In case of fluorescent lamp the mercury vapour pressure is maintained at lower level such that 60 of the total input energy gets converted into 253 7 nm single line.
Low pressure mercury vapour lamp circuit diagram.
As pressure increases the chance of multiple collisions gets increased.
When a mercury vapor lamp is first turned on it will produce a dark blue glow because only a small amount of the mercury is ionized and the gas pressure in the arc tube is very low so much of the light is produced in the ultraviolet mercury bands.
The aperture phosphor coated lamps that jelight company produces employ the same basic design as the double bore low pressure mercury vapor lamps with the exception of a special phosphor coating.
Low pressure and high pressure low pressure sodium lamps are highly efficient electrical light sources but their yellow light restricts applications to outdoor lighting such as street lamps where they are widely used.
A fluorescent lamp is a low weight mercury vapour lamp that uses fluorescence to deliver visible light.
Amalgam lamps use a mercury amalgam mix to control mercury vapor pressure.
Two varieties of such lamps exist.
Again transition of the electrons requires least amount of input energy from a colliding electron.
An electric current in the gas energizes mercury vapor which delivers ultraviolet radiation through discharge process and the ultraviolet radiation causes the phosphor coating of the lamp inner wall to radiate visible light.
Rather than a cold spot the lamp s amalgam spot on pellet regulates mercury vapor pressure during operation and yields up to three times the uvc output of a standard low pressure mercury lamp of the same length.