Laser beam machining

Laser beam machining (LBM) is a form of machining that uses heat directed from a laser beam. This process uses thermal energy to remove material from metallic or nonmetallic surfaces. The high frequency of monochromatic light will fall on the surface, thus heating, melting and vaporizing the material due to the impinge of photons (see Coulomb explosion). Laser beam machining is best suited for brittle materials with low conductivity, but can be used on most materials. Laser beam machining can be done on glass without melting the surface. With photosensitive glass, the laser alters the chemical structure of the glass allowing it to be selectively etched. The glass is also referred to as photomachinable glass. The advantage of photomachinable glass is that it can produce precisely vertical walls and the native glass is suitable for many biological applications such as substrates for genetic analysis. There are many different types of lasers including gas, solid states lasers, and excimer. Some of the most commonly used gases consist of; He-Ne, Ar, and Carbon dioxide laser. Solid-state lasers are designed by doping a rare element into various host materials. Unlike in gas lasers, solid state lasers are pumped optically by flash lamps or arc lamps. Ruby is one of the frequently used host materials in this type of laser. A ruby laser is a type of the solid state laser whose laser medium is a synthetic ruby crystal. The synthetic ruby rod is optically pumped using a xenon flashtube before it is used as an active laser medium. YAG is an abbreviation for yttrium aluminum garnet which are crystals that are used for solid-state lasers while Nd:YAG refers to neodymium-doped yttrium aluminum garnet crystals that are used in the solid-state lasers as the laser mediate. YAG lasers emit a wavelength of light waves with high energy. Nd:glass is neodymium–doped gain media made of either silicate or phosphate materials that are used in fiber laser.