593 results about "Long wavelength" patented technology

Disclosed is a three-dimensional deformation field modeling method fusing global navigation satellite system (GNSS) / synthetic aperture radar interferometry (InSAR) observation data. The three-dimensional deformation field modeling method includes: five parts of solving an InSAR line-of-sight velocity field, unifying a spatial reference datum of the GNSS data and the InSAR data, verifying precision of a result of the InSAR data, solving a three-dimensional deformation field having high precision based on a least square method, and analyzing and verifying a result. According to the method, the InSAR data is processed according to a high-precision time series method, a long-wavelength error of the InSAR data is corrected on the basis of a difference of two data spatial reference datums, and the accuracy of the result is ensured through verification of internal coincidence precision.

The invention provides a perovskite laminated photovoltaic cell assembly and a preparation method thereof, the perovskite laminated photovoltaic cell assembly comprises a plurality of first battery packs connected in parallel, each first battery pack comprises a plurality of laminated cells connected in series, and each laminated cell comprises a perovskite cell and a crystalline silicon cell which are stacked; a first light absorption layer and a first hole transport layer of the perovskite cell are etched by P2 laser to form a plurality of perovskite sub-cells which are connected in parallel, and the perovskite cell is used for absorbing short-wavelength light in front sunlight; the second hole transport layer and the intermediate electrode layer of the crystalline silicon cell are etched by P1 laser to form a plurality of crystalline silicon sub-cells which are connected in parallel, the perovskite cell is used for absorbing long-wavelength light in front sunlight, and the absolute value of the difference between the current density of the perovskite cell and the current density of the crystalline silicon cell is smaller than or equal to a first preset value. According to the laminated battery piece, the current density consistency of the perovskite battery and the crystalline silicon battery in the laminated battery piece is high, the electrical loss can be reduced, and the power generation efficiency can be improved.

A display device capable of performing display at high luminance is provided. A first layer containing a first light-emitting material emitting blue light is formed into an island shape over a first pixel electrode, and then a second layer containing a second light-emitting material emitting light having a longer wavelength than blue light is formed into an island shape over a second pixel electrode. After that, an insulating layer overlapping with a region interposed between the first pixel electrode and the second pixel electrode is formed, and a common electrode is formed to cover the first layer, the second layer, and the insulating layer.

The invention belongs to the technical field of ceramics and slurry thereof, and particularly relates to fiber-reinforced ceramic photocuring slurry, a preparation method and a reinforced ceramic material. The slurry provided by the invention consists of ceramic powder, ceramic composite short fibers, light-cured resin, a photoinitiator, a dispersing agent, a plasticizer and the like, wherein the ceramic composite short fibers are zirconium oxide and silicon oxide composite fibers; the light-cured resin contains a photosensitive resin monomer and a prepolymer; and the photoinitiator is compounded by a short-wavelength initiator and a long-wavelength initiator. The preparation method comprises the following steps: modifying the ceramic composite short fibers with a silane coupling agent, mixing the modified ceramic composite short fibers with all the materials, and carrying out ball milling and defoaming. The obtained slurry is subjected to 3D printing photocuring molding and degreasing sintering, and a reinforced ceramic material can be prepared. The slurry can be used for manufacturing a high-performance ceramic material through composite short fiber synergistic enhancement, long and short wavelength initiator synergistic curing and fiber surface modification, and the curing depth, the three-point bending strength and the fracture toughness are remarkably improved.

Methods and systems for providing a dataset of human in-bed poses include simultaneously gathered images of in-bed poses of humans from imaging modalities including red-green-blue (RGB) and one or more of long wavelength infrared (LWIR), depth imaging, and pressure mapping. The images are obtained under a lighting condition and a cover condition. The dataset can be used to train a model of estimating human in-bed poses and for methods of estimating human in-bed poses. Methods and systems of estimating three-dimensional human poses from two-dimensional input images are provided.

The invention discloses a tunable excited Raman spectrum microimaging method and device, and belongs to the field of spectrum detection and optical imaging. The device comprises a broadband adjustable wavelength light source, a high-resolution wavelength scanning module, a stimulated Raman signal excitation module and a stimulated Raman signal detection module. The stimulated Raman signal excitation and imaging module is used for focusing the two beams of narrow-band femtosecond pulse light which are overlapped in time and space on a sample and exciting a stimulated Raman signal, and meanwhile, moving the sample to realize spot scanning microscopic imaging; and the stimulated Raman signal detection module is used for converting the stimulated Raman scattering signal into an electric signal, demodulating the electric signal by using a lock-in amplifier, and recording spectral information by using a data acquisition card. According to the invention, the broadband tunable characteristic of the optical parametric amplifier is utilized to tune the pump light to the wavelength region of the sample absorption peak length so as to realize electron pre-resonance stimulated Raman; and a balance detection technology is combined at a detection end, so that high-sensitivity, high-resolution and high-signal-to-noise-ratio detection of stimulated Raman signals is realized.

The invention belongs to the technical field of gas detection, and particularly relates to a multi-component gas detection device and a detection method.The multi-component gas detection device is characterized in that according to components of detected gas, a laser driver drives a laser array to emit light with different modulation frequencies and multiple wavelengths, the light is changed into parallel light after passing through an optical fiber array and a micro-lens array, and the parallel light is transmitted to a gas detector; after gas to be detected is absorbed and reflected by a diffuse reflection surface, reflected light passes through a lens and a dichroscope to be converged, light with long wavelength and light with short wavelength respectively enter photoelectric detectors with corresponding wave bands, the photoelectric detectors convert optical signals into electric signals and filter the electric signals, and the filtered signals to be detected are transmitted into a digital lock-in amplifier to be processed in parallel. And demodulating second harmonics and first harmonics of different gases, and calculating the concentration of each to-be-detected gas through a calculation unit. According to the invention, simultaneous detection of multi-component gas concentration can be realized.

The invention discloses an InGaN red light LED device based on a variable Al component electron barrier layer to enhance a polarization effect and a preparation method thereof. The InGaN red light LED device sequentially comprises a substrate, a low-temperature buffer layer, a high-temperature buffer layer, a non-doped GaN layer, an n-type doped GaN layer, a superlattice layer and / or a low-temperature GaN layer, a quantum well active region, a p-type AlGaN electron barrier layer and a p-type region from bottom to top, wherein the atomic percentage content of Al in the p-type AlGaN electron barrier layer is 22%-30%, and the thickness of the p-type AlGaN electron barrier layer is 5 nm to 15 nm. By controlling the p-type AlGaN electron barrier layer, long-wavelength emission of the low-In-component active region can be achieved, and the problems that a high-In-component active region of an existing long-wavelength InGaN red light LED is poor in crystal quality and difficult to obtain and the like are solved.

The invention discloses an image acquisition method and system for a dual-wavelength circular polarization camera, and the method comprises the steps: setting two independent nanosecond pulse laser sources, and respectively transmitting lasers with different wavelengths; respectively carrying out left-hand circular polarization and right-hand circular polarization treatment on the two lasers; integrating the two nanosecond pulse laser beams subjected to circular polarization treatment into one beam, wherein the two beams are completely overlapped and are coaxial; the integrated nanosecond pulse laser beams are irradiated to a target object, and reflected light is collected through a double-spectrum camera to form two images with different wavelengths; and distributing weights for the image according to the importance of the polarization information, and generating a comprehensive image by adopting an image fusion technology. According to the image acquisition method and system of the dual-wavelength circular polarization camera, two independent nanosecond pulse laser sources are arranged to emit short-wavelength laser and long-wavelength laser respectively, the two beams of laser are subjected to left-handed and right-handed circular polarization processing and then integrated into one beam, and efficient imaging in a complex environment is achieved.

The present invention addresses the problem of providing an improved RpBphP1 mutant and an improved RpPpsR2 mutant in such a manner that the binding and dissociation can be reliably controlled by light irradiation and shielding of near-infrared light. More specifically, the present invention is a proteome comprising two types of proteins that bind to each other under irradiation of near-infrared light, the proteome being a group of RpBphP1 mutants and wild-type RpPpsR2, a group of wild-type RpBphP1 mutants and RpPpsR2 mutants, or a group of RpBphP1 mutants and RpPpsR2 mutants, the binding of the proteome being greater than that of the wild-type RpBphP1 mutants and that of the wild-type RpPpsR2, and the binding of the proteome being less than that of the wild-type RpBphP1 mutants and that of the wild-type RpPpsR2. The binding in a dark place is weak and / or the binding under the irradiation of near-infrared light is strong.

The invention provides a transcendental extreme ultraviolet light source device which comprises a free electron laser main body which comprises an undulator system and an optical resonant cavity. The undulator system comprises a modulation section undulator and a radiation section undulator; the optical resonant cavity comprises resonant cavity reflectors and a dispersion section, and the modulation section undulator, the dispersion section undulator and the radiation section undulator are sequentially arranged in the direction of an electron beam and are all located between the resonant cavity reflectors; the resonant wavelength output by the radiation section undulator is 1 / h of the resonant wavelength of the modulation section undulator, h is the harmonic number, and when the resonant wavelength output by the radiation section undulator is 6-7nm, the radiation wavelength reflected by the resonant cavity is h times of the resonant wavelength output by the radiation section undulator, so that the resonant cavity is prevented from adopting a reflector with the reflection wavelength of 6-7nm. According to the device, the radiation of the target wavelength is output by using harmonic waves, and a reflector with relatively long wavelength and mature technology can be directly used; various accelerators are compatible, the energy efficiency of the accelerators is greatly improved, and power consumption is reduced.

The invention discloses a high-efficiency erbium-ytterbium co-doped fiber laser for long-wavelength peak shifting pumping. The laser is characterized in that pump light enters an active fiber through a pump coupling device; the active optical fiber is doped with erbium ions and ytterbium ions, part of the pump light entering the active optical fiber is absorbed by the ytterbium ions, and part of the pump light entering the active optical fiber is absorbed by the erbium ions; ytterbium ions are transited from a ground state 2F7 / 2 to an excited state 2F5 / 2 energy level, cross relaxation occurs between the ytterbium ions and ground state erbium ions nearby the ytterbium ions, energy is transferred to the erbium ions, and the erbium ions are relaxed to a 4I13 / 2 energy level after transition from 4I15 / 2 to 4I11 / 2 is completed; erbium ions absorb pump light, transition from a ground state 4I15 / 2 to a 4I11 / 2 energy level and then relaxation to a 4I13 / 2 energy level are carried out, the erbium ions of the 4I13 / 2 energy level generate laser gain of 1.5 microns, and when the gain exceeds loss of a laser resonant cavity formed by the first resonant cavity feedback device and the second resonant cavity feedback device, 1.5 microns-band laser oscillation is formed and is output through the second resonant cavity feedback device. The influence of amplified spontaneous emission of ytterbium ions and excited state absorption of erbium ions on the efficiency of the laser is weakened, and the efficiency of the laser is improved.

The invention discloses an optical thin film thickness monitoring device and an optical thin film coating system, and belongs to the technical field of vacuum coating. A workpiece disc of the optical film thickness monitoring device is provided with a monitoring hole group, the monitoring hole group comprises a first through hole, a second through hole and an interval shielding area, and a film coating monitoring piece is arranged in the first through hole; the irradiation light source is used for emitting light signals to the monitoring hole group; the receiving assembly comprises a light converging element and at least two grating monochromators. The actual physical or optical thickness of the thin film can be calculated by monitoring the transmission or reflectivity of multiple wavelengths and combining the dispersion of the material, and the precision is higher than the precision of monitoring the thickness of the single-wavelength thin film. A plurality of grating monochromaters respectively and correspondingly monitor one wavelength, each grating monochromator can freely select the wavelength, the wavelength selection range is wide, and the problems that the monitoring wavelength is changed and the positioning precision deviation is large in the same grating monochromator are solved. According to the invention, the optical film thickness measurement precision in the online monitoring film coating process can be improved, and the film coating success rate is improved.

The present invention relates to a radiative cooling paint consisting of ceramic fine particles as pigments, a polymer resin as a binder, and a solvent. According to the present invention, a substrate is coated with the radiative cooling paint, and then a paint film layer is formed. The paint film layer performs a radiative cooling function by preventing energy inflow from incident sunlight by maximizing reflection of incident sunlight; minimizing absorption of incident sunlight; and maximizing emission of long-wavelength infrared light corresponding to 8 μm to 13 μm and increasing energy discharge through emission of long-wavelength infrared light, and pores with a volume of 3% to 50% are formed inside the paint film layer to enhance reflection of incident sunlight without reducing emission of long-wavelength infrared light.

The invention discloses a preparation method of a composite material for improving the utilization rate of solar blue-green photocatalytic degradation of water pollutants, which comprises the following steps: firstly, preparing a Cu-ZnO nano composite material by doping zinc oxide with copper ions, and reducing the forbidden band width, so that the Cu-ZnO nano composite material can utilize sunlight with longer wavelength, and the absorption peak of the Cu-ZnO nano composite material generates red shift; secondly, decolorizing the wood by adopting an alkaline sodium sulfate method, removing lignin in the wood to leave a cavity, and growing the Cu-ZnO nano composite material in the treated wood and on the surface of the treated wood by adopting a hydrothermal method to form a composite material with a catalyst growing in a similar resonant cavity, as shown in Figure 1; the utilization rate of a semiconductor catalyst to blue-green light is improved, a cavity structure formed by the treated wood can have a certain local effect on long-wavelength light, the purpose of fully utilizing long-wave sunlight for multiple times is achieved, and the blue-green photocatalytic efficiency is improved.

Flow characteristics of a three-dimensional fluid flow are quantified by bubble thermography velocimetry (BTV) in which large numbers of bubbles buoyant in the fluid and having a predetermined size and temperature are introduced into in the fluid flow while long wavelength infrared camera (LWIR) cameras record the positions over time of individual bubbles. In one application the fluid is air and the bubbles are soap bubbles, and the velocity, acceleration and direction of individual bubbles carried by wind through a target area of interest are derived from the position of each bubble at predetermined time intervals for environmental analyses such as weather and climate modeling, urban dispersion studies, building wind load analyses, and the like. BTV defines each bubble's path and velocity vectors in three dimensions that produce richer data than known flow analysis techniques by tracking the bubbles over larger scales at correspondingly higher spatial and velocity resolutions.

A line narrowing gas laser device includes an actuator changing a center wavelength of pulse laser light, and a processor controlling the actuator. The processor reads parameters including a number of irradiation pulses of pulse laser light to be radiated to one location of an irradiation receiving object, a shortest wavelength, and a longest wavelength; sets a first pattern with which the center wavelength is changed to approach the longest wavelength from the shortest wavelength and a second pattern with which the center wavelength is changed to approach the shortest wavelength from the longest wavelength such that at least one of the first pattern and the second pattern when the number of irradiation pulses is an even number is different from corresponding one when the number of irradiation pulses is an odd number; and controls the actuator so that the first pattern and the second pattern are alternately performed.

The invention discloses a short-long wave laser hybrid welding method for aluminum alloy, and belongs to the field of laser welding. The method comprises the following steps: firstly, treating the surface of the aluminum alloy by adopting short-wavelength laser as a pretreatment laser source to enable the surface of the aluminum alloy to be in a molten state; according to the method, aluminum is pre-melted, then long-wavelength laser is adopted for welding, due to the fact that the reflectivity of the aluminum to the infrared laser in the liquid state is remarkably reduced, the pre-melting step creates conditions for follow-up long-wavelength infrared laser welding, the absorption rate of the infrared laser is remarkably improved, and loss of laser energy is reduced; according to the process, the utilization rate of welding energy is optimized and the welding quality is improved by utilizing different heating effects of lasers with different wavelengths on the surface of the aluminum alloy.

The invention discloses a group III nitride two-color resolution detector, an imaging array and an imaging method. The detector comprises a substrate layer, a wide forbidden band layer, a narrow forbidden band layer, an electrode cathode and an electrode anode. The array comprises a plurality of III-nitride two-color resolution detectors which are arranged in parallel. The method comprises the steps that an optical signal enters from the top of the detector, a long wavelength component in the incident light is absorbed in a narrow forbidden band layer, a short wavelength component is sequentially absorbed in the narrow forbidden band layer and a wide forbidden band layer, and the detector works under zero bias voltage or negative bias voltage to generate a negative current signal to be output; the detector works under the positive bias voltage to generate positive current output; and collecting output current signals to obtain imaging results of two different wavelengths. According to the invention, the wavelength selection detection effect and the two-color resolution detection imaging effect can be realized by a single device without filtering. The III-nitride two-color resolution detector, the imaging array and the imaging method can be widely applied to the technical field of photoelectric detection imaging.

The present invention relates to a semiconductor nanoparticle containing an AgAuTe compound comprising Ag, Au, and Te as essential constituent elements. The AgAuTe compound constituting the semiconductor nanoparticle is represented by the following formula. The semiconductor nanoparticle according to the present invention contains 90 atomic% or more of the AgAuTe compound. The semiconductor nanoparticle according to the present invention has an improved light absorption characteristic in the long wavelength range and can suitably support applications in the near-infrared range and the short-wave infrared range. Specifically, the semiconductor nanoparticle according to the present invention has an absorption edge wavelength on the long wavelength side of the absorption spectrum of 1200 nm or greater. AgxAuyTez (In the formula, x, y, and z represent the number of atoms of Ag, Au, and Te, respectively, and 0.25 ≤ z / (x + y) ≤ 1 holds true. In addition, y / (x + y + z) > 0.10 also holds true.)

An optical detection unit according to one embodiment of the present disclosure includes: a first photoelectric converter that photoelectrically converts a wavelength component in a visible light region; a second photoelectric converter that photoelectrically converts a wavelength component in a near-infrared region, the second photoelectric converter being stacked on the first photoelectric converter; and a first wiring layer provided between the first photoelectric converter and the second photoelectric converter, the first wiring layer including one or a plurality of wirings formed with use of a material that transmits a wavelength component in a longer wavelength region than the visible light region, the one or the plurality of wirings being used for reading out charges generated through photoelectric conversion in the first photoelectric converter.

The invention belongs to the technical field of analysis and detection, and particularly relates to a beta-galactosidase response type hemicyanine near-infrared fluorescent probe, a preparation method thereof and application of the beta-galactosidase response type hemicyanine near-infrared fluorescent probe as a tumor organ imaging probe. The near-infrared fluorescent probe provided by the invention takes a water-soluble hemicyanine skeleton as a fluorophore, so that the biocompatibility of the near-infrared fluorescent probe is improved; based on the principle that beta-galactose can be selectively cut by beta-galactosidase, a galactose structure with a self-leaving group is used as a response group, selective quick response to the beta-galactosidase is achieved, and high sensitivity to the beta-galactosidase is shown. The near-infrared fluorescent probe provided by the invention can emit near-infrared fluorescence with long wavelength, has lower background fluorescence and good penetration depth, and can be directly used for detecting organoids containing the matrigel without eliminating the matrigel, so that the organoids are prevented from being damaged or additional experimental variables are prevented from being introduced in the process of eliminating the matrigel.

The present invention discloses a dual-color infrared detector, which comprises a mid-wavelength infrared detector and a long-wavelength infrared detector arranged in a stacked manner. The mid-wave channel absorption layer of the mid-wavelength infrared detector is a P-type InAs / InAsSb superlattice or a P-type InAsP / InAsSb superlattice, the long-wave channel absorption layer of the long-wavelength infrared detector is a P-type InAs / GaSb superlattice, and the mid-wave channel barrier layer of the mid-wavelength infrared detector and the long-wave channel barrier layer of the long-wavelength infrared detector are both N-type InPSb / InAs superlattices. The present invention also discloses a manufacturing method of the dual-color infrared detector. The mid-wave channel absorption layer of the dual-color infrared detector of the present invention adopts an InAs / InAsSb or InAsP / InAsSb superlattice, and the long-wave channel absorption layer adopts an InAs / GaSb superlattice, thus ensuring the best performance of the devices in each waveband.

The invention discloses a method for improving the solving speed of a rotating sphere non-singularity electromagnetic scattering field, and belongs to the field of electromagnetic engineering. Aiming at the electromagnetic scattering problem of a rotating structural body in the field of practical engineering, the invention provides a method for improving the non-singularity electromagnetic scattering field solving speed of a rotating body, and effective analysis of the rotating body is realized based on a moment method. A rotating structure body has important application value in electromagnetic radiation and scattering research due to geometric symmetry, but under the condition of long wavelength, a traditional surface integration method often has the problem of singularity, and numerical stability and precision are affected. Therefore, a method for effectively eliminating singular integrality and converting a dense matrix needing to be solved into a sparse matrix is designed, the calculation efficiency is remarkably improved, and the memory consumption is reduced. A non-singularity surface integral equation is obtained through derivation, simulation and numerical simulation are carried out through a specific electromagnetic rotating body device model, an efficient numerical solution is provided for the electromagnetic scattering problem, and the method has wide engineering application prospects.

To provide a laser assembly that injects a laser beam on a long-wavelength side, and a laser module capable of suppressing deterioration of an output efficiency.SOLUTION: A laser module 100 at least comprises: a housing 110; a base 10 housed in an internal part of them; and a plurality of layer assembling bodies 40. Each assembling body 40 includes a laser diode bar 43. A wavelength of a laser beam LB injected from each of a plurality of laser diode bars 43 is different each other. In an inner side of the base 10, a cooling channel 11 having an inflow entrance 11A and an outflow entrance 11B of a cooling water is provided. Each assembling body 40 is arranged onto an upper surface of the base 10 that is arranged with an interval so as to be along a long direction of the cooling channel 11. A wavelength of a plurality of laser beam LB becomes shorter as far from the inflow entrance 11A.SELECTED DRAWING: Figure 2

An LED includes first / second doped layers with active region(s) therebetween emitting a first wavelength. A wavelength converter on a first LED surface absorbs the first wavelength and emits a second, longer wavelength. A second LED surface is against a substrate surface. A first electrical contact on the first LED surface extends along LED sidewalls, separated from the active region(s) and second doped layer by an insulating layer, connecting the first doped layer to a first contact pad. In some instances, contact pads are on the substrate surface; a second electrical contact extends onto LED sidewalls, connecting the second doped layer to a second contact pad. In some other instances contact pads are on laterally-extending portions of the second doped layer. The insulating layer separates the first contact pad from the second doped layer; a second contact pad is in direct electrical contact with the second doped layer.

The invention discloses a display device with an active red light function and application thereof, and belongs to the technical field of display. Comprising a backlight unit; the backlight unit comprises a light guide plate and a light source; the light source comprises a red light source and a blue light source; the light source is located on the lower side of the diffusion plate or located on at least one side of the periphery of the light guide plate. A quantum dot yellow film, a first prism film, a second prism film, a DBEF brightness enhancement film, a diffusion film and a liquid crystal panel are sequentially arranged on the upper side of the diffusion plate or the light guide plate from bottom to top in a stacked mode. When the display device is applied, the white light mode is used for conventional use, the quantum dot yellow film is used for converting blue LED backlight, high-purity green light and eye protection red light with the long wavelength of 650 nm are emitted, the blue light content in the display device can be remarkably reduced, the display color gamut can be improved, and the eye use comfort degree can be improved. In the red light mode, the display device is used for emitting high-intensity long-wavelength 650nm eye protection red light, so that the beneficial effects of preventing and controlling myopia and protecting eye health are achieved.

A method and system including: an aerial vehicle including: a first camera comprising a first sensor having at least red, green, and blue color channels, where the blue color channel is sensitive to near-infrared (NIR) wavelengths; a first optical filter disposed in front of the first sensor, wherein the first optical filter is configured to block wavelengths below green, between red and NIR, and longer wavelength NIR; a processor having addressable memory in communication with the first camera, where the processor is configured to: capture at least one image of vegetation from the first camera; provide red, green, and NIR color channels from the captured image from the first camera; and determine at least one vegetative index based on the provided red, green, and NIR color channels.

The invention discloses a perovskite narrow-band photoelectric detector based on local plasma enhancement and a preparation method thereof, and the perovskite narrow-band photoelectric detector utilizes specially-made metal nanoparticles to accurately adjust a local surface plasma resonance band of the perovskite narrow-band photoelectric detector, thereby achieving the purpose of overlapping with a perovskite target narrow-band response range. Therefore, penetrating long-wavelength incident photons and an electromagnetic field around the metal nanoparticles generate strong coupling interaction, light absorption is effectively improved through a near-field enhancement induction excitation effect, light current is remarkably enhanced, a local surface plasmon resonance band is regulated and controlled, harmonious enhancement of a detection wave band is achieved, and the detection sensitivity is improved. And the detection performance regulation and control enhancement in the spectral response range of the photoelectric detector is further realized.

A laser device includes a first actuator configured to adjust an oscillation wavelength of pulse laser light; a second actuator configured to adjust a spectral line width of the pulse laser light; and a processor configured to determine a target spectral line width by reading data specifying a number of irradiation pulses of the pulse laser light with which one location of an irradiation receiving object is irradiated and a difference between a shortest wavelength and a longest wavelength, control the second actuator based on the target spectral line width, and control the first actuator so that the oscillation wavelength periodically changes every number of the irradiation pulses between the shortest wavelength and the longest wavelength.