| 摘要 |
<p>PURPOSE: A displacement detecting device is provided to controls heat generated when using the device, and to reduce a service condition. CONSTITUTION: A displacement detecting device(1) comprises a light source(2), a beam splitting unit(3), a diffraction grating(4), a reflecting body(6), a beam joining unit, a light receiving part(8), and a relative position information output unit(10). The beam splitting unit splits lights emitted by the light source into a first beam becoming incident into a target measurement member and a second beam utilized as reference lights. The diffraction grating is split by the beam splitting unit, diffracts the first beam reflected by a target measurement surface of the target measurement member, and makes the diffracted first beam incident into the target measurement surface of the target measurement member again. The reflecting unit reflects the second beam split by the light splitting unit. The beam joining unit mutually overlaps the first beam diffracted by the diffracting grating and reflected by the measurement surface again and the second beam reflected by the reflecting unit. The light receiving unit receives the coherent lights of the first and second beams overlapped by the beam joining unit. [Reference numerals] (10) Relative position information output unit</p> |
