Does a fluorescent bulb contain plasma?
The conventional tubular fluorescent lamp contains a plasma gas at a pressure of about 0.4% of atmospheric pressure. The plasma in a fluorescent lamp produces ultraviolet light that is converted to visible light by the phosphor coating on the wall.
Which gas is filled in fluorescent tube?
Construction. A typical mercury fluorescent tube consists of a glass tube, and up to 2400 mm long, filled with argon or krypton gas and containing a drop of liquid mercury.
What chemicals are in fluorescent tubes?
A fluorescent lamp tube is filled with a mix of argon, xenon, neon, or krypton, and mercury vapor. The pressure inside the lamp is around 0.3% of atmospheric pressure.
Do fluorescent tubes contain mercury?
CFLs contain very small amounts of mercury Mercury, an essential part of CFLs, allows a bulb to be an efficient light source. On average, CFLs contain about four milligrams of mercury sealed within the glass tubing.
Why is mercury in fluorescent light bulbs?
Mercury is an essential element in the operation of fluorescent lighting; it allows the bulbs to be an efficient light source. Because CFLs contain trace amounts of mercury, it is important to educate yourself on proper use, recycling and disposal of these products.
Are fluorescent lights AC or DC?
Fluorescent tubes are almost always powered with AC, but this circuit uses DC. Basically, this circuit is a voltage doubler composed by two 1N4007 diodes and two high voltage electrolytic capacitors of 10 μF 350 V. Such capacitors can be easily salvaged from compact fluorescent lamps.
What are the two substances in fluorescent lights?
A fluorescent lamp consists of a glass tube filled with a mixture of argon and mercury vapour. Metal electrodes at each end are coated with an alkaline earth oxide that gives off electrons easily. When current flows through the gas between the electrodes, the gas is ionized and emits ultraviolet radiation.
Do all fluorescent bulbs contain mercury?
On average, CFLs contain about four milligrams of mercury sealed within the glass tubing. By comparison, older thermometers contain about 500 milligrams of mercury – an amount equal to the mercury in over 100 CFLs.
Are fluorescent tubes toxic?
Even though the amount of mercury is relatively small, fluorescent lights must be disposed of as hazardous waste. Mercury is a toxic heavy metal that can cause severe damage to the brain, nervous system, kidneys, lungs, and other vital organs. Pregnant women, infants, and young children are especially at risk.
What element is found inside the fluorescent lamp?
A fluorescent lamp consists of a glass tube filled with a mixture of argon and mercury vapour. Metal electrodes at each end are coated with an alkaline earth oxide that gives off electrons easily.
Why are fluorescent bulbs composed of several elements?
In order to convert the UV light given off by the mercury into visible light, the insides of fluorescent light bulbs are coated in a thin layer of phosphor – specifically, a blend of mixed phosphates. The phosphor layer blocks most of the ultraviolet light and what remains is emitted as visible light.
What type of light is produced by a fluorescent tube?
Fluorescent lamp. A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapor, which produces short-wave ultraviolet light that then causes a phosphor coating on the inside of the lamp to glow.
What is the composition of a typical white fluorescent lamp?
A typical “cool white” fluorescent lamp utilizing two rare-earth-doped phosphors, Tb 3+, Ce 3+: La PO 4 for green and blue emission and Eu: Y 2 O 3 for red. For an explanation of the origin of the individual peaks click on the image. Several of the spectral peaks are directly generated from the mercury arc.
What is a fluorescent lamp?
A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light.
How many lumens is a fluorescent light?
A fluorescent lamp converts electrical energy into useful light much more efficiently than incandescent lamps. The typical luminous efficacy of fluorescent lighting systems is 50–100 lumens per watt, several times the efficacy of incandescent bulbs with comparable light output.