See-through computer display systems

• US 9,720,227 B2
• Filed: 12/05/2014
• Issued: 08/01/2017
• Est. Priority Date: 01/21/2014
• Status: Active Grant

• Current Assignee: Mentor Acquisition One, LLC (Magic Leap, Inc.)
• Original Assignee: Osterhout Design Group
• Inventors: Bietry, Joseph, Border, John N.
• Primary Examiner(s): CHOI, WILLIAM C
• Application Number:
  US14/561,990
• Publication Number:
  US 20150205129A1
• Time in Patent Office: 970 Days
• Field of Search: 359630, 345 7- 9
• 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 2027/015 involving arrangement aiming to get less bulky devices
• CPC Class Codes: G02B 2027/0152 involving arrangement aiming to get lighter or better balanced devices
• CPC Class Codes: G02B 2027/0174 holographic
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 2027/0187 slaved to motion of at least a part of the body of the user, e.g. head, eye
• CPC Class Codes: G02B 2027/0194 with combiner of laminated type, for optical or mechanical aspects
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• 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 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 27/0176 characterised by mechanical features
• CPC Class Codes: G02B 27/10 Beam splitting or combining systems polarising systems G02B27/28; mixing and splitting light signals using optical waveguides G02B6/28; beam shaping, e.g. changing the cross-sectional area, by dividing or superposing multiple light beams G02B27/0905
• CPC Class Codes: G02B 27/1033 having a single light modulator for all colour channels
• CPC Class Codes: G02B 27/144 using partially transparent surfaces without spectral selectivity G02B27/147 takes precedence
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: H04N 23/51 Housings
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils

Abstract

Aspects of the present invention relate to a compact optics module for a head mounted display including a DLP image source comprising a polarized light source providing illumination light, a flat reflective polarizer to reflect the illumination light toward the DLP image source and transmit image light, wherein the illumination light is provided at an angle to the DLP, a quarter wave retarder to change the polarization state of the illumination light as it is reflected by the DLP image source thereby providing image light, at least one light trap to absorb a portion of off-state image light, a lens element to provide a viewable field of view of on-state image light in an image displayed by the DLP image source, and a combiner to reflect the on-state image light toward a user'"'"'s eye and provide a see-through view of a surrounding environment.

Claims

1. A compact optics module for a head mounted display including a digital light processor (“

DLP”

) image source comprising;

a polarized light source providing illumination light;

a flat reflective polarizer to reflect the illumination light toward the DLP image source and transmit image light, wherein the illumination light is provided at an angle to the DLP;

a quarter wave retarder to change the polarization state of the illumination light as it is reflected by the DLP image source thereby providing image light;

at least one light trap to absorb a portion of off-state image light;

a lens element to provide a viewable field of view of on-state image light in an image displayed by the DLP image source; and

a combiner to reflect the on-state image light toward a user'"'"'s eye and provide a see-through view of a surrounding environment;

wherein the lens element includes at least one diffractive surface.

2. The compact optics module of claim 1, wherein the flat reflective polarizer extends beyond a lens element surface.

3. The compact optics module of claim 1, wherein the process of reflecting the illumination light and reflecting the on-state image light provides a multiply folded optical path that reduces the thickness and height of the compact optics module.

4. The compact optics module of claim 1, further comprising a rear optical element selected from the group consisting of a protective plate and a prescriptive optic.

5. The compact optics module of claim 4, wherein the protective plate is connected to a sidewall of a housing of the compact optics module.

6. The compact optics module of claim 1, wherein the reflective polarizer reflects light of one polarization state and transmits light of the other polarization state.

7. The compact optics module of claim 1, wherein the light trap is recessed into a wall of a housing of the compact optics module.

8. The compact optics module of claim 1, wherein the light trap comprises a coating of black paint.

9. The compact optics module of claim 1, wherein the light trap comprises at least one of a mask and a guard to block scattered light and prevent the light trap from being viewed adjacent to a displayed image.

10. The compact optics module of claim 1, wherein the combiner includes a holographic mirror.

11. The compact optics module of claim 10, wherein if a monochrome image is desired, a single wavelength reflection design for the holographic mirror is included on a surface of the combiner.

12. The compact optics module of claim 11, wherein if a multiple color image is desired, a multiple wavelength holographic mirror is included on a surface of the combiner.

15. The compact optics module of claim 4, wherein the light source is positioned behind the second flat reflective polarizer.

13. A compact optics module for a head mounted display including a digital light processor (“

DLP”

) image source comprising;

a polarized light source providing illumination light;

a flat reflective polarizer to reflect the illumination light toward the DLP image source and transmit image light, wherein the illumination light is provided at an angle to the DLP;

a quarter wave retarder to change the polarization state of the illumination light as it is reflected by the DLP image source thereby providing image light;

at least one light trap to absorb a portion of off-state image light;

a lens element to provide a viewable field of view of on-state image light in an image displayed by the DLP image source;

a combiner to reflect the on-state image light toward a user'"'"'s eye and provide a see-through view of a surrounding environment; and

an absorptive polarizer adjacent to the lens element and oriented to absorb incident illumination light and transmit image light.

14. A compact optics module for a head mounted display including a digital light processor (“

DLP”

) image source comprising;

a polarized light source providing illumination light;

a flat reflective polarizer to reflect the illumination light toward the DLP image source and transmit image light, wherein the illumination light is provided at an angle to the DLP;

a quarter wave retarder to change the polarization state of the illumination light as it is reflected by the DLP image source thereby providing image light;

at least one light trap to absorb a portion of off-state image light;

a lens element to provide a viewable field of view of on-state image light in an image displayed by the DLP image source; and

a combiner to reflect the on-state image light toward a user'"'"'s eye and provide a see-through view of a surrounding environment;

wherein the flat reflective polarizer is adjacent the lens element; and

the compact optics module further comprises a second flat reflective polarizer that transmits illumination light and reflects image light toward the lens element.

16. A compact optics module for a head mounted display including a digital light processor (“

DLP”

) image source comprising;

a polarized light source providing illumination light;

a flat reflective polarizer to reflect the illumination light toward the DLP image source and transmit image light, wherein the illumination light is provided at an angle to the DLP;

a quarter wave retarder to change the polarization state of the illumination light as it is reflected by the DLP image source thereby providing image light;

at least one light trap to absorb a portion of off-state image light;

a lens element to provide a viewable field of view of on-state image light in an image displayed by the DLP image source; and

a combiner to reflect the on-state image light toward a user'"'"'s eye and provide a see-through view of a surrounding environment;

wherein the see-through view of the surrounding environment includes unpolarized light and the combiner transmits over 50% of the unpolarized light.

17. A compact optics module for a head mounted display including a digital light processor (“

DLP”

) image source comprising;

a polarized light source providing illumination light;

a flat reflective polarizer to reflect the illumination light toward the DLP image source and transmit image light, wherein the illumination light is provided at an angle to the DLP;

a quarter wave retarder to change the polarization state of the illumination light as it is reflected by the DLP image source thereby providing image light;

at least one light trap to absorb a portion of off-state image light;

a lens element to provide a viewable field of view of on-state image light in an image displayed by the DLP image source; and

a combiner to reflect the on-state image light toward a user'"'"'s eye and provide a see-through view of a surrounding environment;

wherein the combiner is a partial mirror.

18. A compact optics module for a head mounted display including a digital light processor (“

DLP”

) image source comprising;

a polarized light source providing illumination light;

a flat reflective polarizer to reflect the illumination light toward the DLP image source and transmit image light, wherein the illumination light is provided at an angle to the DLP;

a quarter wave retarder to change the polarization state of the illumination light as it is reflected by the DLP image source thereby providing image light;

at least one light trap to absorb a portion of off-state image light;

a lens element to provide a viewable field of view of on-state image light in an image displayed by the DLP image source; and

a combiner to reflect the on-state image light toward a user'"'"'s eye and provide a see-through view of a surrounding environment;

wherein the combiner is a notch mirror.

19. The compact optics module of claim 18, wherein the notch mirror is a tristimulus notch mirror.