Systems and methods for producing wide field-of-view holographic displays
View Patent ↗Hologram recording devices and techniques can be employed to produce wide-field-of-view holograms. In one embodiment, a specialized lens is used to couple an object beam into a holographic recording material without substantially changing the angle of incidence of the object beam. When displayed, images from holograms recorded using technique can have a field-of-view greater than that of the object beam. In another embodiment, one or more aspheric reflective surfaces are used to couple an object beam into a holographic recording material at relatively steep angles.
1. An apparatus comprising:
a light source that produces a coherent beam;
a beam splitter that splits the coherent beam into an object beam and a reference beam;
an object beam optical system for directing the object beam to interfere with the reference beam at a holographic recording material, wherein the object beam optical system includes:
a spatial light modulator for intensity modulating the object beam;
a collimating lens configured to collimate the object beam; and
an aspheric reflector configured to focus the collimated object beam to a location within the holographic recording material, wherein the aspheric reflector is positioned with respect to the holographic recording material so that a focus of the aspheric reflector substantially coincides with the holographic recording material;
a reference beam optical system for directing the reference beam to interfere with the object beam at the holographic recording material; and
a computer coupled to the spatial light modulator and programmed to control delivery of a rendered image to the spatial light modulator.
2. The apparatus of claim 1 wherein the aspheric reflector includes a first aspheric mirror surface positioned to reflect and focus the collimated object beam at the location within the holographic recording material.
3. The apparatus of claim 2 wherein the aspheric mirror surface is parabolic.
4. The apparatus of claim 1 wherein the aspheric reflector further comprises:
a first aspheric mirror surface; and
a second aspheric mirror surface, wherein the first aspheric mirror surface is positioned to reflect the collimated object beam toward the second aspheric mirror surface, and wherein the second aspheric mirror surface is positioned to reflect and focus the object beam at the location within the holographic recording material.
5. The apparatus of claim 4 wherein the first aspheric mirror surface is parabolic, and wherein the second aspheric mirror surface is elliptical.
6. The apparatus of claim 4 wherein a focus of the first aspheric mirror surface substantially aligned with a focus of the second aspheric mirror surface.
7. The apparatus of claim 1 wherein the light source is at least one of a pulsed laser and a continuous wave laser.
8. The apparatus of claim 1 further comprising:
a material holder for holding the holographic recording material; and
a material holder translation system operable to position the material holder holding holographic recording material.
9. An apparatus comprising:
a light source that produces a coherent beam;
a beam splitter that splits the coherent beam into an object beam and a reference beam;
an object beam optical system for directing the object beam to interfere with the reference beam at a holographic recording material, wherein the object beam optical system includes:
a collimating lens configured to collimate the object beam; and
an aspheric reflector configured to focus the collimated object beam to a location within the holographic recording material wherein the aspheric reflector is positioned with respect to the holographic recording material so that a focus of the aspheric reflector substantially coincides with the holographic recording material; and wherein the aspheric reflector includes an aperture through which the reference beam can pass;
a reference beam optical system for directing the reference beam to interfere with the object beam at the holographic recording material.
10. An apparatus comprising:
a light source that produces a coherent beam;
a beam splitter that splits the coherent beam into an object beam and a reference beam;
an object beam optical system for directing the object beam to interfere with the reference beam at a holographic recording material, wherein the object beam optical system includes:
a collimating lens configured to collimate the object beam; and
an aspheric reflector configured to focus the collimated object beam to a location within the holographic recording material, wherein the aspheric reflector is positioned with respect to the holographic recording material so that a focus of the aspheric reflector substantially coincides with the holographic recording material; and wherein the aspheric reflector includes at least one substantially non-reflective portion through which the reference beam can be transmitted;
a reference beam optical system for directing the reference beam to interfere with the object beam at the holographic recording material.
11. An apparatus comprising:
a light source that produces a coherent beam;
a beam splitter that splits the coherent beam into an object beam and a reference beam;
an object beam optical system for directing the object beam to interfere with the reference beam at a holographic recording material, wherein the object beam optical system includes:
a collimating lens configured to collimate the object beam;
an aspheric reflector configured to focus the collimated object beam to a location within the holographic recording material, wherein the aspheric reflector is positioned with respect to the holographic recording material so that a focus of the aspheric reflector substantially coincides with the holographic recording material; and;
an object beam optics translation system configured to translate the aspheric reflector with respect to the holographic recording material; and
a reference beam optical system for directing the reference beam to interfere with the object beam at the holographic recording material.
12. A method comprising:
providing a holographic recording material;
providing data for at least one hogel to a spatial light modulator;
intensity modulating an object beam from a laser with the spatial light modulator;
reflecting the object beam from an aspheric reflector, wherein the aspheric reflector is positioned with respect to the holographic recording material so that a focus of the aspheric reflector substantially coincides with the holographic recording material; and
exposing a portion of the holographic recording material to an interference pattern formed by a reference beam from the laser and the object beam from the laser.
13. The method of claim 12 further comprising:
collimating the object beam before the reflecting the object beam from the aspheric reflector.
14. The method of claim 12 wherein the aspheric reflector includes a first aspheric mirror surface positioned to reflect and focus the object beam at the location within the holographic recording material.
15. The method of claim 14 wherein the aspheric mirror surface is parabolic.
16. The method of claim 12 wherein the aspheric reflector further comprises:
a first aspheric mirror surface; and
a second aspheric mirror surface, wherein the first aspheric mirror surface is positioned to reflect the object beam toward the second aspheric mirror surface, and wherein the second aspheric mirror surface is positioned to reflect and focus the object beam at the location within the holographic recording material.
17. The method of claim 16 wherein the first aspheric mirror surface is parabolic, and wherein the second aspheric mirror surface is elliptical.
18. The method of claim 16 further comprising:
positioning a focus of the first aspheric mirror surface to substantially overlap with a focus of the second aspheric mirror surface.
19. The method of claim 12 wherein the aspheric reflector includes an aperture through which the reference beam can pass.
20. The method of claim 12 wherein the aspheric reflector includes at least one substantially non-reflective portion through which the reference beam can be transmitted.
21. The method of claim 12 further comprising:
holding the holographic recording material in a material holder; and
translating the aspheric reflector with respect to the holographic recording material.
22. The method of claim 12 further comprising:
holding the lens in a first position; and
translating the holographic recording material with respect to the aspheric reflector.
23. The method of claim 12 further comprising:
forming at least one hogel in the holographic recording material, wherein the at least one hogel corresponds to the data for at least one hogel provided to the spatial light modulator.
24. The method of claim 12 further comprising:
transmitting the data for at least one hogel to the spatial light modulator using a computer coupled to the spatial light modulator, wherein the data for at least one hogel corresponds to a rendered image.
25. The method of claim 12 wherein the laser is at least one of a pulsed laser and a continuous wave laser.