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LED Book-Light Suggestions?
Dormous asks: "My wife and I are both night owls and avid readers, and usually one of us goes to bed before the other, hence the need for a small portable light source. We recently had a booklight, and somehow, my wife managed to shatter the light bulb all over the bed. Therefore, I want to find a booklight that uses an LED as the Light Source. Anybody got any ideas where I can find such a thing. I've already tried ThinkGeek."
Umm...try this...
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"we live in a post-ideological world..." - Billy Bragg.
kensington flylight + 5v wall wart + radioshack toggle switch + 10 min of soldering + epoxying the whole mess to the old booklight's clip
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good early evening project, at the cost of about $20 (you can find flylights @ the apple store and compUSA), and cannibalizing the awnsering machine's wall wart.
moox. for a new generation.
Demotech ("Design for self-reliance") is currently working on the Nightreader.
It's a small piece of reflecting foil, put together with two leds sticked in wood and a couple of batteries. The Nightreader is designed to be able to use two or three batteries of various sizes (whatever you have at hand) which have to little power to be used for something else.
Petzl sells a small light weight led headlamp called the tikka. This might solve your problem.
Try the store at Sky and Telescope. They sell LED flashlights with red leds. They are really restfull on the eyes when reading in bed and will not keep your partner awake. They are also small enough to prop-up somewhere to illuminate your book.
Help children born unable to swallow - www.tofs.org.uk
Now try Google
I have two of these, bought through ThinkGeek, and they're great. Both of mine are still on the first set of batteries.
You can convert any flashlight to LED. These guys have a nifty little LED flashlight replacement bulb in all the normal colors. You can buy one here
Mini maglights use a tiny bulb with straight parallel leads stuck in a pair of holes... just about the configuration of a standard LED. Buy a minimaglight, a 2.9something volt LED, and a pair of NiMH AA cells. I suggest the NiMH more for the lower voltage than for rechargeability. That lets you skip trying to fit in a resistor, which I've never managed. LEDs leads tend to be a hair skinnier than the ones on the lamps, so you will probably have to knurl them. I just lightly "bite" them, with vise-grips.
Pull the lamp out just enough to expose a bit of lead without disconnecting it, and use your VOM to see the polarity. Remove the bulb and gouge a little pit at the positive side.
Cut the LED leads to match the bulb.
Test fit. If it doesn't come on, knurl the leads and try again.
You'll probably have to ream out the reflector a little, as the LED is probably slightly bigger around than the bulb.
Mine's lasted for 3 years now, and goes about 20 hours on a charge.
I've seen little LED hiking lights recently, at Eastern Mountain Sports, for not much more than what I've got in the homebrew, though. They're smaller and brighter than mine, and they come with an elastic headband, which is awfully convenient. Most of them, though, use non-standard batteries, so the cost may get out of hand. I just don't know about that part.
I just figured I'd provide something a little kinder, though really less helpful, than what everybody else is probably suggesting.
You can buy LEDs that screw into a standard bulb fitting.
This webside is crammed with all kinds of useful information regarding LEDs and LED torches. Check it out.
I wouldn't use NiMH for this application due to the batteries characteristics. NiMH lose somewhere around 5% of their charge every day just sitting there. High capacity NiCads work just fine and the voltage is lower yet. They are also cheaper. Using them in an application like this you shouldn't have a "memory effect" problem either. NiMH, like Li-ion, are great for high-drain devices.
But I like your idea. That's the way to go!
A headlamp should be not too bright, and provide uniform lighting across the page. This eliminates single LED lights.
The Black Diamond Ion weighs less than 1 oz, and has an easily adjusted wide elastic headband. In less than a minute, you forget you're wearing it. It has 2 LEDs, which provides a more uniform illumination than 1, but still projects bright spots on the page. (all LED lights do this, in my experience. I don't know why, or how much improvement can be expected in the near future). The battery is odd - a 6V that is a little bigger than the eraser on a pencil. It drives the light for far more than the rated 15-20 hours. My son lost his in the backyard the afternoon we went on a trip, and it was still going strong after we returned in the dark the next night. And he continues to use it reading in bed 30 min per night, several weeks later!! I don't know if rechargeables are available in the required size.
The Ion costs less than $20. It is either on or off, not dimmable. It has no auto-shutoff timer. But it is widely available, practically waterproof, and withstands being dropped without a problem.
See: http://www.backpackgeartest.org/reviews/Lighting
Since you want us to use Google for you, how about the top sponsored link: http://www.lightwedge.com/
It's a flat LED illuminated sheet you lay on the page you are reading so the light doesn't shine on your partner.
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"You are not remembered for doing what is expected of you." - Atul Chitnis
Yes, exactly!