Showing posts with label uv. Show all posts
Showing posts with label uv. Show all posts

1/26/13

Ultraviolet LED's

So I got a pack of Sparkfun LED's and some UV LED's on the side. A little investigation led to the conclusion that the separate LED's are rather superflous. It turns out the 'violet' LED's in the Sparkfun pack have the exact same wavelength as the LED's sold separately.

They are both of the class called 'UVA' which goes from 400 – 315 nm. The separate LED's do however seem to be a bit brigther. Also the construction itself of the two differ a tiny bit - we are talking sub-millimetre and fractions of degrees.

Here's a table of UV wavelengths, ripped right out of Wikipedia.
UltravioletUV400 – 100 nm3.10 – 12.4 eV
Ultraviolet AUVA400 – 315 nm3.10 – 3.94 eVlong wave, black light
Ultraviolet BUVB315 – 280 nm3.94 – 4.43 eVmedium wave
Ultraviolet CUVC280 – 100 nm4.43 – 12.4 eVshort wave, germicidal
Near UltravioletNUV400 – 300 nm3.10 – 4.13 eVvisible to birds, insects and fish
Middle UltravioletMUV300 – 200 nm4.13 – 6.20 eV
Far UltravioletFUV200 – 122 nm6.20 – 10.16 eV
Hydrogen Lyman-alphaH Lyman-α122 – 121 nm10.16– 10.25 eV
Extreme UltravioletEUV121 – 10 nm10.25 – 124 eV
Vacuum UltravioletVUV200 – 10 nm6.20 – 124 eV