LED Evolution could replace light bulbs


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DigMe
April 15, 2005, 11:14 AM
Article Here (http://news.yahoo.com/news?tmpl=story&u=/ap/20050415/ap_on_hi_te/led_lighting)

There are some interesting tidbits in this article that could translate into evolution of the tactical light world.

Here's the main part that interested me:


Just this week, researchers at the Lighting Research Center at Rensselaer Polytechnic Institute in Troy, N.Y., said they had boosted the light output per watt of a white LED to almost six times that of an incandescent light bulb, beating even a compact fluorescent bulb in efficiency.


The current generation of mass-produced white LEDs is not as effective. It's about twice as good as a light bulb of the same wattage, but the energy savings aren't enough to overcome the major drawback of being expensive.


Are Luxeon LEDs included as "the current generation of mass-produced white LEDs"? If so that means they've developed LEDs that are currently 3 times brighter than that. Cool! It seems like now is the time to wait on buying a premium LED flashlight as they might soon be offering much brighter models.

brad cook

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Jay Kominek
April 15, 2005, 12:51 PM
Are Luxeon LEDs included as "the current generation of mass-produced white LEDs"? I expect so.
It seems like now is the time to wait on buying a premium LED flashlight as they might soon be offering much brighter models. If by "soon" you mean 5 to 10 years, then, yes.

That article is about researchers doing it. Next they'll have to figure out how to make them economical on a large scale. (Not necessarily possible.) And companies will have to ramp up production of them. And they'll still be significantly more expensive for the first few years. Blue LEDs, which have been around for 10 years or so, are still a bit more expensive than red ones. And I think violet (havn't seen many of those, eh?) are still a lot more expensive, and they've been around for a couple of years.

Certainly increase demand for LED lighting could accelerate that. But I wouldn't change my light buying plans if I were you.

Perfesser
April 17, 2005, 09:10 AM
The problem with LED's in flashlights is that they are designed to project light forwards. The rounded end of the LED acts like a lens, and the 'emitter' is usually a small area - white LED's are a different design at the emitter but still a lens at the front. If you look at the business end of an LED flashlight there is a flat reflector or none at all since the LED doesn't emit much usable light to the sides. Remember that LED's were originally designed as indicators, not illuminators.
A standard bulb, OTOH, emits light in a circle (torus) around the glowing filament and this light can be focused forward by a parabolic reflector into a narrow bright beam. I don't see any million CP LED spotlights or LED headlights coming out anytime soon.
I'm surprised at how much light even a small LED handlight puts out in the house but they don't work too well looking for varmints 100 yards or more out in the pasture.
I'm thinking about replacing all the LED's in a small flashlight with infrared LED's to make an illuminator for a night vision scope.

Double Naught Spy
April 17, 2005, 06:20 PM
LEDs can be made to emit light differently. Plus, companies like Inova are using concentric lens focussing rings to capture more of the light and orient it forwards as is done with lighthouse lenses. The Inovas are very bright and have a decent range about like a Streamlight Scorpion, but the light is still pretty enemic at this point.

happy old sailor
April 17, 2005, 09:42 PM
i have all the incandesents i need and am buying LED every time i find one i like. i have a small one that with a single LED and 4 AAs, offers light for 200 hours. i sit it on a table aimed at the white ceiling. creats plenty of walking around lite for days. those million candle recharge lamps will light up a coyote many yards away. can we say that we use tools to fit the job. both have use and i really like the long battery life of LEDs. i dont have lions and bears in my yard, but i do have a venomous snake now and then. LEDs will light him up.

Hutch
May 2, 2005, 05:05 PM
<thread drift>I'm informed by my brother-in-law (the EE) that in the not distant future, automobiles will have LED headlights, so there's obviously big progress being made in that direction. He also informs me that car engines will have valves actuated by electric motor, and that electrical systems in autos are going to 48v. He was right about the electric-motor assist power steering, so I guess we'll see. <end thread drift>

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