The black light is the generic name of a light uttering mainly on the short light (ultraviolet rays) of the wavelength and light (near-ultraviolet radiation) around 400nm than 380nm of the visible domain. Because high light of the energy comes out than visible light, various reactions are seen by a fluorescence reaction and the object which are not provided by the visible light. It varies, and it is wide, and the use is used from the purpose of fluorescence confirmation and the hobby the lure to the forged judgment of the bill and an industrial ultraviolet rays sounding out wound light.

Wave Length

wavelengthA wavelength of the light to approximately 380nm – 750nm becomes the visible light that a human being is visible like this image. In contrast, I call wavelengths less than 380nm ultraviolet rays, and it is usually for invisible light with eyes. Therefore it is very weak and feels the light to go out of the black light with the human eyes, but there is really much “invisible light” and appears.

The risk of Ultraviolet rays

危険性図I call ultraviolet rays of 200-380nm near-ultraviolet radiation in particular and am shared with UVA, UVB, UVC more from there. The ultraviolet rays have an influence by the human body by the wavelength. It is by industrial and few duties of the influence, and the black light to sell in us is relatively good for the human body and adopts a wavelength of used UVA. (365nm – 405nm)

A wavelength of 315-380nm. The ultraviolet rays LED which we handle deals with this domain mainly. It is detrimental when I irradiate skin during long time. In addition, I feel it to be gloomy because there is little visible light, but am dangerous because strong light appears like normal white LED when I look it in the eye.
A wavelength of 280-315nm. So-called sunburns are generated for the wavelength of this domain.
When I expose it and am irradiated, it has a long-time adverse effect than UV-A.
A wavelength of 200-280nm. It is cut by the light from sunlight by the ozone layer and hardly takes it routinely.
Influence is strong, and germicidal lights are used in this wavelength range for the living body in particular in near-ultraviolet radiation

Where is it used?

Because the ultraviolet rays give off almost none of the light of the visible light, there cannot be the thing used as a normal “light”. Because there was little visible light by just that much, was very superior to watch a fluorescence reaction; become light. Therefore I am used in fluorescence sounding out wound inspection with the need to see only a fluorescence reaction, inspection of the fluorescence ink in the paper money, various places including the confirmation of the urinary spray of water of the restroom circumference.