OPTICAL SENSOR

摘要

A sensor (10) for determining the position of a moveable surface having patterned regions (7, 8) of high and low reflectivity to EMR. The sensor comprises an ASIC (22), at least one lens, and at least one EMR source (16). The ASIC comprises at least one array of EMR sensitive detectors and processing means. The EMR source facilitates illumination of the surface and the at least one lens (19) facilitates the focusing of reflected EMR from the surface and generates an image on the at least one array of EMR sensitive detectors corresponding to the pattern on the surface. The ASIC, the at least one lens, and the at least one EMR source are all enclosed in a single housing (15) providing accurate optical alignment of these elements and integrated as a single replaceable module. The processing means of the ASIC facilitates processing of the image to determine the position of the pattern on the surface.