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.
High pressure mercury vapour lamp construction and working.
A mercury vapor lamp is a gas discharge lamp that uses an electric arc through vaporized mercury to produce light the arc discharge is generally confined to a small fused quartz arc tube mounted within a larger borosilicate glass bulb.
Figure 1 a typical high pressure mercury lamp.
In either case the outer bulb provides thermal insulation protection from the ultraviolet radiation the.
The mercury vapor lamp is a high intensity discharge lamp.
Two varieties of such lamps exist.
Again transition of the electrons requires least amount of input energy from a colliding electron.
This is different from fluorescents which use the mercury vapor arc to create a weaker light that mainly creates uv light to excite the phosphors.
At the heart of the lamp is an arc tube which is fabricated from quartz with a tungsten electrode disposed at either end.
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.
Working of mercury vapor lamp the mercury vapor and neon gas pink in color present in the bulb requires high voltage at the starting to illuminate light.
As pressure increases the chance of.
The mercury vapor lamp is similar in construction to the sodium vapor lamp.
The outer bulb may be clear or coated with a phosphor.
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 low pressure sodium vapor lamp or lpsv lamp is termed as a miscellaneous discharge lamp as it possesses some characteristics of high intensity discharge hid lamps as well as it resembles fluorescent lamps in other areas.
Basically an lpsv lamp is a gas discharge lamp that uses sodium in an excited state to produce light.
When high voltage is applied we can observe that the neon gas which was originally in pink color will change into orange color by heating.
The extensive use of the mercury vapor lamp depends entirely upon the versatility of the mercury vapor as regards pressure temperature voltage and other characteristics each change resulting in a lamp of different spectral quality and efficiency.
