Character recognition appts. with CCD camera as optical sensor - measures relative speed of camera and object, and adjusts comparison thresholds according to stored digitised video signals

摘要

The character recognition arrangement contains a CCD camera which sequentially scans the field to be read, a device which measures the relative speed between the information carrier and camera and a regulated illumination device. The measured relative speed is used to control switching the camera on and off. The comparison threshold value of the camera is adjusted according to stored values after scanning of the whole field. The camera video signals are stored in digital form. USE/ADVANTAGE - For use in automatic readers. Character recognition device automatically adapts itself to changing ambient conditions.