Patent EA-001165-B1 (EA)
Title: Variable focus lens by small changes of the equatorial lens diameter
Inventor: SCHACHAR RONALD
IPC: G02B26/08
Filed: 1996-05-10
Abstract: 1. A variable focus lens comprising a synthetic elastically deformable lens body comprising two transparent webs intersecting an optical axis and meeting in an elastically expandable periphery wherein said lens is provided with an expanding means, said expanding means applies radially outward directed forces immediately to said periphery of said lens symmetrically to said optical axis. 2. The variable focus lens of claim 1 wherein said webs are comprised of a synthetic polymer. 3. The variable focus lens of claim 2 wherein said synthetic polymer is selected from the group consisting of poly(ethylene terephthalate), poly(methyl methacrylate), polyethylene, polypropylene, polyvinyl chloride, poly(tetrafluoroethylene) and silicone resins. 4. The variable focus lens of claim 1 wherein said cavity is filled with a gas. 5. The variable focus lens of claim 4 wherein said gas is selected from the group consisting of air, carbon dioxide, helium, neon, argon, krypton, xenon and sulfur hexafluoride. 6. The variable focus lens of claim 1 wherein said cavity is filled with a liquid. 7. The variable focus lens of claim 6 wherein said liquid is selected from the group consisting of water, aqueous solutions of water-soluble inorganic and organic solids, organic liquids, mixtures of water and water-miscible organic liquids and silicone oils. 8. The variable focus lens of claim 7 wherein said aqueous solution is selected from the group consisting of solutions of water-soluble inorganic salts having halogen anions. 9. The variable focus lens of claim 7 wherein said organic liquid is selected from the group consisting of hydrocarbons, halogen substituted hydrocarbons, glycols and polyethylene glycols. 10. The variable focus lens of claim 7 wherein said mixture of water and a water-miscible organic liquid is selected from the group consisting of mixtures of water with glycols or polyethylene glycols. 11. The variable focus lens of claim 7 wherein said liquid is a silicone oil. 12. The variable focus lens of claim 1 wherein said tension means comprises screws oriented radially outward from said optical axis. 13. The variable focus lens of claim 1 wherein said tension means comprises solenoids oriented radially outward from said optical axis. 14. The variable focus lens of claim 1 wherein said tension means comprises hydraulic cylinders oriented radially outward from said optical axis. 15. The variable focus lens of claim 1 wherein said tension means comprises pneumatic cylinders oriented radially outward from said optical axis. 16. The variable focus lens of claim 1 wherein said tension means comprises at least one cam and cam follower. 17. The variable focus lens of claim 1 wherein said tension means for exerting tension on said periphery in a radially outward direction comprises means for exerting tension in a direction other than radially outward operatively coupled to means for redirecting said tension to act radially outward on said periphery. 18. The variable focus lens of claim 17 wherein said means for exerting tension in a direction other than radially outward is selected from the group consisting of screws, solenoids, hydraulic cylinders, pneumatic cylinders, cams and cam followers. 19. The variable focus lens of claim 17 wherein said means for redirecting said tension to act radially outward on said periphery is selected from the group consisting of tendons working over pulleys, cranks, and a peripheral flange integral with said lens and an anvil. 20. The variable focus lens of claim 1 wherein said expanding means comprises an expandable ring coupled to said periphery. 21. The variable focus lens of claim 20 wherein said ring is embedded in said lens body adjacent to said periphery. 22. A method for increasing the optical power of an elastically deformable lens of any preceding claim wherein said periphery is expanded by an amount not exceeding 5 % of said relaxed equatorial lens diameter.