Apparatus and method for adjustable variable transmissivity polarized eye glasses

Abstract

Adjustable variable transmissivity (AVT) eyewear for patients, the AVT eyewear having a liquid crystal lens driven by an electronics circuit so that light transmitted through the lens is detected, the transmitted light being driven to a setpoint by the electronics circuit according to feedback control on the liquid crystal lens drive voltage duty cycle. In another embodiment, light detected from the ambient is detected and the resulting photocurrent value processed by a microprocessor included in the electronics circuit, the microprocessor driving the liquid crystal lens to a desired transmissivity, the desired transmissivity given by a computed transmissivity curve. The computed transmissivity curve may be controlled by the physician or in an alternate embodiment controlled by the patient according to a set of electronic controls on the AVT eye glasses.

1 . Eye glasses having adjustable variable transmissivity for controlling the amount of light on at least one eye positioned behind said glasses comprising:
 A frame capable of holding lenses and having earpieces rotatably attached to either side;   Two lenses fixed into the frame and having transmissivity controllable by a lens voltage signal connected to the lenses;   A photoelectric light sensor integrated into the frame so as to sense ambient light in a field of view to the front of the eye glasses and producing a measured photocurrent in response to the ambient light,   a light plug having at least two apertures positionally arranged to define the field of view for the photoelectric light sensor in a horizontal plane and in a vertical plane, the horizontal plane being the plane containing the center points of the two lenses and the vertical plane being a plane which is perpendicular to the horizontal plane, all points in the vertical plane being equidistant from the center points of the two lenses;   An electronic circuit mechanically attached to the frame and electrically attached to the photoelectric light sensor and the lenses, the electronic circuit capable of converting the measured photocurrent to a PWM signal with a duty cycle proportional to the measured photocurrent, the electronic circuit further converting the PWM signal to the lens voltage signal;   control means for controlling transmissivity response of the lens, the control means being mechanically attached to the frame and electrically attached to the electronic circuit;   a set of batteries for powering the electronic circuit and the lenses, the set of batteries being held in a battery compartment made into the frame;   an on/off switch connecting the set of batteries to the electronic circuit, the on/off switch being integrated into the frame;   the lenses each comprising a first glass substrate, a second glass substrate, and a liquid crystal material sealed therebetween; wherein the first glass substrate comprises a first surface coated with an input polarizing film, a second surface coated with a first metal layer of Indium Tin Oxide, and a first alignment layer coated over the first metal layer; wherein the second glass substrate comprises a third surface coated with an output polarizing film, a fourth surface coated with a second metal layer of Indium Tin Oxide, and a second alignment layer coated over the second metal layer; wherein the first glass substrate and the second glass substrate are oriented so that the first alignment layer faces the second alignment layer; and wherein the lens signal voltage is connected between the first metal layer and the second metal layer.