Display device having common light path region

Patent metadata

Field	Value
Publication number	US-11940628-B2
Application number	US-202217648534-A
Country	US
Kind code	B2
Filing date	Jan 20, 2022
Priority date	Jan 20, 2022
Publication date	Mar 26, 2024
Grant date	Mar 26, 2024

Abstract

Examples are disclosed that relate to display devices having a common light path region. One example provides a display device comprising a light source configured to emit illumination light along an illumination path, and a spatial light modulator configured to modulate the illumination light and emit the modulated illumination light as image light along an imaging path, wherein at least a portion of the illumination path and at least a portion of the imaging path extend through a common light path region. The display device further comprises one or more optical elements positioned within the common light path region, at least one optical element being configured to guide the illumination light as the illumination light travels through the common light path region toward the spatial light modulator, and shape the image light as the image light travels through the common light path region.

First claim

The invention claimed is:

1. A display device, comprising:
a light source configured to emit illumination light along an illumination path, the illumination light used to achieve illumination of a spatial light modulator;
the spatial light modulator configured to receive and modulate the illumination light, and emit the modulated illumination light as image light along an imaging path, wherein at least a portion of the illumination path and at least a portion of the imaging path extend through a common light path region extending along an optical axis of the display device; and
two or more optical elements positioned within the common light path region, at least one optical element of the two or more of optical elements being configured to (1) guide the illumination light as the illumination light travels through the common light path region toward the spatial light modulator, and (2) shape the image light as the image light travels through the common light path region, the two or more optical elements including a lens within the common light path region configured to both transmit the illumination light prior to modulation by the spatial light modulator, and also transmit the image light after modulation by the spatial light modulator, and the two or more optical elements including a partially cut lens positioned within the common light path region.

2. The display device of claim 1 , wherein the two or more optical elements include two or more lenses.

3. The display device of claim 1 , wherein the two or more optical elements include a beam splitter.

4. The display device of claim 1 , wherein the spatial light modulator includes one of a liquid crystal on silicon display or a digital minor device.

5. The display device of claim 1 , further comprising one or more imaging optical elements that are not positioned along the common light path region and that are positioned along the imaging path and not the illumination path.

6. The display device of claim 5 , wherein the one or more imaging optical elements are configured to direct the image light toward an input grating of a waveguide.

7. The display device of claim 1 , further comprising one or more illumination optical elements that are not positioned along the common light path region and that are positioned along the illumination path and not the imaging path.

8. The display device of claim 1 , where at least one optical element of the two or more optical elements is polarization-sensitive, such that the at least one optical element is configured to treat light of a first polarization differently than light of a second polarization.

9. The display device of claim 1 , where the two or more optical elements apply optical power to the image light.

10. The display device of claim 1 , further comprising an aperture baffle positioned along the imaging path.

11. The display device of claim 1 , wherein the partially cut lens has a semi-circular shape and is constructed by removing a portion of a whole lens.

12. The display device of claim 1 , wherein the partially cut lens includes a portion that receives and treats illumination light, and a second portion that receives and treats image light.

13. The display device of claim 1 , wherein the partially cut lens includes two or more regions of differing optical power.

14. At a display device, a method of forming an image, the method comprising:
emitting, from a light source, illumination light along an illumination path, the illumination light used to achieve illumination of a spatial light modulator;
at the spatial light modulator, modulating the illumination light and emitting the modulated illumination light as image light along an imaging path, wherein at least a portion of the illumination path and at least a portion of the imaging path extend through a common light path region extending along an optical axis of the display device; and
two or more optical elements positioned within the common light path region, (1) guiding the illumination light as the illumination light travels through the common light path region toward the spatial light modulator, and (2) shaping the image light as the image light travels through the common light path region, the two or more optical elements including at least one element to transmit the illumination light prior to modulation by the spatial light modulator, and a series of two or more lenses to transmit the image light after modulation by the spatial light modulator, the two or more lenses including a partially cut lens positioned within the common light path region.

15. The method of claim 14 , wherein the two or more optical elements include a beam splitter.

16. The method of claim 14 , further comprising, at one or more imaging optical elements that are not positioned along the common light path region and that are positioned along the imaging path and not the illumination path, directing image light toward an input grating of a waveguide.

17. The method of claim 14 , wherein at least one optical element of the one or more imaging optical elements is polarization-sensitive, further comprising, at the at least one optical element, treating light of a first polarization differently than light of a second polarization.

18. A mixed reality display device, comprising:
a frame;
a display engine, comprising:
a light source configured to emit illumination light along an illumination path, the illumination light used to achieve illumination of a spatial light modulator;
the spatial light modulator configured to receive and modulate the illumination light, and emit the modulated illumination light as image light along an imaging path, wherein at least a portion of the illumination path and at least a portion of the imaging path extend through a common light path region extending along an optical axis of the display device; and
two or more optical elements positioned within the common light path region, at least one optical element of the two or more optical elements being configured to (1) guide the illumination light as the illumination light travels through the common light path region toward the spatial light modulator, and (2) shape the image light as the image light travels through the common light path region, the two or more optical elements including a lens within the common light path region configured to both transmit the illumination light prior to modulation by the spatial light modulator, and also transmit the image light after modulation by the spatial light modulator, and the two or more optical elements including a partially cut lens positioned within the common light path region;

one or more displays configured to generate imagery based on the image light; and
a waveguide configured to receive the image light and direct the image light toward the one or more displays.

19. The mixed reality display device of claim 18 , further comprising one or more imaging optical elements that are not positioned along the common light path region and that are positioned along the imaging path and not the illumination path.

Assignees

• Microsoft Technology Licensing Llc

Inventors

• Chatterjee Ishan
• Reshidko Dmitry

Classifications

• G02B27/0172 Primary

  characterised by optical features · CPC title

• G02B26/0833

  the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD (G02B26/0825 takes precedence; micromechanical devices in general B81B) · CPC title

• G02F1/136277

  formed on a semiconductor substrate, e.g. of silicon · CPC title

• G02B6/26

  Optical coupling means (G02B6/36, G02B6/42 take precedence) · CPC title

• G02B2027/0178

  Eyeglass type (eyeglass details G02C) · CPC title