Microscope auto-focus module comprises beam conditioners for use with a measurement light bundle that is transmitted as a divergent, eccentric annular beam towards the examination object and then reflected from it

摘要

Auto-focus module (30) for a microscope based system (1) has a light source (31) for generating a measurement light bundle (32). A first axial beam conditioner (35a) generates an eccentric, annular divergent measurement light beam (32a), while a second axial beam conditioner (35b) is provided to make the re-emitted divergent light beam (32b) parallel. A differential diode (42) within the auto-focus module is provided for determination of the focal length.