THREE-DIMENSIONAL TILT SENSOR AND METHOD OF MEASURING ANGULAR DISPLACEMENT OF MEASURED OBJECT ON THREE AXES USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a measuring device (three-dimensional tilt sensor) and a measuring method capable of optically measuring angular displacement (rotation) of a measured object on mutually orthogonal X and Y axes set on a surface of the measured object and a Z axis orthogonal thereto and perpendicular to the surface of the measured object.SOLUTION: A three-dimensional tilt sensor 100 consists of a light source 110 for measurement, a collimator lens 120, first and second measurement optical systems 150 and 160, a half-mirror 130, and a dedicated target 140 consisting of a diffraction grating provided to the measured object. The first measurement optical system 150 irradiates a surface of the dedicated target with measurement light at right angles so as to measure angular displacement on the X axis and Y axis set on the dedicated target 140 based upon reflected light, and the second measurement optical system 160 measures angular displacement on the Z axis perpendicular to the X and Y axes set on the dedicated target based upon primary diffracted light generated by irradiating the surface of the dedicated target with the measurement light at right angles.SELECTED DRAWING: Figure 1