| 摘要 |
PURPOSE:To polish the surface of a work into a specular surface with high flatness and without distortion even if it has a large aperture by specifying a ratio of width dimension of a recessed part to width dimension of a protruded part as well as specifying depth of the recessed part of irregularity formed on the upper surface of a polishing plate. CONSTITUTION:By rotating a polishing plate 3, supplying a polishing liquid 6 on it, floating a work W by fluid pressure of the polishing liquid 6 and rotating and oscillating the work W, the surface of the work W is polished without contact. On the upper surface of the polishing plate 3, a groove is formed spiral by diamond machining. A ratio of width dimension of the recessed and protruded parts 7, 8 formed on the upper surface of this polishing plate 3 is set as 1:0.8-1:1.2, and the depth of the recessed part 7 is set as 0.2-0.3mm respectively. Consequently, it is possible to polish the surface of a work with large aperture into a specular surface with high flatness and without distortion. |
