PROVISIONAL PATENT FOR MEASURING VISUAL CYLINDER USING A TWO-DIMENSIONAL SURFACE ABSTRACT OF THE DISCLOSURE:

Transcription

1 PROVISIONAL PATENT FOR MEASURING VISUAL CYLINDER USING A TWO-DIMENSIONAL SURFACE Inventors: Reid Laurens, Allan Hytowitz, Alpharetta, GA (US) 5 ABSTRACT OF THE DISCLOSURE: Visual images on a display surface such as a square and circle appear to be oblong and ovoid when the natural cylinder of the eye is other than symmetrical. The adjustment difference in the appearance of an oblong and ovoid image on that display surface so that it appears to be perfectly symmetrical can be used as an indication of the difference in cylindrical symmetry of 10 the eye. REFERENCES CITED: OPTOELECTRONIC SYSTEM USING SPATIOCHROMATIC TRIANGULATON, Joseph Cohen-Sabban, US 6,573,998, June 3, CROSS-REFERENCE TO RELATED APPLICATIONS The present non-provisional patent application claims the benefit of priority of U.S. Patent No. 8,083,353.which is entitled Animated Image Vision Test granted December 27, 2011, and 20 Claims of Application No. 13/337,277 which is incorporated in full by reference herein. The present invention relates generally to vision testing devices, methods, and more particularly to a novel method for more accurately testing vision and acuity related to the correctness of prescriptions for eyeglasses and contact lenses.

2 25 STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not Applicable REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM 30 LISTING COMPACT DISK APPENDIX Not Applicable BACKGROUND OF THE INVENTION Adjustments to visual attributes such as sphere (magnification power) and astigmatism (planar 35 lack of lens uniformity) can be determined by looking at images on a two-dimensional surface. Because of the biological nature of visual systems, symmetrical shapes such as a square and circle frequently appear to be ovoid and oblong due to the apparent lack of cylindrical symmetry of the lens of the eye. Determination of cylinder adjustment is part of the refraction process and typically involves a 40 cylinder adjustment lens. It is regarded as not possible to determine cylinder adjustment when viewing a 2-dimentional image without the cylinder adjustment lens. A shape such as a square or circle that is already ovoid and oblong but appears to a symmetrical square and circle can be used to calibrate the cylinder adjustment. The difference between the actual ovoid and oblong shape and the apparent perfect symmetry can be used to measure the 45 difference in cylinder. The differential ovoid and oblong shapes can be printed, electronically generated, or can be created optically with a virtual image. The test images can be a simple square or circle; or can be more complex images as described below, to increase precision in the testing process.

3 50 DETAILED DESCRIPTION OF THE INVENTION: A Dyop (short for dynamic optotype) image has a higher degree of acuity perception due to the strobic effect of the segment/gap contrast and the visual preference for detecting motion. That perception increases the ability to discern the symmetry of the Dyop image as well as its use for determining acuity based upon the rotation detection threshold distance. Deviations from 55 the Dyop image being non-symmetrical (ovoid) are more perceptible than viewing static circular images. A series of ovoid Dyop images are presented to the observer using unaided vision. (See figure 2.) The observer is asked to determine which of them is actually symmetrical. The images are scaled such that their overall diameter is no more than one-third of the total viewing area, to 60 prevent the subject from using the borders of the device used to create the image as reference points for the shape of the test image. Visual distortion from less than symmetrical visual cylinder will result in the central image to appear ovoid similar to the peripheral Dyop images. Software will allow the observer to adjust the central image so that it appears symmetrical. The software calibration from the actual symmetrical circular image to the apparent symmetrical 65 circular image will allow the calibration of the necessary cylinder adjustment in the refraction. A similar correction when viewing images that have less than symmetrical axis will allow the corrective adjustment for measuring deviations of visual axis. The rotational orientation of deviation of the test image can be changed to determine the exact rotational orientation of deviation in the viewer s eye, so the correction can be applied in the proper rotational 70 orientation. A parallelogram (see figure 1) or other geometric shape may also be used for the symmetrical adjustment when that center image appears asymmetrical with the correction of that image to a symmetrical appearance is an indicator of the necessary adjustment of cylinder and axis.

4 75 BRIEF DESCRIPITION OF THE SEVERAL VIEWS OF THE DIAGRAMS: FIG 1: Modified parallelogram shapes used for cylinder adjustment Item 1 - Parallelogram top right Item 2 - Rectangle short Item 3 - Parallelogram top left 80 Item 4 - Rectangle narrow Item 5 Square Item 6 - Rectangle wide Item 7 - Parallelogram top left Item 8 - Rectangle wide 85 Item 9 - Parallelogram top right FIG 2: Modified semi-spherical dynamic optotype shapes used for cylinder adjustment Item 1 - Dyop top right Item 2 - Dyop short Item 3 - Dyop top left 90 Item 4 - Dyop narrow Item 5 Circle Item 6 - Dyop wide Item 7 - Dyop top left Item 8 - Dyop wide 95 Item 9 - Dyop top right

5 100 CLAIMS: 1. I claim a method of determining visual cylinder on a 2 dimensional surface using the adjustment of an asymmetrical ovoid dynamic optotype or a simple asymmetrical shape such that its adjusted appearance is a symmetrical circle or symmetrical shape. The calculated difference between the actual asymmetrical image and its apparent 105 symmetrical appearance is a measure of visual cylinder

6 125 DRAWINGS: FIG 1 130

7 135 FIG 2 140