Active visual alignment stimuli in fundus photography

Patent metadata

Field	Value
Publication number	US-11006827-B2
Application number	US-201816175719-A
Country	US
Kind code	B2
Filing date	Oct 30, 2018
Priority date	Oct 30, 2017
Publication date	May 18, 2021
Grant date	May 18, 2021

Abstract

The technology described herein is directed to a fundus camera and, more specifically, to a fundus camera having a display that projects active visual alignment stimuli onto an eye of an examinee via one or more components of an optimal assembly. The active visual alignment stimuli are dynamically adjusted to guide an examinee toward optical alignment for fundus imaging.

First claim

The invention claimed is:

1. A fundus camera comprising:
an optical assembly including one or more optical components;
a display adapted to project an animated fixation target onto an eye of an examinee via the optical assembly;
an illumination source adapted to emit one or more flashes onto the eye of the examinee via the optical assembly;
a camera adapted to capture multiple images of the examinee's fundus during the one or more flashes; and
a control system operably coupled with the display, the illumination source and the camera, and configured to direct the display to dynamically adjust the animated fixation target within a fixation zone for facilitating dilation of a pupil of the eye while guiding the examinee's line of sight toward fixation alignment.

2. The fundus camera of claim 1 , wherein to dynamically adjust the animated fixation target within the fixation zone, the control system is configured to direct the display to progressively shrink the animated fixation target until the animated fixation target becomes a fixation point.

3. The fundus camera of claim 1 , wherein to dynamically adjust the animated fixation target within the fixation zone, the control system is configured to direct the display to progressively shrink the fixation zone until the fixation zone becomes a fixation point, and wherein to progressively shrink the fixation zone, the control system is configured to maintain a relative position of the animated fixation target within the fixation zone.

4. The fundus camera of claim 1 , wherein the control system is configured to direct the display to project the animated fixation target for a preset duration, and wherein the animated fixation target comprises one or more preset animations.

5. The fundus camera of claim 1 , wherein the control system is adapted to receive a real-time video feed from the camera and direct the display to project the real-time video feed onto the eye of the examinee.

6. The fundus camera of claim 1 , further comprising:
an eye tracker adapted to monitor the eye of the examinee while the control system directs the display to dynamically adjust, based on an output of the eye tracker, the animated fixation target within the fixation zone.

7. The fundus camera of claim 6 , wherein to monitor the eye of the examinee, the eye tracker is adapted to track a location or size of the examinee's pupil, and wherein the control system directs the display to dynamically adjust, based on the location or size of the examinee's pupil, the animated fixation target within the fixation zone.

8. The fundus camera of claim 6 , wherein the eye tracker comprises an iris camera and an infrared illumination source positioned to illuminate the examinee's eye.

9. The fundus camera of claim 6 , wherein the control system is configured to determine that the fixation alignment is achieved based on the output of the eye tracker, and wherein the control system triggers, responsive to the determination that the fixation alignment is achieved, the illumination source to emit the one or more flashes and the camera to capture the multiple images of the examinee's fundus.

10. The fundus camera of claim 6 , wherein the output of the eye tracker comprises a real-time video feed, and wherein the control system is configured to direct the display to project the real-time video feed onto the eye of the examinee.

11. The fundus camera of claim 10 , further comprising a trigger mechanism adapted to receive an input from the examinee, wherein the control system is configured to direct the camera to capture the multiple images of the examinee's fundus responsive to receiving the input.

12. The fundus camera of claim 1 , wherein the control system is configured to direct the display to project one or more camera state indicators onto the eye of the examinee.

13. The fundus camera of claim 1 , wherein the display is situated within an image path at a conjugate plane of a retina.

14. A fundus camera comprising:
an optical assembly including one or more optical components;
a display adapted to project an animated fixation target onto an eye of an examinee via the optical assembly;
an eye tracker adapted to monitor the eye of the examinee; and
a control system operably coupled with the display and the eye tracker, and configured to direct the display to dynamically adjust the animated fixation target within a fixation zone based on an output of the eye tracker to dilate a pupil of the eye while guiding the examinee's line of sight toward fixation alignment.

15. The fundus camera of claim 14 , further comprising:
an illumination source adapted to emit one or more flashes; and
a camera adapted to capture multiple images of the examinee's fundus during the one or more flashes.

16. The fundus camera of claim 14 , wherein to monitor the eye of the examinee, the eye tracker is adapted to track a location or size of the examinee's pupil, and wherein the control system is configured to:
continuously monitor, via the eye tracker, a degree or measure of alignment;
dynamically adjust the animated fixation target within the fixation zone based on the degree or measure of alignment; and
determine that alignment is achieved when the degree or measure of alignment exceeds a predetermined threshold.

17. A fundus camera comprising:
an optical assembly including one or more optical components;
a display adapted to project an active alignment pattern and a reference alignment pattern onto an eye of an examinee via the optical assembly;
a camera adapted to capture one or more images of the examinee's fundus;
an eye tracker adapted to monitor a position of the eye of the examinee relative to the fundus camera; and
a control system operably coupled with the display, the camera, and the eye tracker, and configured to direct the display to guide the examinee toward pupil-to-camera alignment by dynamically adjusting the active alignment pattern relative to the reference alignment pattern based on the position of the eye of the examinee relative to the fundus camera.

18. The fundus camera of claim 17 , wherein the position the eye tracker is adapted to monitor comprises an axial displacement and a two-dimensional lateral shift of the eye of the examinee relative to the fundus camera.

19. The fundus camera of claim 18 , wherein control system is configured to:
dynamically adjust a size of the active alignment pattern to visually indicate the axial displacement of the eye of the examinee relative to the fundus camera; or
dynamically adjust a two-dimensional position of the active alignment pattern on the display to visually indicate the two-dimensional lateral shift of the eye of the examinee relative to the fundus camera; or
dynamically adjust a color of the active alignment pattern to visually indicate the axial displacement or the two-dimensional lateral shift of the eye of the examinee relative to the fundus camera.

20. The fundus camera of claim 18 , wherein the control system is configured to:
monitor the axial displacement and the two-dimensional lateral shift of the eye of the examinee relative to the fundus camera to determine when pupil-to-camera alignment is achieved,
wherein the active alignment pattern and the reference alignment pattern visually match in size and position on the display when the pupil-to-camera alignment is achieved.

Assignees

• Verily Life Sciences Llc

Inventors

• Kramer Ryan
• Kavusi Sam
• Glik Eliezer
• Lee Seung Ah
• Belthangady Chinmay

Classifications

• A61B3/0091 Primary

  Fixation targets for viewing direction · CPC title

• A61B3/152 Primary

  for aligning · CPC title

• A61B3/145

  by video means · CPC title

• A61B3/1225

  using coherent radiation · CPC title

• A61B3/113

  for determining or recording eye movement · CPC title