| 摘要 |
PURPOSE:To measure exactly the information on the one-dimensional position of an image by subjecting the output signal from a line sensor to binary coding, counting the number of high photodetection parts in a counter circuit and changing the set value of the counter circuit in accordance with the count result thereof. CONSTITUTION:An operation start signal SE is outputted from a microcomputer 11 to a comparator 5 through the 3rd latch circuit 12. On the other hand, the line sensor 3 converts incident light to a detection signal SA and the amplified detection signal SB is outputted to the circuit 5. The signal SB is subjected to binary coding in the circuit 5 and the binary-coded signal SC is outputted to the 1st and 2nd gate circuits 6, 7 and a counter circuit 13. A latch signal SH is outputted to the 1st latch circuit 9 in synchronization with the rise at the leading edge of the part P1 of the signal SC in the circuit 6. A latch signal SI is outputted to the 2nd latch circuit 10 in synchronization with the fall at the rear edge of the part P1 of the signal SC in the circuit 7. The circuits 9, 10 output the address signals SD1, SD2 corresponding to the front edge and rear edge of the latched part P1 to the computer 11. |
