G02F2203/50

Transflective, PCM-based display device

The invention is notably directed to a transflective display device. The device comprises a set of pixels, wherein each of the pixels comprises a portion of bi-stable, phase change material, hereafter a PCM portion, having at least two reversibly switchable states, in which it has two different values of refractive index and/or optical absorption. The device further comprises one or more spacers, optically transmissive, and extending under PCM portions of the set of pixels. One or more reflectors extend under the one or more spacers. An energization structure is in thermal or electrical communication with the PCM portions, via the one or more spacers. Moreover, a display controller is configured to selectively energize, via the energization structure, PCM portions of the pixels, so as to reversibly switch a state of a PCM portion of any of the pixels from one of its reversibly switchable states to the other. A backlight unit is furthermore configured, in the device, to allow illumination of the PCM portions through the one or more spacers. The backlight unit is controlled by a backlight unit controller, which is configured for modulating one or more physical properties of light emitted from the backlight unit. The invention is further directed to related devices and methods of operation.

Optical synapse

An integrated optical circuit for an optical neural network is provided. The integrated optical circuit is configured to process a phase-encoded optical input signal and to provide a phase-encoded output signal depending on the phase-encoded optical input signal. The phase-encoded output signal emulates a synapse functionality with respect to the phase-encoded optical input signal. A related method and a related design structure are further provided.

OPTICAL MODULATION DEVICE AND PHASE MODULATION METHOD USING THE SAME
20220382117 · 2022-12-01 ·

Disclosed are an optical modulation device and a phase modulation method using the same. The optical modulation device includes a reflection plate, an insulating film over the reflection plate, dielectric patterns aligned on the insulating film in a first direction and extended in parallel in a second direction intersecting the first direction, and first and second graphene patterns provided between the dielectric patterns and alternately aligned in the first direction. The dielectric patterns and the first and second graphene patterns fully cover the top of the insulating film. Two dielectric patterns adjacent to each other in the first direction with one of the first graphene patterns interposed therebetween form one dielectric pattern pair. The dielectric pattern pair is provided in plural. The dielectric pattern pairs are isolated from each other in the first direction with one of the second graphene patterns interposed therebetween. A width of each of the first graphene patterns in the first direction is different from a width of each of the second graphene patterns in the first direction.

Silicon thermal-optic phase shifter with improved optical performance

A thermo-optic phase shifter comprises an optical waveguide comprising a P-type region comprising a first contact, an N-type region comprising a second contact, and a waveguide region disposed between the P-type region and the N-type region and having a raised portion. The thermo-optic phase shifter further comprises one or more heating elements. The one or more heating elements include one or more discrete resistive heating elements or the P-type and N-type regions driven as resistive heating elements.

OPTICAL PHASE CONTROL ELEMENTS BASED ON PANCHARATNAM PHASE

Optical phase control elements are based on the Pancharatnam phase. Tunable liquid crystal devices containing the optical phase control elements may include a liquid crystal cell between a pair of substrates, a first plurality of electrodes, and a second plurality of electrodes. Each individual phase control element is defined by one electrode from the first plurality and one electrode from the second plurality.

Quantum Enhanced Optical Modulator or Sensor

In an integrated optical device, squeezed light is used internally to effectively increase an optical modulation effect. One exemplary device operates by squeezing the light at the input, then sending it through an electro-optic stage where its phase picks up the signal of interest, and finally anti-squeezing it to obtain a displaced coherent state. Thus the displacement is amplified by the level of squeezing that is achieved inside the device and it is thereby less sensitive to loss. Since this device behaves simply as an electro-optic modulator, albeit one with an exponentially enhanced sensitivity, no extra considerations are needed to integrate the modulator into a system. Such devices can be operated as modulators or as sensors, and can make use of optical phase shift effects other than the electro-optic effect.

Optical device for forming a distribution of a three-dimensional light field
11506917 · 2022-11-22 · ·

An optical device for forming a distribution of a three-dimensional light field comprises: an array of individually addressable unit cells; each unit cell in the array of unit cells comprising a stack including: at least one electrode; and a resonance defining layer, comprising at least a phase change material, PCM, layer, wherein the resonance defining layer is patterned to define a geometric structure dimensioned for defining a wavelength-dependent in-plane resonance of an electromagnetic wave; wherein the at least one electrode causes a phase change of the phase change material based on receiving a control signal to alter a wavelength-dependency of resonance in the resonance defining layer for controlling the optical property of the unit cell; wherein unit cells in the array of unit cells are separated such that the PCM layer of a unit cell is separated from the PCM layer in an adjacent unit cell.

Method and apparatus for bias control with a large dynamic range for Mach-Zehnder modulators

Improved dither detection, measurement, and voltage bias adjustments for an electro-optical modulator are described. The electro-optical modulator generally includes RF electrodes and phase heaters interfaced with semi-conductor waveguides on the arms of Mach-Zehnder interferometers, where a processor is connected to output a bias tuning voltage to the electro-optical modulator for controlling optical modulation. A variable gain amplifier (VGA) can be configured with AC coupling connected to receive a signal from a transimpediance amplifier (TIA) that is configured to amply a photodetector signal from an optical tap that is used to measure an optical signal with a dither signal. The analog to digital converter (ADC) can be connected to receive output from the VGA. The processor can be connected to receive the signal from the ADC and to output the bias tuning voltage based on evaluation of the signal from the tap.

Optical Phase Shifter Device

An optical phase shifter may include a waveguide core that has a top surface, and a semiconductor contact that is laterally displaced relative to the waveguide core and is electrically connected to the waveguide core. A top surface of the semiconductor contact is above the top surface of the waveguide core. The waveguide core may include a p-type core region and an n-type core region. A p-type semiconductor region may be in physical contact with the n-type core region of the waveguide core, and an n-type semiconductor region may be in physical contact with the p-type core region of the waveguide core. A phase shifter region and a light-emitting region may be disposed at different depth levels, and the light-emitting region may emit light from a phase shifter region that is in a position adjacent to the light-emitting region.

Modular three-dimensional optical sensing system
11585899 · 2023-02-21 · ·

Examples of a three-dimensional (3D) optical sensing system for a vehicle include a modular architecture. Light can be transmitted to an optical signal processing module, which can include a photonic integrated circuit (PIC) that can create one or more signals with tailored amplitude, phase, and spectral characteristics. The plurality of optical signals processed by the optical signal processing module can be sent to beam steering units distributed around the vehicle. The steering units can direct a plurality of optical beams towards targets. The return optical signal can be detected by a receiver PIC including an array of sensors and using a direct intensity detection technique or a coherent detection technique. The return optical signal can be converted into an electrical signal by the array of sensors, which can then be processed by the electronic signal processing unit, and information about the location and speed of the targets can be quantified.