Optical component focus testing apparatus and method

摘要

An optical component focus testing apparatus includes a plurality of test pattern displays. One or more illuminators are configured to selectively illuminate different test pattern displays at different times. Light directors are provided to direct light from at least one of the illuminated test pattern displays towards an optical component under test. The light directors and test pattern displays are arranged such that, in use, light directed from different illuminated test pattern displays travel different distances to reach the optical component under test.