Crossed cylinder lenses refractor with three-lens variable crossed cylinder assembly and method of use
Patent 4840479 Issued on June 20, 1989. Estimated Expiration Date: 
November 2, 2007. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
November 2, 2007. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesInventorApplicationNo. 07/116322 filed on 11/02/1987US Classes:351/235, Having plural disc carrier351/234Mounted on rotatable discExaminersPrimary: Bovernick, Rodney B.Attorney, Agent or FirmInternational ClassesA61B 3/028 (20060101)A61B 3/036 (20060101) A61B 3/02 (20060101) AbstractA new lens system and method of use for otherwise conventional refractors comprising a synchronized, three-lens, variable crossed cylinder lens attachment and selectable fixed crossed cylinders which may be placed in the examining optical path. The synchronized, variable crossed cylinder lens attachment replaces the Jackson crossed cylinder lens and rotates in step with rotation of the cylinder lens axis. Batteries of strong and weak crossed cylinder lenses replace the strong and weak cylinder lenses of conventional refractors. Refractive techniques utilizing the disclosed crossed cylinder lens systems are also described.Other References
Field of SearchLens or filter selectively insertable in optical pathMounted on rotatable disc Having plural disc carrier Methods of use Including lens selectively insertable in optical path On rotary disc Hand held type Including trial frame With multifocal lens With plural lens carrier With individual lens holder Removably attachable to eye glass frame | |
