[harshita]

Gas Discharge lamps
In 1910 new category of light sources are used based on the principal of gas discharge. Gas discharge can be under low pressure or high pressure

1. Low pressure mercury vapour lamp ( Fluorescent Lamp )
   
2. CFL ( compact Fluorescent Lamp )
   
3. HID (High Intensity Discharge ) lamp
   
   1. High pressure mercury vapour lamps (HPMV)
      
   2. Metal halide lamps (MH)
      
   3. High pressure sodium vapour lamps (HPSV)
      
   4. Low pressure sodium vapour lamps (LPSV)
      

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