A light modulation element that can vary between a bright transparent mode and a dark scattering mode is provided. The light modulation element has a first light modulation layer and a second light modulation layer comprising nematic liquid crystals and a dichroic dye in a scattering mode when a voltage is applied. The first light modulation layer and the second light modulation layer are disposed to overlap each other. The light modulation element has an improved contrast ratio and haze-variable characteristics, without precipitation of dichroic dyes and an increase in power consumption.

The present disclosure provides an optical circulator. The optical circulator includes a first integrated module, a second integrated module and a third integrated module which are sequentially connected from front to rear. The first integrated module includes a mating shell, an optical fiber ferrule received in the mating shell and a first birefringence crystal attached to a rear surface of the optical fiber ferrule; the second integrated module comprises a first tube fixed behind the mating shell, a magnetic ring received in the first tube, a Wollaston prism fixed in the magnetic ring, two Faraday rotators respectively provided to both sides of the Wollaston prism, and two collimating lenses respectively provided to both sides of the two Faraday rotators. The third integrated module includes a second tube fixed behind the first tube, a dual fiber pigtail received in the second tube, and a second birefringence crystal attached to a front surface of the dual fiber pigtail. The above-mentioned optical circulator is small in volume and convenient to manufacture.

A display device includes a waveguide, an array of tunable retarders in contact with the waveguide, and a polarization selective optical element. A respective tunable retarder of the array of tunable retarders receives light from the waveguide. The respective tunable retarder has a first state, which causes the respective tunable retarder to direct light having a first polarization in a first direction and a second state, which causes the respective tunable retarder to direct light having a second polarization that is distinct from the second polarization in the first direction. The polarization selective optical element is located adjacent to the array of tunable retarders so that the light having the second polarization propagates from the polarization selective optical element in a second direction and the light having the second polarization propagates from the polarization selective optical element in a third direction distinct from the second direction.

Systems and methods for tracking the position of a head-mounted display (HMD) system component. The HMD component may carry a plurality of angle sensitive detectors that are able to detect the angle of light emitted from a light source. The HMD component may include one or more scatter detectors that detect whether light has been scattered or reflected, so such light can be ignored. Control circuitry causes light sources to emit light according a specified pattern, and receives sensor data from the plurality of angle sensitive detectors. The processor may process the sensor data and scatter detector data, for example using machine learning or other techniques, to track a position of the HMD component. An angle sensitive detector may include a spatially-varying polarizer having a position-varying polarizing pattern and one or more polarizer layers that together are operative to detect the angle of impinging light.

A polarization scrambler using a retardance element (RE) is disclosed. The polarization scrambler may include an optical fiber input to transmit an optical signal, and a beam expander to receive and expand the optical signal to create an expanded optical signal. The polarization scrambler may include a retardance element (RE) to cause a polarization scrambling effect on the expanded optical signal and to create a scrambled expanded optical signal. The polarization scrambler may include a beam reducer to receive and reduce the scrambled expanded optical signal to create a scrambled optical signal. The polarization to scrambler may include an optical fiber output to receive scrambled optical signal. The optical fiber output may transmit the scrambled optical signal to one or more downstream optical components.

A switchable polarizer includes a transparent layer and switchable material layer. The switchable material layer includes strips of a switchable material that are arranged to polarize incident light propagating through the transparent layer when the switchable material is heated to a threshold switching temperature. The incident light propagating through the transparent layer is unpolarized by the strips of the switchable material when the switchable material is below the threshold switching temperature.

A high-power electro-optic modulator (EOM) is formed to use specialized electrodes of a material selected to have a CTE that matches the CTE of the modulator's crystal. Providing CTE matching reduces the presence of stress-induced birefringence, which is known to cause unwanted modulation of the propagating optical signal. The specialized electrodes are preferably formed of a CuW metal matrix composite having a W/Cu ratio selected to create the matching CTE value. Advantageously, the CuW-based electrodes also exhibit a thermal conductivity about an order of magnitude greater than conventional electrode material (brass, Kovar) and thus provide additional thermal stability to the EOM's performance.

A freeform varifocal optical assembly includes at least three optical modules including a first plurality of polarization sensitive optical elements including Pancharatnam-Berry phase (PBP) lenses, polarization sensitive hologram (PSH) lenses, metamaterials, or combinations thereof. The plurality of polarization sensitive optical elements of each optical module include a property associated with a Zernike polynomial. Each of the first and the three optical modules are configurable between a plurality of optical powers. The freeform varifocal optical assembly is configurable to output a predetermined wavefront in response to an input wavefront.

Provided is a magneto-optic element that enables easy size reduction of an optical isolator. A magneto-optic element is formed of two or more magnetic members joined together.

A grating emitter method and system for modulating the polarization of an optical beam, such as one for transmission through free-space or use in an atomic clock.