Multi-focal display system and method

• US 10,386,636 B2
• Filed: 01/30/2015
• Issued: 08/20/2019
• Est. Priority Date: 01/31/2014
• Status: Active Grant

• Current Assignee: Magic Leap, Inc.
• Original Assignee: Magic Leap, Inc.
• Inventors: Welch, William Hudson
• Primary Examiner(s): Abaza, Ayman A
• Application Number:
  US14/611,154
• Publication Number:
  US 20150222883A1
• Time in Patent Office: 1,663 Days
• Field of Search: 348 46
• CPC Class Codes: G02B 15/00 Optical objectives with means for varying the magnification anamorphotic objectives G02B13/08
• CPC Class Codes: G02B 2027/0127 comprising devices increasing the depth of field
• CPC Class Codes: G02B 2027/0185 Displaying image at variable distance
• CPC Class Codes: G02B 27/0093 with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 30/52 the 3D volume being constructed from a stack or sequence of 2D planes, e.g. depth sampling systems
• CPC Class Codes: H04N 13/383 for tracking with gaze detection, i.e. detecting the lines of sight of the viewer's eyes

Abstract

Configurations are disclosed for presenting virtual reality and augmented reality experiences to users. The system may comprise an accommodation tracking module to track an accommodation of a user'"'"'s eyes, a first variable focus element (VFE) to switch between at least two focal planes, wherein a distance between the two focal planes is relatively consistent, and a second VFE to shift the at least two focal planes based at least in part on the tracked accommodation of the user'"'"'s eyes.

Claims

1. An augmented reality display system, comprising:

a light projection device operatively coupled to an image source for projecting a pair of consecutive image frames comprising first and second consecutive image frames for viewing by a user'"'"'s eyes through a display; and

a composite variable focus element (VFE) system comprising;

a first VFE and a second VFE arranged in series relative to the first VFE, wherein

the composite VFE is structured such that

a total optical power of the composite VFE is a combination of a first optical power of the first VFE and a second optical power of the second VFE

the first VFE is configured to switch between two focus states to focus respective first and second consecutive image frames at respective first and second depth planes, the first VFE being configured to focus respective pairs of consecutive image frames to respective pairs of depth planes,

a first distance between the first depth plane and the second depth plane is based at least in part upon a constant optical power difference comprising a difference between the first optical power of the first VFE and the second optical power of the second VFE, and

the second VFE is configured to further focus the first and second consecutive image frames to third and fourth depth planes, wherein a distance between the third depth plane and the fourth depth plane is based at least in part upon the constant optical power difference.

2. The augmented reality display system of claim 1, further comprising an accommodation tracking module configured to track an accommodation of the user'"'"'s eyes, wherein the second VFE is configured to focus the first and second consecutive image frames based at least in part on the tracked accommodation of the user'"'"'s eyes.

3. The augmented reality display system of claim 1, wherein the light projection device is a high refresh rate display, such that the user perceives the first and second consecutive image frames simultaneously.

4. The augmented reality display system of claim 1, wherein the light projection device is a Digital Light Processing (DLP) display.

5. The augmented reality display system of claim 1, wherein the first and second consecutive image frames comprise slices of a three-dimensional scene.

15. The augmented reality display system of claim 1, wherein the first VFE is configured to operate in phase with the light projection device such that the first VFE focuses each light frame of generated by the light projection device.

16. The augmented reality display system of claim 15, wherein the first VFE and the light projection device are each configured to operate at 240 Hz.

17. The augmented reality display system of claim 1, wherein the constant optical power difference is 0.3 diopters.

18. The augmented reality display system of claim 1, wherein each of the first and second consecutive image frames includes a blurred virtual object.

19. The augmented reality display system of claim 1, wherein the first VFE is operable at a first speed, and

the second VFE is operable at a second speed

greater than the first speed.

6. An augmented reality display system, comprising:

an accommodation tracking module configured to track an accommodation of a user'"'"'s eyes through a display;

a first variable focus element (VFE) configured to focus respective pairs of consecutive image frames to respective focal planes and switch between focus states to focus a pair of consecutive image frames comprising first and second consecutive image frames to respective first and second focal planes; and

a second VFE arranged in series relative to the first VFE such that a total optical power of the first FVE and the second VFE is a combination of a first optical power of the first VFE and a second optical power of the second VFE, the second VFE being configured to further focus respective first and second consecutive image frames to respective third and fourth focal planes based at least in part on the tracked accommodation of the user'"'"'s eyes,

wherein a first distance between the first focal plane and the second focal plane and a second distance between the third focal plane and the fourth focal plane are based at least in part upon a constant optical power difference comprising a difference between a first optical power of the first VFE and a second optical power of the second VFE.

7. The augmented reality display system of claim 6, further comprising an image source configured to provide image data corresponding to the first and second consecutive image frames.

8. The augmented reality display system of claim 7, further comprising a light projection display configured to transmit light associated with the first and second consecutive image frames.

9. The augmented reality display system of claim 7, wherein the first and second consecutive image comprise slices of a three-dimensional scene.

10. A method of displaying augmented reality, comprising:

providing image data corresponding to a pair of image frames comprising first and second consecutive image frames to be presented to a user through a display;

transmitting light associated with the image data to project the first and second consecutive image frames;

focusing the first image frame to a first focal plane using a first variable focus element (VFE);

focusing the second image frame to a second focal plane using the first VFE and arranged in series relative to the first VFE, wherein a total optical power of the first VFE in series with the second VFE comprises a combination of a first optical power of the first VFE and a second optical power of the second VFE, and a first distance between the first focal plane and the second focal plane is based at least in part upon a constant optical power difference comprising a difference between the first optical power of the first VFE and the second optical power of the second VFE;

focusing the first image frame to a third focal plane using the second VFE;

focusing the second image frame to a fourth focal plane using the second VFE,

wherein a distance between the third focal plane and the fourth focal plane is based at least in part upon the constant optical power difference.

11. The method of claim 10, wherein the consecutive first and second image frames comprise slices of a three-dimensional scene.

12. The method of claim 10, further comprising:

tracking an accommodation of the user'"'"'s eyes; and

the second VFE focusing respective first and second consecutive image frames to respective third and fourth focal planes based at least in part on the tracked accommodation of the user'"'"'s eyes.

13. The method of claim 10, wherein the first VFE operates at a first speed, and

the second VFE operates at a second speed

greater than the first speed.

14. The method of claim 10, further comprising presenting the consecutive first and second consecutive image frames in rapid succession such that the user perceives the first and second consecutive image frames simultaneously.

20. The method of claim 10, further comprising transmitting the light in phase with focusing the first and second consecutive image frames.

21. The method of claim 20, further comprising transmitting the light at 240 Hz, and focusing the first and second image frames at 240 Hz.

22. The method of claim 10, wherein the constant optical power difference is 0.3 diopters.

23. The method of claim 10, wherein the first and second consecutive image frames each include a blurred virtual object.