MEASURING DEVICE FOR DISPLACEMENT

PURPOSE:To measure the rates of displacement at multiple points simultaneously with a light source, by disposing beam splitters so as to utilize the reflected light by the beam splitters as measuring light and to transmit the beam through the same to the next photodetector. CONSTITUTION:The beam transmitted through a beam splitter 12 is directed to the photodetector for measuring the next point through a measuring system consisting of a beam splitter 2 which reflects a part of the beam of a light source 1 generating the beam serving as a reference, a condenser lens 6 and a detector 9, a beam splitter 3 which reflects a part of the beam transmitted through the splitter 2, a varying density plate 4, a condenser lens 7 and a detector 10, and the beam splitter 12 which reflects a part of the beam transmitted through the splitter 3, a varying density plate 5, a condenser lens 8 and a detector 11. Therefore, the plates 4 and 5 are mounted with deviation by 90 deg. from the case in which measurement is made at only one point.