An optical device for providing illumination light includes an optical waveguide and a plurality of polarization selective elements. The plurality of polarization selective elements is disposed adjacent to the optical waveguide so that a respective polarization selective element receives light in a first direction, and redirects a first portion of the light in a second direction. A second portion, distinct from the first portion, of the light undergoes total internal reflection, thereby continuing to propagate inside the optical waveguide.

An optical device includes an optical waveguide and a plurality of reflective polarizers. The plurality of reflective polarizers include a first reflective polarizer and a second reflective polarizer disposed inside the optical waveguide so that the first reflective polarizer receives light propagating inside the optical waveguide, redirects a first portion of the light in a first direction, and transmits a second portion of the light in a second direction non-parallel to the first direction. The second reflective polarizer receives the second portion of the light from the first reflective polarizer, redirects a third portion of the light, and transmits a fourth portion of the light. A ratio between the first portion and the second portion of the light has a first value and a ratio between the third portion and the fourth portion of the light has a second value distinct from the first value.

An optical device includes a spatial light modulator and an optical waveguide with a plurality of extraction features. The plurality of extraction features is positioned relative to the optical waveguide so that a respective extraction feature receives light, having propagated within the optical waveguide, in a first direction and directs a first portion of the light in a second direction distinct from the first direction to exit the optical waveguide and illuminate at least a portion of the spatial light modulator. The plurality of extraction features is also positioned relative to the optical waveguide so that a respective extraction feature directs a second portion, distinct from the first portion, of the light to undergo total internal reflection, thereby continuing to propagate within the optical waveguide.

An optical device includes a light source configured to provide illumination light and a waveguide. The waveguide has an input surface, an output surface distinct from and non-parallel to the input surface, and an output coupler. The waveguide is configured to receive, at the input surface, the illumination light provided by the light source and propagate the illumination light via total internal reflection. The waveguide is also configured to redirect, by the output coupler, the illumination light so that the illumination light is output from the output surface for illuminating a spatial light modulator.

An optical coherent transceiver comprising a polarization and phase-diversity coherent receiver and a polarization and phase-diversity modulator on the same substrate interfaced by three grating couplers, on grating coupler coupling in a signal, one grating coupler coupling in a laser signal, and a third grating coupler coupling out a modulated signal.

Provided is an optical circuit element, and more particularly, is an optical circuit element that splits one optical signal into two polarization signals, or couples two polarization signals into one optical signal. The optical circuit element includes a plurality of input couplers to which an optical signal is input, a plurality of output couplers from which an optical signal is output, a first path and a second path configured to connect the input couplers and the second couplers to each other, and at least one wave plate.

Many embodiments in accordance with the invention are directed towards waveguides implementing birefringence control. In some embodiments, the waveguide includes a birefringent grating layer and a birefringence control layer. In further embodiments, the birefringence control layer is compact and efficient. Such structures can be utilized for various applications, including but not limited to: compensating for polarization related losses in holographic waveguides; providing three-dimensional LC director alignment in waveguides based on Bragg gratings; and spatially varying angular/spectral bandwidth for homogenizing the output from a waveguide. In some embodiments, a polarization-maintaining, wide-angle, and high-reflection waveguide cladding with polarization compensation is implemented for grating birefringence. In several embodiments, a thin polarization control layer is implemented for providing either quarter wave or half wave retardation.

An optical waveguide device for use in a head up display. The waveguide device provides pupil expansion in two dimensions. The waveguide device comprise a primary waveguide and a secondary waveguide, the secondary waveguide being positioned on a face of the primary waveguide. The secondary waveguide has a diffraction grating on a face opposite to the face which contacts the primary waveguide. The diffraction grating diffracts light into more than diffraction order. Rays diffracted into a non-zero order are trapped in the secondary waveguide by total internal reflection.

A waveguide display comprises: a waveguide supporting a single grating layer; a source of data-modulated light; a first input coupler for directing a first spectral band of light from the source into a first waveguide pupil; a second input coupler for directing a second spectral band of light from the source into a second waveguide pupil; an output coupler comprising multiplexed first and second gratings, at least one fold grating for directing the first spectral band along a first path from the first pupil to the output coupler and providing a first beam expansion; at least one fold grating for directing the second spectral band along a second path from the second pupil to the output coupler and providing a first beam expansion. The first multiplexed grating directing the first spectral band out of the waveguide in a first direction with beam expansion orthogonal to the first beam expansion. The second multiplexed grating directing the second spectral band out of the waveguide in the first direction with beam expansion orthogonal to the first beam expansion.

In a general aspect, optical beams are manipulated. In some cases, an optical device includes an inlet to receive a first beam, and one or more prism pairs. Each prism pair includes one or more birefringent gradients configured to transform the first beam into a second beam. The second beam is associated with a lattice of cells, where each cell includes a first portion and a second portion. The first portion is associated with a first orbital angular momentum (OAM) mode and a first polarization, and the second portion is associated with a second OAM mode and a second polarization.