| CPC G01M 11/0264 (2013.01) [G02B 27/62 (2013.01)] | 17 Claims |
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1. A method for testing imaging performance of an optical system, the method comprising:
positioning a test target at an object plane of the optical system;
operating the optical system to illuminate the test target and generate an image beam;
operating a focusing stage of the optical system to acquire a plurality of images of the test target from the image beam corresponding to a plurality of values of defocus;
calculating from each image a plurality of Edge Spread Functions at a plurality of locations within the test target;
constructing a plurality of Point Spread Function models from the respective Edge Spread Functions;
based on the Point Spread Function models, calculating a plurality of imaging performance values corresponding to the plurality of locations, wherein the imaging performance values are based on a metric selected from the group consisting of: Ensquared Energy; Encircled Energy; and Strehl ratio;
producing one or more maps of imaging performance based on a combination of the imaging performance values; and
comparing two or more of the maps to provide at least one of:
a measure of relative alignment of a focal plane of each imaging device relative to the object plane;
a measure of relative alignment of each imaging device relative to each other.
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