An irradiation device for an additively manufacturing apparatus may include a working beam generation device configured to provide a working beam, a modulation beam generation device configured to provide a modulation beam, and a solid-state optical modulator that includes a crystalline material that exhibits a change in refractive index in response to photoexcitation of free electrons within the crystalline material. The irradiation device may include a power source coupled to the solid-state optical modulator and configured to introduce free electrons into the crystalline material. The modulation beam may cause photoexcitation of the free electrons within the crystalline material. The photoexcitation of the free electrons within the crystalline material may cause the crystalline material to exhibit a change in refractive index. The working beam, when incident upon the crystalline material, may exhibit a change in one or more parameters, such as a phase shift, attributable at least in part to the change in refractive index exhibited by the crystalline material.

An optical modulator includes: an optical modulation element that is configured to generate two modulated light beams, each of which is modulated by two sets of electrical signals, and that includes a plurality of signal electrodes; a plurality of signal input terminals, each of which inputs an electrical signal; a relay substrate on which a plurality of signal conductor patterns and a plurality of ground conductor patterns are formed, the relay substrate being configured to propagate the two sets of electrical signals by two pairs of the adjacent signal conductor patterns; and a housing, in which the at least two signal conductor patterns including at least one parts mounting part including electrical circuit elements are configured such that first signal propagation directions, which are signal propagation directions at the parts mounting parts, are different from each other.

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.

Apparatus include a photoelastic modulator (PEM) optical element, a controller having a frequency generator configured to produce a frequency signal at a selected frequency based on a clock signal of the controller wherein the controller is configured to produce a PEM driving signal based on the frequency signal, a PEM transducer coupled to the PEM optical element and the controller and configured to drive the PEM with the PEM driving signal, and a detector optically coupled to the PEM optical element and configured to receive a PEM modulated output and to produce a PEM detection signal that includes a PEM modulation signal, wherein the controller is configured to receive the PEM detection signal and to extract the PEM modulation signal from the PEM detection signal using the frequency signal and the clock signal.

A spatial light modulator is provided, including a backplane inside which a drive circuit is disposed, a phase adjustment unit, an electrode, and an electrical connection portion. The phase adjustment unit includes a lower cavity mirror, a cavity layer, and an upper cavity mirror, and the lower cavity mirror is located between the cavity layer and the backplane. The electrode includes a first electrode and a second electrode, and the electrode is located inside or on a surface of the phase adjustment unit, and is located on a side that is of the lower cavity mirror and that faces away from the backplane. The electrical connection portion is electrically connected to the electrode and the drive circuit, to form a drive electric field between the first electrode and the second electrode, and adjust a refractive index of the phase adjustment unit.

An optical system that includes a reconfigurable phase-change material (PCM) layer that includes a plurality of individually controllable pixel areas. Each individually controllable pixel area is variable between a first refractive index and a second refractive index. The PCM layer is configured to pass radiation incident on the PCM layer in accordance with a first mask pattern through the PCM layer in a downstream direction. A PCM controller is configured to control the plurality of individually controllable pixel areas to have respective refractive indices in accordance with the first mask pattern.

A driving circuit is a circuit selectively outputting one of a staircase wave and a square wave from an output terminal, to drive a capacitive load, and includes a first power source supplying a constant voltage VH, a first FET connected between the output terminal and the first power source, a first transformer in which an output side coil is connected to a gate of the first FET, a first input terminal connected to an input side coil of the first transformer via a capacitive element, a second power source supplying a constant voltage VL, a second FET connected between the output terminal and the second power source, a second transformer in which an output side coil is connected to a gate of the second FET, and a second input terminal connected to an input side coil of the second transformer via a capacitive element.

In an optical modulator, a light-receiving element, and an output port are disposed in a substrate. In addition, at least a part of an electrical line, which electrically connects the light-receiving element and the output port to each other, is formed in the substrate. In addition, a plurality of the optical modulation sections are provided. In addition, among a plurality of the light-receiving elements which are provided to the optical modulation sections, at least one light-receiving element is disposed at a position different from positions of the other light-receiving elements in a light wave propagating direction. A plurality of the output ports are disposed in an arrangement in the light wave propagating direction in correspondence with an arrangement of the plurality of the light-receiving elements in the light wave propagating direction.

In an optical modulator, a light-receiving element (3a) that receives a light wave modulated in an optical modulation section (Ma) and a light-receiving element (3b) that receives a light wave modulated in an optical modulation section (Mb) are provided in a substrate. In addition, at least a part of an electrical line (4a) that guides a light-receiving signal output from the light-receiving element (3a) to an outer side of the substrate, and at least apart of an electrical line (4b) that guides a light-receiving signal form the light-receiving element (3b) to an outer side of the substrate are formed in the substrate. In addition, crosstalk suppression means (5), which suppress crosstalk between the electrical line (4a) and the electrical line (4b), is provided between the part of the electrical line (4a) and the part of the electrical line (4b) which are formed in the substrate.

Provided is an electro-optical phase modulation system, including: an electro-optical crystal, a radio frequency circuit and a light source, light incident surface of the electro-optical crystal is in parallel with light exit surface, upper electrode surface thereof is in parallel with lower electrode surface, and an angle between light incident surface and upper electrode surface is Brewster angle; two electrodes of radio frequency circuit are connected to upper and lower electrode surfaces respectively, for transmitting radio frequency signals to upper and lower electrode surfaces, so that an electric filed, direction of which is perpendicular to upper electrode surface, is formed between upper and lower electrode surfaces; light source is located at a side of light incident surface, and incidence angle of beams from light source with respect to light incident surface is Brewster angle. The system is used to reduce residual amplitude modulation, and increase accuracy of phase modulation.