Incandescent Lamp
The incandescent lamp produce light because of the passage of current through its filaments, which is heated to incandescent. Tungsten wire is used, because of its relatevively high meltingpoint. Tungsten halogen have bromide or iodide added to the gas filling.
Discharge lamps
It is depend gas inside and where we can be used :
1. Low Pressure Sodium
These lamps sodium metal is vaporized to a low pressure incide , and will be
produces monochromatic yellow light. These can be used in public lighting.
2. High Pressure Sodium
These lamps operate with sodium vapour at high pressure, and will produce a golden light.
These can be used for public lighting, flood lighting and industrial lighting.
3. High Pressure Mercury
These lamps operate with mercury vapour arc at high pressure, and will produce a cool white
light. These can be used for factory and public lighting.
4. Metal Halide
These lamps are similar with High Pressure Mercury lamps, but contain metallic halide e.g.
indium and sodium also thalium, and can be used for industrial and public lighting
Flourescent Lamp
The flourescent lamps are tube-shaped low pressure discaharge lamp. The light produced by the phosphors activited by the discharge. The phosphors are coated on the inside of the envelope. A choice of colour appearance cool or warm.
These lamps sodium metal is vaporized to a low pressure incide , and will be
produces monochromatic yellow light. These can be used in public lighting.
2. High Pressure Sodium
These lamps operate with sodium vapour at high pressure, and will produce a golden light.
These can be used for public lighting, flood lighting and industrial lighting.
3. High Pressure Mercury
These lamps operate with mercury vapour arc at high pressure, and will produce a cool white
light. These can be used for factory and public lighting.
4. Metal Halide
These lamps are similar with High Pressure Mercury lamps, but contain metallic halide e.g.
indium and sodium also thalium, and can be used for industrial and public lighting
Flourescent Lamp
The flourescent lamps are tube-shaped low pressure discaharge lamp. The light produced by the phosphors activited by the discharge. The phosphors are coated on the inside of the envelope. A choice of colour appearance cool or warm.
