| 摘要 |
PURPOSE:To avoid the effect of the fluctuation of the scanning speed, by giving correction to the fluctuation of the input signal level which is caused by the fluctuation of one scanning time of the hand scanner. CONSTITUTION:Reference clock CP is supplied to counter 62 and controller 66. With supply of start pulse ST to controller 66, controller 66 produces the latch signal to make latch circuit 63 accept the contents of counter 62, and then clears the contents of counter 62 in the timing of the next clock CP. Counter 62 counts the next input of clock CP. The contents of circuit 63 is about the storage time and held until the start of the next scanning. Accordingly, the count number of circuit 63 is supplied to code converter 64 to generate the reciprocal signal which is reversely proportional to the count number. The reciprocal signal is converted into the analog reciprocal signal D/A converter 65 to be supplied to the other input terminal of analog multiplier 61. Thus for the output of multiplier 61, the corrected normal signal VON is obtained. |
