Ki sa ki se limyè iltravyolèt?
Limyè se yon pati nan yon spectre ki rele Spectrum Elektwomayetik, ki gen ladan tou reyon Gamma, reyon X-, radyasyon iltravyolèt ak enfra-wouj, mikwo ond ak ond radyo.
The Electromagnetic Spectrum is the way scientists refer to a stream of energy (photons). Photons move in waves. The gap between these waves is governed by how much energy the photon has. Big gaps (long waves) indicate lower energy and small gaps (short waves) indicate higher energy. To make it easier to understand, this stream of energy is split into groups according to the gap between the waves - the "wavelength".
Radio waves (long wavelength, low energy) can have as much as a kilometre between each wave whereas at the other end of the spectrum, with visible and ultraviolet light (short wavelength, high energy) the gap is so small it's measured in nm (nanometers – 1 thousand of a millionth of a metre!).
The human eye can see radiation with wavelengths from 400 to 700 nanometers (nm), and so we refer to this as "visible light". Ultraviolet light has a shorter wavelength than visible light, and cannot be seen by humans although for many animals, including reptiles, vision extends well into the ultraviolet.
Sou dyagram ki anba a ou ka wè ki jan limyè iltravyolèt antre nan spectre elektwomayetik la.
Tradisyonèlman, limyè iltravyolèt divize an twa kategori, UVA, UVB ak UVC.
UVA (320-400nm) is an important component of sunlight, and is supplied in small amounts by "ordinary" household bulbs (incandescent lights) and by lighting often described as "full spectrum" light. Larger amounts are supplied by all specialist ultraviolet lamps.
UVA is part of the visible spectrum for reptiles; they see colours and patterns differently to us because of this extra dimension to their vision. Some reptiles rely upon UVA light to identify individuals of their own species by their UVA-reflective markings; many plants and insects also have distinctive UVA reflectance and "patterns" which enable reptiles to recognise them.
Reptil ki ekspoze a limyè UVA yo montre yon konpòtman sosyal ak nivo aktivite ogmante, yo gen plis tandans pou yo dore ak manje epi yo gen plis chans pou yo repwodui paske limyè UVA gen yon efè pozitif sou glann pineal la, yon estrikti ki sansib nan limyè - jis anba a. sèvo a ki reponn a ogmantasyon ak diminisyon nan lajounen ak sezon yo chanje.
UVB (280-320nm) is found in natural sunlight. The atmosphere blocks wavelengths below 290nm so on the earth's surface, the UVB range is from 290 - 320nm. UVB is blocked almost completely by ordinary glass and by most plastics, so it does not pass through windows or the sides of glass vivaria.
It is not provided by normal household lighting or most so-called "full spectrum" lights, but nowadays there is an ever improving and expanding range of lights that can supply UVB in the vivarium.
Gen prèv k ap grandi ke reptil yo ka aktyèlman detekte UVB, byenke si wi ou non li se aktyèlman vizib pou yo pa sèten.
Anpil espès reptil, an patikilye zandolit dijounen ki dore nan limyè solèy la, itilize radyasyon UVB, nan rejyon 290 a 315 nm, pou fasilite foto-biosentèz pre-vitamin D3 (kolekalsiferol) nan po a. Si reptil sa yo prive de longèdonn patikilye radyasyon iltravyolèt sa a, yo gen risk pou yo devlope defisi vitamin D, ki ka manifeste kòm yon maladi metabolik nan zo yo, yon maladi enfim e souvan fatal yo wè twò souvan nan pi gwo zandolit tankou igwan ak bab. dragon.
UVB ka gen lòt efè benefik. Yo te montre li ankouraje pwodiksyon beta-andorfin nan po moun, sa ki lakòz yon sans de byennèt-.Pa gen okenn rezon ki fè yo panse pwosesis sa a rive sèlman nan imen.
UVC (180-280nm) is harmful to living cells; it is naturally filtered from sunlight by the ozone layer, and is never required, nor should be permitted, in artificial lighting.