Nyc subways were still using original mercury arc rectifiers to convert ac to dc power up until the end of the 20th century.
Low pressure mercury lamp uses.
The most common form of germicidal lamp looks similar to an ordinary fluorescent lamp but the tube contains no fluorescent phosphor in addition rather than being made of ordinary borosilicate glass the tube is made of fused quartz or vycor 7913 glass.
The first lamp was a round bulb with two electrodes.
In low pressure mercury vapor lamps only the lines at 184 nm and 254 nm are present.
The lamps can be constructed to emit primarily in the uv a around 400 nm or uv c around.
Hach replacement uv for toc analyzers arc imaging chromatography photochemistry calibration of uv detectors calibrations of spectrophotometer and more.
Lps development and inventors.
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.
Amalgam lamps use a mercury amalgam mix to control mercury vapor pressure.
Right around 1900 the mercury arc rectifier was developed this luminous device was very important for power conversion.
Determine required and desired light levels energy efficiency requirements intensity and clarity of light length of life and costs.
Low pressure mercury lamps are very similar to a fluorescent lamp with a wavelength of 253 7 nm 1182 5 thz.
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.
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.
Since 1978 for a variety of applications such as.
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.
These early low pressure lamps used a lot of mercury today s lamps use a tiny amount of mercury.
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.
In medium pressure mercury vapor lamps the lines from 200 600 nm are present.
Fused silica is used in the manufacturing to keep the 184 nm light from being absorbed.
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 lamps have been manufactured in jelight company inc.
Ushio germicidal lamps are low pressure mercury arc lamps that emit radiation peaking at 253 7nm uv c.
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.
The larger lps lamps used in street lighting for the most part do not use argon.
