| 摘要 |
PURPOSE:To measure a shape with high accuracy and also at high speed by measuring and storing a reference surface by a reflection mirror whose reflecting angle is variable, placed on a convex or concave surface of a beam light whose sending-out angle is variable, and deriving a shift to a photodetecting position of a reflected beam light placed at the same position as said mirror. CONSTITUTION:Beam light 22 of a light source 20 which is turnable is focused by a beam splitter 23, a collimating lens 24 and a focusing lens 25, and for instance, a convex wave surface is formed, a reflection mirror 32 whose inclined angle and position are variable is placed at an optional position of its concave wave surface, a detectig signal DS of a photodetector 40 placed at the back side of a splitter 23 is supplied to a controlling circuit 42 provided with a memory 43 through an A/D converter 41, and the light source 20 and the mirror 32 are controlled. First of all, the lens 25 for forming the concave wave surface being near the object surface to be measured is placed, information of a reference surface (a) is derived by making a projecting angle of the light source 20 variable, and placing the mirror 32 at each position on the concave wave surface, and a shape is derived from a position shift against reflected beam light derived by placing an object surface to be measured (b) at the surface (a) position. |
