How a Philips light bulb uses blue LEDs to produce white light
News from ExtremeTech:

Figure it out yet? Any idea what’s going on in the image above? Here’s a hint: that’s a Philips LED bulb in action.

There’s no two ways around it: many potential buyers have been turned off by the yellow cap pieces on some LED bulbs. These bulbs might be efficient, increasingly affordable, and last for upwards of 25,000 hours, but what the heck is with that day glow yellow?

Those three yellow pieces on the top of certain LED bulbs are the remote phosphor… and they are not there just because some misguided designer thought they looked cool. These are a crucial part of the design for one reason, which the image above makes abundantly clear: the bulb uses blue LEDs. What the remote phosphor does is convert that blue light to a shade that is more acceptable to what we expect from indoor lighting. In this case it’s 2700K, or warm yellow.

So, as you probably guessed by now, the image shows a bulb that is missing one of its remote phosphor panels. The phosphors that are in place are doing exactly what phosphors do — emit light through the process of luminesc…………… continues on ExtremeTech

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Bluetooth Light Bulb Will Simplify Your Life (or Make You Lazy)
News from The Gadgeteer:

by Ian Lim on August 26, 2012 · 1 comment

in Home Tech, News

You’ve got your popcorn and drinks, you’ve got your movie lined up, you plonk into your sofa ….. and you’ve forgotten to turn the lights off. Well the Bluetooth Bulb will save you having to get up off the sofa to remedy this. The bulb uses low-power LED technology and replaces standard bulbs. You download an app to your smartphone and pair the bulb to your device to control the light.  You will be able to turn the bulb on and off, control the brightness, set automatic timers ,and with the RGB model, select multiple colours for ambiance. You don’t have to worr…………… continues on The Gadgeteer

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