| 摘要 |
Position detection apparatus, insensitive to a tilt of the object surface, comprises: an incident unit that forms a parallel beam from a light beam of a light source (101) and supplies the parallel beam to a beam splitter (113) in a way that the separated beams, obtained from the collimated beam by the beam splitter (113), are respectively incident upon the reference surface (122) and the measurement target surface (121) at an angle; and a reflection unit (114) that reflects the probe beam, which has been reflected by the measurement target surface (121). A signal is generated, corresponding to a phase difference of the separated beams by interfering a light beam that has been supplied from the reflection unit (114), separated by the beam splitter (113), reflected by the reference surface (122) and the measurement target surface (121), and integrated again to a light path by the beam splitter (113). |
