| 摘要 |
PURPOSE:To make it possible to simply determine the reference position of a moving mirror, by forming the moving mirror and fixed mirror of a Michelson interferometer into a concaved mirror of roof shape to parallelly move incident light and emitted light and detecting light returning to a light source side by an auxiliary interferometer other than a main interferrometer. CONSTITUTION:A Michelson interferometer is constituted of a light source S, a moving mirror 1, a fixed mirror 2 and a beam splitter 3. The moving and fixed mirrors 1, 2 are formed into a concaved mirror roof shape and move incident light and emitted light in parallel. The light emitted from the light source S and passed through a specimen 4 enters not only a main interferometer 1 through a fixed pathway of (a), (f), (g), (e) but also a main interferometer D1 through a variable pathway of (a), (b), (c), (d), (e). Other than the above mentioned pathways, the light from the light source S is inputted to an auxiliary interferometer D2 through two light paths of (a), (f), (d), (h) and (a), (b), (c), (d), (h). When the lengths of two light paths of the main interferometer D1 are equal, the lengths of the light paths to the auxiliary interferometer D2 also become equal. By this mechanism, the position mark signal of the moving mirror to the light path difference between two light paths of the main interferometer is easily calculated by the max. peak obtained by the auxiliary interferometer D2. |
