Patent ID: 7847953
Filing Date: 2010-12-07
Classification: G01B,G01Q

Abstract:
1. A homodyne laser interferometer probe, comprising: (a) an optical fiber for guiding light; (b) a collimator lens that receives the light from the optical fiber; (c) a ¼ wavelength plate that receives the light from the collimator lens and converts the light from linearly polarized light to circularly polarized light; (d) a beam splitter for dividing the light from the ¼ wavelength plate into reference light and measurement light; (e) a first focal lens that receives the reference light from the beam splitter; (f) a reflection mirror for reflecting the reference light from the first focal lens; (g) an adjustment mechanism that is placed between the first focal lens and the beam splitter and that adjusts a distance between the first focal lens and the beam splitter while keeping constant a distance between the first focal lens that receives the reference light from the beam splitter and the reflection mirror that receives the reference light from the first focal lens and reflects the reference light; (h) a second focal lens that receives the measurement light from the beam splitter; and (i) a probe body that integrally incorporates therein the collimator lens, the ¼ wavelength plate, the beam splitter, the first focal lens, the reflection mirror, the second focal lens, and the adjustment mechanism, wherein the reference light from the reflection mirror is returned to measurement means along the same route, and wherein the measurement light from the second focal lens is applied to a measurement object and the measurement light from the measurement object is returned to the measurement means along the same route.