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.

A method of controlling a display device is a method for controlling a display device including a light modulation sheet switchable between a transparent state and an opaque state. When an operation to turn on the display device is obtained, a PWM waveform for generating an alternating voltage based on a direct voltage is output, the alternating voltage having a duty cycle of 50% at a phase of 0 degrees or 180 degrees, the alternating voltage is generated from the direct voltage, based on the PWM waveform output, and the alternating voltage generated is output to the light modulation sheet.

A laser irradiation apparatus including a laser light source includes a first detection unit and a second detection unit configured to detect luminance of a substrate irradiated with laser light from the laser light source, and a control unit configured to perform control related to laser light emitted from the laser light source, in which the control unit specifies an energy density of laser light based on luminance detected by the first detection unit, specifies reference luminance based on a specified energy density and luminance detected by the second detection unit, and changes an energy density of laser light according to the reference luminance and luminance detected by the second detection unit.

An electro-optical modulator is provided. The modulator comprises a first and a second optical waveguide, at least one first capacitance, via which a voltage can be applied to a light-guiding region of the first optical waveguide, at least one second capacitance, via which a voltage can be applied to a light-guiding region of the second optical waveguide, an electrically conductive region, via which the first and second capacitances are electrically connected to one another, and a feed line to the electrically conductive region, via which feed line a DC voltage can be applied to the electrically conductive region, wherein the feed line is constituted such that it represents an electrical resistance connected in parallel with the second capacitance, and a compensation resistance connected in parallel with the first capacitance and serving for reducing transients in a voltage profile on the first and second capacitances during the operation of the modulator.

A laser irradiation method of irradiating, with a pulse laser beam, an irradiation object in which an impurity source film is formed on a semiconductor substrate includes: reading fluence per pulse of the pulse laser beam with which a rectangular irradiation region set on the irradiation object is irradiated and the number of irradiation pulses the irradiation region is irradiated, the fluence being equal to or larger than a threshold at or beyond which ablation potentially occurs to the impurity source film when the irradiation object is irradiated with pulses of the pulse laser beam in the irradiation pulse number and smaller than a threshold at or beyond which damage potentially occurs to the surface of the semiconductor substrate; calculating a scanning speed Vdx; and moving the irradiation object at the scanning speed Vdx relative to the irradiation region while irradiating the irradiation region with the pulse laser beam at the repetition frequency f.

A heads-up display may comprise a viewing screen having a reflective surface; a housing defining an opening; a display element disposed within the housing and comprising an integral linear polarizer configured to polarize light in a first direction; and a first linear polarizer disposed between the display element and the viewing screen covering the opening defined by the housing configured to polarize light in the first direction. The display element may be capable of causing images to be displayed on the viewing screen.

An optical device stack includes at least one of a photodetector or an optical emitter and a metasurface. The metasurface is disposed over a light-receiving surface of the photodetector or a light emission surface of the optical emitter. The metasurface includes a first conductive layer having an electrically-tunable optical property and an array of conductive nanostructures disposed on a first side of the first conductive layer. A second conductive layer is disposed on a second side of the first conductive layer. An electrical insulator is disposed between the first conductive layer and the second conductive layer. A change in an electrical bias between the metasurface and the second conductive layer, from a first electrical bias to a second electrical bias, tunes the electrically-tunable optical property from a first state to a second state, and changes an electrically-tunable optical filtering property of the metasurface.

A multi-layer device comprising a first substrate, a first electrically conductive layer and a first current modulating structure on a surface thereof, the first current modulating structure comprising a composite of a resistive material and a patterned insulating material, the first current modulating structure having a cross-layer resistance to the flow of electrical current through the first current modulating structure that varies as a function of position.

In a system for converting digital data into a modulated optical signal, an electrically controllable device, including a modulator having one or more actuating electrodes, provides an analog-modulated optical signal that is modulated in response to output data bits of a digital-to-digital mapping. A digital-to-digital conversion provides the mapping of input data words to the output data bits. The mapping enables adjustments to correct for non-linearities and other undesirable characteristics, thereby improving signal quality.

An integrated device comprising at least one photovoltaic element, at least one light modulating element, at least one light reflecting element and one or more electrical conductors coupled to the photovoltaic element and the light modulating element. An interrogating light beam can be pointed at the integrated device, and a modulated light beam is reflected back by the device in the direction of the interrogating light beam with the reflected light beam containing information/data being modulated by the device onto the reflected light beam.