Central vision impairment compensation

• US 9,180,053 B2
• Filed: 01/29/2013
• Issued: 11/10/2015
• Est. Priority Date: 01/29/2013
• Status: Active Grant

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Dalal, Edul N., Wu, Wencheng
• Primary Examiner(s): Lee, Michael
• Application Number:
  US13/752,631
• Publication Number:
  US 20140210970A1
• Time in Patent Office: 1,015 Days
• Field of Search: 348/62, 348/63, 348/580
• US Class Current: 1/1
• CPC Class Codes: A61F 9/08 Devices or methods enabling eye-patients to replace direct visual perception by another kind of perception
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 2027/0138 comprising image capture systems, e.g. camera
• CPC Class Codes: G02B 2027/014 comprising information/image processing systems
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

A method, system, and processor-readable medium for non-invasive visual compensation for a person suffering from central vision impairment. Digital images of a target field of view can he obtained and processed to generate processed images thereof, wherein central regions of the digital images that normally would reach an impaired portion of a retina of the person are moved to other regions of the target field of view. The processed images can be presented to the person such that the central regions are now directed at an unimpaired peripheral portion of the retina of the person.

Claims

1. A method for non-invasive visual compensation for a person suffering from central vision impairment, said method comprising:

obtaining digital images of a target field of view for conversion of said digital images from rectangular coordinates (x₀,y₀) to polar coordinates (r₀,θ

₀);

processing said digital images to generate processed images thereof including polar coordinates (r<sub>1, θ

1</sub>) converted back to rectangular coordinates (x₁,y₁) wherein central regions of said digital images that normally would reach an impaired portion of a retina of said person are moved to other regions of said target field of view; and

presenting said processed images to said person such that said central regions are now directed at an unimpaired peripheral portion of said retina of said person, thereby expanding outward a central vision region corresponding to a damaged retinal area of said retina of said person so that said central vision region is now in a peripheral vision area.

2. The method of claim 1, wherein processing said digital images further includes leaving an angular position unchanged and expanding a radius according to θ

₁=θ

₂ and r₁=R+m·

r₀ wherein R represents an image radius corresponding to a damaged retinal central area of said retina of said person and m represents a magnification factor and wherein said digital images are obtained via at least one video camera and said processed images are presented via at least one video display.

3. The method of claim 2, wherein said at least one video camera and said at least one video display are mounted in a configuration to follow a direction of view of said person.

4. The method of claim 3, wherein said at least one video display is positioned so as to enable the output to reach a substantial portion of said unimpaired peripheral portion of said retina.

5. The method of claim 2, wherein said processing of said images comprises warping said images based on a pre-determined spatial transformation.

6. The method of claim 5, wherein said pre-determined spatial transformation comprises distorting said digital images such that said central region is moved radially outward and the distortion function is parameterized by a size and a location of said center of said central region to be moved and a magnification desired for moving said digital images of said central region to other regions.

7. The method of claim 5, wherein said pre-determined spatial transformation comprises a look-up table.

8. The method of claim 5, wherein said pre-determined spatial transformation is determined based on results of a set of procedures including:

conducting a specially designed vision test; and

conducting an instrumented physical or psychophysical measurement of the eyes of said person.

9. A system for non-invasive visual compensation for a person suffering from central vision impairment, said system comprising:

at least one video camera;

at least one video display;

a processor that communicates with said at least one video camera and said at least one video display;

a data bus coupled to said processor; and

a computer-usable medium embodying computer program code, said computer-usable medium being coupled to said data bus, said computer program code comprising instructions executable by said processor and configured for;

obtaining digital images of a target field of view utilizing said at least one video camera for conversion of said digital images from rectangular coordinates (x₀,y₀) to polar coordinates (r₀,θ

₀);

processing said digital images to generate processed images thereof including polar coordinates (r₁,θ

₁) converted back to rectangular coordinates (x₁,y₁) wherein central regions of said digital images that normally would reach an impaired portion of a retina of said person are moved to other regions of said target field of view; and

presenting said processed images to said person utilizing said at least one video display such that said central regions are now directed at an unimpaired peripheral portion of said retina of said person, thereby expanding outward a central vision region corresponding to a damaged retinal area of said retina of said person so that said central vision region is now in a peripheral vision area.

10. The system of claim 9, wherein processing said digital images further includes leaving an angular position unchanged and expanding a radius according to θ

₁=θ

₂ and r₁=R+m·

r₀ wherein R represents an image radius corresponding to a damaged retinal central area of said retina of said person and m represents a magnification factor and wherein said at least one video camera and said at least one video display are mounted in a configuration to follow a direction of view of said person.

11. The system of claim 10, wherein said at least one video display is positioned so as to enable the output to reach a substantial portion of said unimpaired peripheral portion of said retina.

12. The system of claim 10, wherein said processing said digital images further comprises warping said images based on a pre-determined spatial transformation.

13. The system of claim 12, wherein said pre-determined spatial transformation comprises distorting said digital images such that said central region is moved radially outward and the distortion function is parameterized by a size and a location of said center of said central region to be moved and a magnification desired for moving said digital images of said central region to other regions.

14. The system of claim 13, wherein said pre-determined spatial transformation comprises a look-up table.

15. The system of claim 13, wherein said pre-determined spatial transformation is determined based on results of a set of procedures including at least one of:

conducting a specially designed vision test; and

conducting an instrumented physical or psychophysical measurement of the eyes of said person.

16. The system of claim 13, wherein said pre-determined spatial transformation is customized to:

a specific person;

a specific task; and

a specific period of time.

17. The system of claim 10, wherein said at least one video display comprises at least one of:

a virtual reality device;

an augmented reality device;

a head-mounted display;

a laser scanning retinal display, and

a digital projector display.

18. The system of claim 10, wherein said central vision impairment comprises macular degeneration.

19. A processor-readable medium storing code representing instructions to cause a process for non-invasive visual compensation for a person suffering from central vision impairment, said code comprising code to:

obtain digital images of a target field of view for conversion of said digital images from rectangular coordinates ( x₀,y₀) to polar coordinates (r₀,θ

₀);

process said digital images to generate processed images thereof including polar coordinates (r₁, θ

₁) converted back to rectangular coordinates (x₁, y₁), wherein central regions of said digital images that normally would reach an impaired portion of a retina of said person are moved to other regions of said target field of view; and

present said processed images to said person such that said central regions are now directed at an unimpaired peripheral portion of said retina of said person, thereby expanding outward a central vision region corresponding to a damaged retinal area of said retina of said person so that said central vision region is now in a peripheral vision area.

20. The processor-readable medium of claim 19, wherein processing said digital images further includes leaving an angular position unchanged and expanding a radius according to θ

₁=θ

₂ and r₁=R+m·

r₀ wherein R represents an image radius corresponding to a damaged retinal central area of said retina of said person and m represents a magnification factor and wherein said digital images are obtained via at least one video camera and said processed images are presented via at least one video display.