Advantage to LEDs?

juslearnin

Newly Enlightened
Joined
Nov 23, 2003
Messages
28
To me there are several advantages to leds for lighting:long bulb life, durability, possibly color, but by far the greatest is increased run time. It seems like as one moves into the brighter luxeons you start to lose the advantage of run time. Although the brightest luxeons are now approaching the brightness of an incandescent, it seems like their run time is rapidly approaching that of an incandescent as well. Is this a temporary trend or an insurmountable technological hurdle? Or, am I just crazy (a distinct possibility)?
 

raggie33

*the raggedier*
Joined
Aug 11, 2003
Messages
13,451
i was under the impresion that halogen was just as eficant as led. but a course ya cant beat the fact that if ya drop ya halogen bulb flashlight youre nOt going to be able to use the bulb it will blow.but a led will still work
 
B

Birmingham47

Guest
Shock proof lighting is the advantage. Not to mention the bulb won't burn out. The higher watt LEDs use more power. Thus less battery life. But it's already improving. The Princeton Tec Impact XL goes 50 hours on 4 AAs and it's a one watt LED. With time the technology will improve and the price will drop.
 

Harrkev

Enlightened
Joined
Aug 30, 2001
Messages
443
Location
Colorado Springs, CO
Also, as your batteries die, the xenon will yellow. The LED will just become more efficient.

ARC flashlights have a "moon" mode. Ever see a moon mode on a Surefire?

Advantage - LED.
 

Kram

Newly Enlightened
Joined
Jan 21, 2003
Messages
86
Location
Texas
Actually, Juslearnin, I agree. LEDs do have the distinct advantages of durability and reliability (in properly designed lights, that is) and color. But for me, the big advantage is the efficiency of light generation in terms of energy usage. This advantage starts to vanish in the luxeon world, particularly in the high-end overdriven segment. I know for a lot of people on this forum, brighter is better. I've always had the mindset, though, that if I have enough light to accomplish what I want, then brighter is just a waste. I've seen some indications in discussions here that night vision varies substantially between people, which could have some bearing on the differences of opinions you will find expressed here.

Glad you found this forum. You'll enjoy it. I've never seen a brighter /ubbthreads/images/graemlins/wink.gif, more reasonable group of folks than you'll find here.

Mark
 

briteguy

Newly Enlightened
Joined
Nov 26, 2003
Messages
177
Location
Surf City, CA
LEDs are only more efficient when the battery energy start to drop-off. The LEDs continues to glow with the whatever amount of energy left in the batteries. This could mean hundreds of hours even for LS in producing keychain light levl output. For people carrying LS lights, that level is not consider useful light output; therefor the measruement for the LS runtime is usually cut off at 1lumen.

The actual efficiency of LEDs in producing lumen per watt is probaly simmilar to comparable incand bulb of same power rating.
 

roguesw

Enlightened
Joined
Dec 19, 2002
Messages
840
Location
Tokyo, Japan
i think as the buck/boost circuits continue to evolve, we will see efficiency in run times increase while maintaining the same level of lumens. the other development is a multilevel led light like hte U2 and VIP, with variable level of lights to serve all your needs
 
J

js2makefun

Guest
G'day juslearnin, and et al.,

My acquisition ventures to LED illumination were initially encouraged by the resistance to impulse shock. While I don't intentionally abuse my flashlights/torches, they are used quite a bit and dropped occasionally. Just talk with those who have made a significant investment in a working light only to have it out of commission from a drop or other impact. [serious bummer at times! and inconvienient at others...]

The usability aspect was refreshing. I found that LED lights illuminate a general area nicely, similar to the sunlight principle where I was able to navigate without having to pan the light about. [of course there are a few units that are exceptions to this, namely those that have a pretty serious lense to focus the output] For my applications I find the general flood light feature to be far more useful.

Lastly, I really appreciate the ability to utilize the power efficiently from the batteries. [more bang for the buck] Nice to know that I've got more from my battery investment.

Cheers!
 

Kram

Newly Enlightened
Joined
Jan 21, 2003
Messages
86
Location
Texas
Briteguy,

It appears that there is some debate about the efficiency of LEDs vs incandescent lights. As I indicated, for MY purposes, and for many practical applications, the fact that I can get a much longer period of usable light out of the same batteries (when compared to incandescent) is my primary consideration. Actually, this turns out to be a complex discussion due to differences in spectral characteristics and the way the measurments are defined, but here is a link that I think pretty much lays it out:

http://members.misty.com/don/lede.html

In a nutshell, indications are that in terms of lumens/watt, LEDs are somewhat more efficient than incandescents but are only now beginning to approach flourescent lights in efficiency. I think they will continue to improve in efficiency and brightness for a while, yet.

Of course, I also like LEDs for portable lighting because the idea of having a solid state light just appeals to me aesthetically.
/ubbthreads/images/graemlins/grin.gif

Mark
 

briteguy

Newly Enlightened
Joined
Nov 26, 2003
Messages
177
Location
Surf City, CA
There is no doubt that LED take good advantage of useful battery energy. They are becoming more and more efficient as manufacturers resolve thermo issues.

It's very interesting as the LED output reaches upward and HID wattage practially continues to drop. Where the two meet would be the subject of another good thread.

Thanks, Mark. I learn so much from the Forum.

John
 

Doug Owen

Flashlight Enthusiast
Joined
Jan 30, 2003
Messages
1,992
I too see LEDs as 'the way to go' at the low end of things, say under a Watt. In the few Watts category, Halogens start to get the nod, at a dozen or so, fluorescents take over.

Long life (if not abused by overdriving) and long working range of levels (indeed even a slight increase in efficiency for lower levels in most cases) are also strong points making LEDs the best call.

I wouldn't hold my breath for quantum leaps forward in efficiency, however. A two fold increase in either LED or converter efficiency will only double the output, not really all that significant in terms of what your eyes see. And an increase of this size is clearly not possible in a converter already at 50% or higher (as almost all are). This large an improvement in LEDs is likely to take some time, if it's possible at all. Sure things will get better, but making over 40 lumens/watt is a long way to go.

So, I see LEDs as the call under a Watt, everything else is a trade-off.

Doug Owen
 
Top