White-light interferometric measuring device

摘要

A white-light interferometric measuring device includes: a white light source that emits a white light beam; a beam splitter that reflects the white light beam; and an interference objective lens that collects the white light beam having reflected off the beam splitter in the direction of an optical axis and irradiates a measurement workpiece with the white light beam, the interference objective lens generating interference between a measurement light beam obtained by reflection of the white light beam off the measurement workpiece and a reference light beam obtained by branching of the white light beam to be converged on the measurement workpiece. Polarization correcting means that corrects the white light beam to enter the interference objective lens to circularly polarized light is arranged between the white light source and the interference objective lens.

主权项

1. A white-light interferometric measuring device comprising:
a white light source that emits a white light beam; a beam splitter that reflects the white light beam; an interference objective lens that collects the white light beam having reflected off the beam splitter in a direction of an optical axis and irradiates a measurement workpiece with the white light beam, the interference objective lens generating interference between a measurement light beam obtained by reflection of the white light beam off the measurement workpiece and a reference light beam obtained by branching of the white light beam to be converged on the measurement workpiece; and a polarization corrector that corrects the white light beam to enter the interference objective lens to circularly polarized light, the polarization corrector being arranged between the white light source and the interference objective lens, wherein the polarization corrector includes the beam splitter having a reflection surface for the white light beam, a dielectric film provided on the reflection surface of the beam splitter for reflection of the white light beam, a polarizing plate positioned between the white light source and the beam splitter, and a quarter-wave plate positioned between the beam splitter and the interference objective lens.