Apparently according to Wikipedia the UV-Black Lights emit UV-A... Ultraviolet A, long wave, or black light UVA 400 nm–315 nm 3.10–3.94 eV
Below is a
LINK to the info available on
Wiki :-
http://en.wikipedia.org/wiki/Ultraviolet
Ultraviolet (UV) light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV. It is named because the spectrum consists of electromagnetic waves with frequencies higher than those that humans identify as the color violet.
Although ultraviolet radiation is invisible to the human eye, most people are aware of the effects of UV through sunburn, but the UV spectrum has many other effects, both beneficial and damaging, to human health.
UV light is found in sunlight and is emitted by electric arcs and specialized lights such as black lights. It can cause chemical reactions, and causes many substances to glow or fluoresce. Most ultraviolet is classified as non-ionizing radiation. The higher energies of the ultraviolet spectrum from about 150 nm ('vacuum' ultraviolet) are ionizing, but this type of ultraviolet is not very penetrating and is blocked by air.
"Black light"
Main article: Black light
A black light, Wood's light, or UV light is a lamp that emits long-wave UV radiation and very little visible light. Fluorescent black lights are typically made in the same fashion as normal fluorescent lights except that only one phosphor is used, and the 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 nanometres. The color of such lamps is often referred to in the trade as "blacklight blue" or "BLB", to distinguish them lamps from "bug zapper" blacklight ("BL") lamps that do not have the blue Wood's glass. The phosphor typically used for a near 368 to 371 nanometre 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 nanometres is lead-doped barium silicate (BaSi2O5
b+). "Blacklight Blue" lamps peak at 365 nm.
While "black lights" do produce light in the UV range, their spectrum is confined to the long-wave UVA region. Unlike UVB and UVC, which are responsible for the direct DNA damage that leads to skin cancer, black light is limited to lower-energy, longer waves and does not cause sunburn, although it can damage collagen fibers and destroy vitamins A and D in skin.[citation needed]
A black light may also be formed, very inefficiently, 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 cheaper than the fluorescent source, only 0.1% of the input power is converted to usable radiation, as the incandescent light radiates as a black body with very little emission in the UV. Incandescent bulbs used to generate significant UV, due to their inefficiency, may become dangerously hot. More rarely still, high-power (hundreds of watts) mercury-vapor black lights that use a UV-emitting phosphor and an envelope of Wood's glass are made, are used mainly for theatrical and concert displays. They also become very hot during normal use.
Some UV fluorescent bulbs specifically designed to attract insects use the same near-UV emitting phosphor as normal blacklights, but use plain glass instead of the more expensive Wood's glass. Plain glass blocks less of the visible mercury emission spectrum, making them appear light-blue to the naked eye. These lamps are referred to as "blacklight" or "BL" in most lighting catalogs.
Ultraviolet light can also be generated by some light-emitting diodes and laser diodes.
Ultraviolet fluorescent lamps
Fluorescent lamps without a phosphorescent coating to convert UV to visible light, emit ultraviolet light with two peaks at 253.7 nm and 185 nm due to the peak emission of the mercury within the bulb. Eighty-five to ninety percent of the UV produced by these lamps is at 253.7 nm, while only five to ten percent is at 185 nm. Germicidal lamps use quartz (glass) doped with an additive to block the 185 nm wavelength. With the addition of a suitable phosphorescent coating, they can be modified to produce a UVA, UVB, or visible light spectrum (all fluorescent tubes used for domestic and commercial lighting are mercury (Hg) UV emission bulbs at heart).
Such low-pressure mercury lamps are used extensively for disinfection, and in standard form have an optimum operating temperature of about 30 degrees Celsius. Use of a mercury amalgam allows operating temperature to rise to 100 degrees Celsius, and UVC emission to about double or triple per unit of light-arc length. These low-pressure lamps have a typical efficiency of approximately thirty to thirty-five percent, meaning that for every 100 watts of electricity consumed by the lamp, it will produce approximately 30-35 watts of total UV output.
Ultraviolet LEDs
Light-emitting diodes (LEDs) can be manufactured to emit light in the ultraviolet range, although practical LED arrays are very limited below 365 nm. LED efficiency at 365 nm is about 5-8%, whereas efficiency at 395 nm is closer to 20%, and power outputs at these longer UV wavelengths are also better. Such LED arrays are beginning to be used for UV curing applications, and are already successful in digital print applications and inert UV curing environments. Power densities approaching 3,000 mW/cm2 (30 kW/m2) are now possible, and this,
coupled with recent developments by photoinitiator and resin formulators, makes the expansion of LED-cured UV materials likely.
If anyone has any info on plants/wavelengths/ and UV-A emitting 'Black-Lights' please add it to this thread, many thanks - STELTHY
test away brah~
) Controlled X-ray beam are good for young plants.. so that now leaves Infra-Red and Gamma Ray...