Automated detection of eye alignment

Patent metadata

Field	Value
Publication number	US-2016270653-A1
Application number	US-201414893626-A
Country	US
Kind code	A1
Filing date	Nov 7, 2014
Priority date	Nov 7, 2013
Publication date	Sep 22, 2016
Grant date	—

Abstract

An example method for automatically measuring a subject's phoria while the subject fixates on a visual target can include capturing an image of at least one of the subject's eyes using an image capturing device. The image can include a reflection of light from at least one of the subject's eyes. The method can also include analyzing the image to identify a position of the reflection of the light within at least one of the subject's eyes, and determining a phoria measurement based on the position of the reflection of the light within at least one of the subject's eyes.

First claim

1 . A method for automatically measuring a subject's phoria while the subject fixates on a visual target, comprising:
capturing an image of at least one of the subject's eyes using an image capturing device, the image including a reflection of light from any surface of the at least one of the subject's eyes; analyzing the image to identify a position of the reflection of the light within the at least one of the subject's eyes; determining a phoria measurement based on the position of the reflection of the light within the at least one of the subject's eyes; performing an autorefraction measurement, the autorefraction measurement measuring a power of one of the subject's eyes while focusing on the visual target; and calculating an accommodative convergence accommodation ratio based on a position of the reflection of the light within at least one of the subject's eyes and the autorefraction measurement.

2 . The method of claim 1 , further comprising comparing a position of the reflection of the light within one of the subject's eyes and a position of the reflection of the light within another one of the subject's eyes, wherein the phoria measurement is determined based on a result of the comparison.

3 . The method of claim 1 , wherein analyzing the image to identify a position of the reflection of the light within the at least one of the subject's eyes further comprises identifying a position of the reflection of the light relative to a landmark of the at least one of the subject's eyes.

4 . The method of claim 1 , wherein the image includes a reflection of the light from at least one of an outer or inner surface of a cornea or an outer or inner surface of a lens of the at least one of the subject's eyes.

5 . The method of claim 4 , wherein the image is a first, second, third or fourth Purkinje image.

6 . The method of claim 1 , further comprising covering and uncovering the at least one of the subject's eyes, wherein the image is captured after uncovering the at least one of the subject's eyes.

7 . The method of claim 6 , further comprising capturing a sequence of images of the subject's eyes after uncovering the at least one of the subject's eyes, and comparing a position of the reflection of the light within the at least one of the subject's eyes in one of the sequence of images to a position of the reflection of the light within the at least one of the subject's eyes in another of the sequence of images to determine any a magnitude and a direction of any movement after the at least one of the subject's eyes is uncovered.

8 . The method of claim 1 , further comprising covering at least one of the subject's eyes with a filter, wherein the image is captured while at least one of the subject's eyes is covered by the filter.

9 . (canceled)

10 . The method of claim 1 , wherein the image is captured in response to the power of the one of the subject's eyes being within a predetermined range.

11 . The method of claim 1 , further comprising adjusting the phoria measurement based on the autorefraction measurement.

12 . (canceled)

13 . (canceled)

14 . (canceled)

15 . The method of claim 1 , further comprising illuminating at least one of the subject's eyes with a light using a light source to create the reflection, wherein the light is in a visible or non-visible portion of an electromagnetic spectrum.

16 . (canceled)

17 . An apparatus for automatically measuring a subject's phoria while the subject fixates on a visual target, comprising:
an image capturing device for capturing an image of at least one of the subject's eyes; a processor; and a memory in operable communication with the processor, the memory having computer-executable instructions stored thereon that, when executed by the processor, cause the processor to:
receive the image from the image capturing device, the image including a reflection of light from any surface of the at least one of the subject's eyes;
analyze the image to identify a position of the reflection of the light within the at least one of the subject's eyes;
determine a phoria measurement based on the position of the reflection of the light within the at least one of the subject's eyes;
perform an autorefraction measurement that measures a power of the one of the subject's eyes while focusing on the visual target; and
calculate an accommodative convergence accommodation ratio based on a position of the reflection of the light within at least one of the subject's eyes and the autorefraction measurement.

18 . The apparatus of claim 17 , wherein the memory has further computer-executable instructions stored thereon that, when executed by the processor, cause the processor to compare a position of the reflection of the light within one of the subject's eyes and a position of the reflection of the light within another one the subject's eyes, wherein the phoria measurement is determined based on a result of the comparison.

19 . The apparatus of claim 17 , wherein analyzing the image to identify a position of the reflection of the light within at least one of the subject's eyes further comprises identifying a position of the reflection of the light relative to a landmark of the at least one of the subject's eyes.

20 . The apparatus of claim 17 , wherein the image includes a reflection of the light from at least one of an outer or inner surface of a cornea or an outer or inner surface of a lens of at least one of the subject's eyes.

21 . The apparatus of claim 20 , wherein the image is a first, second, third or fourth Purkinje image.

22 . The apparatus of claim 17 , wherein the image is captured after covering and uncovering the at least one of the subject's eyes.

23 . The apparatus of claim 22 , wherein the image capturing device is a video capturing device or a camera for capturing a sequence of images of the subject's eyes after uncovering the at least one of the subject's eyes and wherein the processor executes computer readable instructions to compare a position of the reflection of the light within the at least one of the subject's eyes in one of the sequence of images to a position of the reflection of the light within the at least one of the subject's eyes in another of the sequence of images to determine a magnitude and a direction any movement after the at least one of the subject's eyes is uncovered.

24 . The apparatus of claim 17 , wherein the image is captured while at least one of the subject's eyes is covered by a filter.

25 . The apparatus of claim 23 , further comprising a display device, wherein the apparatus defines a first surface and a second surface opposite to the first surface, the display device being arranged on the first surface and the image capturing device being arranged on the second surface.

26 . The apparatus of claim 17 , further comprising a light source for illuminating the at least one of the subject's eyes with a light.

27 . (canceled)

28 . The apparatus of claim 17 , wherein the apparatus provides the visual target for the subject.

29 . The apparatus of claim 17 , wherein the image is captured in response to the power of the one of the subject's eyes being within a predetermined range.

30 . The apparatus of claim 17 , wherein the memory has further computer-executable instructions stored thereon that, when executed by the

Assignees

• Ohio State Innovation Foundation

Inventors

• Bailey Melissa Diane

Classifications

• A61B3/085 Primary

  for testing strabismus · CPC title

• A61B3/103

  for determining refraction, e.g. refractometers, skiascopes · CPC title

• A61B3/113 Primary

  for determining or recording eye movement · CPC title

• A61B3/14

  Arrangements specially adapted for eye photography · CPC title

• A61B3/0091

  Fixation targets for viewing direction · CPC title