Optical path equalizer

摘要

An optical system for adjusting the optical path between a detector and an object, such as an information-encoded label affixed to a package. The optical system comprises a pair of movable mirrors and an array of fixed mirrors. One of the movable mirrors is positionable to direct an image reflected from the object to any one of the array of fixed mirrors. The other of the movable mirrors is positionable to direct the image reflected by the fixed mirror to the detector. The positions of the movable mirrors are adjusted responsive to variations in the measured height of different objects.