Mark Roberts wrote: >Stan Halpin wrote: > >>There was an item in the newspaper today - Dow Corning has been working with >>an NGO on ways to reduce the many problems associated with poor vision and >>lack of access to prescription corrective glasses. So they have been testing >>a prototype of a "self-adjustable" lens. A person puts on the glasses, >>manipulates what sounds like a form of pump to adjust the amount of an >>"optical silicone fluid" in the lens to adjust the power of the lens. The >>adjuster can then be detached and the user has what look like a normal pair >>of glasses. >> >>My mind is boggled! >> >>I wonder if optical silicone fluid would be lighter than, for example, HD >>glass in modern camera lenses? And how about a hydraulic adjustment to zoom >>rather than via mechanical motors and gears? > >I remember reading on the PDML about 10 years ago about a patent for >that kind of thing... by Pentax.
Actually, now that I think about it the Pentax patent was relating to a lens that focused by electronically changing the shape of one or more of its elements (via a piezoelectric effect, IIRC). -- Mark Roberts - Photography & Multimedia www.robertstech.com -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
