| 摘要 |
PURPOSE:To secure flatness and to precisely transfer the shape of a fitting part by forming the surface of a cavity for molding a mirror surface into the mirror surface and forming the surface for molding the rear into a roughened surface and forming the surface of the cavity becoming the reference plane of a holding means into the roughened surface and forming the surface becoming the rear into a smooth surface. CONSTITUTION:A molded body 1 is molded by an injection mold and the surface (a) of the molded body 1 is formed into an optical mirror surface. The fitting parts 2, 2' are formed to the upper parts of both edge side parts of the mirror surface part (a). The rear of the molded body 1 is formed into a roughened surface (b). The surfaces in the stepped parts of the fitting parts 2, 2' are formed into the same roughened surface as the rear (b). The rear side is formed into a smooth surface (c). When molten resin 3 is introduced into the forming molds 4, 5 and molded without thoroughly exerting the dwelling pressure, the adhesive force of molten resin 3 on the surface of the cavity is made weaker in the roughened surface side in comparison with the mirror surface side. Therefore sinks are concentrated in the roughened surface. On the other hand, in the terminals of the fitting parts 2, 2', sinks are concentrated in the part of the mirror surface (a) side. The mirror surface part secures the high-precision flatness free from sinks. The shape of the fitting part can be transferred and formed at high precision. |
