| 摘要 |
PURPOSE:To measure dimensions by accuracy exceeding the resolution decided by a pitch of a photodiode array, by forming a video signal which connects peak-to-peak values of a stepwise video signal. CONSTITUTION:A photodiode array 2 detects bright and dark signals by a clock signal generator 3 and a driving circuit 4, and outputs a stepwise video signal from a reading-out circuit 6. This video signal is formed to a video signal whose peak-to-peak values are connected by a connecting circuit 7. Subsequently, the video signal smoothed in this way is binary-coded at a prescribed slice level by a binary-coding circuit 9. This binary-coded signal is read out by frequency of an oscillator 14 for oscillating the frequency which is higher than that of the clock signal generator 3. In this way, dimensions can be measured by accuracy exceeding the resolution decided by a pitch of the photodiode array. |
