Health is wealthSodium Vapor Lamp
The light in Sodium Vapor lamp is from an atomic emission process. The mechanism of light emission in a sodium vapor lamp is simple and straight-forward. The filaments of the lamp sputter fast moving electrons, which hit the sodium atoms (vapor) causing the valence electrons of the sodium atoms to excite to higher energy levels and the electrons thus excited relax by emitting the characteristic monochromatic bright yellow light (589nm). It works by electric discharge. Although sodium vapor lamps produce much higher light output (about 90 lumens/watt) they cannot be used in lighting applications where color-rendering property is very crucial. This is because most of the light emitted from a sodium vapor lamp is concentrated in the yellow part of the visible spectrum (around 580-590 nm).
