Abstract: A projector comprises: a light source that projects laser light; a first color filter including a reflective portion reflecting the laser light emitted from the light source, and a transmissive portion transmitting the laser light; a phosphorus plate that converts the laser light reflected from the first color filter into phosphorescent light; a second color filter including color films of different colors through which the phosphorescent light transmits; and a display element that is provided with the laser light transmitted from the first color filter and the phosphorescent light transmitted through the second color filter so as to project an image, wherein the projector can be reduced in volume since the number of lenses used in an optical system can be reduced by shortening an optical path.

Abstract: An emission enhancement structure having at least one energy augmentation structure; and an energy converter capable of receiving energy from an energy source, converting the energy and emitting therefrom a light of a different energy than the received energy. The energy converter is disposed in a vicinity of the at least one energy augmentation structure such that the emitted light is emitted with an intensity larger than if the converter were remote from the at least one energy augmentation structure. Also described are various uses for the energy emitters, energy augmentation structures and energy collectors in a wide array of fields, such as color enhancement, and color enhancement structures containing the same.

Abstract: A prism module of a camera lens includes a fixed holder, a rotary holder, a prism mounted on the rotary holder, a rotation driver assembly provided between the fixed holder and the rotary holder, and a circuit board. The rotary holder includes a base and a rotation driver bracket. The rotation driver assembly is made of memory alloys and deformed, under control of an electrical signal transmitted from the circuit board, to drive the base to rotate. The base and the rotation connecting bracket are directly connected to each other, simplifying the structure of the prism module and reducing the production cost of the prism module. The rotation driver assembly drives the rotary holder and the prism to rotate relative to the fixed holder, in such a manner that the prism can be driven by the rotation driver assembly to automatically correct its angle, thereby providing clearer imaging effect.

Abstract: A device and method for the pre-display of a spot pattern to be applied for a laser treatment of the eye. The spot patterns to be applied are displayed to the operator in advance with the aid of a target beam. The device for the pre-display of a spot pattern to be applied for a laser treatment of the eye includes a laser system and a scanning system for generating a target beam. Here, the laser system and the scanning system for generating the target beam are formed to generate one or more lines which overlie all the spots of the spot pattern of a planned laser treatment. The device and method are suitable for laser treatment of the retina, the trabecular meshwork as well as other regions. Here, it is irrelevant whether what the laser treatment to be applied is.

Abstract: The described method and system allow the simultaneous detection of multicolored samples, e.g. in live cells or tissues, in a simple experimental geometry. It relies on combining ultrashort ultra-broadband laser sources (10) with a fluorescence microscope setup able to collect fluorescence intensities and/or photon arrival times per excitation volume, as well as nonlinear signals, such as second/third-harmonic and sum-frequency generation. In the description, the presented method is referred to as “SyncRGB method”.

Abstract: An optical power transmission apparatus includes: a light emitting unit including a first optical gain generating means and a first light reflecting means; an optical fiber; a second light reflecting means; and a light receiving means. Further, the second light reflecting means is arranged nearer to the light receiving means than the optical fiber is, a first laser resonator is formed, between the first light reflecting means and the second light reflecting means, by optical connection between the first optical gain generating means and the optical fiber, and first laser light generated by the first laser resonator is configured to be incident on the light receiving means.

Abstract: An arrangement is disclosed. The arrangement comprises at least one semiconductor structure configured to convert a primary radiation into a secondary radiation; an encapsulation layer covering the at least one semiconductor structure; and at least one reflective layer arranged on the encapsulation layer. The semiconductor structure is arranged in a center of the arrangement, and a lateral extent of the arrangement is chosen such that an optically resonant condition is fulfilled for a wavelength of the secondary radiation in the encapsulation layer. Methods for producing an arrangement and an optoelectronic device are also disclosed.

Abstract: An optical frequency comb light source and an optical frequency comb generation method, where the light source includes a laser diode, a coupler, a Kerr nonlinear device, a beam splitter, and a phase shifter. The laser diode is connected to one input port of the coupler, and the other input port of the coupler is connected to an output port of the phase shifter. An output port of the coupler is connected to an input port of the Kerr nonlinear device. An output port of the Kerr nonlinear device is connected to an input port of the beam splitter. One output port of the beam splitter is connected to an input port of the phase shifter. The other output port of the beam splitter is configured to output a plurality of optical frequency combs. A multi-wavelength light source with relatively high power may be provided.

Abstract: A laser source includes a first laser device configured to generate a first laser beam having a first wavelength, a second laser device configured to generate a second laser beam having a second wavelength, which is different from the first wavelength, and a non-linear crystal configured to receive simultaneously the first and second laser beams and to generate a third laser beam that has a third wavelength, which is larger than each of the first and second wavelengths. The non-linear crystal has a length and a width, and a variable poling period is distributed across the width so that the third wavelength varies within a given wavelength range based on an incident position of the first and second laser beams along the width of the non-linear crystal.

Abstract: A quantum computer executes quantum measurement of <?1|Pi|?2>, <?1|Uij,+|?2>, <?1|Uij,?|?2>, <?1|Pj|?2>, and <?1|PiPj|?2< below based on a quantum state pair configured by a first quantum state ?1 and a second quantum state ?2, and outputs measurement results of the quantum measurement. A classical computer computes a transition amplitude |<?1|A|?2>|2 based on measurement results for <?1|Pi|?2>, <?1|Uij,+|?2>, <?1|Uij,?|?2>, <?1|Pj|?2>, and <?1|PiPj|?2>, wherein A is a physical quantity for computation of transition amplitude, i and j are indices for identifying a and P, a is a real number, P is a tensor product of a Pauli matrix, U is a unitary gate, and <?1|?2>=0.

Abstract: The present invention provides a laser, including: a medium, having a ground state, an intermediate state, and an excited state in ascending order of energy; an excitation system, configured to excite electrons in the medium from the ground state to the intermediate state; and an excitation laser, configured to drive electrons in the intermediate state at different spatial positions in the medium to the ground state through a stimulated emission process with a fixed phase relationship, to generate a laser with a shorter relative wavelength. Due to the use of an excitation laser to drive electrons from the intermediate state, the photons generated by the stimulated emission have coherence, thereby forming a laser.

Abstract: An apparatus for spectral broadening of laser pulses includes a main body, a plurality of mirror elements fastened to the main body, each having a mirror surface formed thereon and configured to reflect the laser pulses the plurality of mirror elements being fastened to a main body, and at least one nonlinear optical medium for the passage of the laser pulses for the generation of a nonlinear phase (?NL) by self-phase modulation. The at least one nonlinear optical medium may be a sheet-like and disk-shaped solid-state optical medium and/or a gaseous optical medium.

Abstract: In this disclosure, quantum algorithms are presented for simulating Hamiltonian time-evolution e?i(A+B)t in the interaction picture of quantum mechanics on a quantum computer. The interaction picture is a known analytical tool for separating dynamical effects due to trivial free-evolution A from those due to interactions B. This is especially useful when the energy-scale of the trivial component is dominant, but of little interest. Whereas state-of-art simulation algorithms scale with the energy ?A+B???A?+?B? of the full Hamiltonian, embodiments of the disclosed approach generally scale linearly with the sum of the Hamiltonian coefficients from the low-energy component B and poly-logarithmically with those from A.

Abstract: A method of training a quantum computer employs quantum algorithms. The method comprises loading, into the quantum computer, a description of a quantum Boltzmann machine, and training the quantum Boltzmann machine according to a protocol, wherein a classification error is used as a metric for the protocol.

Abstract: A wavelength division multiplexing device includes a common port and a plurality of filters that define an optical path. The common port includes a collimator that transmits an optical beam including a plurality of optical signals. Each optical signal is associated with a different wavelength range, and each filter includes an interface having a radius of curvature. One filter is configured to receive the optical beam from the collimator, transmit an optical signal through its interface, and reflect the remaining portion of the optical beam toward another filter. The common collimator and filter are configured so that the reflected portion of the optical beam has a beam waist located in the optical path midway between the filters, and a wavefront radius of curvature at the other filter that matches the filter radius of curvature of that filter. A method of processing light in such a device is also disclosed.

Abstract: In a conventional RGB coupler, the split ratio largely depends on the wavelength. The split ratio of R and the split ratios of G and B are non-uniform because R has a wavelength far from those of G and B. Accordingly, a video display device needs to have the monitoring detection value corrected, making it difficult to use the monitoring function. A light combining circuit and a light source of this disclosure include a first splitting unit for splitting R wavelength light and a second splitting unit for splitting G and B combined light. They split monochromatic light of R and combined light of G and B, independently. G and B light from an LD are first combined by a preliminary wave-combining unit before being split. The split lights of each wavelength are combined by a main wave-combining unit, outputting RGB combined light. Each split light from the two splitting units is detected by a single PD.

Abstract: An optical wireless communications receiver for a portable communications device, the receiver being configured to receive radiation signals on which communication data is encoded, wherein the receiver is comprised in or on or configured for mounting to at least part of a periphery or edge of the device. Advantageously, the optical wireless communications comprises a plurality of, receiver elements distributed along or around the receiver and/or comprises an optical guide configured to receive radiation and convey at least part of the radiation along the optical guide to at least one of the receiver elements.

Abstract: In this disclosure, quantum algorithms are presented for simulating Hamiltonian time-evolution e?i(A+B)t in the interaction picture of quantum mechanics on a quantum computer. The interaction picture is a known analytical tool for separating dynamical effects due to trivial free-evolution A from those due to interactions B. This is especially useful when the energy-scale of the trivial component is dominant, but of little interest. Whereas state-of-art simulation algorithms scale with the energy ?A+B???A?+?B? of the full Hamiltonian, embodiments of the disclosed approach generally scale linearly with the sum of the Hamiltonian coefficients from the low-energy component B and poly-logarithmically with those from A.

Abstract: A degenerate four-wave mixing (DFWM) squeezed light apparatus includes one or more pump beams, a probe beam, a vapor cell, a repump beam, and a detector. The one or more pump beams includes an input power of no greater than about 150 mW. The vapor cell includes an atomic vapor configured to interact with overlapped pump and probe beams to generate an amplified probe beam and a conjugate beam. The repump beam is configured to optically pump the atomic vapor to a ground state and decrease atomic decoherence of the atomic vapor. The detector is configured to measure squeezing due to quantum correlations between the amplified probe beam and the conjugate beam. The one or more pump beams, the probe beam, and the repump beam are configured to generate two-mode squeezed light by DFWM with squeezing of at least 3 dB below shot noise.

Abstract: Disclosed here are methods, devices, and systems for generating an output light beam for a pulsed laser. An example method may comprise generating one or more pump optical beams comprising at least two photons having a pump wavelength. A first nonlinear stage may convert the at least two photons to a first photon having a first wavelength that is half of the pump wavelength. The first optical beam may be caused to spatially overlap with a seed optical beam. At least two second nonlinear stages separated by a gap may be used to convert, based on the seed optical beam, the first photon to a second photon having a second wavelength and a third photon having a target wavelength greater than the pump wavelength. A third nonlinear stage may convert the second photon to a fourth photon and a fifth photon each having the target wavelength or having a wavelength within an offset range of the target wavelength.

Abstract: Examples of the present disclosure include the use of a topological system including an array of coupled ring resonators that exhibits topological edge states to generate frequency combs and temporal dissipative Kerr solitons. The topological edge states constitute a travelling-wave super-ring resonator causing generation of at least coherent nested optical frequency combs, and self-formation of nested temporal solitons that are robust against defects in the array at a mode efficiency exceeding 50%.

Abstract: A method for producing a rare earth aluminate fluorescent material, including: preparing, as raw materials, cerium oxide having a crystallite diameter in a range of 200 ? or more and 1,600 ? or less, a compound containing at least one kind of a rare earth element Ln selected from the group consisting of Y, La, Lu, Gd, and Tb, a compound containing Al, and depending on necessity a compound containing at least one kind of an element M1 selected from the group consisting of Ga and Sc, wherein a total molar ratio of the rare earth element Ln and cerium is 3, a total molar ratio of Al and the element M1 is a product of a parameter k in a range of 0.95 or more and 1.05 or less and 5, a molar ratio of cerium is a product of a parameter n in a range of 0.005 or more and 0.050 or less and 3, and a molar ratio of the element M1 is a product of a parameter m in a range of 0 or more and 0.02 or less, the parameter k, and 5; and subjecting a mixture of the raw materials to a heat treatment to provide a calcined product.

Abstract: A quantum computing system for converting Pauli errors of one or more qubits to erasure errors in a photonic quantum computing architecture. Two or more photonic qubits may be input to a quantum computing system, where at least one first qubit of the two or more qubits has experienced a Pauli error. A sequence of linear optical circuitry operations may be performed on the two or more qubits to generate two or more modified qubits, wherein the sequence of operations transforms one or more of the first qubits from a logical subspace of a Fock space to an erasure subspace of the Fock space. A cluster state for universal quantum computing may be generated from the two or more modified qubits using probabilistic entangling gates. A quantum computational algorithm may be performed using the quantum cluster state generated from the two or more modified qubits.

Abstract: A technique to generate terahertz radiation is disclosed, where a pump beam (12) is coupled into an optical element (50) made of a medium with non-linear optical properties having plane-parallel front and rear boundary surfaces (51, 52), wherein the pump beam (12) is split into a set of partial pump beams (121) by reflection and/or diffraction on a periodic relief structure (53) of said optical element (50). The partial pump beams travel along a direction at an angle ? that satisfies the velocity matching condition of vp,cs cos(?)=vTHz,f within the given medium, where vp,cs is the group velocity of the pump beam, vTHz,f is the phase velocity of the terahertz radiation and the speed a planar envelope (212) travels toward the front boundary surface (51) of the optical element (50), and angle ? is the angle formed by the pulse front envelope and the phase front of the pump beam.

Abstract: It remains a challenge to generate coherent radiation in the spectral range of 0.1-10 THz (“the THz gap”), a band for applications ranging from spectroscopy to security and high-speed wireless communications. Here, we disclose how to produce coherent radiation spanning the THz gap using efficient second-harmonic generation (SHG) in low-loss dielectric structures, starting from an electronic oscillator (EO) that generates coherent radiation at frequencies of about 100 GHz. The EO is coupled to cascaded, hybrid THz-band dielectric cavities that combine (1) extreme field concentration in high-quality-factor resonators with (2) nonlinear materials enhanced by phonon resonances. These cavities convert the input radiation into higher-frequency coherent radiation at conversion efficiencies of >103%/W, making it possible to bridge the THz gap with 1 W of input power.

Abstract: The embodiments described herein provide a high-luminous flux laser-based white light source. A plurality of laser packages are arranged in an array pattern on a common support member. The plurality of laser packages each include one or more laser diode devices and a phosphor member. The phosphor member converts a fraction of the electromagnetic radiation from each of the laser diode devices to an emitted electromagnetic radiation and a white light is outputted.

Abstract: There is provided a design of a device consisting of a patterned semiconductor material to provide enhanced detection bandwidth and efficiency of terahertz (THz) pulses with an electro-optic sampling. One device has a semiconductor crystal having a patterned grating on a surface of the semiconductor. In a system, there could optionally be a quarter-wave plate after the semiconductor crystal, followed by a prism. A pair of balanced photodiodes can optionally be provided after the prism. A pulse laser having a NIR beam and THz beam is sent through the semiconductor crystal to the quarter-wave plate to the prism to the photodiodes, wherein the patterned grating on the semiconductor crystal diffracts the NIR beam while the THz remains unaffected. The photodiodes can detect the result.

Abstract: A wavelength-converting device has a light incident side. The wavelength-converting device includes an inner annular portion and an annular portion. The annular portion is connected to an outer edge of the inner annular portion. The annular portion includes a wavelength-converting portion, a first heat-conductive bonding medium, a reflective layer, and a wavelength-converting layer. A groove is annularly disposed in the wavelength-converting portion, and the groove is recessed from the light incident side of the wavelength-converting device. The first heat-conductive bonding medium is disposed in the groove. The reflective layer is disposed on the first heat-conductive bonding medium. The wavelength-converting layer is disposed on the reflective layer and has a light receiving surface. A projection apparatus is also provided.

Abstract: The present invention relates to an optical measuring system comprising a polymer-based single-mode fibre-optic sensor system (102), an optical interrogator (101), and an optical arrangement (103) interconnecting the optical interrogator (101) and the polymer-based single-mode fibre-optic sensor system (102). The invention further relates to an optical interrogator adapted to be connected to a polymer-based single-mode fibre-optic sensor system via an optical arrangement. The interrogator comprises a broadband light source arrangement (104) and a spectrum analysing arrangement which receives and analyses light reflected from the polymer-based single-mode fibre-optic sensor system.

Abstract: A wavelength converter including: A. a crystal holder configured to hold a nonlinear crystal configured to convert a wavelength of a laser beam incident thereon and output the wavelength-converted laser beam; B. a first container configured to accommodate the crystal holder and include a light incident window so provided as to intersect an optical path of the laser beam incident on the nonlinear crystal and a light exiting window so provided as to intersect the optical path of the laser beam having exited out of the nonlinear crystal; C. a second container configured to accommodate the first container; D. a position adjusting mechanism configured to adjust at least a position of the first container; and E. an isolation mechanism configured to spatially isolate the light incident window and the light exiting window from the position adjusting mechanism.

Abstract: A system and apparatus for increasing the amplitude of accommodation and/or changing the refractive power and/or enabling the removal of the clear or cataractous lens material of a natural crystalline lens is provided. Generally, the system comprises a laser, optics for delivering the laser beam and a control system for delivering the laser beam to the lens in a particular pattern. There is further provided a range determining system for determining the shape and position of the lens with respect to the laser. There is yet further provided a method and system for delivering a laser beam in the lens of the eye in a predetermined shot pattern.

Abstract: A method includes receiving input light having an input wavelength in a first optical resonator for causing resonance of the input light in the first optical resonator. The first optical resonator includes a non-linear optical medium. The method also includes converting at least a portion of the input light to a combination of first output light having a first output wavelength that is different from the input wavelength and second output light having a second output wavelength that is different from the input wavelength and the first output wavelength by passing the input light through the non-linear optical medium. The method further includes causing resonance of the first output light and the second output light in a second optical resonator. A portion of the first optical resonator is coupled to a portion of the second optical resonator.

Abstract: A transparent panel includes a first substrate, a second substrate, and a plurality of pixel regions. The second substrate is opposite to the first substrate. The plurality of pixel regions are between the first substrate and the second substrate. Each of the pixel regions includes a first region and a second region. A scattering degree of the first region is greater than a scattering degree of the second region. An area ratio of the first region to the second region in a pixel region increases as a distance between the pixel region and at least one side of the transparent panel increases.

Abstract: Provided is a structured light projector including a light source configured to emit light, and a nanostructure array configured to form a dot pattern based on the light emitted by the light source, the nanostructure array including a plurality of super cells each respectively including a plurality of nanostructures, wherein each of the plurality of super cells includes a first sub cell that includes a plurality of first nanostructures having a first shape distribution and a second sub cell that includes a plurality of second nanostructures having a second shape distribution.

Abstract: An optical signal transmission apparatus including a temperature-independent wavelength tunable laser includes a distributed Bragg reflector (DBR) laser including a DBR mirror region configured to convert a wavelength of an output optical signal based on a first supply current, and an optical gain region configured to control a gain of the output optical signal based on a second supply current, a semiconductor optical amplifier (SOA) configured to amplify an optical signal output from the DBR laser based on a third supply current, and a processor configured to supply a compensation current to the optical gain region based on a wavelength conversion request, to suppress a wavelength overshoot due to a carrier effect caused by the first supply current provided to the DBR mirror region.

Abstract: An optical device may include an optic disposed in an optical path. The optical device may include a mount to dispose the optic in the optical path. The optical device may include a plurality of spring clamps to attach the optic to the mount. The spring clamp, of the plurality of spring clamps, may include a body, a spring, and a screw. The screw may be to attach to the mount and to compress the spring. The spring may be to dispose a leading edge of the body against the optic. The spring clamp may be to maintain the optic in the optical path for a thermal cycle of at least between approximately ?50° C. and approximately 130° C.

Abstract: An ultrafast electro-optic laser makes a stabilized comb and includes: a comb generator that produces a frequency comb; a dielectric resonant oscillator; a phase modulator in communication with the dielectric resonant oscillator; an intensity modulator in communication with the phase modulator; an optical tailor in communication with the comb generator and that produces tailored light; a filter cavity in communication with the intensity modulator; a pulse shaper in communication with the filter cavity; a highly nonlinear fiber and compressor in communication with the pulse shaper; an interferometer in communication with the optical tailor and that produces a difference frequency from the tailored light; and an electrical stabilizer in communication with the interferometer and the comb generator and that produces the stabilization signal with a stabilized local oscillator cavity that produces a stabilized local oscillator signal that is converted into the stabilization signal and communicated to the dielectric

Abstract: A wavelength converter includes an excitation light source outputting excitation light, a beam splitter receiving an input of the excitation light and an input of the optical signal and to divide both the inputted excitation light and the inputted optical signal into a first polarization component and a second polarization component, a non-linear optical fiber as a non-polarization-maintaining fiber, an accommodation section securing and accommodating the non-linear optical fiber, a first collimator lens disposed between the beam splitter and a first end of the non-linear optical fiber, and a second collimator lens disposed between the beam splitter and a second end of the non-linear optical fiber, wherein the optical signal is inputted to the beam splitter from a direction different from the input of the excitation light.

Abstract: A HUD device comprising a display device for scanning with light emitted by a light source (e.g., an LD) an optical element array (e.g., a micro lens array) including multiple optical elements (e.g., micro lenses) to form an image and for projecting the light that has formed the image. The display device includes a control unit 8060 that is capable of changing output power of the light In this case, it is possible to provide a display device that is capable of adjusting luminance of an image while controlling against luminance unevenness of the image from occurring.

Abstract: A wavelength converter includes a first phase modulator configured to perform phase modulation on pump light in accordance with a first phase modulation signal, a second phase modulator configured to perform phase modulation on signal light in accordance with a second phase modulation signal, a wavelength converter configured to multiplex the signal light having undergone the phase modulation with the pump light having undergone the phase modulation, the wavelength converter configured to perform wavelength conversion on the signal light in accordance with the pump light, a detector configured to detect a modulation component from the signal light having undergone the phase modulation and the pump light having undergone the phase modulation, and a generator configured to generate the first phase modulation signal and the second phase modulation signal so as to minimize the detected modulation component.

Abstract: A super structure grating spatially performs amplitude and phase modulation on a uniform grating using a modulation function to generate a comb reflection spectrum. (N+1) modulation function discrete values are obtained after discretization processing is performed on the modulation function using N thresholds. Each of the (N+1) modulation function discrete values corresponds to one section of optical waveguide whose refractive index is uniform or corresponds to one section of the uniform grating. A reflectivity and a full width half maximum (FWHM) of a reflection peak of the super structure grating is adjusted based on a relationship of a ratio of a length of an optical waveguide corresponding to at least one of the (N+1) modulation function discrete values to a total grating length of the super structure grating, and based on the total grating length of the super structure grating.

Abstract: Disclosed herein are systems and methods for the characterization of transmission media, among other embodiments. For example, a system for characterizing a transmission medium may include: a waveform generator to generate an initial input waveform; waveform pre-processing circuitry to process the initial waveform to generate a processed input waveform for provision to the transmission medium, wherein the processed input waveform has a maximum amplitude greater than a maximum amplitude of the initial input waveform; and waveform output circuitry to display or store data representative of an initial output waveform, wherein the initial output waveform is output from the transmission medium as a reflection or transmission of the processed input waveform.

Abstract: Methods and systems for providing eye-safe compatible receiver for a light detection and ranging system. The light detection and ranging system comprises; an emitting unit comprising a light source configured to emit a sequence of light pulses of a first wavelength into a three-dimensional environment; and a receiving module comprising a detector for detecting light pulses of a second wavelength, in which the second wavelength is shorter than the first wavelength, the receiving module further comprising a wavelength converter coupled to the detector and configured to convert an echo signal of the emitted light pulses into the light pulses of the second wavelength.

Abstract: There is provided a reconfigurable optical modulator comprising a light source and a splitter operative to receive an input signal from the light source and to split the input signal into a plurality of split signals. The optical modulator comprises a plurality of optical amplifiers, each being operative to receive one of the plurality of split signals as an input and to act as a switch having a first state where the split signal is blocked and a second state where the split signal is amplified. The optical modulator comprises a plurality of modulators, each being operative to receive an amplified split signal from one of the plurality of optical amplifiers and to modulate the amplified split signal into a modulated signal. The optical modulator comprises an optical combiner operative to combine a plurality of modulated signals produced by the plurality of modulators to thereby produce a modulated output signal.

Abstract: A nonlinear crystal comprising a first curved face and an opposing second curved face is described. The first and second curved faces are arranged to provide the nonlinear crystal with rotational symmetry about at least one axis of the nonlinear crystal. The nonlinear crystal allows for frequency tuning of a generated optical field that is generated by propagating a fundamental optical field through the nonlinear crystal by rotation of the nonlinear crystal about an axis of rotation without any significant, or minimal, deviation being introduced to the generated optical field. These nonlinear crystals can therefore be incorporated into an external cavity frequency doubler or mixer without any need for the employment of optical compensation optics or servo control electronics to automatically realign the cavity mirrors.

Abstract: An optical crystal for converting an input light beam, the crystal having an ingress surface, an egress surface, and a fan-out grating has a fan-out pattern oriented at an offset angle ? in the range of 1° to 45° with respect to a beam entry plane at a beam ingress location.

Abstract: In an aspect, an optical device includes a substrate, a light source mounted on a top surface of the substrate, and a lid attached to the top surface of the substrate, the lid defining a reflective cup positioned over the light source. In another aspect, an optical device includes a substrate, a light source disposed on the substrate, and a lid disposed on the substrate. The lid defines a reflective cup for concentrating and passing light from the light source. The optical device further includes a film formed on an inner sidewall of the reflective cup for reflecting the light from the light source. The film includes a primer layer, a reflecting layer and a protective layer.

Abstract: In example embodiments, a radiation source uses Rydberg states to generate coherent THz radiation (e.g., in the range of 1-20 THz). The radiation source includes a pair of pump lasers (e.g., external-cavity diode lasers (ECDLs)) optically coupled (e.g., by a dichroic mirror and optical fiber) to a heated vapor cell (e.g., a vacuum chamber) holding an atomic species (e.g., rubidium (Rb)). The pump lasers optically pump the atomic species (e.g., Rb) to a predetermined Rydberg state (e.g., the nD5/2 state), which creates a population inversion between that state (e.g., the nD5/2 state) and a lower lying Rydberg state (e.g., the (n+1)P3/2 state). The emission between these two strongly dipole coupled Rydberg states generates coherent THz radiation.

Abstract: The present invention discloses a method for controlling spectral properties of optical quantum states using quantum interference in cascaded waveguide structure comprises the following steps: adopting a multi-stage cascaded waveguide structure sequentially consisting of a segment of nonlinear medium, a segment of dispersive medium, . . . and a segment of nonlinear medium, or adopting a two-stage cascaded waveguide structure sequentially consisting of a segment of nonlinear medium, a segment of dispersion-controllable dispersive medium and a segment of nonlinear medium; pumping the multi-stage cascaded waveguide structure or two-stage cascaded waveguide structure by using pulsed laser to generate optical quantum states through the cascaded parametric process in the cascaded waveguide structure. The spectral property of the optical quantum state can be flexibly adjusted by changing the number of stages, the length and dispersion property of the dispersive media.

Abstract: Disclosed is a method of performing a measurement in an inspection apparatus, and an associated inspection apparatus and HHG source. The method comprises configuring one or more controllable characteristics of at least one driving laser pulse of a high harmonic generation radiation source to control the output emission spectrum of illumination radiation provided by the high harmonic generation radiation source; and illuminating a target structure with said illuminating radiation. The method may comprise configuring the driving laser pulse so that the output emission spectrum comprises a plurality of discrete harmonic peaks. Alternatively the method may comprise using a plurality of driving laser pulses of different wavelengths such that the output emission spectrum is substantially monochromatic.