| 摘要 |
A bi-focal or multi-focal lens element or blank (14) of synthetic plastics material which is supported by a lens location block (22) releasably moulded on to the front face (16) of the lens element or blank, the material of the block (22) being a comparatively inexpensive non-metallic material so that the block (22) can be thrown away after the lens element or blank (14) has been released from the block. |
