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 method of forming a color-changing fiber that can be incorporated into fabrics and other woven materials. The color changing fibers include an annular wall and a conductive wire axially extending through the annular wall, a core strand surrounded by the annular wall and extending axially through a central portion of the fiber, and an encapsulated electro-optic medium disposed on a surface of the core strand.

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.

Integrated wavelength selectors are described. The wavelength selector may include silicon nitride ring resonator disposed vertically between a heater and a temperature sensor. The temperature sensor may be formed of silicon in some embodiments. The wavelength selector may be coupled to the output port of a tunable laser, or may be disposed within a laser cavity.

A method for producing a composite pane, includes arranging a functional element in a recess of a thermoplastic frame film, arranging the thermoplastic frame film along with the functional element between a first glass pane and a second glass pane to form a layer stack, and subsequent joining of the layer stack by lamination to form a composite pane. The thermoplastic frame film and the functional element have a different thickness and the different thickness is at least partially compensated by at least one thermoplastic compensating film, whose thickness is less than twice as large as the difference between the thicknesses of the thermoplastic frame film and the functional element such that the maximum offset in the layer stack is less than the difference between the thicknesses of the thermoplastic frame film and the functional element.

A device, such as an electroabsorption modulator, can modulate a light intensity by controllably absorbing a selectable fraction of the light. The device can include a substrate. A waveguide positioned on the substrate can guide light. An active region positioned on the waveguide can receive guided light from the waveguide, absorb a fraction of the received light, and return a complementary fraction of the received light to the waveguide. Such absorption produces heat, mostly at an input portion of the active region. The input portion of the active region can be thermally coupled to the substrate, which can dissipate heat from the input portion, and can help avoid thermal runaway of the device. The active region can be thermally isolated from the substrate away from the input portion, which can maintain a relatively low thermal mass for the active region, and can increase efficiency when heating the active region.

A display device includes imaging unit (101) to generate a captured image, image recognizer (102) to recognize whether or not the captured image contains a reception terminal, light emitter (106) to emit light in accordance with a modulation signal, and transmission controller (103) and light emission controller (105) to control driving of light emitter (106) based on a result recognized by image recognizer (102).

The present disclosure discloses a dimming method for a dimming glass, including: in response to a dimming level selected from a user, obtaining a light transmittance value corresponding to the selected dimming level according to a corresponding relationship between dimming levels and actual light transmittance of the dimming glass; obtaining a dimming voltage value corresponding to the light transmittance value according to a corresponding relationship between the actual light transmittance and dimming voltages of the dimming glass; and adjusting a voltage applied to the dimming glass to the obtained dimming voltage value, wherein the corresponding relationship between the dimming levels and the actual light transmittance of the dimming glass is dividing an adjustable range of the actual light transmittance of the dimming glass to obtain the actual light transmittance corresponding to different dimming levels. The present disclosure improves dimming effect of dimming glass.

Methods, apparatus, and systems for mitigating pinhole defects in optical devices such as electrochromic windows. One method mitigates a pinhole defect in an electrochromic device by identifying the site of the pinhole defect and obscuring the pinhole to make it less visually discernible. In some cases, the pinhole defect may be the result of mitigating a short-related defect.

An apparatus is described for converting light of a light source into electrical energy. The apparatus includes a layered body having flat elements, a photovoltaic cell, a light conducting element, a light-switching element , and a photovoltaic cell arranged on a boundary surface of the layered body. The light-switching element (16) can be set to either transmit or block light, In the case of blocking, the light-switching element couples light into the photovoltaic cell t to convert received light into electric energy.