Optical apparatus (20) includes a transparent envelope (26) configured to be mounted in a spectacle frame. An electro-optical layer (46) is contained within the envelope, with an array of transparent excitation electrodes (50) disposed over a first surface of the transparent envelope. A transparent common electrode (52) is disposed over a second surface of the transparent envelope, opposite the first surface, and is electrically separated into a central region defining an active area (24) of the electro-optical layer and a peripheral region, which at least partially surrounds the central region. Control circuitry (72, 82, 92) holds the central region of the transparent common electrode at a predefined common voltage while allowing the peripheral region to float electrically, and to apply control voltage waveforms to the excitation electrodes, relative to the common voltage, so as to generate a specified phase modulation profile in the active area of the electro-optical layer.

An electro-holographic light field generator device is disclosed. The light field generator device has an optical substrate with a waveguide face and an exit face. One or more surface acoustic wave (SAW) optical modulator devices are included within each light field generator device. The SAW devices each include a light input, a waveguide, and a SAW transducer, all configured for guided mode confinement of input light within the waveguide. A leaky mode deflection of a portion of the waveguided light, or diffractive light, impinges upon the exit face. Multiple output optics at the exit face are configured for developing from each of the output optics a radiated exit light from the diffracted light for at least one of the waveguides. An RF controller is configured to control the SAW devices to develop the radiated exit light as a three-dimensional output light field with horizontal parallax and compatible with observer vertical motion.

A Pancharatnam Berry Phase (PBP) color corrected structure is presented that comprises a plurality of switchable gratings and a plurality of PBP active elements. Each switchable grating has an inactive mode when reflects light of a specific color channel, of a set of color channels, and transmits light of other color channels in the set of color channels, wherein the specific color channel is different for each of the plurality of switchable gratings, and to have an active mode to transmit light that is inclusive of the set of color channels. The PBP active elements receive light output from at least one of the plurality of switchable gratings. Each of the PBP active elements is configured to adjust light of a different color channel of the set of color channels by a same amount to output light corrected for chromatic aberration for the set of color channels.

A typical liquid crystal lens includes liquid crystal sandwiched between transparent substrates, which are patterned with ring electrodes. Applying a voltage across the electrodes causes the liquid crystal molecules to rotate, changing their apparent refractive index and the lens's focal length. The ring electrodes are separated by gaps and get narrower toward the lens's periphery. If the ring electrodes are too narrower, their cannot switch the liquid crystal well. To address this problem, an inventive liquid crystal lens includes a substrate with a stepped surface that defines concentric liquid crystal regions with thicknesses that increase with lens radius. Each region is switched by a different set of ring electrodes, which may be on, under, or opposite the stepped surface. Within each region, the ring electrodes get narrower farther from the lens's center. But the ring electrodes' widths also increase with liquid crystal thickness, offsetting the decrease in width that degrades lens performance.

An optical device includes a liquid crystal layer having a first plurality of liquid crystal molecules arranged in a first pattern and a second plurality of liquid crystal molecules arranged in a second pattern. The first and the second pattern are separated from each other by a distance of about 20 nm and about 100 nm along a longitudinal or a transverse axis of the liquid crystal layer. The first and the second plurality of liquid crystal molecules are configured as first and second grating structures that can redirect light of visible or infrared wavelengths.

An optical device includes a liquid crystal layer having a first plurality of liquid crystal molecules arranged in a first pattern and a second plurality of liquid crystal molecules arranged in a second pattern. The first and the second pattern are separated from each other by a distance of about 20 nm to about 100 nm along a longitudinal or a transverse axis of the liquid crystal layer. The first and the second plurality of liquid crystal molecules are configured as first and second grating structures that can redirect light of visible or infrared wavelengths.

According to one example, an optical element assembly includes a transparent rod, a mirror and a light emitting element. The rod transmits light of first wavelength region made incident on a first end of the rod and emits the light of the first wavelength region from a second end of the rod. The rod absorbs light of a second wavelength region falling out of the first wavelength region. The mirror is disposed on a side of the first end. The mirror transmits one of the light of the first and second wavelength regions, reflects the other. The light of the first and second wavelength regions are made incident on the first end of the rod. The light emitting element emits light of the second wavelength region made incident on the first end of the rod through the mirror.

An optical device, comprising: —a first electrode layer; —a second electrode layer provided at a distance from the first electrode layer; —the first and second electrode layer being light transmitting; wherein the optical device further comprises, in between the first and the second electrode layers: o a diffractive optical element adjacent to the first electrode layer and comprising at least one sloped surface; and o a liquid crystalline material filling a space between the sloped surface and the second electrode layer; the liquid crystalline material having a pretilt that compensates for a slope angle of the at least one sloped surface.

An eye tracker comprises a light source; a detector; and first and second waveguides. The first waveguide comprises an input coupler for coupling source light into a waveguide path and a first grating for coupling light out of the waveguide path onto an eye. The second waveguide comprises a second grating for coupling light reflected from the eye into a waveguide path and an output coupler for coupling light out of the waveguide path onto the detector. The second grating is optically configured for imaging the eye onto the detector.

A typical liquid crystal lens includes liquid crystal sandwiched between transparent substrates, which are patterned with ring electrodes. Applying a voltage across the electrodes causes the liquid crystal molecules to rotate, changing their apparent refractive index and the lens's focal length. The ring electrodes are separated by gaps and get narrower toward the lens's periphery. If the ring electrodes are too narrower, their cannot switch the liquid crystal well. To address this problem, an inventive liquid crystal lens includes a substrate with a stepped surface that defines concentric liquid crystal regions with thicknesses that increase with lens radius. Each region is switched by a different set of ring electrodes, which may be on, under, or opposite the stepped surface. Within each region, the ring electrodes get narrower farther from the lens's center. But the ring electrodes' widths also increase with liquid crystal thickness, offsetting the decrease in width that degrades lens performance.