| 摘要 |
A contact lens button and a block are integrally formed together when the contact lens button is cast in a cup (10) having an aperture (20) formed in the center of the bot- tom wall (14) of the cup. The block has a first elongated end forming a spindle (23) and a second end which is of circular, gen- erally planar configuration. The spindle end is inserted through the aperture in the bottom wall of the cup providing an interference fit with the circular end portion located inside the cup spaced parallel to and slightly up- wardly from the bottom wall, and the first spindle end extends exteriorly of the cup. A quantity of liquid lens material is dispensed into the cup, completely surrounding the cir- cular end portion of the block. The material cures around the block second end, with the formed button and block removable from the cup as a single unit. The block first end is secured to a lathe chuck for rotating the but- ton to cut the concave base surface of the lens. A front curve block is then remov- ably secured to the base curve surface and inserted into a lathe chuck for cutting the convex power curve into the butt on while previously or simultaneously cutting away the block. The block sets the turning axis of the button and assists in transferring th e turning axis over to the front curve block.
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