The depth of modulation of an analog electrical signal generated by a photodetector during scanning of a bar code symbol in the field of bar code scanning is enhanced under circumstances where the modulation of the analog signal has been degraded, for example, by an oversized sampling aperture in relation...http://www.google.ca/patents/US5140146?utm_source=gb-gplus-sharePatent US5140146 - Bar code symbol reader with modulation enhancement
