| 摘要 |
PURPOSE:To detect the quantity of deviation between a pitch angle and an azimuth angle of an optical axis of a photodetection part and the optical axis by providing translucent two-dimensional semiconductor position detectors to the photodetection part. CONSTITUTION:Laser beams L projected from a projector 5 are made incident on the position T of the two-dimensional semiconductor detector 4 provided at the focal position via a condenser lens 3 through the position S of the two-dimensional semiconductor detector 2. A light generating electric current is generated on the position S by a photoelectric conversion action of a semiconductor layer and the electric current is divided in an inversely proportional state to each resistance between the position S and electrodes 25a and 25b and further, divided in an inversely proportional state to each resistance between the electrodes 26a and 26b. The divided electric currents IX11, IX12, IY11 and IY12 are inputted to a CPU via an input circuit and the CPU performs the prescribed arithmetic operation and calculates the position S(X1, Y1). This shows the quantity X1 of lateral deviation and the quantity Y1 of longitudinal deviation of the optical axis J with respect to the beams (L). Next, the position T(X2, Y2) is calculated in the same way. Then, the prescribed arithmetic operation is performed based on the coordinates (X2, Y2) and the azimuth angle and the pitch angle of the photodetection part 1 with respect to the optical axis (J) can be calculated. |
