Steve K
Flashlight Enthusiast
hi gang,
I just learned that a manufacturer of vehicle lights is now using white leds in their taillights and turn signals, and using the red or amber lenses to get the desired color. My initial reaction was predictable... "are they crazy??". The arguement is that white LEDs have gotten cheaper than other colors, and this is now the most cost effective method to make these lights.
Well, I don't know what LEDs they are using, so I don't know their actual costs. As one benchmark, I looked up the price of amber, red, and white Cree XP-E's at Digi-key. They aren't exactly equivalent in a variety of ways, but the rough numbers show that the amber LED costs $2.10 in quantity (p/n XPEAMB-L1-R250-00401TR-ND), the red LED is $1.39 in quantity (p/n XPERED-L1-0000-00401TR-ND), and the white is $1.68 in quantity (p/n XPEWHT-L1-0000-00F08-ND).
Based on this, the red LED looks like a better buy than the white, but I can see an arguement for using white LEDs to make amber light.
The engineer in me still says that it's crazy to use a blue LED die to illuminate phosphors that re-emit a fairly full spectrum of light, and then filter out a lot of that light when you can just buy a LED to produce the desired wavelength directly. It's harder to argue the economics, especially when you can design and build just one electronic circuit board and slap different colored lenses on the front. Crazy, or not??
I just learned that a manufacturer of vehicle lights is now using white leds in their taillights and turn signals, and using the red or amber lenses to get the desired color. My initial reaction was predictable... "are they crazy??". The arguement is that white LEDs have gotten cheaper than other colors, and this is now the most cost effective method to make these lights.
Well, I don't know what LEDs they are using, so I don't know their actual costs. As one benchmark, I looked up the price of amber, red, and white Cree XP-E's at Digi-key. They aren't exactly equivalent in a variety of ways, but the rough numbers show that the amber LED costs $2.10 in quantity (p/n XPEAMB-L1-R250-00401TR-ND), the red LED is $1.39 in quantity (p/n XPERED-L1-0000-00401TR-ND), and the white is $1.68 in quantity (p/n XPEWHT-L1-0000-00F08-ND).
Based on this, the red LED looks like a better buy than the white, but I can see an arguement for using white LEDs to make amber light.
The engineer in me still says that it's crazy to use a blue LED die to illuminate phosphors that re-emit a fairly full spectrum of light, and then filter out a lot of that light when you can just buy a LED to produce the desired wavelength directly. It's harder to argue the economics, especially when you can design and build just one electronic circuit board and slap different colored lenses on the front. Crazy, or not??