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A test target bursts into flame upon irradiation by a continuous-wave kilowatt-level carbon-dioxide laser. The carbon-dioxide laser (CO 2 laser) was one of the earliest gas lasers to be developed. It was invented by Kumar Patel of Bell Labs in 1964 [1] and is still one of the most useful types of laser.
Laser types with distinct laser lines are shown above the wavelength bar, while below are shown lasers that can emit in a wavelength range. The height of the lines and bars gives an indication of the maximal power/pulse energy commercially available, while the color codifies the type of laser material (see the figure description for details).
Laser cutting for metals has the advantage over plasma cutting of being more precise [11] and using less energy when cutting sheet metal; however, most industrial lasers cannot cut through the greater metal thickness that plasma can. Newer laser machines operating at higher power (6000 watts, as contrasted with early laser cutting machines ...
A 1951 USAF resolution test chart is a microscopic optical resolution test device originally defined by the U.S. Air Force MIL-STD-150A standard of 1951. The design provides numerous small target shapes exhibiting a stepped assortment of precise spatial frequency specimens.
Laser and laser amplifier development: Thermal relaxation in pulse-pumped amplifiers causes temporal and spatial variations in the gain crystal, effectively distorting the beam profile of the amplified light. A beam profiler placed at the output of the amplifier yields a wealth of information about transient thermal effects in the crystal.
where t is the depth of cut, P is the laser beam power, v is the cutting velocity, and d is the laser beam spot diameter. [5] The depth of the cut is also influenced by the workpiece material. The material's reflectivity, density, specific heat, and melting point temperature all contribute to the lasers ability to cut the workpiece.
Laser ablation or photoablation (also called laser blasting [1] [2] [3]) is the process of removing material from a solid (or occasionally liquid) surface by irradiating it with a laser beam. At low laser flux, the material is heated by the absorbed laser energy and evaporates or sublimates .
Used also for aluminium and other non-ferrous metals, especially for thicker welds. In comparison with argon, helium provides more energy-rich but less stable arc. Helium and carbon dioxide were the first shielding gases used, since the beginning of World War 2. Helium is used as a shield gas in laser welding for carbon dioxide lasers. [8]