Patent ID: 7688445
Filing Date: 2010-03-30
Classification: G01J

Abstract:
1. A spectroscope which has a concave diffraction grating which disperses incident light for different wavelengths, an incident light introduction unit which introduces incident light into the concave diffraction grating, and an outgoing light receiving unit which receives outgoing light dispersed for different wavelengths by the concave diffraction grating, the spectroscope comprising: an incident aperture which limits an incident angle of light emitted by the incident light introduction unit to the concave diffraction grating; and an outgoing aperture which limits an outgoing angle of outgoing light dispersed for every wavelength by the concave diffraction grating to the outgoing light receiving unit, wherein the spectroscope is constructed so that relatively rotational transfers of at least two selected from the group consisting of the concave diffraction grating, the incident aperture and the outgoing aperture can be performed along a Rowland circle formed by the concave diffraction grating so as to arrange the incident aperture and the outgoing aperture in a position of maximum diffraction efficiency of the concave diffraction grating on a wavelength of measuring.