Fluorescent Fluorescent<unk>  tubes are typically made in the same fashion as normal fluorescent tubes except that a phosphor that emits UVA light instead of visible white light is used. The type most commonly used for<unk> s, designated<unk> <unk> ue or "BLB" by the industry, has a dark<unk> ue filter coating on the tube, which filters out most visible light, so that fluorescence effects can be observed. These tubes have a dim violet glow when operating. They should not be confused with<unk> " or "BL" tubes, which have no filter coating, and have a brighter<unk> ue color. These are made for use in "bug zapper" insect traps where the emission of visible light does not interfere with the performance of the product. The phosphor typically used for a near 368 to 371 nanometer emission peak is either europium-doped strontium fluoroborate (:) or europium-doped strontium borate (:) while the phosphor used to produce a peak around 350 to 353 nanometres is lead-doped barium silicate (:).<unk> <unk> ue" lamps peak at 365 nm. Compact fluorescent (CF)<unk>  bulb Manufacturers use different numbering systems for<unk>  tubes. Philips uses one system which is becoming outdated (2010), while the (German) Osram system is becoming dominant outside North America. The following table lists the tubes generating<unk> ue, UVA and UVB, in order of decreasing wavelength of the most intense peak. Approximate phosphor compositions, major manufacturer's type numbers and some uses are given as an overview of the types available. "Peak" position is approximated to the nearest 10 nm. "Width" is the measure between points on the shoulders of the peak that represent 50% intensity. +Various phosphor compositions used in<unk>  PhosphorMixture Peak(nm) Width(nm) Philipssuffix Osramsuffix U.S. Type Typical use — 450 50 — /71 — hyperbilirubinaemia, polymerization :Eu 420 30 /03 /72 — photochemical polymerization :Eu 370 20 /08 /73 ("BLB") forensics, lapidary, night clubs :Eu 370 20 — /78 ("BY") insect attraction, polymerization, psoriasis, tanning beds :Pb 350 40 /09 /79 "BL" insect attraction, tanning beds :Pb 350 40 /08 — "BLB" dermatology, lapidary, forensics, night clubs :Ce 340 30 — — — photochemistry :Ce 310 40 — — — medical applications, polymerization FWHM spectral bandwidth of the 370 nm peak is about 20 nm. The tiny secondary peak (2) is light from the mercury vapor line at 404 nm leaking through the filter, which gives the lamp its purple glow. "Bug zapper" tubes Another class of UV fluorescent bulb is designed for use in "bug zapper" flying insect traps. Insects are attracted to the UV light, which they are able to see, and are then electrocuted by the device. These bulbs use the same UV-A emitting phosphor<unk> end as the filtered<unk> , but since they do not need to suppress visible light output, they do not use a purple filter material in the bulb. Plain glass<unk> ocks out less of the visible mercury emission spectrum, making them appear light<unk> ue-violet to the naked eye. These lamps are referred to by the designation<unk> " or "BL" in some North American lighting catalogs. These types are not suitable for applications which require the low visible light output of "BLB" tubes lamps. Incandescent 100-watt incandescent<unk>  bulb A<unk>  may also be formed by simply using a UV filter coating such as Wood's glass on the envelope of a common incandescent bulb. This was the method that was used to create the very first<unk>  sources. Although incandescent<unk>  bulbs are a cheaper alternative to fluorescent tubes, they are exceptionally inefficient at producing UV light since most of the light emitted by the filament is visible light which must be<unk> ocked. Due to its<unk> ack body spectrum, an incandescent light radiates less than 0.1% of its energy as UV light. Incandescent UV bulbs, due to the necessary absorption of the visible light, become very hot during use. This heat is, in fact, encouraged in such bulbs, since a hotter filament increases the proportion of UVA in the<unk> ack-body radiation emitted. This high running-temperature drastically reduces the life of the lamp, however, from a typical 1,000 hours to around 100 hours. Mercury vapor A 160-watt mercury vapor<unk>  High power mercury vapor<unk>  lamps are made in power ratings of 100 to 1,000 watts. These do not use phosphors, but rely on the intensified and slightly broadened 350–375 nm spectral line of mercury from high pressure discharge at between , depending upon the specific type. These lamps use envelopes of Wood's glass or similar optical filter coatings to<unk> ock out all the visible light and also the short wavelength (UVC) lines of mercury at 184.4 and 253.7 nm, which are harmful to the eyes and skin. A few other spectral lines, falling within the pass band of the Wood's glass between 300 and 400 nm, contribute to the output. These lamps are used mainly for theatrical purposes and concert displays. They are more efficient UVA producers per unit of power consumption than fluorescent tubes. LED UV LED Ultraviolet light can be generated by some light-emitting diodes, but wavelengths shorter than 380 nm are uncommon, and the emission peaks are broad, so only the very lowest energy UV photons are emitted, within predominant not visible light.
Blacklight
Wart
Bili light
Beauty Mark
Caul
Gauze
Lint 
MedFlight