| 摘要 |
PURPOSE:To simplify a circuit and reduce a decision time by a method wherein respective shapes of two subjects are optically picked up to be converted to electric signals, and brightnesses of individual points are compared with each other for comparative decision of identity. CONSTITUTION:Two subjects are each divided into fine points on the same standard, the divided points are scanned in turn on the same standard, and brightness of each scanned point is converted to an electric signal in proportion to the brightness. A set of electric signals for one subject may be previously stored in any one of various mechanical, electronic and optical store means such as video tapes and then reproduced at the time when obtaining a set of electric signals for the other subject. Each pair of two electric signals are applied to a differential circuit to produce the difference therebetween, and the absolute value of the difference is obtained. Voltage corresponding to the degree of disagreement is output through a rectifying circuit 1, while 0V is output upon agreement. |
