Low pressure sodium lamps the most efficient gas discharge lamp type producing up to 200 lumens per watt but at the expense of very poor color.
Low pressure mercury lamp uses.
In medium pressure mercury vapor lamps the lines from 200 600 nm are present.
Lps development and inventors.
Right around 1900 the mercury arc rectifier was developed this luminous device was very important for power conversion.
The larger lps lamps used in street lighting for the most part do not use argon.
Determine required and desired light levels energy efficiency requirements intensity and clarity of light length of life and costs.
Mercury vapor lamps have been used in lighting applications from streets and parking lots to landscape lighting to factories and gymnasiums since the 1940 s.
The lamps can be constructed to emit primarily in the uv a around 400 nm or uv c around.
The first lamp was a round bulb with two electrodes.
These early low pressure lamps used a lot of mercury today s lamps use a tiny amount of mercury.
Low pressure sodium lamps were invented first in 1920 by arthur h.
Neon lighting a widely used form of cold cathode specialty lighting consisting of long tubes filled with various gases at low pressure excited by high voltages used as advertising in neon signs.
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.
Hach replacement uv for toc analyzers arc imaging chromatography photochemistry calibration of uv detectors calibrations of spectrophotometer and more.
In low pressure mercury vapor lamps only the lines at 184 nm and 254 nm are present.
Since 1978 for a variety of applications such as.
Amalgam lamps use a mercury amalgam mix to control mercury vapor pressure.
Ushio germicidal lamps are low pressure mercury arc lamps that emit radiation peaking at 253 7nm uv c.
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.
Fused silica is used in the manufacturing to keep the 184 nm light from being absorbed.
Low pressure mercury lamps have been manufactured in jelight company inc.
Nyc subways were still using original mercury arc rectifiers to convert ac to dc power up until the end of the 20th century.
Argon has a lower glow voltage argon helps the smaller lamps start at a lower voltage.
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.
Low pressure mercury lamps are very similar to a fluorescent lamp with a wavelength of 253 7 nm 1182 5 thz.