A Pockels cell utilizes high-voltage pulses for a polarization adjustment of electromagnetic radiation passing through the crystal, in particular laser radiation. The polarization adjustment involves applying a sequence of useful voltage pulses (N) to the crystal, each having a useful period duration (TP, N) and a useful pulse width (TN), and induces birefringence of the crystal via electric polarization in the crystal for polarization adjustment of the electromagnetic radiation. A sequence of compensation pulses (K, K1, K2) are applied to the crystal, each having a voltage curve, wherein the sequence is temporally overlaid by the sequence of useful voltage pulses (N) so that the voltage curves of the compensation pulses (K, K1, K2) counteract the inducing of a mechanical vibration in the crystal of the Pockels cell by the useful voltage pulses (N).

The present disclosure provides a display device, including: a light emitting device and a light adjusting layer, the light adjusting layer being on a light emitting side of the light emitting device, and the light emitting device being configured to generate and emit light having a wavelength in a wavelength range of visible light, wherein the light adjusting layer is configured to block light having a wavelength in a partial wavelength range of blue light from passing through when subjected to an external stimulus and allow the light having the wavelength in the partial wavelength range of blue light to pass through when the external stimulus is removed, and the light adjusting layer includes a responsive photonic crystal.

An optical modulator includes an optical modulation element (102) including a plurality of signal electrodes (112a and the like), a plurality of lead pins (116a and the like) for inputting high frequency signals, and a relay substrate (118) in which conductor patterns (202a and the like) that electrically connect the lead pins and the signal electrodes are formed, and at least one of the conductor patterns in the optical modulator is constituted so that at least one resonant frequency of the at least one of the conductor patterns is different from at least one resonant frequency of at least one of the other conductor patterns.

An adjustable aperture for an imager includes a mechanical aperture having an opening for permitting light to pass through the mechanical aperture; and an electro-optic shutter having a hole in at least one linearly polarizing layer such that at least a portion of light incident on the electro-optic shutter can pass through the electro-optic shutter regardless of an operating state of the electro-optic shutter, wherein an aperture size of the adjustable aperture is defined by the mechanical aperture when the electro-optic shutter is controlled for light transmission and by the electro-optic shutter when the electro-optic shutter is controlled for light blocking.

Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with the capability of switching between a modelocked pulse operating mode and an amplification operating mode. The operating modes are carried out through the application of a time-dependent bias voltage, having waveforms as described herein, to an electro-optical device (e.g., a Pockels cell) positioned along the optical axis of the resonator.

A photonic computing system, preferably including an input module, a computation module, and/or control module. The photonic computing system can include one or more optical filter banks, such as in the computation module and/or any other suitable modules. Each optical filter bank preferably includes a plurality of photonic bandgap phase modulators. Each photonic bandgap phase modulator preferably includes a set of photonic crystal segments. The photonic crystal segments can preferably be controlled to transition light propagation between two or more photonic bands.

A photonic computing system, preferably including an input module, a computation module, and/or control module. The photonic computing system can include one or more optical filter banks, such as in the computation module and/or any other suitable modules. Each optical filter bank preferably includes a plurality of photonic bandgap phase modulators. Each photonic bandgap phase modulator preferably includes a set of photonic crystal segments. The photonic crystal segments can preferably be controlled to transition light propagation between two or more photonic bands.

Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with the capability of switching between a modelocked pulse operating mode and an amplification operating mode. The operating modes are carried out through the application of a time-dependent bias voltage, having waveforms as described herein, to an electro-optical device (e.g., a Pockels cell) positioned along the optical axis of the resonator.

Described herein are methods for developing and maintaining pulses that are produced from compact resonant cavities using one or more Q-switches and maintaining the output parameters of these pulses created during repetitive pulsed operation. The deterministic control of the evolution of a Q-switched laser pulse is complicated due to dynamic laser cavity feedback effects and unpredictable environmental inputs. Laser pulse shape control in a compact laser cavity (e.g., length/speed of light<1 ns) is especially difficult because closed loop control becomes impossible due to causality. Because various issues cause laser output of these compact resonator cavities to drift over time, described herein are further methods for automatically maintaining those output parameters.

A control unit of a bias control circuit performs a loop process that fixes a second bias voltage and iterates a process of recording a pair of a first candidate bias voltage and a second candidate bias voltage that are a first bias voltage when optical power of a multi-level QAM signal output by an optical modulator is controlled so that the optical power converges to a value in the vicinity of the maximum value or the minimum value before and after a third bias voltage is increased or decreased by a half-wave voltage while changing the second bias voltage within a predetermined range. The control unit calculates the difference between the first candidate bias voltage and the second candidate bias voltage for each of a plurality of recorded pairs and determines a value between first candidate bias voltage and the second candidate bias voltage of a pair selected on the basis of the calculated difference as the value of the first bias voltage.