acquisition and analysis software package designed specifically for materials homogeneity measurements.
