METHODS AND SYSTEMS FOR MURA DETECTION AND DEMURA

1 . A method for detecting a mura of a virtual image in a near-eye display, comprising:

acquiring the virtual image rendered in the near-eye display;

extracting a mura feature of the virtual image according to a mura type; and

evaluating a mura degree of the virtual image based on the mura type.

2 . The method according to claim 1 , wherein the mura type comprises a corner mura, a cloud mura, or a global mura.

3 . The method according to claim 2 , wherein extracting the mura feature of the virtual image according to the mura type, comprises:

extracting, when the mura type is the corner mura, the mura feature based on a luminance threshold profile.

4 . The method according to claim 2 , wherein extracting the mura feature of the virtual image according to the mura type, comprises:

extracting, when the mura type is the cloud mura, the mura feature based on a spatial gradient profile or frequency domain.

5 . The method according to claim 2 , wherein extracting the mura feature of the virtual image according to the mura type, comprises:

extracting, when the mura type is the global mura, the mura feature based on a global profile.

6 . The method according to claim 2 , wherein before extracting the mura feature of the virtual image according to the mura type, the method further comprises:

translating the virtual image into a pseudo-color image, wherein the pseudo-color image presents an absolute luminance distribution or a relative luminance distribution.

7 . The method according to claim 2 , wherein before extracting mura features of the virtual image based on the mura type, the method further comprises:

plotting the virtual image as a 3D surface to obtain a 3D image.

8 . The method according to claim 2 , wherein evaluating the mura degree of the virtual image based on the mura type, further comprising:

determining one or more primary mura types of the virtual image; and

evaluating the mura degree of the virtual image based on one or more preset thresholds corresponding to the one or more primary mura types.

9 . The method according to claim 8 , wherein the corner mura is determined as the primary mura type.

10 . The method according to claim 9 , wherein the one or more preset thresholds comprises:

a luminance scale threshold corresponding to the corner mura, or an area size threshold corresponding to the cloud mura.

11 . The method according to claim 10 , wherein the preset threshold of the luminance scale threshold is 30%, and the preset threshold of the area size threshold is 30%.

12 . The method according to claim 1 , wherein acquiring the virtual image rendered in the near-eye display, further comprises:

acquiring the virtual image under a solid test pattern or multiple partial test patterns, wherein the partial test patterns are with various gray values and colors.

13 . The method according to claim 12 , wherein the test pattern is a full white test pattern.

14 . The method according to claim 12 , wherein the test pattern is a full gray test pattern.

15 . The method according to claim 12 , wherein the virtual image is rendered under an ambient light condition.

16 . The method according to claim 1 , wherein before extracting the mura feature of the virtual image according to the mura type, the method further comprises:

preprocessing the virtual image by eliminating one or more of a noise or a distortion.

17 . A system for detecting a mura in a virtual image rendered in a near-eye display, comprising:

an image generator configured to render a virtual image;

an imager configured to acquire the virtual image;

a positioner coupled with the image generator and the imager, and configured to control a relative position of the near-eye display and the imager; and

a processor coupled with the imager and configured to evaluate a mura degree of the virtual image.

18 . The system according to claim 17 , wherein the processor is further configured to:

extract a mura feature of the virtual image according to a mura type; and

evaluate the mura degree of the virtual image based on the mura type.

19 . The system according to claim 18 , wherein the mura type comprises a corner mura, a cloud mura, or a global mura.

20 . The system according to claim 17 , wherein the imager comprises:

a near-eye display lens configured to emulate a human eye for acquiring the virtual image; and

a light measuring device configured to measure the virtual image.