Subjective wavefront refraction using continuously adjustable wave plates of Zernike function
OwnerShui T. Laiinventor
Life of this patent
Estimating the term…
Abstract
A wavefront device (FIG. 1A) produces adjustable amplitudes in optical path differences and adjustable axis orientation angles, two substantially identical wave plates (225) have a wavefront profile of at least the third order Zernike polynomial function which are not circularly symmetric, as denoted by Z(i,j) where i>3 and jO. The wave plates are mounted in rotatable mounts (124) with their optical centers substantially aligned with each other.
Claims23
A method of generating a subjective optical prescription with a Zernike wave plate having an ability to substantially continuously adjust its amplitude and optic axis angle, comprising:
- (a) providing at least one point source as the viewing target,
- (b) providing two substantially identical wave plates with wavefront profile of Zernike polynomial function;
- (c) aligning optical centers of the wave plates;
- (d) rotating the wave plates in opposite direction in one or more substantially identical angular amounts until a patient indicates an optimal setting;
- (e) rotating the entire assembly including the two wave plates to an optic axis angle indicated as optimal by the patient;
- and
- (f) generating an optical prescription based on initial positions and rotation amounts of the two wave plates.
A method of determining second order and higher order aberrations of a patient's eye, comprising,
- (a) providing a priority list of Zernike functions in a predetermined order;
- (b) providing at least one point source as a viewing target;
- (c) selecting a first adjustable wave plate according to the order in the priority list;
- (d) placing the first adjustable wave plate in a patient's line of sight;
- (e) minimizing a refractive error of the patient by adjusting amplitude and angle of the first adjustable wave plate while the patient is looking at the viewing target;
- and
- (f) repeating (c) through (e) for one or more further wave plate according to the order in the priority list, until no appreciable further improvement in image quality of the point source is observed by the patient.
A device for determining or correcting aberrations of an eye comprising:
- (a) at least one adjustable wave plate, the amplitude and the optic axis angle being adjustable,
- (b) a priority list of Zernike functions based on which one or more adjustable wave plates are selected in accordance with an order of Zernike functions in the list, and
- (c) a point source as a viewing target,
- (d) wherein the one or more selected wave plates are placed at a conjugate corneal or spectacle plane of a patient's eye, and a patient searches for predetermined image end points while looking at the point source while angle and amplitude of the selected wave plate are varied.
Dependencies are inferred from the claim text.