| 摘要 |
PURPOSE:To obtain the absolute slant amount of the optical axis of a spherical mirror surface with respect to the bottom surface from the slant amounts of both optical axes, by measuring the slant amounts of the spherical mirror surface of a metal piece and the bottom surface of the metal piece, which is finished into a mirror surface, by optical systems. CONSTITUTION:In parallel with the measurement of the slant amount of the optical axis of a spherical mirror surface 7a by an optical system 40, the slant amount of the optical axis of a bottom surface 7c is measured by an optical system 50. Based on the slant amounts of the optical axes, the slant amount of the optical axis of the spherical mirror surface 7a with respect to the bottom surface 7c, which is to become a reference, computed. Laser light from a laser tube 31 is projected on the bottom surface 7c as a reticle image through a beam splitter 32, mirrors 42 and 43, a lens 44, a reticle 45 and a beam splitter 47. The image of the reflected light from the bottom surface 7c is formed on an area sensor 49 through the beam splitter 47 and a lens 48. A metal piece 7 is rotated, and the central position of the rotating image is obtained by computation from a locus Tc in a sensor 49. Thus, the absolute slant amount of the optical axis of the spherical surface 7a with respect to the bottom surface 7c including the directivity can be readily obtained highly accurately. |
