Near eye head up display system and method with fixed combiner

• US 10,732,407 B1
• Filed: 01/10/2014
• Issued: 08/04/2020
• Est. Priority Date: 01/10/2014
• Status: Active Grant

• Current Assignee: Rockwell Collins, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Rockwell Collins, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Wood, Robert B., Brown, Robert D.
• Primary Examiner(s): Chang, Audrey Y
• Application Number:
  US14/152,756
• Time in Patent Office: 2,398 Days
• Field of Search: 359630, 359631, 359632, 359 15, 359569, 359567, 359 34, 345 7, 349115
• CPC Class Codes: G02B 2027/0132 comprising binocular systems
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 27/0103 comprising holographic elements
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 5/18 Diffraction gratings holographic optical elements G02B5/32, G03H; integrally combined with optical fibres G02B6/02057; for coupling light guides G02B6/34; integrally combined with optical integrated light guides G02B6/12; grating systems G02B27/44
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00

Abstract

A display, such as a fixed head up display, can be configured as a near eye display. Display can be used in the environment of the user. Display includes an image source fixed with the environment and a combiner system. The combiner system is configured to be disposed at a near eye location with respect to the user. The combiner system includes at least one diffraction grating member. The diffraction grating member has an input and for receiving an image from the image source and a combiner end for receiving light from the real world scene. The image received at the input end and the light received from the outside scene are provided to the user.

Claims

1. A near eye display comprising:

a projector comprising a polarizing beam splitter coupled with a collimating mirror and configured to provide collimated light, wherein the projector is configured to perform catadioptric collimation and comprises an illuminator and an illuminator mirror on a first side of the polarizing beam splitter and between the illuminator and the polarizing beam splitter to receive illuminator light from the illuminator and reflect the illuminator light to the polarizing beam splitter, wherein an image source is disposed on a second side of the polarizing beam splitter opposite the first side, wherein the collimating mirror is attached to a third side of the polarizing beam splitter, the third side being a side farthest from the user under normal operation, a planoconvex lens is disposed between the illuminator mirror and the first side of the polarizing beam splitter, a convex surface of the planoconvex lens facing the polarizing beam splitter, and a collimating lens is disposed between the image source and the second side of the polarizing beam splitter; and

a combiner system configured to be disposed at a near eye location with respect to a user, the combiner system having an input end including a first diffraction grating for receiving the collimated light from the projector, and a combiner end including a second diffraction grating for receiving light from an outside scene and providing the collimated light received at the input end and the light received from the outside scene to the user, and an intermediate portion between the input end and the combiner end free of diffraction gratings, the intermediate portion configured to operate as a waveguide between the input end and the combiner end;

wherein the combiner system is unattached to the user and fixed at a distance within four inches of eyes of the user and is provided in front of both of the eyes of the user when in operation, the projector being disposed at the input end of the combiner system, the input end being horizontally opposite from the combiner end of the combiner system, wherein the projector is attached to the combiner system at a fourth side of the polarizing beam splitter opposite the third side,

the combiner system including a first area associated with input of the collimated light at the input end and a second area associated with output of light at the combiner end, the first area being less than the second area such that the combiner system is configured to expand a pupil horizontally as the collimated light travels from the input end to the combiner end, and

the combiner system being configured to provide full binocular overlap at the combiner end via the pupil in a lateral eye box associated with the pupil such that information is displayed by the combiner system to both eyes of the user simultaneously,

wherein the combiner system utilizes the waveguide and diffraction gratings such that the combiner system operates according to a periscopic effect where input rays of the collimated light at the input end are parallel to output rays of the light provided to the user.

2. The display of claim 1, wherein the diffraction gratings are surface gratings or volumetric holograms.

3. The display of claim 2, wherein the diffraction gratings are holograms.

4. The display of claim 3, wherein the waveguide is a glass material.

5. The display of claim 4, wherein the waveguide has a rectangular shape extending laterally to be positioned in front of the eyes of the user and extending vertically in a dimension smaller than a lateral dimension of the waveguide.

6. The display of claim 1, wherein the image source is a LCOS display.

7. The display of claim 6, wherein optics for catadioptric collimation are provided with the LCOS display.

8. The display of claim 1, wherein the projector is configured such that the illuminator light enters the polarizing beam splitter via the first side, travels through second side of the polarizing beam splitter to the image source, is reflected by the image source towards an interface of the polarizing beam splitter, is reflected by the interface of the polarizing beam splitter towards the collimating mirror through the third side of the polarizing beam splitter, and is provided by the collimating mirror through the polarizing beam splitter to the combiner system to provide the collimated light.

9. A mounted device comprising:

a projector configured to provide a near collimated or collimated image, the projector comprising a polarizing beam splitter coupled with a collimating mirror and configured to provide collimated light, wherein the projector is configured to perform catadioptric collimation and comprises an illuminator and an illuminator mirror on a first side of the polarizing beam splitter and between the illuminator and the polarizing beam splitter to receive illuminator light from the illuminator and reflect the illuminator light to the polarizing beam splitter, wherein an image source is disposed on a second side of the polarizing beam splitter opposite the first side, wherein the collimating mirror is attached to a third side of the polarizing beam splitter, the third side being a side farthest from the user under normal operation, a planoconvex lens is disposed between the illuminator mirror and the first side of the polarizing beam splitter, a convex surface of the planoconvex lens facing the polarizing beam splitter, and a collimating lens is disposed between the image source and the second side of the polarizing beam splitter; and

a combiner comprising a first diffraction grating member wherein the first diffraction grating member has a length of four inches or more, a width of 2 inches or less and a thickness of 0.5 inches or less and configured so that a first end of the first diffraction grating member can be provided in front of eyes of a user and a second end of the first diffraction grating member receives the collimated or near collimated image, wherein the projector is attached to the combiner at a fourth side of the polarizing beam splitter opposite the third side,

wherein the first end receives light from a real world scene, the first end is associated with a first area for outputting light to the eyes of the user, and the second end is associated with a second area for receiving the collimated or near collimated image, the second area being less than the first area such that the first diffraction grating member provides horizontal pupil expansion,

wherein the first end is horizontally opposite to the second end and the real world scene is viewed at a location of the horizontal pupil expansion, wherein full binocular overlap is provided in a lateral eye box associated with the horizontal pupil expansion such that information is provided to both eyes of the user simultaneously, wherein the combiner operates according to a periscopic effect where input rays of the collimated light are parallel to output rays of the light outputted to the eyes of the user.

10. The mounted device of claim 9, wherein the projector comprising a Liquid Crystal On Silicon (LCOS) source using high magnification provides the collimated or near collimated image.

11. The mounted device of claim 10, wherein an assembly including the LCOS source is attached to the second end of the first diffraction grating member.

12. The mounted device of claim 11, wherein the second end extends away from a head of the user when the user looks through the first end.

13. A method of providing guidance information to a pilot'"'"'s eyes in an aircraft, the method comprising:

providing collimated or near collimated light indicative of the guidance information from a display to a first end of a passive element disposed within three inches of the pilot'"'"'s eyes using a polarizing beam splitter coupled with a collimating mirror, wherein the display is configured to perform catadioptric collimation and comprises an illuminator and an illuminator mirror on a first side of the polarizing beam splitter and between the illuminator and the polarizing beam splitter to receive illuminator light from the illuminator and reflect the illuminator light to the polarizing beam splitter, wherein an image source is disposed on a second side of the polarizing beam splitter opposite the first side, wherein the collimating mirror is attached to a third side of the polarizing beam splitter, the third side being a side farthest from the user under normal operation, the passive element being a combiner fixed relative to the pilot'"'"'s eyes, a fourth side of the display opposite the third side being fixed to the combiner during normal operation, a planoconvex lens is disposed between the illuminator mirror and the first side of the polarizing beam splitter, a convex surface of the planoconvex lens facing the polarizing beam splitter, and a collimating lens is disposed between the image source and the second side of the polarizing beam splitter; and

combining light from a real world scene with the collimated or near collimated light using the passive element to output the combined light at a second end of the passive element, wherein the first end is associated with a first area that is less than a second area associated with the second end such that the passive element is configured to provide horizontal pupil expansion to the collimated or near collimated light and the real world scene is viewed at a location of the horizontal pupil expansion, wherein full binocular overlap is provided in a lateral eye box associated with the horizontal pupil expansion such that information is displayed to both of the pilot'"'"'s eyes simultaneously, wherein the passive element causes a periscopic effect where input rays of the collimated or near collimate light are parallel to output rays at the location of the horizontal pupil expansion.

14. The method of claim 13, wherein the display is a highly magnified liquid crystal on silicon (LCOS) display.

15. The method of claim 13, wherein the passive element is a waveguide substrate.

16. The method of claim 13, wherein the illuminator and the collimating mirror are in a package.