The $64,000 question

[NPS Ranger]

Is a dual (or triple) color LED the same intensity as a single color LED used in the same lightbar? For example, if you take a Liberty DUO with R/B modules and set it to flash in red, will the modules be as bright as a single color Liberty in red? Will the DUO in blue be as bright as a regular Liberty in blue?


Today I happened to see a NJSP and PSP vehicle close to each other with the lightbars operating, NJSP with the regular Liberty and PSP with the new DUO. This was mid-morning in bright sunlight. The new DUO looked considerably less bright comparing color for color, red to red, blue to blue. Don't think they would have been running it in reduced intensity mode at 9 AM. Haven't seen a similar comparison with Fedsig 2 or 3 color Spectralux modules compared to single color modules, or any other manufacturers.


Anyone see the new multi-color modules side by side with the single color ones for comparison?

 

[theroofable]

Good question! I guess you would have to count the number of leds per module. If a duo module has the same number as the single, then it would not be as bright as the standard. Unless they use color changing LEDs, then you would actually have to an eye comparison. Oh, why is this a 64k question

 

[Shawn L]

there may be 2 times the amount of led's in a DUO but here is my theory


say for round numbers sake a standard liberty uses 6 red leds in a 500 series sized head, and say the duo uses 6 red and 6 blue , you would have the same number of red diodes per module, but you loose the reflector space on the duo, every place that there is a blue diode, in the standard module there would be more reflective surface.


this could explain some of the perceived loss of brightness,

 

[dcb]

That is strange, the Whelen DUO does not use dual color LEDs... and I don't believe the Spectralux does either.

SpectraLux from Federal Signal is available with multi-color diodes... 4-colors per diode, as used in the Vision SLR.


The Valor (and the Impaxx) use multiple rows of single colored LEDs.

 

[J. Forbes]

SpectraLux from Federal Signal is available with multi-color diodes... 4-colors per diode, as used in the Vision SLR.

The Valor (and the Impaxx) use multiple rows of single colored LEDs.

Actually it is four diodes per chipset just like a SoundOff mighty night light or pinnacle alley light. Axixtech is the patent holder for multi color diodes (don't see them sharing any time soon). The Vision SLR has four diodes per led position; one red, one blue, one amber, & one white. The Valor and liberty (duo & trio) use alternating leds in a single row in each reflector.

 

[bluestinger90]

Axixtech holds a patent for putting RGB diodes in lightheads? Do you have a source for this?

 

[FDNY 10-75]

From what I have seen in person, the dual color Valor (SpectraLux) is brighter than the single color legend.

 

[J. Forbes]

I remember seeing four LEDs per vertical row on the new Vision as you describe, I think that's part of why it is so expensive.

I can guarantee you that Axixtech/Brooking/Juluen does not have a patent on multi-color LED. Several of the Taiwanese manufacturers are using them. I'm not aware any of major LED manufacturer (Lumileds, Osram, Cree) who make nearly all the LEDs for the big warning light companies making them, there just isn't a high enough demand in other industries.


-Jared

Guarantee, bet, or otherwise wager??????


Patent.pdf