| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a spectroscopic unit that can stabilize formation of diffraction grating patterns.SOLUTION: A spectroscopic unit 4 that both splits and reflects light from one side comprises a diffraction layer 6 formed along the curved face of the body, a flange 7 formed integrally along the periphery of the diffraction layer 6 to be thicker than the diffraction layer, and a reflective layer 8 formed over the diffraction layer. In the diffraction layer 6, a diffraction grating pattern 9 is formed toward a prescribed side relative to the center of the diffraction layer 6 when viewed from the other side.</p> |
