Method and apparatus for rapid automatic focusing an image of an object.

摘要

An automatic focusing system comprises a lens system or assembly (11) which is fixed in its location along an optical axis (17) between an object (1) and its image (19). The focusing of the object (1), which may vary its position along the optical axis (17), occurs through adjusting a detector or moving an imager (13) to the position in image space where the image space is focused on its image plane (19). The system is structured to facilitate this focusing in an automatic and very rapid manner to accommodate rapid changes in the location of the object (1) along the optical axis (17), e.g. in bar code reading systems.