Radiation

The most appropriate way of heating gases and vapors to a high Temperature is a discharge. By selecting a particular gas or vapor can be selective radiation in the interest of the spectrum. Thus, when using gas or vapor as a source of optical radiation can be increased efficiency and get the desired spectrum of radiation. Luminescence. At the heart of the action of fluorescent light sources are different ways of making certain types of energy directly into optical radiation.

It occurs when the localized absorption of external energy particles of matter and subsequent radiation of this energy and therefore not related to the thermal state of the body. Due to this fact, perhaps more luminescence efficient conversion of input energy into optical radiation. Luminescence is called spontaneous emission in excess compared to the heat, if its duration is much greater than the oscillation period electromagnetic wave corresponding to the radiation. Luminescence is observed in gaseous, liquid and solids. The luminescence spectrum may consist of individual lines (emission of individual atoms and ions), the bands (Emission of molecules) and continuous sections (emission of solids and liquids). Solid or liquid substance capable of emitting light under the influence of different kinds of excitations, called phosphors. In contemporary sources light is mainly used electroluminescence and photoluminescence.

Electroluminescence - optical emission of atoms, ions, molecules, liquids and solids under the impact of electrons, ions accelerated in the electric fields up to energies sufficient to excite. Electroluminescence of gases and vapors are excited by electrons in the gas discharge is the primary cause of radiation discharges and is widely used in discharge sources light. Different types of EL phosphors used in electroluminescent panels. Phosphors glow under the impact of electrons of sufficient speed, known as cathodoluminescence, used in cathode ray tubes, picture tubes, electron-optical converters, some special light sources and other devices. Photoluminescence - optical emission resulting from absorption of optical radiation another source. In the vapors and gases there are many types of photoluminescence by the energy of the absorbed photons and the structure of the absorbing atoms, ions or molecules. For example, resonance fluorescence of vapors and gases, and many other species that play an important role in the emission of discharge lamps, especially low pressure. Photoluminescence of phosphors are widely used in fluorescent and other discharge lamps. Currently, the most widely used light sources based on the conversion of electrical energy into optical radiation, ie, by the nature of the primary energy of the category electric. Among them are the most numerous incandescent and discharge lamps of various types.