Spatially separated exit pupils in a head mounted display
Disclosed herein are devices and methods to provide multiple eyeboxes from multiple input pupils. In particular, a projection system can direct light from multiple input pupils to a holographic optical element. The light of each of the input pupils having light beams of different wavelengths. The holographic optical element reflects at least part of the light of the multiple input pupils to form an array of exit pupils.
1. A method comprising:
projecting light from a plurality of entrance pupils, each of the plurality of entrance pupils comprising a first light beam having a first wavelength, a second light beam having a second wavelength, and a third light beam having a third wavelength, and wherein the first wavelength is different from the second wavelength and the first and second wavelengths are different from the third wavelength; and
reflecting at a holographic optical element, at least a portion of the light to a plurality of exit pupils, wherein the plurality of exit pupils comprise a first set of exit pupils corresponding to the first light beam having the first wavelength, a second set of exit pupils corresponding to the second light beam having the second wavelength, and a third set of exit pupils corresponding to the third light beam having the third wavelength.
2. The method of claim 1 , at least one of the plurality of entrance pupils spatially separated from at least one other of the plurality of entrance pupils in an out of plane direction of the holographic optical element.
3. The method of claim 1 , wherein the plurality of exit pupils comprises a spatially separated exit pupil for each light beam of the plurality of entrance pupils having a different wavelength.
4. The method of claim 1 , comprising:
emitting the plurality of light beams from one or more light sources; and
directing the plurality of light beams to the holographic optical element from the plurality of entrance pupils by at least one mirror.
5. The method of claim 4 , wherein the one or more light sources comprises a plurality of light sources, each of the plurality of light sources to emit one of the plurality of light beams.
6. The method of claim 5 , comprising:
receiving, at an optical element, light projected by the mirror; and
directing, at the optical element, the projected light to the holographic optical element from the plurality of entrance pupils.