Abstract: An optical device includes at least three optical ports. An optical arrangement arranges an optical beam received from any of the optical ports into a first polarization state. A dispersion element spatially separates the optical beam into a plurality of wavelength components. An optical power element converges each wavelength component in at least one direction. A programmable optical phase modulator steers the wavelength components through the optical arrangement, the dispersion element and the focusing element to a selected optical output. The programmable optical phase modulator includes an active area that performs the steering and a non-active area surrounding the active area. A polarizing arrangement located in an optical path between at least one of the optical ports and at least a portion of the non-active area of the programmable optical phase modulator is configured to arrange optical energy into a second polarization state orthogonal to the first polarization state.

Abstract: Variable repetition rate and wavelength optical pulse source, comprising a fixed or variable repetition rate source of supercontinuum pulses; a wavelength tunable optical bandpass filter to filter the supercontinuum pulses at two or more wavelengths, wherein said source of supercontinuum pulses and said wavelength tunable optical bandpass filter are configured such that the optical pulse source can provide variable repetition rate and variable wavelength optical pulses including a series of repetition rates with selected wavelength-varying pulse trains.

Abstract: A light irradiation device is an apparatus for irradiating an irradiation object, and includes a light source outputting readout light L1, a spatial light modulator modulating the readout light L1 in phase to output modulated light L2, and a both-sided telecentric optical system including a first lens optically coupled to a phase modulation plane of the spatial light modulator and a second lens optically coupled between the first lens and the irradiation object, and optically coupling the phase modulation plane and the irradiation object. An optical distance between the phase modulation plane and the first lens is substantially equal to a focal length of the first lens. The spatial light modulator displays a Fresnel type kinoform on the phase modulation plane.

Abstract: An image display apparatus according to an embodiment of the present technology includes a light source section, one or more reflection type light modulators, an optical system, and a light shielding plate. The light source section includes at least one or more laser light sources. The one or more reflection type light modulators modulate and reflect incident light. The optical system splits light from the light source section into a plurality of split light beams, superimposes the plurality of split light beams on the one or more reflection type light modulators, and causes them to enter. The light shielding plate is provided in the optical system and includes an aperture provided on a path of each of the plurality of split light beams and a light shielding portion that shields reflection light from the reflection type light modulator to the light source section.

Abstract: Method and devices of controlling wavelengths in two-channel DEMUX/MUX in silicon photonics are provided. The two-channel DEMUX/MUX includes a waveguide-based delay-line-interferometer at least in receiver portion of a two-channel transceiver for DWDM optical transmission loop and is configured to split a light wave with combined two-wavelengths into one light wave with locked one channel wavelength and another light wave with locked another channel wavelength. The waveguide-based delayed-line interferometer (DLI) is characterized by a free-spectral-range configured to be equal to twice of channel spacing. The method includes tuning heater of DLI in receiver of each two-channel transceiver by using either low-frequency dither signals added on MZMs associated with respective two channels as feedback signal or one DFB laser wavelength tapped from an input of transmitter portion at one channel before or after the MZMs as a direct wavelength reference to feed into an output of receiver portion at another channel.

Abstract: A beam shaping device includes a first phase modulation unit including a phase-modulation type SLM, and displaying a first phase pattern for modulating a phase of input light, a second phase modulation unit including a phase-modulation type SLM, being optically coupled to the first phase modulation unit, and displaying a second phase pattern for further modulating a phase of light phase-modulated by the first phase modulation unit, and a control unit providing the first and second phase patterns to the first and second phase modulation units, respectively. The first and second phase patterns are phase patterns for approximating an intensity distribution and a phase distribution of light output from the second phase modulation unit, to predetermined distributions.

Abstract: A transmitter comprising a plurality of modulator and multiplexer (Mod-MUX) units, each Mod-MUX unit operating at an optical wavelength different from the other Mod-MUX units. The transmitter can additional include in each Mod-MUX unit two optical taps and three photodetectors that are configured to allow the respective Mod-MUX unit to be tuned to achieve thermal stabilization and achieve effective modulation and WDM operation across a range of temperatures. The Mod-MUX transmitter avoids the use of a frequency comb. The Mod-MUX transmitter avoids cross-modulation between different modulators for different laser signals.

Abstract: A resonator is described. The resonator includes multiple electrodes. The resonator also includes a composite piezoelectric material. The composite piezoelectric material includes at least one layer of a first piezoelectric material and at least one layer of a second piezoelectric material. At least one electrode is coupled to a bottom of the composite piezoelectric material. At least one electrode is coupled to a top of the composite piezoelectric material.

Abstract: An optical device includes an optical port array, a first walk-off crystal, a first half-wave plate, a second walk-off crystal and a segmented half-wave plate. The optical port array has a first and second plurality of ports for receiving optical beams. The first walk-off crystal spatially separates the beams into first and second portions that are in first and second orthogonal polarization states, respectively. The first portions are walked-off by the first walk-off crystal and the second portions pass therethrough without being walked-off. The first half-wave plate rotates the polarization state of the first and second portions of the optical beams. The second walk-off crystal is oriented in an opposite direction from the first walk-off crystal such that the second portions are walked-off by the second walk-off crystal and the first portions pass therethrough without being walked-off. The segmented half-wave plate receives the first or second portions of the beams.

Abstract: A spatial light modulation device includes a phase-modulation type spatial light modulator, a temperature sensor detecting a temperature of the spatial light modulator, and a control unit providing a drive signal to the spatial light modulator. The control unit has a storage unit. The storage unit stores N correction patterns created so as to correspond to N (N is an integer not less than 2) temperature values of the spatial light modulator in order to correct phase distortion of the spatial light modulator. The control unit selects one correction pattern according to a temperature value of the spatial light modulator, and generates the drive signal based on a phase pattern created by adding the one correction pattern to a desired phase pattern. Thereby, it becomes possible to suppress phase distortion according to a temperature change while suppressing a delay in operation.

Abstract: A piezo electrical component has a stack of piezo electrical layers arranged over each other and electrode layers arranged therebetween. The stack has at least one first piezo electrical layer having a first piezo electrical charge constant and, directly adjacent thereto, at least one second piezo electrical layer having a second piezo electrical charge constant. The piezo electrical charge constant describes an expansion of the piezo electrical layer perpendicular to an electrical field at a voltage 6 applied to the electrode layers. The first piezo electrical charge constant is different from the second piezo electrical charge constant.

Abstract: A micro-projection system for projecting light on a projection surface, comprising: —at least one coherent light source (101); —optical elements (102, 108, 109) in the optical path between said coherent light source and said projection surface; —said optical elements including at least one reflective member (102) actuated by a drive signal for deviating light from said light source so as to scan a projected image onto said projecting surface; —said optical elements including at least one vibrating element (102) actuated by a vibrating signal so as to reduce speckle onto said projecting surface. The corresponding method for reducing speckle is also provided.

Abstract: A system and method for decreasing the optical pathway length, varying brightness output quality, and stabilizing beams along the non-beam combining dimension in a WBC system.

Abstract: An optical waveguide device module is provided, wherein a control electrode includes a signal electrode and ground electrodes disposed to sandwich the signal electrode, a connection substrate is provided with a signal line and ground lines disposed to sandwich the signal line, the distance W1 between the ground electrodes in the input end or the output end of the control electrode is larger than the distance W2 between the ground lines on the optical waveguide device side of the connection substrate, the control electrode has a portion of which the distance between the ground electrodes is smaller than the distance W2 in a portion away from the input end or the output end thereof, and interconnections of which the distance W between ground interconnections connecting the optical waveguide device and the connection substrate is at least smaller than the distance W1.

Abstract: Electrooptical cell, including, on a substrate (1), a layer of ferroelectric massive material (4), with an electrode (2) forming an earth plane, provided between the substrate (1) and the ferroelectric layer (4), another electrode (5), narrow, mounted opposite the first above the ferroelectric layer and grooves (6) made in the ferroelectric layer, on either side of the upper electrode (5).

Abstract: On/off digital drive signals are used to create arbitrary spatial and temporal ribbon movement patterns in MEMS ribbon arrays.

Abstract: An aberration correction device (3) corrects wave front aberration arising in an optical system that includes an object lens (4) disposed in an optical path for light beams output by a coherent light source (1). The aberration correction device (3) has a symmetrical aberration correction element (3a) that corrects symmetrical aberrations, which are the wave front aberrations that are symmetrical with respect to the optical axis among the wave front aberrations generated in the optical path, and an asymmetrical aberration correction element (3b) that corrects asymmetrical aberrations, which are wave front aberrations that are asymmetrical with respect to the optical axis, generated in light beams incident obliquely on the object lens (4).

Abstract: A wavelength selective switch for selectively switching optical wavelength components of an optical signal uses both LCoS and MEMs switching technologies to improve device performance. Specific performance improvements may include more ports, better spectral performance and isolation, improved dynamic crosstalk, more flexible attenuation options, integrated channel monitoring and compressed switch heights.

Abstract: In an optical modulation device, a first drive signal and a first bias signal are applied to a phase modulation unit, a second drive signal and a second bias signal are applied to a phase modulation unit, and a third bias signal is applied to a ?/2 phase shift unit. A control unit adjusts the third bias signal in a first adjustment period, adjusts the first drive signal and the first bias signal in a second adjustment period next to the first adjustment period, and adjusts the second drive signal and the second bias signal in a third adjustment period next to the second adjustment period. The control unit starts the second adjustment period before a gap between the current value of an adjustment reference signal and a target value is filled, and starts the third adjustment period before a gap in the second adjustment period is filled.

Abstract: A light control device 1 includes a light source 10, a prism 20, a spatial light modulator 30, a drive unit 31, a control unit 32, a lens 41, an aperture 42, and a lens 43. The spatial light modulator 30 is a phase modulating spatial light modulator, includes a plurality of two-dimensionally arrayed pixels, is capable of phase modulation in each of these pixels in a range of 4? or more, and presents a phase pattern to modulate the phase of light in each of the pixels. This phase pattern is produced by superimposing a blazed grating pattern for light diffraction and a phase pattern having a predetermined phase modulation distribution, and with a phase modulation range of 2? or more.

Abstract: The modulator array includes a first optical modulator, which changes a shape a wavefront of an incident light into first wavefronts to modulate the incident light which passes through the first optical modulator; and a second optical modulator that changes a shape at least one of the first wavefronts into second wavefronts to modulate the light output from the first optical modulator.

Abstract: A modulating apparatus includes a branch that branches input light; a first modulating unit that modulates the phase of a first branch obtained by the branch; a second modulating unit that modulates a second branch obtained by the branch; a third modulating unit that is connected in series to the first modulating unit, transmits the first branch without branching the first branch, modulates the phase of light transmitted by controlling a refractive index of the light transmitted; a fourth modulating unit that is connected in series to the second modulating unit, transmits the second branch without branching the second branch, and modulates the phase of a light transmitted by controlling a refractive index of the light transmitted; and a coupler that couples the first branch modulated by the first and the third modulating units and the second branch modulated by the second and the fourth modulating units, at different intensities.

Abstract: Techniques are described to form an optical waveguide switch that could reach a very high extinction ratio. In particular, this disclosure describes an asymmetric MZI, in which different waveguide capacitor structures are used in two arms of the MZI: a first arm with a waveguide capacitor to achieve the mainly phase modulation and a second arm with a waveguide capacitor to achieve mainly the magnitude modulation, respectively. Using the asymmetric MZI in accordance with this disclosure, one can design an algorithm to achieve almost unlimited extinction ration during the switching operation.

Abstract: Disclosed are structures and methods for CMOS drivers that drive silicon optical push-pull Mach-Zehnder modulators (MZMs) with twice the drive voltage per interferometer arm as with prior art designs.

Abstract: A laser device includes a seed laser, a polarizer, a pseudorandom bit sequence (PRBS) pattern generator, and a phase modulator. The polarizer may be optically coupled to receive an output of the seed laser and may generate a polarization filtered output. The PRBS pattern generator may be configured to generate a PRBS pattern. The phase modulator may be configured to apply a PRBS modulation scheme to the polarization filtered output based on the PRBS pattern. The PRBS pattern may be generated to have a length above a first threshold for avoiding an occurrence of backward propagation being in phase with forward propagation in an active fiber receiving an output of the phase modulator when the pattern repeats and below a second threshold for phase mismatch in the active fiber.

Abstract: Provided is an optical pulse-generator and an optical pulse-generating method which are capable of generating an optical pulse train with an arbitrary pattern. An optical pulse-generator 1 includes a first optical modulator 21 configured to modulate input light using a first modulation signal SIG1 to generate optical pulses, a second optical modulator 41 configured to perform a modulation operation using a second modulation signal SIG2 synchronizing with the first modulation signal SIG1 and having a signal pattern that is set to output only specific part of the optical pulses, and a dispersion compensator 30 configured to compensate a chirp of the optical pulse output from the first optical modulator 21.

Abstract: A modular routing node includes a single input port and a plurality of output ports. The modular routing node is arranged to produce a plurality of different deflections and uses small adjustments to compensate for wavelength differences and alignment tolerances in an optical system. An optical device is arranged to receive a multiplex of many optical signals at different wavelengths, to separate the optical signals into at least two groups, and to process at least one of the groups adaptively.

Abstract: Provided are a wavelength swept source apparatus and a method for operating thereof. According to the provided apparatus and method, single mode light is generated, a basic optical comb including a plurality of light rays having identical frequency differences with adjacent light rays is generated by modulating the generated single mode light, and a plurality of optical combs, that includes same number of light rays as the plurality of light rays, has a different frequency band from that of the basic optical comb, and is distributed in a wider frequency band than that in which the basic optical comb is distributed, is generated by modulating the plurality of light rays. The plurality of light rays and light rays included in the plurality of optical combs are sequentially emitted according to frequencies of the plurality of light rays and the light rays included in the plurality of optical combs.

Abstract: A semiconductor electro-optical phase shifter may include a first optical action zone having a minimum doping level, a first lateral zone and a central zone flanking the first optical action zone along a first axis, doped respectively at first and second conductivity types so as to form a P-I-N junction between the first lateral zone and the central zone. The phase shifter may include a second optical action zone having a threshold doping level, and a second lateral zone flanking the second optical action zone with the central zone along the first axis doped at the first conductivity type so as to form a P-I-N junction between the second lateral zone and the central zone.

Abstract: A semiconductor electro-optical phase shifter comprises a central zone (I1, I2) having a minimum doping level; first and second lateral zones (N+, P+) flanking the central zone along a first axis, respectively N and P-doped, so as to form a P-I-N junction between the first and second lateral zones. The central zone comprises first and second optical action zones (I1, I2) separated along the first axis. The second lateral zone is doped discontinuously along a second axis perpendicular to the first axis. Two electrical control terminals (A, C) are provided, one in contact with the first lateral zone, and the other in contact with doped portions of the second lateral zone.

Abstract: This invention relates to a planar optical component and a design method thereof, the method including designing a structure with defined discrete phases; based on the structure with defined discrete phases as array elements, designing a 2D thin antenna array; constituting the planar optical component by a metal film having the 2D thin antenna array and a substrate. To achieve expected beam shaping effect, the method according to the embodiment of the present invention modulates structural parameters of antenna array elements to modulate the amplitude and phase of radiation field having vertical polarization states, which is excited by a beam having specific wavelengths and polarization states incident on the planar diffractive optical component. The planar diffractive optical component according to the embodiment of the present invention has little difference from expected parameters, and can achieve optimum beam shaping effect to make up the shortfall of conventional beam shaping elements.

Abstract: The invention relates to an apparatus and a method for modulation of an optical signal with a data signal, said apparatus (6) comprising a configurable digital encoding unit (8) encoding data of said data signal to provide an encoded modulation control signal (EMCS), and a signal modulation unit (9) modulating said optical signal with respect to its signal phase and/or signal amplitude in orthogonal polarization directions in response to said encoded modulation control signal (EMCS) to generate a multi-dimensional optical signal vector.

Abstract: A modulator bias selection method, a coherent optical transmitter, and optical modulator solve the problem of generating a correct constellation using the bias points with the minimum phase adjustment range. The optimum modulator bias systems and methods include a coherent optical transmitter with control of four (XI, XQ, YI, YQ) quadrature data signals via a transmitter (Tx) application specific integrated circuit (ASIC), with a modulator bias controller which implements an algorithm to find the optimum bias points. The optimum bias points yield a correct constellation with minimum phase/bias adjustment. An algorithm is used to find the optimum bias solution using fast, simple method, adjusting only one quadrature at a time and exploiting a control feature of the Tx ASIC. This algorithm is significantly simpler than a generalized search, is a local algorithm, and uses only DC power measurement at the transmitter.

Abstract: A system for modulating light using a micro-electro-mechanical structure includes a plurality of deformable mirror elements (30) having an L-shaped cross section. Each of the deformable mirror elements is comprised of a pedestal (32) and an elongated ribbon (33). Each of the ribbons has a reflective surface (35). A beam of light is directed on the deformable mirror elements. The deformable mirror elements is flexed about an axis parallel to a long dimension of the ribbons to vary a curvature of at least one of the reflective ribbons.

Abstract: An optical-path conversion device includes: a plate-shaped phase modulation mask in which a plurality of phase modulation parts are discretely formed for providing phase modulation to light passing through, and a first light-transmission part is formed for transmitting the light; and a plate-shaped light-shielding member in which a plurality of light-shielding parts are discretely formed for blocking the light, and a second light-transmission part is formed for transmitting the light, in which the phase modulation mask and the light-shielding member overlap each other at least in part, when viewed in an incident direction of the light, and at least one of the phase modulation mask and the light-shielding member is movable in an intersection direction which intersects with the incident direction.

Abstract: An optical device in which crosstalk due to scattering is reduced includes an optical port array having at least one optical input for receiving an optical beam and at least one optical output. The input and outputs extend along a common axis. A dispersion element receives the optical beam from the optical input and spatially separates the optical beam into a plurality of wavelength components. A focusing element focuses the plurality of wavelength components and a programmable optical phase modulator receives the focused plurality of wavelength components. The modulator is configured to steer the wavelength components to a selected one of the optical outputs. The programmable optical phase modulator is oriented with respect to the optical port array so that an axis along which the optical beam is steered is non-coincident with the common axis along which the input and outputs extend.

Abstract: Various implementations of the invention compensate for “phase wandering” in tunable laser sources. Phase wandering may negatively impact a performance of a lidar system that employ such laser sources, typically by reducing a coherence length/range of the lidar system, an effective bandwidth of the lidar system, a sensitivity of the lidar system, etc. Some implementations of the invention compensate for phase wandering near the laser source and before the output of the laser is directed toward a target. Some implementations of the invention compensate for phase wandering in the target signal (i.e., the output of the laser that is incident on and reflected back from the target). Some implementations of the invention compensate for phase wandering at the laser source and in the target signal.

Abstract: A spatial light modulator, a holographic image display including the same, and a method for spatially modulating light. The spatial light modulator modulates a phase of light that is incident on a plurality of pixels and includes a variable refractive index layer that has a refractive index which is variable based on one of an optical signal and an electrical signal, and a metal layer that is disposed on the refractive index-change layer, and a high refractive index layer on the metal layer. Light incident on the metal layer causes generation of a surface plasmon at an interface between the variable refractive index layer and the metal layer.

Abstract: A nested loop system for combining coherent laser beams, The system includes multiple laser amplifiers each configured for emitting one of the laser beams, an output beam splitter configured for sampling each laser beam and for coupling each sampled laser beam to an inner feedback loop module, an output beam sampler configured for splitting the combined beam into a primary and a sampled output beam and for coupling the sampled output beam to the inner feedback loop module, multiple inner loop phase modulators each paired with one of the laser amplifiers, and the inner feedback loop module. For each laser amplifier the inner feedback loop module is configured to use the sampled output beam and the sampled laser beam associated with that laser amplifier to create a different inner loop feedback signal and to couple that inner loop feedback signal to that laser amplifier paired inner loop phase modulator.

Abstract: A phase modulation apparatus has a light source outputting continuous light, two phase modulators, and an intensity modulator. The phase modulation apparatus is provided with an RZ phase modulation circuit, in which the phase modulators phase-modulate the continuous light from the light source with data signals input to the phase modulators and generate two phase modulation optical signals, a phase shifter shifts the phase of one phase modulation optical signal by ?/2, and an intensity modulator intensity-modulates a multiplexed signal, combined with the other phase modulation optical signal, with an input clock signal CLK to convert the signal into an RZ signal, and, thus, to output the RZ signal, and a phase control circuit which adjusts the phases of the phase modulation optical signals generated by the phase modulator of the RZ phase modulation circuit so that the output of the RZ phase modulation circuit is maximum.

Abstract: A wavelength selective optical switch device includes an incidence and exit part where a signal beam made of light of a multiplicity of wavelengths enters and a signal beam of a selected wavelength exits, a wavelength dispersion element that spatially disperses a signal beam according to the wavelength thereof and multiplexes reflected light, a condensing element that condenses the light dispersed by the wavelength dispersion element onto a two-dimensional plane, and a wavelength selection element that uses a multilevel optical phased array arranged in a position to receive incident light developed on an xy-plane made of an x-axis direction and a y-axis direction perpendicular thereto developed according to a wavelength, having a multiplicity of pixels arrayed in a lattice on the xy-plane, and that cyclically changes the phase shift amount in the y-axis direction to a sawtooth wave pattern for each pixel on the x-axis.

Abstract: The invention relates to an apparatus for generating a scannable optical delay for a beam of light and an apparatus for Fourier domain optical coherence tomography having said apparatus for generating a scannable optical delay in its reference arm (15). The light beam is directed to a pivotably driven mirror (10) from where it is reflected to a fixed mirror (12), and from there back retro reflected along the reference arm (5). Lens optics (9) are provided to ensure accurate optical alignment in several pivot positions of the pivotably driven mirror (10).

Abstract: An interferometer used for modulating an optical signal with an electrical signal is described, where the optical signal can be subsequently detected so as to sample and digitize the electrical signal. Nonlinear optical elements can be located inside the interferometer to reduce the minimum detectable electrical input signal size. The interferometer can contain more than two arms to improve the tolerable dynamic range of the electrical signal. In some cases some outputs of the interferometer are dependent on the electrical input frequency while others have minimal frequency dependence, thereby allowing the frequency of the input electrical signal to be measured more easily. Ideally the modulator operates in a push-pull mode with a single electrode for the input electrical signal. Such a modulator can be constructed by using appropriate optical delay elements.

Abstract: A simulation model is for an optical modulator that may include an optical phase shifter in a semiconductor material structure between two sections of an optical waveguide. The semiconductor material structure may include one of a P-N and P-I-N junction in a plane parallel to an axis of the optical waveguide. The model may include a diode configured to characterize an electrical behavior of the one of the P-N and P-I-N junction such that a change in a global refractive index of the optical phase shifter is expressed, by a coefficient, based upon an amount of charges in the one of the P-N and P-I-N junctions and raised to a power. The coefficient and the power may be empirical values based upon the semiconductor material and a wavelength.

Abstract: The disclosure discloses a method and an apparatus for determining a bias point of a modulator, wherein the method includes: adding pilot signals to the bias voltages of the modulator; adjusting the bias point of the modulator at a predetermined step and acquiring a first harmonic amplitude value corresponding to each bias point in a backlight detection current signal output by the modulator; and determining a bias point corresponding to the maximum value of the first harmonic amplitude values associated with multiple bias points as the bias point of the modulator. By virtue of the disclosure, the detection of a difference frequency signal can be eliminated, thereby reducing the complexity and cost of a periphery control circuit while ensuring the control accuracy, effectively improving the stability and reliability of the control process, and improving the modulation and transmission performance of optical signals in the whole system.

Abstract: A nested loop system for combining coherent laser beams, The system includes multiple laser amplifiers each configured for emitting one of the laser beams, an output beam splitter configured for sampling each laser beam and for coupling each sampled laser beam to an inner feedback loop module, an output beam sampler configured for splitting the combined beam into a primary and a sampled output beam and for coupling the sampled output beam to the inner feedback loop module, multiple inner loop phase modulators each paired with one of the laser amplifiers, and the inner feedback loop module. For each laser amplifier the inner feedback loop module is configured to use the sampled output beam and the sampled laser beam associated with that laser amplifier to create a different inner loop feedback signal and to couple that inner loop feedback signal to that laser amplifier paired inner loop phase modulator.

Abstract: A microscope apparatus includes a laser beam source for emitting a laser beam, an objective lens for irradiating a sample with the laser beam, a phase-modulating spatial light modulator placed between the laser beam source and the objective lens at a position optically conjugate with a pupil position of the objective lens, and a beam diameter variable unit placed between the laser beam source and the phase-modulating spatial light modulator for varying a beam diameter of the laser beam incident to the phase-modulating spatial light modulator.

Abstract: A method for manufacturing a semiconductor optical modulator includes forming a p-type semiconductor layer on a main surface of a p-type semiconductor substrate; forming a pair of stripe-shaped masks on the p-type semiconductor layer, the stripe-shaped masks extending in a first direction along the main surface of the p-type semiconductor substrate and being spaced apart from each other; simultaneously forming a hole and a pair of stripe structures extending in the first direction by etching the p-type semiconductor layer through the stripe-shaped masks, the pair of stripe structures defining the hole; after removing the stripe-shaped masks, forming a buried layer in the hole; forming a core layer on the buried layer and the stripe structures; and forming an upper cladding layer on the core layer. The buried layer is made of a semiconductor material with a lower optical absorption loss than that of the p-type semiconductor layer.

Abstract: A laser device includes a seed laser, a polarizer, a pseudorandom bit sequence (PRBS) pattern generator, and a phase modulator. The polarizer may be optically coupled to receive an output of the seed laser and may generate a polarization filtered output. The PRBS pattern generator may be configured to generate a PRBS pattern. The phase modulator may be configured to apply a PRBS modulation scheme to the polarization filtered output based on the PRBS pattern. The PRBS pattern may be generated to have a length above a first threshold for avoiding an occurrence of backward propagation being in phase with forward propagation in an active fiber receiving an output of the phase modulator when the pattern repeats and below a second threshold for phase mismatch in the active fiber.

Abstract: A phase-controllable magnetic mirror, system, and method of use are described. The mirror has a ground plate with a surface, a dielectric layer disposed over the surface and having a plurality of electrically-isolated dielectric sections, the dielectric sections defining a plurality of unit cells. The unit cells change their dielectric constant based on an applied voltage such that cells incident photons having a first phase and re-emit photons having a second, different phase. A method of use includes aberrating a wave front and re-emitting, with a phase-controllable magnetic mirror, a second wave front having a different wave front contour. A system including the phase-controllable magnetic mirror has a processor configured to receive aberration measurements and provide selected bias voltages or illumination of the unit cells to make the re-emitted wave front have less aberration than the incident wave front.