A symbol read device which has separate gain controls for reading different scan lines. The symbol read device includes a light beam emitter, a scanner which scans the light beam over different positions on a symbol surface having a symbol to be read, a detector which detects light reflected from the...http://www.google.de/patents/US5288983?utm_source=gb-gplus-sharePatent US5288983 - Symbol read device having separate gain controls for reading different scan lines
