Head-mounted display apparatus and optical system

Patent metadata

Field	Value
Publication number	US-10466479-B2
Application number	US-201615287760-A
Country	US
Kind code	B2
Filing date	Oct 7, 2016
Priority date	Oct 7, 2016
Publication date	Nov 5, 2019
Grant date	Nov 5, 2019

Abstract

An optical system including a first optical waveguide device, and a second optical waveguide device is provided. The first optical waveguide device includes a first light entering surface, a first light exiting surface and a first beam splitter. An image light emitted from the display enters the first optical waveguide device through the first light entering surface. The second optical waveguide device includes a second light entering surface, a second light exiting surface and a second beam splitter. The second light entering surface faces the first light exiting surface. A gap is formed between the second light entering surface and the first light exiting surface. Besides, a head-mounted display using the optical system described above is also provided.

First claim

What is claimed is:

1. A head-mounted display apparatus, comprising:
a display, configured to emit an image light;
a first optical waveguide device, comprising:
a first light entering surface, wherein the image light enters the first optical waveguide device through the first light entering surface;
a first light exiting surface, wherein the first light exiting surface is directly connected to the first light entering surface so as to form an angle that is less than 90 degrees and greater than 0 degree; and
a first beam splitter, disposed in the first optical waveguide device; and

a second optical waveguide device, disposed beside the first optical waveguide device, the second optical waveguide device comprising:
a second light entering surface, facing the first light exiting surface;
a second light exiting surface, wherein the second light exiting surface is directly connected to the second light entering surface so as to form an angle that is less than 90 degrees and greater than 0 degree; and
a second beam splitter, disposed in the second optical waveguide device, wherein the second light entering surface and the first light exiting surface have a gap therebetween.

2. The head-mounted display apparatus as claimed in claim 1 , wherein the image light entered the first optical waveguide device is adapted to reflect on the first beam splitter to leave the first optical waveguide device through the first light exiting surface, and the image light which left the first optical waveguide device is adapted to enter the second optical waveguide device through the second light entering surface, wherein the image light is adapted to reflect on the second beam splitter to leave the second optical waveguide device through the second light exiting surface.

3. The head-mounted display apparatus as claimed in claim 2 , wherein the image light is adapted to be totally reflected to transmit in the first optical waveguide device and the second optical waveguide device.

4. The head-mounted display apparatus as claimed in claim 1 , wherein the image light left the second optical waveguide device is adapted to enter a pupil, wherein before entering the first optical waveguide device, the image light has a first entrance pupil opening angle on a first direction and a second entrance pupil opening angle on a second direction, the image light which left the second optical waveguide device and entered the pupil has a first light convergence angle on a third direction and a second light convergence angle on a fourth direction, wherein the first direction is perpendicular to the second direction, the third direction is perpendicular to the fourth direction, the first entrance pupil opening angle is equal to the first light convergence angle, and the second entrance pupil opening angle is equal to the second light convergence angle.

5. The head-mounted display apparatus as claimed in claim 1 , wherein the first optical waveguide device further comprises a first side surface connected to the first light entering surface, and the first side surface is parallel to the first light exiting surface, the second optical waveguide device further comprises a second side surface connected to the second light entering surface, and the second side surface is parallel to the second light exiting surface, wherein the first beam splitter is disposed between the first side surface and the first light exiting surface and the second beam splitter is disposed between the second side surface and the second light exiting surface.

6. The head-mounted display apparatus as claimed in claim 5 , wherein the first beam splitter is not parallel to the first side surface and not parallel to the first light entering surface, and the second beam splitter is not parallel to the second side surface and not parallel to the second light entering surface.

7. The head-mounted display apparatus as claimed in claim 5 , wherein the image light is adapted to be totally reflected to transmit between the first side surface and the first light exiting surface, and the image light is adapted to be totally reflected to transmit between the second side surface and the second light exiting surface, wherein the second light exiting surface and the image light adapted to be totally reflected on the second light exiting surface have a first angle therebetween, the second beam splitter and the second light exiting surface have a second angle therebetween, the first angle plus the second angle is less than 90 degrees, and a sum of the first angle and two times of the second angle is 90 degrees.

8. The head-mounted display apparatus as claimed in claim 1 , wherein the first optical waveguide device comprises a first body portion and a first wedge portion adjacent to the first body portion, the first beam splitter is disposed in the first body portion, a surface of the first wedge portion away of the first body portion is the first light entering surface, and the first body portion and the first wedge portion form the first light exiting surface together.

9. The head-mounted display apparatus as claimed in claim 1 , wherein the second optical waveguide device comprises a second body portion and a second wedge portion adjacent to the second body portion, the second beam splitter is disposed in the second body portion, a surface of the second wedge portion away of the second body portion is the second light entering surface, and the second body portion and the second wedge portion form the second light exiting surface together.

10. The head-mounted display apparatus as claimed in claim 9 , wherein an index of refraction of the second wedge portion is the same as an index of refraction of the second body portion, the second light entering surface and the second light exiting surface have a third angle therebetween, the second beam splitter and the second light exiting surface have a second angle therebetween, the second angle and the third angle is less than 90 degrees, and the third angle is equal to two times of the second angle.

11. The head-mounted display apparatus as claimed in claim 1 , wherein a width of the gap is ranged in 2 micrometers to 200 micrometers.

12. The head-mounted display apparatus as claimed in claim 1 , wherein the first light exiting surface is parallel to the second light entering surface.

13. The head-mounted display apparatus as claimed in claim 1 , wherein the number of the first beam splitter is more than one, and the first beam splitters are parallel to each other and are arranged in intervals.

14. The head-mounted display apparatus as claimed in claim 1 , wherein the number of the second beam splitter is more than one, and the second beam splitters are parallel to each other and are arranged in intervals.

15. An optical system, adapted to receive an image light, the optical system comprising:
a first optical waveguide device, comprising:
a first light entering surface, wherein the image light enters the first optical waveguide device through the first light entering surface;
a first light exiting surface, wherein the first light exiting surface is directly connected to the first light entering surface so as to form an angle that is less than 90 degrees and greater than 0 degree; and
a first beam splitter, disposed in the first optical waveguide device; and

a second optical waveguide device, disposed beside the first optical waveguide device, the second optical waveguide device comprising:
a second light entering surface, facing the first light exiting surface;
a second light exiting surface, wherein the second light exiting surface is directly connected to the seco

Assignees

• Coretronic Corp

Inventors

• Shih Chih-Wei
• Lee Yi-Sheng
• Wei Chung-Ting
• Cheng Chuan-Te

Classifications

• G02B27/0172 Primary

  characterised by optical features · CPC title

• G02B6/0075

  Arrangements of multiple light guides (G02B6/0028 takes precedence) · CPC title

• G02B6/0046

  Tapered light guide, e.g. wedge-shaped light guide · CPC title

• G02B6/0028

  Light guide, e.g. taper · CPC title

• G02B27/0101

  characterised by optical features (G02B27/0172 takes precedence) · CPC title