摘要 |
A variable focus lens comprises first and second transparent, flexible membranes (2) which are tensioned and which define a cavity (30) in which a transparent, silicone oil (4) is sealed. Adjustment of the pressure or volume of the oil in the cavity changes the focal length of the lens. To fabricate the lens, the periphery of each membrane (2) is engaged between two rings (8, 10; 10, 12) of a set of three interengaging rings (8, 10, 12). The interengaged rings are crimped together to tension the membranes (2) and seal the cavity (30). |