| 摘要 |
PROBLEM TO BE SOLVED: To make an accurate measurement realizable without changing the incidence angle on a sample by using a semiconductor laser where a plurality of laser chips for emitting a different wavelength is packaged in a piece for a light source. SOLUTION: The main ray of three beams emitted from a semiconductor laser 15 enter a collimator lens 17 in parallel with one another, are emitted from the collimator lens 17, and then enter a wavelength dispersion prism 18 while being converged. Three beams 2 emitted from the wavelength dispersion prism 18 become circular polarization beams 4 by a 1/4-wavelength plate 3. In beams through the 1/4-wavelength plate 3, beams 6 of linear polarization constituent are taken out by a polarizer 5, and then elliptic polarization beams 8 are formed by a compensator 7. The beams 8 enter a substrate 11 that is placed on a placement stand 9 at a center with a specific incidence angle. Since the beams with the three wavelengths are set to completely the same light path, the three beams all enter the substrate 11 at the same incidence angle, thus suppressing a measurement error due to the wavelength change of a light source by temperature change or the like.
|
