センサアレイによる複数スポット光位置の高速同時検出法

抄録

The applications using the optical measurement systems often require the measurement performance to be fast, of high accuracy, and capable of simultaneously detecting plural points. In this paper, a new method has been developed to measure the positions of plural light spots in a continuous manner using a sensor array, which consists of plural sensor elements. The basic principle of the method detects the sensor elements that generate the peak values by comparing the outputs of the sensor elements with the standard voltage, and then measures the actual peak positions with the use of an analog interpolation. This method is different from others in that it uses an analog processor for peak detection and calculation algorithm. The method allows the simultaneous processing of the peak detection and the calculation of the interpolation. As a result, this method can meet three requirements that are often required of this kind of measuring system: (1) high-speed measurement, (2) high-accuracy performance, and (3) simultaneous measurement of plural points. We have designed and built a prototype position sensor system that implements the proposed method. The experimental results are as follows: (1) the resolution of 1μm or less; (2) the sampling time is 6μs/point; (3) simultaneous measurement of 4 points.