Polarization-multiplexed optics for head-mounted display systems
The present disclosure is related generally to techniques for improving the performance and efficiency of display systems, such as laser scan beam display systems or other types of display systems (e.g., micro-displays) of an HMD system or other device. Display systems of the present disclosure may utilize polarization multiplexing that allow for improved optimization of diffraction optics. In at least some implementations, a display system may selectively polarize light dependent on wavelength (e.g., color) or field of view. An optical combiner may include polarization sensitive diffractive optical elements that are each optimized for a subset of colors or portions of an overall field of view, thereby providing improved correction optics for a display system.
1. A head-mounted display system, comprising:
a support structure; and
a display system coupled to the support structure, the display system comprising:
a display light source;
a selective polarizer optic operative to receive light from the display light source, and to output light of a first color in a first polarization state and light of a second color in a second polarization state, the second polarization state orthogonal to the first polarization state; and
an optical combiner positioned to receive light from the selective polarizer optic and to provide images to an eye of a viewer, the optical combiner comprising:
a first polarization sensitive diffractive optical element (PSDOE) that includes a first diffraction pattern that diffracts light of the first polarization state and passes light of the second polarization state without diffraction, the first diffractive pattern providing optimized correction for the first color; and
a second PSDOE that includes a second diffraction pattern that diffracts light of the second polarization state and passes light of the first polarization state without diffraction, the second diffractive pattern providing optimized correction for the second color.
2. The head-mounted display system of claim 1 wherein each of the selective polarizer optic, the first PSDOE, and the second PSDOE comprises a multi-twist retarder.
3. The head-mounted display system of claim 1 wherein at least one of the selective polarizer optic, the first PSDOE, and the second PSDOE comprise a multi-twist retarder.
4. The head-mounted display system of claim 1 wherein at least one of the selective polarizer optic, the first PSDOE, and the second PSDOE comprise liquid crystal material.
5. The head-mounted display system of claim 1 wherein a selective polarizer optic is operative to output light of a third color in the second polarization state, and the second diffractive pattern provides optimized correction for the second color and the third color.
6. The head-mounted display system of claim 5 wherein the first color is red and the second and third colors are green and blue, respectively.
7. The head-mounted display system of claim 1 wherein the first color is red, and the second color is green or blue.
8. The head-mounted display system of claim 1 wherein the optical combiner comprises an in-coupler and an out-coupler.
9. The head-mounted display system of claim 1 wherein the support structure comprises an eyeglasses lens.
10. The head-mounted display system of claim 1 wherein the display light source comprises a laser scan beam system or a micro-display.