Patent ID: 6426509
Filing Date: 2002-07-30
Classification: G07D

Abstract:
An optical paper sheet checking apparatus comprising:a plurality of optical sensors which output signals obtained by optically detecting a pattern of a paper sheet, the optical sensors comprising light emitting elements and light-receiving elements; a driving unit which supplies a current to said light emitting elements in said plurality of optical sensors in accordance with a control signal; and a controlling unit which, while said paper sheet is not in a predetermined position, (a) supplies a maximum current having a predetermined value to said light emitting elements and thereafter supplies said control signal to said driving unit so as to decrease the supply of current, (b) determines and stores optimum values for each of said plurality of optical sensors, each of said optimum values being a value of current being supplied when the output voltage of said light-receiving elements has changed by a predetermined value relative to a value of said output voltage said maximum current, (c) when said paper sheet is at said predetermined position, supplies said control signal to said driving unit based on each of said optimum values which have been stored, (d) selectively extracts said detected signals from said optical sensors and outputs detected data representing the pattern of said paper sheet.