Because mercury lamps are so prevalent in current outdoor lighting and still safe when properly installed in a serviceable fixture the need for these products will.
High pressure mercury lamp construction.
High pressure mercury vapor lamps are commonly used for general lighting purposes.
Ushio germicidal lamps are low pressure mercury arc lamps that emit radiation peaking at 253 7nm uv c.
Designed by experienced engineers and by using quality material in combination with a tightly controlled manufacturing process we provide high quality lamps free of impurities to maintain strong and stable output throughout life of the lamp.
Mercury vapor lamps were the first high intensity discharge lamps to be commercially available for a wide variety of lighting applications.
At the heart of the lamp is an arc tube which is fabricated from quartz with a tungsten electrode disposed at either end.
As pressure increases the chance of multiple collisions gets increased.
1901 the first commercial mercury vapor lamp peter cooper hewitt new york city had a history of innovations in other fields and when he set about on the project of the mercury vapor lamp in 1898 it only took 3 years to develop the first reliable lamp with a acceptable color of light.
Most models produce a bluish white light.
Figure 1 a typical high pressure mercury lamp.
They emit primarily in the blue and green.
Mercury vapor lamps have found the greatest use in industrial applications and outdoor lighting because of their low cost and long life and lamp sizes of up to 1 000 watts.
Mercury vapor lamps are gas discharge lamps that uses an electric arc through vaporized mercury to produce light.
Again transition of the electrons requires least amount of input energy from a colliding electron.
The newer lps lamps contain less mercury than before but this has effected performance negatively.
The lamps can be constructed to emit primarily in the uv a around 400 nm or uv c around 250 nm.
The tube contains a few milligrams of mercury and around 25 50 torr of pure argon as a buffer gas to carry the discharge while the lamp warms up producing.
High pressure sodium lamp hps lamp the hps lamp is the most ubiquitous lamp for street lighting on the planet.
A sodium vapor lamp is a gas discharge lamp that uses sodium in an excited state to produce light at a characteristic wavelength near 589 nm.
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 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.
