| 摘要 |
PURPOSE:To remove higher-order diffracted light or stray light and to improve the accuracy of colorimetry by providing an incident slit to the position where the normal of a concave diffraction grating and Rowland circle come in contact. CONSTITUTION:The incident slit 3 is provided on the position where the Rowland circle 2 and the normal of the concave diffraction grating 1 come in contact and light is guided through the slit 3 to the grating 1 from the outside of the photometric device. Then, the dispersion image generated by said light is imaged on the Rowland circle 2 along the same. Of this light, the primary diffracted light 4 as a short wavelength side is passed through a filter 5 for removing stray light and is detected by a 1st photodetector array 6. The minus 1st order diffracted light 7 which emerges to the side opposite from the diffracted light 4 with the normal of the grating 1 in-between is passed as a long wavelength side through a filter 8 for removing higher-order diffracted light and is detected by the 2nd photodetector array 9. The zero order diffracted light which is the main cause for the stray light passes backward the incident slit 3 and emerges to the outside of the photometric device, since said slit exists on the normal of the grating 1. |
