The opening meeting of green laser pointer is in the process

Therefore, the first condition is laser-generated: there must be activated to achieve population inversion of the material. Active substance for a period of optical amplifiers, there are a bunch of energy for the E2-E1 = hv of the incident photons into the active substance, then stimulated emission of photons will exceed consumption by stimulated absorption of the photon number, leaving the total stimulated emission dominant position. In this case, the light within the active material further and further strong, so that the output of the laser light energy work material exceeds the energy of incident light, which is the light amplification process. Optical amplification is usually the size of amplification (or gain) coefficient G to describe the physical meaning of light per unit length of active substances through the light intensity after the growth percentage. Propagation of light amplification in the gain medium at the same time, the gain medium and optical cavity, there are a variety of light loss, the introduction of loss coefficient α, the physical meaning of the active substance per unit length of light through the light intensity after the decay of the percentage. Active substances can not be done too long in fact, generally placed at both ends of the active material coated with high reflectivity of two mirrors form a resonant optical cavity, so that the initial light intensity Io will be transmitted back and forth between the reflection lines , equivalent to increasing the length of active medium, and ultimately obtained to determine the size of a light intensity Im. In addition to the ordinary matter into active substances, also require external excitation energy (or pump source). Such a conventional laser should include three parts: work material, the pump source and the optical resonator. The company of  green laser pointer  has got enough orders in the product exhibition of  green laser pointer .
Work material is the material basis of laser-generated, is the core of the laser is used to achieve population inversion and stimulated emission of substances produced by the system. Classification of substances work in two ways: - kind of work is based on the presence of morphological classification of material, work material can be a gas, solid, liquid and semiconductors; the other is generated based on theoretical analysis of laser rate equations applicable at the time the process The energy level structure, can be divided into three-level system (ruby laser material), a four-level systems (CO2, Nd3 +; YAG, He-Ne, etc., omitted). CO2 lasers are CO2, N2 and He gas mixture composed of the working substance, CO2 molecules in the laser transition occurs between two energy levels, promote the development of other components of the two-level CO2 molecules formed between inversion or reduce work material temperature and so on. In the solid-state lasers, mixed with a small amount of transition metal ions or rare-earth ions in crystals or glass as the working substance, the work of particle doping ions, generated by the external energy pump inversion can produce stimulated emission, crystal and glass matrix material. Pump source (excitation source) is to provide energy to achieve the quilt inversion device. According to use excitation energy in the form, pumped way discharge excitation, optical excitation, excitation energy, chemical energy and nuclear energy incentives and other incentives. The opening  meeting of  green laser pointer  is in the process.