| 摘要 |
<p>PURPOSE:To improve S/N in spectroscopic measurement in an infrared region by casting the light which is cast on a diffraction grating at a large incident angle and diffracted, into the surface of a sample wherein a plane including the normal line on the sample surface and the incident light for the sample becomes orthogonal with respect to a plane including the normal line on the surface of the diffraction grating and the diffracted light at a large incident angle. CONSTITUTION:The light through an incident slit 1 is cast on a diffraction grating G at a large incident angle through a spherical mirror 2. The parallel luminous flux which is diffracted in the grating G is condensed in an output slit 3 through the spherical mirror 2 and a plane mirror 4. Then, the monochromatic light emitted from the slit 3 is cast on a sample S at a large incident angle phi. Here, the diffracted light is the S-polarized light with respect to the grating G. Therefore, the direction of an electric field is orthogonal to the surface of the paper. The light is the P-polarized light with respect to the sample S. The reflected light from the sample S is received with a photodetector 5 using PbS. The PbS has the high sensitivity in an infrared region, and the S/N in the spectroscopic measurement in the infrared region can be improved.</p> |
