| 摘要 |
PURPOSE:To measure the quantity of displacement of parallel movement accurately and easily by using a reflector made of a conic mirror whose vertical angle is 90 deg.. CONSTITUTION:The detecting device consists of a light emitting body 1, the reflecting body 2 made of the conic mirror whose vertical angle is 90 deg., and a photodetecting body 3, and a beam emitted by the light emitting body 1 is incident as incident light on the reflecting body 2 and reflected to reach the photodetecting body 3 as reflected light 5. At this time, the incident light 4 is at right angles to the direction of the displacement of parallel movement to be measured. In this constitution, when a body to be measured, i.e. the reflecting body 2 is displaced by DELTAx and DELTAy in the x-axial direction and y-axial direction crossing the incident light 4 at right angles, the arrival position of the reflected light 5 at the photodetection body 3 shift by 2DELTAx and 2DELTAy and the quantity of displacement of parallel movement of the body to be measured is measured. Even if the DELTAx and DELTAy parallel movement displacement of the body to be measured causes displacement except in the x-axial and y-axial directions, i.e. tilt displacement, there is no influence exerted upon the arrival position of the reflected light 5 at the photodetecting body 3. The reflected light 5 is parallel to the incident light 4 all the time, so angle corrections need not be made. |
