- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Study on Features of 532nm Laser as Laser Source of Lidar
摘要： The laser source of Lidar usually uses the high power solid laser, the performance of Lidar depends on the laser features, so that to study the laser features is contribute to optimizing the performance of Lidar. Set up and design a pulse solid laser of Nd3+:YAG as the working substance. Through adopting the KTP crystal frequency multiplication technology outside the laser cavity and electro-optic q-switch technique, the maximum dynamic pulse energy of 155mJ and pulse width of 9.6 ns with the 532nm laser is generated. Using the oscilloscope, photoelectric pulse sensor and laser energy meter to measurement the experimental data of the laser source features Through analyze and discuss the experimental data, the relationship between the pulse width, the static and dynamic ratio, the peak power of the pulse Nd3+:YAG laser, the frequency doubling efficiency of the KTP crystal and the input power of laser are given, the solid laser system and the experimental data can provide a basic equipment and reference data to the further study.
关键词： 532nm laser,High power,Laser tracking system,Nd3+:YAG laser
更新于2025-09-16 10:30:52
-
Analysis of the Source Type Influence on the Structure Forming during Aluminum Wire-Feed Laser Deposition
摘要： Most of the enterprises around the world engaged in various industrial sectors appreciated the potential of additive technologies. One such technology is direct laser deposition. The technology of direct laser deposition is most relevant for the manufacture and restoration of parts due to lower time and resource costs compared to traditional technologies. The use of wire instead of powder can reduce the consumption of filler material and improve production efficiency. The article presents the results of the study of the additive technology of direct deposition from aluminum wire using various energy sources - laser, arc, and combined laser-arc. Also presented grown samples obtained by each method. Metallographic studies were carried out to study the structure of grown samples from the aluminum alloy AlMg6Zr. Experimental work was carried out on a technological complex based on an ytterbium fiber laser with a power of up to 16 kW (LS-16) and an arc source for MIG welding.
关键词： high power laser,microstructure aluminum based alloys,laser cladding
更新于2025-09-16 10:30:52
-
Characteristics of quasi-unipolar electromagnetic pulses formed in the interaction of high-power laser pulses with nanoscale targets
摘要： A new method is suggested for generating quasi-unipolar electromagnetic IR and terahertz pulses. The method is based on synchronous acceleration of electrons combined to a dense bunch with a charge of up to several tens nanocoulombs, which are forced out from a nanoscale target under an action of a high-power, sharp-leading edge laser pulse. The electromagnetic bunch moving in a field of laser radiation can generate high-power electromagnetic pulses with various spectral composition including terahertz and IR ranges. A physical mechanism underlying the formation of generated quasi-unipolar pulses of electromagnetic radiation is determined and numerically studied. The pulse characteristics are found by numerical simulation, such as amplitude and duration dependences on the angle between the pulse propagation direction and laser beam axis. It is established that in modern laser installations, the amplitudes of quasi-unipolar pulses may reach relativistic values. Reflection of a unipolar pulse from an ideally reflecting surface is numerically analysed. It is shown that the pulse retains its unipolar profile in this case.
关键词： nanoscale targets,generation of terahertz and IR radiation,interaction of high-power laser pulses with matter,electron acceleration by laser pulses
更新于2025-09-16 10:30:52
-
Thermo-elastic stress in high-power laser bars
摘要： This article presents the results of three-dimensional modeling of thermo-elastic stresses arising during the operation of a powerful laser diode bars mounted on a CuW thermal compensator using AuSn soldering alloy in a wide range of thermal loads up to extreme values. Calculated distributions of thermo-elastic stresses at the output and highly reflective mirror of the laser bar is compared. An interpretation of the results obtained, in particular, higher values of thermo-elastic stresses on a less hot highly reflective mirror, in comparison with a hotter output mirror, is proposed.
关键词： thermal loads,three-dimensional modeling,thermo-elastic stress,laser diode bars,high-power laser bars
更新于2025-09-16 10:30:52
-
Experimental and numerical study on the influence of the laser hybrid parameters in partial penetration welding on the solidification cracking in the weld root
摘要： The aim of the present study is to investigate the influence of the laser hybrid welding parameters on the solidification cracks in the weld root for partial penetration welding. Welding trials were performed on thick-walled high-strength steels of grade S690QL under the same critical restraint intensity, with a variation of the welding velocity, wire feeding rate, and the focal position of the laser beam. It was ascertained that the welding velocity has a high impact on the solidification cracking phenomenon. A decrease in the welding speed leads to a reduction of the number of cracks in the weld root. The arc power has also a slight influence on the solidification cracking, while the change of the focal position of the laser beam shows also a remarkable effect. Besides, numerical simulation was performed to understand the thermomechanical behavior of the welds for different welding parameters to assist the interpretation of the experimental results.
关键词： Thick-walled steels,Solidification cracking,High-power laser beam,Partial penetration,Laser hybrid welding
更新于2025-09-16 10:30:52
-
The conversion from a Gaussian-like beam to a flat-top beam in the laser hardening processing using a fiber coupled diode laser source
摘要： In this paper, a laser beam from a fiber coupled diode laser source is converted from a Gaussian-like distribution to a flat-top distribution using a set of homogenization optical system, which makes this diode laser source more favorable for laser hardening. Employing this diode laser source, hardening experiments are performed on 35CrMo metal steel. By optimizing parameters of the hardening processing, at the scanning speed of 1100 mm/min and laser power of 1940 W, a Rockwell hardness of 57 HRC and a hardened depth of 1.6 mm are achieved. Experimental results demonstrate the processing ability of this diode laser source in the industrial laser hardening.
关键词： High power,Laser hardening,Homogeneity,Diode laser
更新于2025-09-16 10:30:52
-
Ultra clean manufacturing techniques for final optics assembly in high-power laser facility
摘要： Cleanliness control is one of the most important processes for final optics assembly (FOA) in high-power laser systems. In this paper, an "Ultra Clean Manufacturing (UCM)" concept is put forward for the first time to satisfy the cleanliness requirements for FOA. First, the challenges and requirements for cleanliness in FOA are introduced and the concept of UCM is proposed. Significant surface cleaning technologies for mechanical parts and optics are then expounded. Finally, surface cleanliness control techniques, such as "gas knife" and "laser cleaning", are developed as online cleaning methods for the surface cleanliness in FOA.
关键词： high-power laser facility,cleanness control,contamination,Ultra-clean manufacturing,final optics assembly
更新于2025-09-16 10:30:52
-
Thermal and optical performance characteristics of a spatial light modulator with high average power picosecond laser exposure applied to materials processing applications
摘要： A spatial light modulator (SLM) addressed with Computer Generated Holograms (CGH’s) can create structured light fields when an incident laser beam is diffracted by a phase CGH. The power handling limitations of SLMs based on a liquid crystal layer have always been of some concern. Now, with careful engineering of chip thermal management, we present the detailed optical phase and temperature response of a liquid cooled SLM exposed to picosecond laser average powers up to 220W at 1064nm – new knowledge critical for determining device performance at high laser powers. SLM chip temperature rose linearly with incident laser exposure, increasing by only 5°C at 220W incident power, measured with a thermal imaging camera. Thermal response time with continuous exposure was 1-2 seconds. The optical phase response with incident power approaches 2π radians with average powers up to 130W while above this power, liquid crystal thickness variations limit phase response to just over π radians. These remarkable performance characteristics show that liquid crystal based SLM technology is highly robust when efficiently cooled. High speed, multi-beam plasmonic surface micro-structuring at a coverage rate of 8cm2s-1 is achieved on polished metal surfaces at 25W exposure, while diffractive multi-beam surface ablation on stainless steel at an ablation rate of ～4mm3min-1 is demonstrated with average power 100W. Continuous exposure for many hours exceeding 100W laser power did not result in any detectable drop in diffraction efficiency hence no permanent changes in SLM phase response characteristics have been observed This research work will help to accelerate the use of liquid crystal SLMs for both scientific and ultra-high throughput laser-materials micro-structuring applications.
关键词： Spatial light modulator,active cooling,high average power picosecond laser,high power laser micro-machining
更新于2025-09-12 10:27:22
-
Investigation of the influence of welding parameters on the weld geometry when welding structural steel with oscillated high-power laser beam
摘要： Oscillation of the laser beam has been applied to achieve a positive influence on the efficiency of the welding process and the quality of the weld seam. In this work a 10 kW laser beam from a fiber laser was oscillated with frequencies up to 1000 Hz for bead on plate welds in 15 mm thick structural steel to investigate the influence of beam oscillation on geometrical dimensions of the weld seam. The laser beam was oscillated transversally with a given amplitude for each frequency. The parameter set to be varied was laser power, welding speed and focal point position according to the highest influence on the formation of the weld seam and the welding process. The results obtained show that lower oscillation frequencies in the range of 200 Hz with higher amplitudes in combination with either low welding speeds or higher laser powers up to 10 kW had the greatest influence on the geometry of the weld seam.
关键词： fibre laser,transversal scanning,structural steel,oscillating laser beam,high power laser
更新于2025-09-12 10:27:22
-
Implementation of a phase plate for the generation of homogeneous focal-spot intensity distributions at the high-energy short-pulse laser facility PHELIX
摘要： We propose and demonstrate the use of random phase plates (RPPs) for high-energy sub-picosecond lasers. Contrarily to previous work related to nanosecond lasers, an RPP poses technical challenges with ultrashort-pulse lasers. Here, we implement the RPP near the beginning of the ampli?er and image-relay it throughout the laser ampli?er. With this, we obtain a uniform intensity distribution in the focus over an area 1600 times the diffraction limit. This method shows no signi?cant drawbacks for the laser and it has been implemented at the PHELIX laser facility where it is now available for users.
关键词： high-power laser,phase plate,short-pulse laser,beam shaping
更新于2025-09-12 10:27:22