| 摘要 |
<P>PROBLEM TO BE SOLVED: To achieve a spectral instrument for optical spectrum analysis using, even for measurement light of different wavelength ranges such as C band and L band, one and the same prism by installing a rotatable mirror outside the surface facing a diffraction grating of a prism and adjusting the angle of the mirror. <P>SOLUTION: The spectral instrument performs wavelength dispersion of the measurement light with a prism, receives the wavelength dispersed light with a light receiving part, and analyzes the optical spectrum of the measurement light, and the prism has an incidence surface where the measurement light is made incident and a diffraction grating surface adjacent to the incidence surface. In the spectral instrument, a mirror rotatable at an arbitrary angle is provided near the outside of the surface facing the diffraction grating surface. The measurement light made incident from the incidence surface of the prism is wavelength dispersed by the diffraction grating surface, emitted from the surface facing the diffraction grating surface, reflected by the mirror and made incident from the surface facing the diffraction grating surface, wavelength dispersed again by the diffraction grating surface, emitted from the incidence surface, and received by the light receiving part. <P>COPYRIGHT: (C)2012,JPO&INPIT |
