This PDF file contains the front matter associated with SPIE Proceedings Volume 10085, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and Conference Committee listing.

The lateral beam parameter product, BPP_lat, and resulting lateral brightness of GaAs-based high-power broad-area diode lasers is strongly influenced by the thermal lens profile. We present latest progress in efforts using FEM simulation to interpret how variation in chip construction influences the thermal lens profile, itself determined experimentally using thermography (thermal camera). Important factors are shown to include the vertical (epitaxial) structure, the properties of the submount and the transition between chip and submount, whose behavior is shown to be consistent with the presence of a significant thermal barrier.

High power diode lasers have been widely used in many fields. To meet the requirements of high power and high reliability, passively cooled single bar CS-packaged diode lasers must be robust to withstand thermal fatigue and operate long lifetime. In this work, a novel complete indium-free double-side cooling technology has been applied to package passively cooled high power diode lasers. Thermal behavior of hard solder CS-package diode lasers with different packaging structures was simulated and analyzed. Based on these results, the device structure and packaging process of double-side cooled CS-packaged diode lasers were optimized. A series of CW 200W 940nm high power diode lasers were developed and fabricated using hard solder bonding technology. The performance of the CW 200W 940nm high power diode lasers, such as output power, spectrum, thermal resistance, near field, far field, smile, lifetime, etc., is characterized and analyzed.

Narrow linewidth tunable diode lasers are an important tool for spectroscopic instrumentation. Conventional external cavity diode lasers are designed as laboratory instrument and do not allow hand-held operation for portable instruments. A new miniaturized type of tunable external cavity tunable diode laser will be presented. The presentation will focus on requirements on the assembly technology of micro-optic components as well as on the physical properties of such devices. Examples for the realization of this new technology will be given in the NIR for Alkaline Spectroscopy as well as in the MIR at 1908nm.

In this work, a fiber-coupled diode laser module emitting around 1116 nm with an output power P < 60 mW is realized. As a laser light source a distributed Bragg reflector (DBR) ridge waveguide diode laser is applied. The module comprises temperature stabilizing components, a micro-lens system as well as an optical micro-isolator. At the output, a polarization-maintaining single-mode fiber (PM-SMF) with a core diameter of 5.5 μm and a standard FC/APC connector are utilized. The generated diffraction limited beam is characterized by a narrow linewidth ( δν < 10 MHz) and a high polarization extinction ratio (PER > 25 dB).

Packaging solutions developed for Luxmux's BeST SLED family of sources will be discussed along with their applications. In particular, a narrow linewidth (<300 pm) continuously tunable (from 1250 nm to 1750 nm) laser source providing >20mW output power from a compact fiber-coupled butterfly package will be presented.

A new tool based on artificial neural networks to assist in the accurate positioning of the lenses used to collimate the beams emitted by the individual chips forming multi-emitter diode laser modules is presented. Then, a new expression for the evaluation of the obtained beam quality is disclosed and the impact of different choices on the overall module performance in terms of beam quality and coupling efficiency into a collecting fiber is analyzed. Experimental validations with different combinations of lenses are reported to prove the effectiveness of the proposed approach.

We present performance and reliability data of high-brightness QCW arrays and stacks with a custom, compact and robust design for an operation at high duty cycles. The presented designs are based on single diodes consisting of a 10mm laser bar which is AuSn soldered between two WCu submounts, as well as 10mm laser bars AuSn soldered to WCu submounts or Indium directly mounted to micro channel heat sinks. The available optical output strongly depends on the wavelength and fill factor of the laser bars as well as the duty cycle, the base plate temperature and the thermal performance to handle the thermal loss. Based on the applications requirements, conduction cooled stacks can be used in conjunction with thermo-electric coolers, water manifolds, or forced air cooling. For most demanding requirements at highest peak power and duty cycle, micro channel coolers with conditioned DI water offer the best cooling performance.

Thermal management is one of the most important factors affecting the performance of high power diode lasers. In this paper, transient thermal behavior of conduction-cooled high power diode lasers has been studied using finite element method. The effects of heat sink geometry, ceramics size on the junction temperature of high power diode laser packages have been analyzed. Based on the simulations, heat dissipation capability of high power diode laser packages is improved and compact conduction-cooled diode laser array packages with 3 bars and 5 bars are fabricated. The power ~ current and spectrum of the optimized high power diode laser array packages at different operation parameters are characterized at different pulse widths, repetition frequencies and TEC temperatures. The effects of temperature on the output power and spectrum are discussed. The lifetime test of high power diode laser array packages is also performed. It shows that the conduction-cooled high power diode laser array packages have good optical performance.

Similar to the well-established high power laser diodes in the infrared wavelength range, the laser diodes in the blue wavelength range require tailored optics for beam shaping, to make the light usable for a variety of applications. High power laser diode arrays or single emitters require fast and slow axis optical collimation for further transport or photonics applications using high power laser radiation. With increasing requirements in higher brightness for slow axis collimation different engineering solutions exist. By using novel production technologies, e.g. precision molding, approaches that were considered too expensive for mass production become available to broad application fields. Here we report about the benefits of molded refractive, freeform slow axis collimation optics and compare them to the ubiquitous standard circular cylindrical, as well as acircular cylindrical slow axis collimation optics. By using refractive free form slow axis collimation optics it is possible to achieve significantly better brightness compared to circular cylindrical or acircular cylindrical slow axis collimation optics.

Optical and mechanical aspects of packaging single photon avalanche diodes for different applications will be discussed. Particular emphasis will be given to fiber coupling at high photon detection efficiencies over a wide wavelength range.

To reduce the diode laser bar’s smile effect induced by packaging, a method based on a chip mounter is presented. When the bare bar is picked up by the pick-up tool (PUT) of the chip mounter, the curve direction and volume of the bar can be measured by scanning the P side surface of the bar with a laser rangefinder, and they can be controlled through adjusting the setting up of the PUT. By controlling the curve direction and volume at an appropriate state to compensate the packaging induced strain, the obtaining smile effect is restricted within 0.5μm steadily.

Laser systems face massive economic challenges for cost effective, but yet ultraprecise assembly processes. Costs are mainly driven by the final assembly requirements of laser systems. Most challenging in this context is the robust process control of the UV-curing adhesive bonding process. The work presented aims for a significant reduction of the impact of shrinkage effects during curing and a resulting increase in assembly precision. Key approaches are integrated and characterized curing systems, ultraprecise dispensing processes and the automated characterization of adhesive shrinkage magnitude. These technologies allow for reproducible adhesive bonding processes in prototyping, job-shop assembly and automated assembly cells.

We present the status of our efforts to develop very compact and robust diode laser modules specifically suited for quantum optics experiments in the field and in space. The paper describes why hybrid micro-integration and GaAs-diode laser technology is best suited to meet the needs of such applications. The electro-optical performance achieved with hybrid micro-integrated, medium linewidth, high power distributed-feedback master-oscillator-power-amplifier modules and with medium power, narrow linewidth extended cavity diode lasers emitting at 767 nm and 780 nm are briefly described and the status of space relevant stress tests and space heritage is summarized. We also describe the performance of an ECDL operating at 1070 nm. Further, a novel and versatile technology platform is introduced that allows for integration of any type of laser system or electro-optical module that can be constructed from two GaAs chips. This facilitates, for the first time, hybrid micro-integration, e.g. of extended cavity diode laser master-oscillator-poweramplifier modules, of dual-stage optical amplifiers, or of lasers with integrated, chip-based phase modulator. As an example we describe the implementation of an ECDL-MOPA designed for experiments on ultra-cold rubidium and potassium atoms on board a sounding rocket and give basic performance parameters.

One important aspect for the increasing use of diode lasers in industrial applications is the flexibility of diode lasers to tailor the beam properties to the specific needs demanded from the application. For fiber coupled solutions beam shaping with appropriate micro-optical elements is used for efficient fiber coupling of the highly asymmetric diode laser beam, whereas for direct applications optical elements are used to generate specific intensity distributions, like homogenized lines, areas and rings. Applications with diode lasers like solid state laser pump sources often require tailored spectral characteristics with narrow bandwidth, which is realized by using volume Bragg gratings for wavelength stabilization.

In this paper we will summarize several concepts for adapting beam properties of diode lasers by using specific optical components. For building very compact laser modules of up to 2 kW we already presented a concept based on beam shaping of high fill factor bars. In this paper we will focus on further tailoring the beam properties of these very compact laser modules in the wavelength range from 808 nm up to 1020 nm. Fiber coupling of such modules into an 800 μm NA0.22 fiber yielded 1.6 kW without using polarization coupling. Another example is the generation of a 2.5 kW homogenized line with 40 mm length and a width of 4 mm.

Wideband emission spectra of laser diode bars (several nanometers) can be largely narrowed by the usage of thick volume Bragg gratings (VBGs) recorded in photo-thermo-refractive glass. Such narrowband systems, with GHz-wide emission spectra, found broad applications for Diode Pumped Alkali vapor Lasers, optically pumped rare gas metastable lasers, Spin Exchange Optical Pumping, atom cooling, etc.

Although the majority of current applications of narrow line diode lasers require CW operation, there are a variety of fields where operation in a different pulse mode regime is necessary. Commercial electric pulse generators can provide arbitrary current pulse profiles (sinusoidal, rectangular, triangular and their combinations). The pulse duration and repetition rate however, have an influence on the laser diode temperature, and therefore, the emitting wavelength. Thus, a detailed analysis is needed to understand the correspondence between the optical pulse profiles from a diode laser and the current pulse profiles; how the pulse profile and duty cycle affects the laser performance (e.g. the wavelength stability, signal to noise ratio, power stability etc.). We present the results of detailed studies of the narrowband laser diode performance operating in different temporal regimes with arbitrary pulse profiles. The developed narrowband (16 pm) tunable laser systems at 795 nm are capable of operating in different pulse regimes while keeping the linewidth, wavelength, and signal-to-noise ratio (>20 dB) similar to the corresponding CW modules.

High power diode laser arrays have found increasing applications in the field of pumping solid-state lasers and fiber lasers. Due to the thermal crosstalk across diode laser arrays and non-uniformity of local flow rate within microchannel cooler, junction temperature distribution becomes inhomogeneous, consequently leading to spectrum broadening and large beam divergence of diode laser pumping sources. In this work, an analytical method and numerical heat transfer based on finite volume method were employed to optimize the inner structure of microchannel cooler so as to obtain low thermal resistance and uniform junction temperature distribution for the diode laser arrays. Three-dimensional numerical models were developed to study the fluid flow and heat transfer of copper stacked microchannel coolers with different dimensions and arrangements of inner channels and fins. More uniform junction temperature distribution of diode laser array package could be achieved by self-heating compensation with specific coolant covering width. These results could provide significant guidance for the design of microchannel coolers of high power diode laser arrays for better performance.

Today, the use of laser photons for materials processing is a key technology in nearly all industries. Most of the applications use circular beam shapes with Gaussian intensity distribution that is given by the resonator of the laser or by the power delivery via optical fibre. These beam shapes can be typically used for material removal with cutting or drilling and for selective removal of material layers with ablation processes. In addition to the removal of materials, it is possible to modify and improve the material properties in case the dose of laser photons and the resulting light-material interaction addresses a defined window of energy and dwell-time. These process windows have typically dwell-times between µs and s because of using sintering, melting, thermal diffusion or photon induced chemical and physical reaction mechanisms. Using beam shaping technologies the laser beam profiles can be adapted to the material properties and time-temperature and the space-temperature envelopes can be modified to enable selective annealing or crystallization of layers or surfaces. Especially the control of the process energy inside the beam and at its edges opens a large area of laser applications that can be addressed only with an optimized spatial and angular beam profile with down to sub-percent intensity variation used in e.g. immersion lithography tools with ArF laser sources. LIMO will present examples for new beam shapes and related material refinement processes even on large surfaces and give an overview about new mechanisms in laser material processing for current and coming industrial applications.

Modern multimode high-power lasers are widely used in industrial applications and control of their radiation, especially by focusing, is of great importance. Because of relatively low optical quality, characterized by high values of specifications Beam Parameter Product (BPP) or M², the depth of field by focusing of multimode laser radiation is narrow. At the same time laser technologies like deep penetration welding, cutting of thick metal sheets get benefits from elongated depth of field in area of focal plane, therefore increasing of zone along optical axis with minimized spot size is important technical task. As a solution it is suggested to apply refractive optical systems splitting an initial laser beam into several beamlets, which are focused in different foci separated along optical axis with providing reliable control of energy portions in each separate focus, independently of beam size or mode structure. With the multi-focus optics, the length of zone of material processing along optical axis is defined rather by distances between separate foci, which are determined by optical design of the optics and can be chosen according to requirements of a particular laser technology. Due to stability of the distances between foci there is provided stability of a technology process. This paper describes some design features of refractive multi-focus optics, examples of real implementations and experimental results will be presented as well.

Potassium terbium fluoride is a recently developed magneto-optic material which has been proposed for use as an optical isolator. We have performed measurements of the refractive index, thermo-optic coefficient, and stress-optic coefficient of this material. We present a temperature dependent Sellmeier equation along with calculations of temperature and refractive index profiles at various pump power levels in a diode pumped laser. The data are critical to the design of laser systems in which optical isolators are employed.

We report on a ruggedized compact modular package narrow linewidth fiber amplifiers with 1.5kW linear polarized output in an all-PM fiber configuration and 2 kW in non-PM fiber configuration for various scientific and advanced applications. The fiber amplifiers have 2m output cable with connector termination for 15GHz linewidth and 20GHz linewidth in PM and in non-PM fiber configuration respectively. The fiber amplifiers have 40% wall-plug efficiency and 15nm spectral bandwidth for 1064nm wavelength range. Measured M² values of the output beam of the amplifiers are < 1.1.

A CW kilowatt fiber laser numerical model has been developed taking into account intracavity stimulated Raman scattering (SRS). It uses the split-step Fourier method which is applied iteratively over several cavity round trips. The gain distribution is re-evaluated after each iteration with a standard CW model using an effective FBG reflectivity that quantifies the non-linear spectral leakage. This model explains why spectrally narrow output couplers produce more SRS than wider FBGs, as recently reported by other authors, and constitute a powerful tool to design optimized and innovative fiber components to push back the onset of SRS for a given fiber core diameter.

Issue of frequency-to-amplitude modulation (FM-to-AM) conversion is one of the key scientific problems in the development of high power lasers, especially in fusion laser drivers. In large aperture and high power lasers, the sinusoidal phase modulated pulses are used to avoid stimulated Brillouin scattering and to obtain spatially-averaged focal spot on the target. Propagation through optical components in the laser chains is not optimal and slightly filters the parts of the optical spectrum. Therefore, the frequency modulation (FM) is partly converted into the amplitude modulation (AM), and this AM will lead to higher-order nonlinear effects or even cause damages to optical elements due to instantaneous ultrahigh intensity in laser propagation process.

Volume Bragg gratings (VBGs) with programmable angular selectivity from 0.1mrad to 10mrad and high efficiency of 99 % is an effective filtering element to clean up the spatial modulations in laser beams. The FM-to-AM conversion is studied with a sinusoidal phase modulation laser pulse with the bandwidth of 0.30nm and 0.15nm, and is demonstrated with an YLF laser with the wavelength of 1053 nm and pulse width of 3ns. The experimental results show that FM to AM conversion level is increasing with the decrease of the spectrum selectivity bandwidth of the VBGs. At the VBG spectrum selectivity bandwidth of 7.9 nm, the FM to AM conversion level is reduced to about 6% for 0.3 nm and 3.5% for 0.15nm, which can be used in high power laser for controlling the beam spot on the target.

Planar holographic optical elements (volume Bragg gratings, VBGs) recorded in photo-thermo-refractive (PTR) glass are widely used for fine spectral filtering and laser beam control. PTR glass provides photosensitivity in near UV region. Therefore, while planar holographic elements operate in the whole window of transparency - near UV, visible and near IR spectral regions, application of complex (nonplanar) elements is restricted to near UV. A method has been proposed to create high-efficiency diffractive optical elements in PTR glass using visible light. The method employs excited state absorption in PTR glass doped with Tb³⁺. UV radiation was used for excitation to a metastable level of Tb³⁺ and pulsed radiation at 532 nm was used for hologram recording. Both planar VBGs and holographic lenses operating at 532 nm were demonstrated. Complex holographic optical elements in PTR glass can provide attractive solutions for lasers and spectroscopy replacing conventional optical components.

Cold atom interferometers are emerging as important tools for metrology. Designed into gravimeters they can measure extremely small changes in the local gravitational field strength and be used for underground surveying to detect buried utilities, mineshafts and sinkholes prior to civil works. To create a cold atom interferometer narrow linewidth, frequency stabilised lasers are required to cool the atoms and to setup and measure the atom interferometer. These lasers are commonly either GaAs diodes, Ti Sapphire lasers or frequency doubled InGaAsP diodes and fibre lasers. The InGaAsP DFB lasers are attractive because they are very reliable, mass-produced, frequency controlled by injection current and simply amplified to high powers with fibre amplifiers. In this paper a laser system suitable for Rb atom cooling, based on a 1560nm DFB laser and erbium doped fibre amplifier, is described. The laser output is frequency doubled with fibre coupled periodically poled LiNbO3 to a wavelength of 780nm. The output power exceeds 1 W at 780nm. The laser is stabilised at 1560nm against a fibre Bragg resonator that is passively temperature compensated. Frequency tuning over a range of 1 GHz is achieved by locking the laser to sidebands of the resonator that are generated by a phase modulator. This laser design is attractive for field deployable rugged systems because it uses all fibre coupled components with long term proven reliability.

With the increased adoption of high power fiber laser for various industrial applications, the downtime and the reliability of fiber lasers become more and more important. Here we present our approach toward a more reliable and more intelligent laser source for industrial applications: the SMAT fiber laser with the extensive sensor network and multi-level protection mechanism, the mobile connection and the mobile App, and the Smart Cloud. The proposed framework is the first IoT (Internet of Things) approach integrated in an industrial laser not only prolongs the reliability of an industrial laser but open up enormous potential for value-adding services by gathering and analyzing the Big data from the connected SMAT lasers.

We present an environmentally stable Yb ultrafast ring oscillator utilizing a new method of passive mode-locking. The laser is using all-fiber architecture which makes it insensitive to environmental factors, like temperature, humidity, vibrations, and shocks. The new method of mode-locking is utilizing crossed bandpass transmittance filters in ring architecture to discriminate against CW lasing. Broadband pulse evolves from cavity noise under amplification, after passing each filter, causing strong spectral broadening. The laser is self-starting. It generates transform limited spectrally flat pulses of 1 – 50 nm width at 6 – 15 MHz repetition rate and pulse energy 0.2 – 15 nJ at 1010 – 1080 nm CWL.

Chirped Bragg Gratings (CBGs) in photo-thermo-refractive (PTR) glass allow stretching and compression of ultra-short pulses with high pulse energy and power and minimal beam distortions. PTR glass based CBGs can stretch pulses up to 1 ns while the duration of the recompressed pulses is nearly transform limited. Recent advances in the technology of CBGs in PTR glass enabled fabrication of chirped gratings with diffraction efficiencies exceeding 95% that allows their usage as intracavity elements. In this paper we discuss properties of Nd:Yag laser with CBGs used as output couplers.

We have developed a packaged fiber amplifier configuration that allows for nearly two orders of magnitude of pulse width adjustment from 1ns to >800ns. This has been developed for both the 1-micron and 1.55-micron spectral regions. Our 1.55-micron fiber laser is packaged into a 6.63 x 8.65 x 3.47 in3 box, while our 1-micron fiber laser is packaged into a 13.68 x 8.68 x 3.56 in3 box, with the larger package a result of larger fiber components. These lasers offer a wide range of adjustable operating points, with total output ultimately limited by available pump power. For 1ns pulses, our 1.55-micron system generates up to 6μJ of pulse energy (>6kW peak) with transform-limited spectral output. Higher energies and output powers are achievable (up to 33μJ at 25kW peak), but the spectral output broadens slightly due to nonlinearities with <5ns pulse durations. For 1ns pulses at 1-micron, the system can generate 10uJ pulse energy (>10kW peak) with high spectral purity. At >10ns pulse durations, the same laser can generate up to 40μJ pulse energy (pump limited). A unique aspect of our design is that a single fiber laser package can be electrically adjusted to produce the full range of pulse widths at repetition rates ranging from 100kHz to <1MHz with well-behaved output pulse shapes and no rising-edge pulse distortions typically seen in high gain amplifiers. In this paper, we discuss our laser architecture, performance, packaging layout, packaging limitations, and a path toward more compact designs using standard fiber components.

We report a novel diffractive beam splitter designed for use in parallel laser processing with two different wavelengths. This element generates two beam arrays of the two wavelengths and enables their overlap at the process points on a workpiece. To design the deep surface-relief profile of a splitter using a simulated annealing method, we introduce a heuristic but practical scheme to determine the maximum height and the number of quantization levels. The designed corrugations were formed in photoresist by maskless grayscale exposure using a high-resolution spatial light modulator. We evaluated the optical properties of the resist splitter, thereby validating the proposed beam delivery concept.

The uniform near-field distribution and focusing characteristics of laser beam, which is related with the spatial frequencies in laser beams, are very important for high power laser applications, such as laser processing and laser fusion. The traditional pinhole filter can be used to improve the near-field uniformity, but may lead to the pinhole-closure and back-reflection. The angular filter based on transmitting volume Bragg gratings (TBGs) recorded in the photo-thermorefractive (PTR) glass could be used to improve the near-field beam quality. However, the incident beam must satisfy the Bragg condition and the optical axis of filtered beam is deflected, which makes the laser system very difficult to align. The band-stop angular filter with two TBGs may be a good method to solve the above problems.

In this paper, the band-stop angular filtering is performed and characterized. The band-stop angular filtering is demonstrated with a YLF laser with the wavelength of 1053 nm. The TBGs used in the experiment has the angular selectivity of 1.35mrad, the period of 1.97μm and the diffraction efficiencies of about 92%. Since part of the characteristic spatial frequencies was cleared out with the band-stop angular filter, there was an intensity drop on the edge of the filtered beam. The optical axis for the incident and output beams keeps basically coaxial after filtering, which can be used as a plug-and-play device in the high-power laser systems. The characteristic spatial frequency of 1.98mm-1 corresponds to the TBG deviation angle of 1.35mrad, and the spatial frequencies around the characteristic frequency of 1.98mm-1 were reduced to 20% compared to that of the original beam. The desired bands in the laser beam can be filtered with different TBGs, which has potential applications in high power lasers.

New applications with 3D sensing technologies are entering the market every day. Based on diffractive optical elements, structured light is a key factor to realize computer vision based sensing solutions. Active alignment can compensate uncertain tolerances during early stages of the product development, which eases prototyping and ramp up of production. Built upon a customizable micromanipulator design, a specialized part handling system with integrated measurement and UV curing capabilities has been designed. We will discuss our production solution and alignment algorithm and present how it can be scaled for high volume production.

In this study, we propose a laser beam pointing method that allows for simultaneous control of position and angle using two commercially available galvanometer mirrors. Two mirrors are placed next to each other. Mathematical calculations show that the outgoing beam angle for the system is defined by the control angles of the two mirrors, and the one-dimensional position of the outgoing beam is defined by the angles of the two mirrors and the distance between their rotational centers. Using a line laser, two galvanometer mirrors, and a camera, we confirmed that the one-dimensional position and angle can be controlled using the proposed method. This method can be used for dynamic fabrication and manufacturing in future.

Photonic crystal spatial filters is a potential solution to suppress multimode operation in micro-cavity lasers increasing the output beam spatial quality and its brightness. Here we propose that the operation of such PhCs can be improved by solving the inverse design problem with the use of chirped structure seed configuration without performing costly global searches. We experimentally prove the feasibility of such method by fabricating the PhC filters in Foturan photosensitive glass, opening new opportunities for photonic integration. The improvement goes beyond earlier achievements by factor of two for different desired lengths of the crystal.

We discuss implementation of the combined node scanning SRS lidar system for high-speed and high spatial resolution (about 3 cm) scanning in wide and narrow angle at a distance of 50-100 m. Narrowband scanning is performed by the deflector moving along a spiral path. Rotating angle wedges of the deflector deviate a beam by an angle of ± 50. This design constitutes an "optical reduction" wedge between the steering angle and the deflection angle of the optical axis and allows 15 ' positioning accuracy. overview of the entire study area for no more than 1 ms at a frequency of rotation of each of the wedges of 50-200 Hz. Unambiguous definition of the geographical coordinates of the probed object is achieved by using high-precision GPS-module and the Vincenty's algorithms. It allows to build a 3D spatial distribution of concentrations of air pollutants.

A longitudinally excited CO₂ laser driven with a reverse recovery characteristics of high voltage diode has been developed. A diode is used to control the high voltage pulse as an opening switch. Power supply for longitudinally excited CO₂ laser is composed of a pulse generator, transformer, capacitor, and a diode, is very simple. Laser oscillation has been successfully achieved, several tens of mJ in laser energy has been obtained.

We numerically designed the cladding pump light stripper with optimized parameters, the design slowly scattered the power in 2.3cm length and the structure shows a constant temperature in the cladding pump stripper region. We next fabricated the light stripper using a CO₂ laser system. In the experiment, we demonstrated the stripping of 60W power from the cladding region, and the structure shows 30°C of constant temperature.