ANDed motor control system for motorized ophthalmic instrument

Patent 4496226 Issued on January 29, 1985. Estimated Expiration Date:

January 29, 2002. 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.

Abstract Claims Description Full Text

Patent References

3860330

Angle coder with variable input angle Patent #: 4240069
Issued on: 12/16/1980
Inventor: Hullein , et al.

Inventors

Assignee

Bausch & Lomb Incorporated

Application

No. 06/285717 filed on 07/22/1981

US Classes:

351/234, Mounted on rotatable disc351/235Having plural disc carrier

Examiners

Primary: Corbin, John K.
Assistant: Dzierzynski, Paul M.

Attorney, Agent or Firm

International Class

A61B 3/02 (20060101)

Abstract

An improved refractor for use in the subjective examination of human eyes. Each half of the refractor includes a plurality of lens supporting disks, a hub assembly for rotatably supporting the disks, and a comb assembly to space the disks along the optical axis. One of the disks supports at least one set of 4 cross cylinder lenses. Each disk is coupled to a stepping motor for selective rotation. Each motor is, in turn, supported by a bracket which permits rotation equivalent to a partial motor step to insure alignment of the optical elements supported on the disks with the optical axis. The cylinder lenses supported on the disks are also rotated by a stepping motor. The Risley prisms of each half of the refractor are always positioned on the optical axis and rotated by stepping motors. Finally, the refractor includes electronics, including a microprocessor, to control the rotation of the motors as required to move the various optical components as necessary to emulate the ophthalmic prescription of the person whose eyes are being examined.