OPTICAL SYSTEM FOR HIGH-SENSITIVITY REFLECTION MEASURING APPARATUS

摘要

PURPOSE: To obtain an optical system, for a high-sensitivity reflection measuring apparatus, which enhances the utilization rate of light, whose constitution is simple, whose manufacturing process is simplified and whose cost is reduced. ;CONSTITUTION: An aspherical concave mirror 10 in which a prescribed range in the central part is opened, which has one focal point F1 on the side more outside than the edge of at least the opening and in which a sample 12 is placed in the position of the focal point F1 is used. Then, the region width of a mirror face from the end of the opening is set at a region width in which reflected light of light incident on the mirror face from a proper light-source position can be made incident on the sample 12 within a range of 60°≤θ90° (θ=angle of incidence), incident light is reflected by the aspherical concave mirror and the face of the sample, and it is reflected again by the concave mirror 10 and becomes the radiant light for detection. Thereby, light can be made incident on the sample properly and with good efficiency by an extremely simple constitution. That is to say, only the aspherical concave mirror can be used as the main element, effective light can be used in a high ratio, and the accuracy of a detection can be enhanced.;COPYRIGHT: (C)1995,JPO