| 摘要 |
PURPOSE:To facilitate the design and the adjustment of an optical system which can increase the diameter of a slit for narrowing measured light to a large size. CONSTITUTION:Measured light is obliquely cast into a wedge-shaped coupling prism 11. At this time, a beam sampler 8 is arranged in the inclined state in the reverse direction with respect to the incident surface of the wedge-shaped coupling prism 11 with respect to the optical axis of the measured light. The slant angle, thickness and the refractive index of the beam sampler 8 are set so that the aberration caused by the prism can be compensated. |
