| 摘要 |
PURPOSE:To coincide with axis of a rotary shaft with the optical axis of a lens to be machined and to enable stable machining of the lens having an accurate axis, by a method wherein the lens to be machined is nipped between a pair of jigs positioned facing each other, and centering is effected by means of the flow force of fluid coming out from between the jig and the lens. CONSTITUTION:After a distance between a tip jig 18 of a clamp shaft 4 and a tip jig 17 of a rotary shaft 1 is situated in a given position, the shafts 1 and 4 are rotated at a low speed in linkage with each other. A lens 21 to be machined, simultaneously, is brought between the jigs 17 and 18 through mechanical or manual operation, and a pinion 8 is rotated counter clockwise to move the shaft 4 leftwardly. The lens 21 is nipped at a low pressure, and fluid is injected against the surface of the lens 21 through flow holes 19 and 20 of the shafts 1 and 4 to bring the lens 21 into a hollow state. Namely, gaps 22-25 are provided between the jigs 17 and 18 by means of compressed fluid, and since the compressed fluid comes out through the gaps, a static bearing action is rendered effective, a friction force between the jigs 17 and 18 and the both surfaces of the lens 21 is extremely reduced, and high-precise centering can be effected. |
