System, method, and non-transitory computer-readable storage media related wearable pupil-forming display apparatus with variable opacity and dynamic focal length adjustment
A wearable display apparatus has an image generator that is energizable to form a 2D image; a partially transmissive mirror having a curved reflective surface; a beam splitter disposed to reflect light toward the curved mirror surface; and an optical image relay that is configured to relay the formed 2D image at the image generator to a curved focal surface of the partially transmissive mirror, wherein the curved focal surface is defined between the curved reflective surface of the partially transmissive mirror and the beam splitter, wherein the relay, curved mirror, and beam splitter are configured to form an exit pupil for viewing the generated 2D image as an optical virtual image; and a spatial light modulator configured with addressable array of pixels for selectively changing opacity for visible light from the object field according to dimensions of the generated 2D image.
1. A wearable display apparatus comprising:
(a) an image generator that is energizable to form a generated 2D image;
(b) a partially transmissive mirror having a curved reflective surface;
(c) a beam splitter disposed to reflect light toward the curved reflective surface;
(d) an optical image relay that is configured to relay the formed 2D image at the image generator to a curved focal surface of the partially transmissive mirror,
wherein the curved focal surface is defined between the curved reflective surface of the partially transmissive mirror and the beam splitter,
wherein the optical image relay comprises a prism having a plano-aspheric lens in optical contact against a prism input surface and configured to guide image-bearing light from the image generator toward a folding surface of the prism and to form an aperture stop within the prism,
wherein the relay, the partially transmissive mirror, and beam splitter provide a near-eye catadioptric pupil-forming imaging system configured to form an exit pupil for viewing the generated 2D image as an optical virtual image superimposed against an object scene; and
(e) a spatial light modulator disposed between the partially transmissive mirror and the object scene and configured with an addressable array of pixels for selectively changing opacity for visible light from the object scene.
2. The apparatus of claim 1 wherein the spatial light modulator forms a parallax light-field display rendering the optical virtual image perceptible as a three-dimensional image.
3. The apparatus of claim 1 wherein the spatial light modulator is formed from layers deposited on the partially transmissive mirror.
4. The apparatus of claim 1 wherein the spatial light modulator is spaced apart from the curved mirror.
5. The apparatus of claim 1 wherein spatial light modulator opacity to visible light from the object field can be changed according to a sensed signal from a viewer instruction entry.
6. The apparatus of claim 1 wherein the command is acquired as an audible command.
7. The apparatus of claim 1 wherein the command is acquired by hand gesture recognition.
8. The apparatus of claim 1 wherein the command is manually entered by the viewer.
9. The apparatus of claim 1 wherein the selectively changed opacity is provided by diffusion.
10. The apparatus of claim 1 wherein the command is acquired according to a change in head tilt.
11. A method comprising:
a) energizing an electroluminescent image generator to emit light forming a generated 2D image;
b) relaying the image generator to a curved surface at a focal plane of a partially transmissive curved mirror,
wherein relaying further comprises directing an image-bearing light from the image generator to a prism having a plano-aspheric lens in optical contact against a prism input surface, wherein the plano-aspheric lens is configured to guide image-bearing light from the image generator toward a folding surface of the prism and to form an aperture stop within the prism,
wherein the curved surface at the focal plane is conjugate to the image generator and wherein the focal plane of the partially transmissive curved mirror is formed using a beam splitter that is disposed to reflect light toward the partially transmissive curved mirror surface,
wherein the relay, the partially transmissive curved mirror surface, and beam splitter are configured to form an exit pupil for viewing the generated 2D image as an optical virtual image superimposed on an object field;
c) obtaining image content from the object field through a spatial light modulator that is disposed between the partially transmissive curved mirror and the object field and is configured with addressable array of pixels for selectively changing opacity for visible light from the object field;
and
d) energizing the spatial light modulator and modulating opacity over the object field according to command entry by a viewer,
wherein the spatial light modulator forms a parallax light-field display rendering the optical virtual images viewable as three-dimensional images.
12. The method of claim 11 further comprising tracking eye gaze of a viewer and changing a focal length for the optical virtual image according to eye gaze tracking.
13. The apparatus of claim 11 wherein the command entry is an audible command.
14. The apparatus of claim 11 wherein the command entry is a hand gesture.
15. The apparatus of claim 11 wherein the command entry is manually entered by the viewer.
16. The apparatus of claim 11 wherein the selectively changed opacity is provided by diffusion.
17. The apparatus of claim 11 wherein the command entry relates to a change in head tilt.
18. A wearable display apparatus comprising:
(a) an image generator that is energizable to form a generated 2D image;
(b) a partially transmissive mirror having a curved reflective surface;
(c) a polarization beam splitter disposed to reflect light toward the curved reflective surface;
(d) an optical image relay that is configured to relay the generated 2D image at the image generator to a curved focal surface of the partially transmissive mirror,
wherein the relay comprises a prism having a plano-aspheric lens in optical contact against a prism input surface and configured to guide image-bearing light from the image generator toward a folding surface of the prism and to form an aperture stop within the prism,
wherein the curved focal surface is defined between the curved reflective surface of the partially transmissive mirror and the polarization beam splitter,
wherein the relay, curved mirror, and polarization beam splitter are configured to form an exit pupil for viewing the generated 2D image as an optical virtual image superimposed against an object field;
and
(e) a sensor configured to generate a sensor signal in response to an audible command, head position, or hand gesture instruction entered by a viewer,
wherein a surface of the curved mirror is conditioned with one or more addressable areas for selective control of opacity for visible light from the object field, according to the sensor signal.
19. A wearable display apparatus for a viewer,
the apparatus having: a left-eye imaging section and a right-eye imaging section, wherein each imaging section comprises:
(a) an image generator that is energizable to form a generated 2D image;
(b) a partially transmissive mirror having a curved reflective surface;
(c) a beam splitter disposed to reflect light toward the curved reflective surface;
(d) an optical image relay that is configured to relay the generated 2D image at the image generator to a curved focal surface of the partially transmissive mirror,
wherein the curved focal surface is defined between the curved reflective surface of the partially transmissive mirror and the beam splitter,
wherein the relay comprises a prism having a plano-aspheric lens in optical contact against a prism input surface and configured to guide image-bearing light from the image generator toward a folding surface of the prism and to form an aperture stop within the prism,
wherein the optical image relay, partially transmissive mirror, and beam splitter are configured to form an exit pupil for viewing the generated 2D image as an optical virtual image superimposed against an object field;
(e) a spatial light modulator disposed between the partially transmissive mirror and the object field and configured with an addressable array of pixels for selectively changing opacity for visible light from the object field;
(f) an eye-gaze detection apparatus that is configured to identify at least a direction of vision of the viewer; and
(g) a focal length control apparatus that is configured to determine a focal length according to the identified direction of viewer vision and to adjust the focal length for forming the optical virtual image,
wherein the selectively changed opacity alternates between the spatial light modulator for the left-eye imaging section and the spatial light modulator for the right-eye imaging section.
20. The apparatus of claim 19 wherein the focal length control apparatus comprises a piezoelectric actuator.
21. The apparatus of claim 19 wherein the spatial light modulator is a liquid crystal device.
22. The apparatus of claim 19 wherein the combined image content from left- and right-eye imaging sections forms three-dimensional images or video.