What is photoluminescence?
There are two types of photoluminescence and these are fluorescence and phosphorescence. Fluorescent materials absorb light and then emit light instantaneously at a different wavelength. Phosphorescent materials absorb light of short wavelength and then emit light slowly over time also at a different, longer wavelength. It is often the case that the two photoluminescent phenomena can occur at the same time and indeed JALITE produce special high visibility products that are highly conspicuous in both the "daylight" and dark condition to improve visibility of escape paths.These are shown in the picture above this article. Typical safety grade phosphorescent materials absorb in the UV, Blue light visible region (300 - 450nm) of the spectrum and emit in the yellow green (500- 600nm). JALITE materials are covered by the technically correct term phosphorescent. The energy needed to activate it is supplied by common light sources such as daylight, ordinary tungsten filament and the most effective fluorescent lights with a high colour temperature. Under sudden power loss situations, the material immediately appears very bright and is conspicuous at a distance, providing an effective, bright contrast for text and graphical symbols and ensuring that safety messages are quickly recognised. This assists people to orientate themselves so that they can react effectively and evacuate efficiently. JALITE materials are designed specifically to maximize both high initial brightness and persistence which is often expressed as long after glow.. Furthermore, as for the flagship products JALITE AAA and JALITE SB they can be charged easily at low illumination and with short exposure times to light energy.