HEAD MOUNTED DISPLAY AND METHOD FOR CONTROLLING HEAD MOUNTED DISPLAY

• US 20150049003A1
• Filed: 08/05/2014
• Published: 02/19/2015
• Est. Priority Date: 08/19/2013
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: FUJIMAKI, Yutaka, UCHIYAMA, Toshikazu
• Granted Patent: US 9,740,009 B2
• Time in Patent Office: Days
• US Class Current: 345/8
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• 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 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features

Abstract

A head mounted display includes an image display unit having an image light generation unit that generates image light based on image data and outputs the image light, the image display unit not only allowing a user who wears the image display unit around user'"'"'s head to recognize the image light in the form of a virtual image but also transmitting a surrounding scene, and a control unit that compares an index set based not only on luminance of initial image light generated based on initial image data that is original image data but also on illuminance of the transmitted surrounding scene with a first threshold set in advance and causes the image light generation unit to generate display image light that differs from the initial image light in that at least part of the luminance thereof is changed based on a result of the comparison.

Claims

1. A head mounted display comprising:

an image display unit having an image light generation unit that generates image light based on image data and outputs the image light, the image display unit not only allowing a user who wears the image display unit around user'"'"'s head to recognize the image light in the form of a virtual image but also transmitting a surrounding scene; and

a control unit that compares an index set based not only on luminance of initial image light generated based on initial image data that is original image data but also on illuminance of the transmitted surrounding scene with a first threshold set in advance and causes the image light generation unit to generate display image light that differs from the initial image light in that at least part of the luminance thereof is changed based on a result of the comparison.

2. The head mounted display according to claim 1, further comprising

an illuminance detecting section that detects the illuminance of the surrounding scene,

wherein the index is set based on the luminance of the initial image light and the detected illuminance of the surrounding scene.

3. The head mounted display according to claim 1,

wherein the index increases as the luminance of the initial image light increases but decreases as the illuminance of the transmitted surrounding scene increases, and

when the comparison result shows that the index is greater than or equal to the first threshold, the control unit causes the image light generation unit to generate the display image light that differs from the initial image light in that at least part of the luminance thereof is reduced.

4. The head mounted display according to claim 3,

wherein the index changes by a greater amount in accordance with a change in luminance in a position close to the center of a region of the image light generation unit where the image light is outputted than in accordance with a change in luminance in a position far away from the center of the region, and

the display image light is the image light that differs from the initial image light in that the amount of decrease in luminance in the position close to the center of the region is greater than the amount of decrease in luminance in the position far away from the center of the region.

5. The head mounted display according to claim 3, further comprising

a viewing range identifying section that identifies user'"'"'s viewing range,

wherein the index changes by a greater amount in accordance with a change in luminance in a position close to the center of the identified user'"'"'s viewing range than in accordance with a change in luminance in a position far away from the center of the viewing range, and

the display image light is the image light that differs from the initial image light in that the amount of decrease in luminance in the position close to the center of the viewing range is greater than the amount of decrease in luminance in the position far away from the center of the viewing range.

6. The head mounted display according to claim 1,

wherein the index increases as the luminance of the initial image light increases but decreases as the luminance of the surrounding scene increases, and

when the comparison result shows that the index is smaller than the first threshold, the control unit causes the image light generation unit to generate the display image light that differs from the image light in that at least part of the luminance thereof is increased to the extent that the index does not become greater than or equal to the first threshold.

7. The head mounted display according to claim 1, further comprising

a surrounding scene illuminance adjusting section that adjusts the illuminance of the transmitted surrounding scene with respect to the illuminance of the surrounding scene and transmits the image light,

wherein the index increases as the luminance of the initial image light increases but decreases as the illuminance of the surrounding scene increases, and

when the comparison result shows that the index is smaller than the first threshold, the control unit adjusts the surrounding scene illuminance adjusting section in such a way that at least part of the illuminance of the transmitted surrounding scene decreases to the extent that the index does not become greater than or equal to the first threshold.

8. The head mounted display according to claim 1, further comprising

a surrounding scene illuminance adjusting section that adjusts the illuminance of the transmitted surrounding scene with respect to the illuminance of the surrounding scene and transmits the image light,

the index increases as the luminance of the initial image light increases but decreases as the illuminance of the surrounding scene increases, and

when the comparison result shows that the index is smaller than the first threshold, the control unit causes the image light to contain information on adjustment of the illuminance of the transmitted surrounding scene made by the surrounding scene illuminance adjusting section as the image light to be recognized by the user.

9. The head mounted display according to claim 1,

wherein the index increases as the luminance of the initial image light increases but decreases as the illuminance of the surrounding scene increases, and

when the comparison result shows that the index is greater than or equal to the first threshold, the control unit causes the image light to contain information on control of the image light as the image light to be recognized by the user.

10. The head mounted display according to claim 1,

wherein the control unit causes the image light generation unit to generate the display image light based not only on a generation period for which the image light generation unit generates the image light but also on the index over the generation period.

11. The head mounted display according to claim 10,

wherein the index increases as the luminance of the initial image light increases but decreases as the illuminance of the surrounding scene increases, and

when an accumulation of the index for the generation period is greater than or equal to a second threshold set in advance, the control unit causes the image light to contain information on control of the image light as the image light to be recognized by the user.

12. A method for controlling a transmissive head mounted display including an image display unit having an image light generation unit that generates image light based on image data and outputs the image light, the image display unit not only allowing a user who wears the image display unit around user'"'"'s head to recognize the image light in the form of a virtual image but also transmitting a surrounding scene, the method comprising

comparing an index set based not only on luminance of initial image light generated based on initial image data that is original image data but also on illuminance of the surrounding scene with a first threshold set in advance and causing the image light generation unit to generate display image light that differs from the initial image light in that at least part of the luminance thereof is changed based on a result of the comparison.