The proportion of this visible light energy is so small that it is shown as "0" in the spectral charts, but in some applications such as UV photography, the visible light is indeed detectable and may be a nuisance. This is caused by visible light "leakage" where minuscule but visible amounts of visible wavelength energy (i.e.
When illuminating a 365 nm LED, however, you will likely notice a dull, bluish-white color emitted. This will maximize the amount of UV-A energy compared to visible light energy and is preferred for most UV-A applications. But, as the chart shows, it is important to notice that a significant portion of the light energy is being emitted in the visible, violet region.Ĭonversely, looking at the 365 nm spectral output, you will notice that virtually all of the light energy is within the invisible UV-A range only, with emission energy tailing off before reaching 400 nm. Of course, the 395 nm LED also emits at wavelengths below 395 nm as well, and the light energy at these wavelengths are very effective at creating fluorescence effects or initiating UV-A reactions. These wavelengths are solidly in the visible, violet portion of the spectrum. The 395 nm LED emits strongest at 395 nm (as defined by the term peak wavelength), but it also emits quite a bit of energy at 400 nm, and even 410 nm. In other words, 395 nm LEDs don't emit at only 395 nm. What you will notice is that both 365 nm and 395 nm LEDs emit over a range of wavelengths both above and below their respective wavelengths. Why is there a difference in the amount of visible light? The chart above shows the spectral output diagram of both the 365 nm (narrow dotted line) and 395 nm (wide dotted line) LEDs. Both types emit in the UV-A wavelength range and are generally capable of producing "blacklight" or curing effects. The 395 nm LED emits a pronounced violet-colored light, while the 365 nm LED emits a dull, bluish-white light (the result of residual light energy that "tails" off into the visible spectrum). What then, will a difference of 30 nm mean? The main difference is that the 395 nm LED emits much more visible light than the 365 nm LED. UV-A wavelengths are safer when compared to stronger UV-B and UV-C rays. Generally speaking, UV-A lights are useful for creating and observing fluorescence effects, as well as for plastics and paint curing. 365 nm and 395 nm for UV-A Applicationsīoth 365 nm and 395 nm options are within the UV-A wavelength range. Or, in other words, 365 nm is "deeper" into the UV spectrum than 395 nm is. For example, 365 nm wavelength UV belongs to a type of ultraviolet known as "UV-A," while 290 nm wavelength UV is considered "UV-B." The wavelength is what determines the type of UV, and this is an important distinction among UV category in terms of application and even safety precautions that are necessary.Īt a basic level, then, you should note that 395 nm is about 30 nm closer to visible light (violet) than 365 nm is. Even though lights at wavelengths below 400 nm are not visible to the human eye, the wavelength value is still nonetheless very important.
0 kommentar(er)
