Thread: LED Terms 101 and colors

Before NYPD started putting blue in the back, they were buying LED Vision bars with amber LEDs behind red lenses in the back of pods 1 and 7 and it seems minimally affected.



(wait for 0:55... also interestingly enough, they used all 4 tones on the smart siren)

Can anybody comment on the output difference between a red Vertex and white Vertex behind a red taillight lens. I tried a white and it was almost invisible. Would the red Vertex be 25%, 50%, 100%, etc. brighter behind the same lens.

Originally Posted by John Hearne

Can anybody comment on the output difference between a red Vertex and white Vertex behind a red taillight lens. I tried a white and it was almost invisible. Would the red Vertex be 25%, 50%, 100%, etc. brighter behind the same lens.

Always use colored LEDs behind a colored lens, and always the same color (amber LEDs with an amber lens, red/red etc) because if you use, for example, blue LEDs behind a red lens, it'll really be invisible. White LEDs are pretty much universally less effective behind a colored lens, but you can use any color LED behind a clear lens.

A little science. White leds are not really white. They are actually ultraviolet leds making a florescent coating glow whitish. The rub comes from the fact that the ultraviolet light attacks the epoxy dome of the led, shortening its life. Led color is determined by the chemical doping used in producing the diode. Full spectra leds are actually three or four leds in one package. For aircraft use, the led must produce the color of the fixture regardless of the lens color as per the FAA.

id like and try to make my own led lights but i dont know where to get gen 3 leds anyone know where i could get all the parts and what exactly i would need??

Originally Posted by acousticman

A little science. White leds are not really white. They are actually ultraviolet leds making a florescent coating glow whitish. The rub comes from the fact that the ultraviolet light attacks the epoxy dome of the led, shortening its life. Led color is determined by the chemical doping used in producing the diode. Full spectra leds are actually three or four leds in one package. For aircraft use, the led must produce the color of the fixture regardless of the lens color as per the FAA.

I believe you are confusing fluorescent lights with white LEDs. Fluorescent lights use mercury which produces a UV output which is converted by phosphors (phosphorus containing compounds) coating the inside of the bulb to narrow discrete spectrum white light. White LEDs are Blue LEDs that use a similar phosphor.

-Jared