| 摘要 |
PURPOSE:To lower the stray light level and to increase the spectrosensitivity, by making different the heights of inlet and outlet slits and providing the light absorbing means around the both sides of the outlet slit. CONSTITUTION:The inlet slit S1 and the outlet slit S2 are located by separating them at upper and lower side of the plane F through tilted line tying the center. The plane F is the plane vertical to the rotating axis A of the grating G, passing through the center of the diffractive grating G. Further, both sides of the outlet slit S2 are provided with the light absorbing wall w of black and coarse surface. Thus, the reflection light R by the grating G of the incident light I to the grating G, and the diffraction light D' having different number of order different in the sign with the diffractive light used for the photometry are incident with almost the same height as the outlet slit S2, and the reflection light on the wall is reincident to the grating G, and after reflection or diffraction, it is incident to the spectrometer wall with almost the same height as the inlet slit S1, allowing almost zero level of stray light. Thus, the spectrosensitivity can be increased. |
