| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a spectroscopic instrument using transmission gratings capable of improving both of wavelength resolution and diffraction efficiency, and reducing reflection loss, and to provide a detector and a method for manufacturing the spectroscopic instrument. <P>SOLUTION: A spectroscopic instrument includes a transmission grating for transmitting incident light. The transmission grating has a plurality of projections 110 which periodically project from a base material 100 along a first direction X. The plurality of projections have inclined planes 140, and the inclined plane inclines to a base line, which is perpendicular to the base material. When an incident angle of incident light to the transmission grating is considered as an angle α to the base line, and a diffraction angle of diffracted light is considered as an angle β to the base line, the incident angle α is the one smaller than Bragg angle θ to the inclined planes, the diffraction angle β is the one larger than Bragg angle θ. Each of the plurality of projections has first antireflection structure 150 (160) in which a projection height from the base material reaching to an interface between each of the plurality of projections and the air is different as distance in the first direction from the inclined planes is different. <P>COPYRIGHT: (C)2013,JPO&INPIT |
