Spectrum of a fluorescent black light source. FWHM spectral bandwidth of the 370nm peak is about 20nm.

Black light (also Wood's light) is the common name for a lamp emitting electromagnetic radiation that is almost exclusively in the soft near ultraviolet range, and very little visible light. In the United Kingdom this type of lighting is more commonly referred to as simply "UV light". Image File history File links Download high resolution version (1284x827, 18 KB) Summary Spectrum of light from a fluorescent black light with peaks labelled. ... Image File history File links Download high resolution version (1284x827, 18 KB) Summary Spectrum of light from a fluorescent black light with peaks labelled. ... In telecommunication, a full width at half maximum (FWHM) is an expression of the extent of a function, given by the difference between the two extreme values of the independent variable at which the dependent variable is equal to half of its maximum value. ... Lamp can be: A portable light fixture such as a table lamp or reading lamp (common usage) Lamp (electrical component), a replacable component that produces light, such as: Incandescent light bulb, also known as an incandescent lamp Fluorescent lamp Gas discharge lamp Arc lamp Signal lamp, a device used for... Electromagnetic radiation can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields. ... The solar corona as seen in deep ultraviolet light at 17. ... The visible spectrum is the portion of the optical spectrum (light or electromagnetic spectrum) that is visible to the human eye. ...

Description

Fluorescent black lights are typically made in the same fashion as normal fluorescent lights except that only one phosphor is used and the normally clear glass envelope of the bulb may be replaced by a deep-bluish-purple glass called Wood's glass, a nickel-oxide–doped glass, which blocks almost all visible light above 400 nanometers. The color of such lamps is often referred to in the trade as blacklite blue. Assorted types of fluorescent lamps. ... A phosphor is a substance that can exhibit the phenomenon of fluorescence (glowing during absorption of radiation of another kind) or phosphorescence (sustained glowing without further stimulus). ... A black light bulb. ... General Name, Symbol, Number nickel, Ni, 28 Chemical series transition metals Group, Period, Block 10, 4, d Appearance lustrous, metallic and silvery with a gold tinge Atomic mass 58. ... An oxide is a chemical compound of oxygen with other chemical elements. ... In semiconductor production, doping refers to the process of intentionally introducing impurities into an intrinsic semiconductor in order to change its electrical properties. ...

The phosphor typically used for a near 368 to 371 nanometer emission peak is either europium-doped strontium fluoroborate (SrB₄O₇F:Eu²⁺) or europium-doped strontium borate (SrB₄O₇:Eu²⁺) while the phosphor used to produce a peak around 350 to 353 nanometers is lead-doped barium silicate (BaSi₂O₅:Pb⁺). Blacklite blue lamps peak at 365 nm. General Name, Symbol, Number europium, Eu, 63 Chemical series lanthanides Group, Period, Block n/a, 6, f Appearance silvery white Atomic mass 151. ... General Name, Symbol, Number strontium, Sr, 38 Chemical series alkaline earth metals Group, Period, Block 2, 5, s Appearance silvery white metallic Atomic mass 87. ... Borates in chemistry are chemical compounds containing boron bonded to three oxygen atoms written as B(OR)3. ... For PB or pb as an abbreviation, see PB. General Name, Symbol, Number lead, Pb, 82 Chemical series poor metals Group, Period, Block 14, 6, p Appearance bluish gray Atomic mass 207. ... General Name, Symbol, Number barium, Ba, 56 Chemical series alkaline earth metals Group, Period, Block 2, 6, s Appearance silvery white Atomic mass 137. ... In chemistry, a silicate is a compound containing an anion in which one or more central silicon atoms are surrounded by electronegative ligands. ...

A black light may also be formed by simply using Wood's glass instead of clear glass as the envelope for a common incandescent bulb. This was the method used to create the very first black light sources. Though it remains a cheaper alternative to the fluorescent method, it is exceptionally inefficient at producing UV light (a mere few lumens per watt) owing to the black body nature of the incandescent light source. Incandescent UV bulbs, due to their inefficiency, may also become dangerously hot during use. More rarely still, high power (hundreds of watts) mercury vapor black lights can be found which use a UV emitting phosphor and an envelope of woods glass. These lamps are used mainly for theatrical and concert displays and also become very hot during normal use. A black light bulb. ... The incandescent light bulb uses a glowing wire filament heated to white-hot by electrical resistance, to generate light (a process known as thermal radiation). ... As the temperature decreases, the peak of the black body radiation curve moves to lower intensities and longer wavelengths. ... A Mercury Vapor Lamp is a gas discharge lamp which uses mercury in an excited state to produce light. ...

Some UV fluorescent bulbs specifically designed to attract insects for use in bug zappers use the same near UV emitting phosphor as normal blacklights but instead of using the more expensive Wood's glass to filter out most of the visible mercury emission spectrum they instead use plain glass which has the effect of making them appear light blue to the naked eye. Sometimes these bulbs are referred to as "blacklite" or "blacklight blue". A bug zapper is a device that uses a light source to attract insects to an electrical grid, where they are incinerated by the current. ...

Ultraviolet light can be also generated by some light-emitting diodes. Led is also the past tense of the verb to lead Blue, green and red LEDs. ...

Uses

A black light bulb. To the human eye, the light looks much more violet.

"Midnight bowling" utilizing blacklights and the fluorescence of pins to enhance ambience.

The ultraviolet radiation itself is invisible to the human eye, but illuminating certain materials with UV radiation prompts the visible effects of fluorescence and phosphorescence. Black light testing is commonly used to authenticate antiques and banknotes. It is extensively used in non-destructive testing; fluorescing fluids are applied to metal structures and illuminated with a black light. Cracks and other artifacts can easily be detected. Image File history File linksMetadata Download high resolution version (1024x768, 178 KB)A Sanax 15W black light bulb. ... Image File history File linksMetadata Download high resolution version (1024x768, 178 KB)A Sanax 15W black light bulb. ... Image File history File links Download high resolution version (1021x717, 108 KB) Summary Midnight bowling with ultraviolet lights. ... Image File history File links Download high resolution version (1021x717, 108 KB) Summary Midnight bowling with ultraviolet lights. ... Bowling ball and two pins Ten-pin bowling lane Automatic Scorer This article is about the group of games. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized Cadmium selenide (CdSe) quantum dots. ... Phosphorescent powder under visible light, ultraviolet light, and total darkness. ... Antique can stand for any of several things: An antique is an object, often furniture or any other domestic item, that is highly valued because of its age, or because it belongs to a specific time period. ... A £20 Bank of England banknote. ... Hot metal work from a blacksmith In chemistry, a metal (Greek: Metallon) is an element that readily forms positive ions (cations) and has metallic bonds. ...

It is also used to illuminate pictures painted with fluorescent colors (preferably on black velvet to intensify the illusion of self-illumination). The fluorescence it prompts from certain textile fibers, especially those bearing optical brightener residue, is also used as a recreational effect (as seen for instance in the opening credits of the James Bond film A View to a Kill). Velvet is a type of tufted fabric in which the cut threads are very evenly distributed, with a short dense pile, giving it its distinct feel. ... Optical brighteners, optical brightening agents, fluorescent brightening agents or fluorescent whitening agents are dyes that absorb light in the ultraviolet and violet region of the electromagnetic spectrum, and re-emit light in the blue region. ... This article or section does not cite its references or sources. ... For the Ian Fleming short story that inspired the film, see From a View to a Kill. ...

In forensic investigations, black lights are used to reveal the presence of trace evidence, such as blood, urine, semen and saliva, by causing visible fluorescence in these substances. The use of this technique by exposé style television news magazines for reporting on the various unsanitary and mysterious stains found in hotel rooms has become such an oft-repeated stunt that it has been lampooned on comedy shows such as Family Guy and The Office (US). Forensic science (often shortened to forensics) is the application of a broad spectrum of sciences to answer questions of interest to the legal system. ... Trace evidence is evidence that is found at a crime scene in small but measurable amounts. ... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... This article or section is in need of attention from an expert on the subject. ... Horse semen being collected for breeding purposes. ... Saliva is the watery and usually somewhat frothy substance produced in the mouths of humans and some animals. ... An exposé is an article or book intended to reveal shocking or surprising information. ... A newsmagazine, sometimes called news magazine, is a usually weekly magazine featuring articles on current events. ... Family Guy is an American animated television series about a nuclear family in the suburb of Quahog (IPA or ), Rhode Island. ... The Office is an Emmy Award-winning American television comedy that debuted on NBC as a midseason replacement on March 24, 2005. ...

One of the innovations for night and all-weather flying used by the US, UK and Germany during 1939-1945 was the use of UV floodlights to illuminate the instrument panel, giving a variable intensity alternative to the Radium painted instrument faces and pointers, without visible illumination that would give away an aircraft's position. This went so far as to include the printing of charts that were marked in UV-fluorescent inks, and the provision of UV-visible pencils and slide rules such as the E6B. However, the common failure of the light's power inverter on take-offs in bombers, and the night-blindness and crashes caused when the blacklight filter fell off on trainer aircraft led to the system being mostly abandoned. A couple of very simple pencils A pencil is a handheld instrument used to write and draw, usually on paper. ... The slide rule is a portable, mechanical, analog computer usually consisting of three interlocking calibrated strips and a sliding cursor used to record intermediate results. ... The front of a metal E6B. An E6B flight computer commonly used by student pilots. ...

See also

• Wood's lamp
• List of light sources

A Woods lamp is a diagnostic tool used in dermatology by which ultraviolet light is shone (at a wavelength of approximately 365 nanometers) onto the skin of the patient; a technician then observes any subsequent fluorescence. ... A Standard Household Light bulb This page is a list of sources of light. ...

External links

• Electricalfun.com - "Blacklight Fun"

Lighting and Lamps v • d • e
Incandescent:	Conventional - Halogen - Parabolic aluminized reflector (PAR)
Fluorescent:	Compact fluorescent (CFL) - Linear fluorescent - Induction lamp
Gas discharge:	High-intensity discharge (HID) - Mercury-vapor - Metal-halide - Neon - Sodium vapor
Electric arc:	Arc lamp - HMI - Xenon arc - Yablochkov candle
Combustion:	Acetylene/Carbide - Candle - Gas lighting - Kerosene lamp - Limelight - Oil lamp - Safety lamp - Petromax
Other types:	Sulfur lamp - Light-emitting diode (LED) - Fiber optics - Plasma - El wire