Method and system for high resolution digitized display
A method and system for increasing dynamic digitized wavefront resolution, i.e., the density of output beamlets, can include receiving a single collimated source light beam and producing multiple output beamlets spatially offset when out-coupled from a waveguide. The multiple output beamlets can be obtained by offsetting and replicating a collimated source light beam. Alternatively, the multiple output beamlets can be obtained by using a collimated incoming source light beam having multiple input beams with different wavelengths in the vicinity of the nominal wavelength of a particular color. The collimated incoming source light beam can be in-coupled into the eyepiece designed for the nominal wavelength. The input beams with multiple wavelengths take different paths when they undergo total internal reflection in the waveguide, which produces multiple output beamlets.
1. A wearable display device comprising:
a pair of temple arms;
a pair of projector assemblies, each of the pair of projector assemblies being integrated into one of the pair of temple arms, wherein each of the pair of projector assemblies includes a light source for providing a collimated incoming light beam including a plurality of input light beams having different wavelengths;
a pair of optical devices, each of the pair of optical devices including a first prism, a second prism, a third prism, and a fourth prism, wherein each optical device is configured to receive the collimated incoming light beam and output a two-dimensional array of beamlets, wherein:
the first prism and the second prism are separated by a first air gap, a first surface of the first prism and a second surface of the second prism being disposed in parallel and adjacent to each other across the first air gap, the first surface being partially reflective and the second surface being substantially totally reflective, and
the third prism and the fourth prism are separated by a second air gap, a third surface of the third prism and a fourth surface of the fourth prism being disposed in parallel and adjacent to each other across the second air gap, the third surface being partially reflective and the fourth surface being substantially totally reflective;
the third prism and the fourth prism are disposed adjacent to and rotated with respect to the first prism and the second prism;
a pair of main displays, wherein each of the pair of main displays comprises a waveguide including a wavelength-sensitive input coupling element and an output coupling element;
wherein the waveguide is configured for:
in-coupling the two-dimensional array of beamlets into the waveguide using the wavelength-sensitive input coupling element;
propagating the two-dimensional array of beamlets by total internal reflection (TIR), each beamlet propagating along a different path; and
outputting multiple groups of output light beamlets using the output coupling element, each group of output light beamlets including a portion of each of the two-dimensional array of beamlets propagating in the waveguide by total internal reflection.
2. The wearable display device of claim 1 , wherein the waveguide is configured for a nominal wavelength of a color, and the plurality of input light beams have wavelengths in the vicinity of the nominal wavelength.
3. The wearable display device of claim 1 , wherein the collimated incoming light beam is provided by a fiber scanner.
4. The wearable display device of claim 1 , further comprising an eye lens for focusing the multiple groups of output light beamlets for display.
5. The wearable display device of claim 1 , wherein the collimated incoming light beam is incident on the wavelength-sensitive input coupling element at normal incidence.
6. The wearable display device of claim 1 , wherein the wavelength-sensitive input coupling element is coupled to a first surface of the waveguide and the output coupling element is coupled to a second surface of the waveguide opposite to the first surface.
7. A method for displaying an image, the method comprising:
providing a wearable display device including a pair of temple arms;
providing a pair of main displays, wherein each of the pair of main displays comprises a waveguide including a wavelength-sensitive input coupling element;
providing a pair of projector assemblies, each of the pair of projector assemblies being integrated into one of the pair of temple arms, wherein each of the pair of projector assemblies includes a light source for providing a collimated incoming light beam including a plurality of input light beams having different wavelengths;
providing a pair of optical devices, each optical device of the pair of optical devices including a first prism, a second prism, a third prism, and a fourth prism, wherein:
each of the first prism, the second prism, the third prism, and the fourth prism are right triangle prisms;
a first, partially reflective surface of the first prism and a second, totally reflective surface of the second prism are disposed in parallel and adjacent to each other; and
a third, partially reflective surface of the third prism and a fourth, totally reflective surface of the fourth prism are disposed in parallel and adjacent to each other; and
the third prism and the fourth prism are disposed adjacent to and rotated with respect to the first prism and the second prism;
receiving, at each optical device, the collimated incoming light beam;
outputting, from each optical device, a two-dimensional array of beamlets:
in-coupling the two-dimensional array of beamlets into the waveguide using the wavelength-sensitive input coupling element;
propagating the two-dimensional array of beamlets by total internal reflection (TIR), each beamlet propagating along a different path;
providing an output coupling element optically coupled to the waveguide; and
outputting multiple groups of output light beamlets using the output coupling element, each group of output light beamlets including a portion of each of the two-dimensional array of beamlets propagating in the waveguide by total internal reflection.
8. The method of claim 7 , wherein the waveguide is configured for a nominal wavelength of a color, and the plurality of input light beams have wavelengths in the vicinity of the nominal wavelength.
9. The method of claim 7 , wherein the collimated incoming light beam is provided by a fiber scanner.
10. The method of claim 7 , further comprising:
providing an eye lens for focusing the multiple groups of output light beamlets for display.
11. The method of claim 7 , wherein the collimated incoming light beam is incident on the wavelength-sensitive input coupling element at normal incidence.
12. The method of claim 7 , wherein the wavelength-sensitive input coupling element is coupled to a first surface of the waveguide and the output coupling element is coupled to a second surface of the waveguide opposite to the first surface.
13. The wearable display device of claim 1 , wherein the first prism and the second prism are configured to convert the collimated incoming light beam into a first plurality of spatially offset beamlets.
14. The wearable display device of claim 13 , wherein the third prism and the fourth prism are configured to convert the first plurality of spatially offset beamlets into the two-dimensional array of beamlets.
15. The wearable display device of claim 13 , wherein an output surface of the first prism is parallel to a first side surface of the third prism, wherein the first plurality of spatially offset beamlets propagate through the third prism to the third surface.
16. The wearable display device of claim 15 , wherein a second side surface of the third prism is parallel to the waveguide and perpendicular to the output surface of the first prism.
17. The wearable display device of claim 13 , wherein the first plurality of spatially offset beamlets enter the third prism perpendicular to a first side surface of the third prism.
18. The wearable display device of claim 13 , wherein the first plurality of spatially offset beamlets is offset across a longitudinal direction of the waveguide, and the two-dimensional array of beamlets is offset along a latitudinal direction of the waveguide.
19. The wearable display device of claim 13 , wherein the first prism and the second prism are configured to receive the collimated incoming light beam and output the first plurality of spatially offset beamlets.
20. The method of claim 7 wherein the first prism and the second prism are configured to convert the collimated incoming light beam into a first plurality of spatially offset beamlets and the third prism and the fourth prism are configured to convert the first plurality of spatially offset beamlets into the two-dimensional array of beamlets.