DETECTOR FOR LIGHT TRANSMITTING POSITION COORDINATES

摘要

PURPOSE:To increase the intensity of the light reaching the edge surface of a light transmitting guide path and at the same time to improve the S/N, by forming numbers of through holes to a transparent plate and impregnating a fluorescent matter into he transparent plate to obtain light transmitting guide paths which cross each other in a lattice form. CONSTITUTION:A light transmitting guide path plate 5 contains numbers of through holes 1 to form light transmitting guide paths 2a and 2b which is impregnated with a fluorescent matter and cross each other in the form of a lattice. The fluorescent matter containing a rare earth metal and contained in the paths 2a and 2b is excited by the light of a light pen 3 and emits the light. This light propagates into the excited upper and lower paths 2a and 2b to reach the edge surface of these guide paths. The photodetector 4 provided on the edge surfaces of the paths 2a and 2b detect the optical intensity on the edge surfaces of the paths 2a and 2b. In such way, the excited paths 2a and 2b are detected by discriminating the detector 4 that detected the emitted light. Thus the position coordinates of the pen 3 can be detected.