1 Watt White Ultra-Ultra Bright LEDs

[Warske]

I saw these at allelectronics.com and thought some folks might be interested in these for landing lights or signaling.

US $11.50 each mounted on a heat sink. Apparently can be pushed to 3 watts.

A reviewer says "...these are about 50 times as bright as an average 'ultra', 'super' or any other 5mm LED."

These are at http://www.allelectronics.com
white (CAT# LED-110), red (CAT# LED-109), green (CAT# LED-111), blue (CAT# LED-112) and amber (CAT# LED-113).
with a link to a Spec sheet

OEM is http://www.cree.com

I haven't bought one of these, but I've bought many times from All Electronics and found them reliable.

Warske

[Acetronics]

Hi, Warske
3 Watts nominal also exists ... see www.luxeon.com

Alain

[Norman Adlam]

Hi, Warske
3 Watts nominal also exists ... see www.luxeon.com

Alain

Yup,

The Luxeon are pretty good - however the high power also means a high current consumption!

Cheers,

[Acetronics]

:D
you're right ...may be it's a bit too much for a peanut or an indoor ...

Alain

[Warske]

Hi Alain & Norman,

Thanks for the pointer to luxeon.com.

Have you used any particular LEDs from them that you would recommend?

Do you go to them direct or through a distributor?

Thanks

Warske

[sesat]

Warske, I've had good experience with a Luxeon V Portable with a constant current source. I used a Maxim chip to supply power. I'd love a good lens for it (2deg collimater).

These are expensive, the Luxeon III's are available for much less through group purchases on web forums from time to time.

Ram

[Acetronics]

:) I get mine ( and optics ...)

at www.roithner-laser.com ... in Austria

:p I also get 25 000 mcd 5 mm White leds from my retailer ( ~ 1USD / 10 )

Alain

[GeneSS]

One big difference between these new Cree chips and the Luxeons is that the Cree's have 3 times the lumenous flux as the equivilently powered Luxeons. These one watt Cree's have the same flux as the Luxeon III's (3 watt). That's a big improvement. I have been using the Luxeon Stars for over three years and they are great. I have some of the new Cree's on order and will let you know how they perform. The Cree's may work better than the Luxeons for RC planes simply because of the wider cone of light. A disadvantage might be that there aren't any lense kits yet for the Cree's if you want a highly focused light beam.

[westfw]

Oh - I hadn't realized that All was selling new Cree LEDs; I had assumed some import clone. Hmm.

(newer luxeons are getting brighter as well.)

http://www.candlepowerforums.com has lots of info on everything light-related,
especially all the latest and greatest LEDs (including group buys, etc...)
5mm ultrabright LEDs tend to have rather limitted view angles. They make OK
flashlights, but lousy strobes...

[Marion]

Be careful !!

I have a tiny, black circle in the vision of my left eye from looking at a much less powerful LED :-(

Marion

[Warske]

Thanks for all the feedback.

Ram, I didn't know about the Luxeon V (5 watts).

Alain, your link to roithner-laser.com looks useful, especially as they say they ship international.

GeneSS, thanks for pointing out the efficiency difference. Are you getting your Cree chips from All Electronics, or a different source?

westfw, that's a great link to candlepowerforums.com

Marion, I'm sorry to hear about your eye, and thank you for the warning. Do you have any more information that could help others avoid a similar injury? Does it have to do with the color of the LED? How far away it is? How long you look at it?

Warske

[GeneSS]

Warske:

My first sample of Cree's came from AllElectronics. They are not "bin" marked in anyway that I can see, so I really have no idea exactly what I received. My initial tests show that the Cree's are superior to the Luxeon 1 watters, but no where near the 3X that their advertising and test data indicate. It is possible that the Cree's that AllE is selling (that I received) are lower "bin" rated chips. My tests show that the Cree's are developing about 25% more Lumens than the similar Luxeon 1 watt chips at the same input power. Yes, they are more powerful, but I am a bit disappointed.

[Warske]

...They are not "bin" marked in anyway that I can see... My initial tests show that the Cree's are superior to the Luxeon 1 watters, but no where near the 3X that their advertising and test data indicate. Thanks very much for the feedback.

That's interesting they aren't bin marked. I just looked at their data sheet and was surprised to see what a range of brightness there is depending on the bin.

As you mentioned in post #8, the Cree's emit a wider cone of light. I think they are quoting a viewing angle of 100 deg vs 60 deg for the Luxeon Star.

On the web (http://www.electro-optical.com/whitepapers/candela.htm) I found: The output from a lamp is usually quoted in lumens, summed over all directions...

This could mean that the Cree puts out 3x the light, but spread over a larger area, so the brightest spot might not be 3x as bright.

I don't know if you compared the brightest spot or used an integrating device for your measurements?

Warske

[GeneSS]

According to the specs, the Luxeon Star has a viewing angle of 110 degrees. This is "twice the off axis angle from the lamp centerline where the luminous intensity is 1/2 of the peak value".

The Cree has a viewing angle of 100 degrees.

I ran some more tests today and have attached a chart of the data. The Cree does have more output than the Luxeon, and runs cooler to the touch than the Luxeon at the same power levels. The Luxeon is "P" binned. Please note that these are both 1 watt leds. All of my data above 1 watt was acquired very quickly so as to minimize heating errors. Cree does give specs of max Vf = 4.0 volts and maximum current of 0.700 amps. My Cree was drawing 0.820 amps at 3.8 Volts. That's over three watts and I didn't push it past that point.

lux_cree.gif

[Acetronics]

Hi,

Those curves are a nice help, but, the problem is to compare devices from the same generations ...
Luxeon 1 are quite old, Cree very new ...
:confused: What about the 120 Lumens of Luxeon V , with 700 ma current ???
Seem to be very close to Cree's ...

Alain

[GaryRC]

I'm using ultra bright LED's to illuminate the wings and fuselage on one of my planes and it's working out nicely.(Thanks to the help I've gotten in the forum :D ) But there is still the problem of not seeing the ground when landing. (ouch!) Are the Cree's bright enough to illuminate the ground from about 20' in total darkness?
What I'd like to do is install one or two of them running off a dedicated 3 or 4 cell (650 mah). I'm also unsure of what to use for resistors on this. Any ideas?

[Acetronics]

Hello, Gary

:eek: Do you seriously think a Led could show you something at a , say, 50 meters ???
That's the distance you need to see the ground for a correct landing ... 5 seconds of flight, no more.

For that kind of sport, we always use ground lights along the lane , plus a long beam light to clearly show the plane attitude ...
Leds are here only for the show !!!

Your parrot has sniffed too much methanol ...

Alain

[sesat]

A Surefire head may make a better landing light?


Ram.

[Warske]

Are the Cree's bright enough to illuminate the ground from about 20' in total darkness? Depends on what you mean by illuminate. If you put one in a reflector, you could get it to dimly light up a spot on the ground at 20 feet, and this could help you judge distance from the ground for landing, especially if you used 2 of them and the beams are separated and pointed down. This could work if your landing area is large and flat and free of obstacles, and you can come in slowly (with a slow plane or using flaps). I can imagine this working very well on a Slow Stick, for example.

Essentially you would be designing a flashlight head, and Ram's suggestion is a good one.

The people at http://www.candlepowerforums.com that westfw pointed out are heavy into flashlights, and you could get ideas from there.

If your plane is electric, you should be able to save weight by taking power from the main battery.

To test your ideas, you might consider buying some small inexpensive flashlights and just taping them to your plane. Then you could turn them on and practice some night time touch and gos.

Warske

[GeneSS]

The Luxeon V's are not available in "white" yet, probably later this year. Also, the 700 ma rating on the Luxeon V's is at 6.8 vdc not 4 volts like the Cree. This is pretty close to 5 watts.

Also, the plain old Luxeon I Star works great as a landing light. I used it frequently last summer when flying my SlowStick at dusk or right after it got dark. I just switched it on using the 4th channel whenever I got ready to land. It illuminated the ground fine from about 5 ft elevation. I used a blue Luxeon to illuminate the bottom of one wing with mixed results. I finally just gave up on flying at night.

[GaryRC]

"Your parrot has sniffed too much methanol ..." Indeed it has. :D

Warske,

I do have a very large field to fly in with no obstacles. I want to try this on a Multiplex Easystar, which has a very slow glide. And yes, I only need to dimly light up a spot to give me at least an idea of where I am. I like your idea of inexpensive flashlights to try it out.

Thanks for the input guys. I'll let you know how it goes.

[jh2rc97]

http://www.futureelectronics.com/

for Lumileds. Many configurations and up to 5W LEDs.

[GaryRC]

"up to 5W LEDs" ! :eek:

Now we're talkin!

Thanks for the link jh2rc97.

[davekra]

Woohoo, I just got sample led's from xlamp.com . One each, white, and rgb. These are the 1 watt 350ma ones. They are on a 1" square die, kind of unusable but neat none the less.

Could someone help me find a circuit that would automatically dim an led up and down? I'd like to put the rgb ones behind some frosted glass and have the colors change constantly and infinitely.

Either that or does can anyone think of a cool application for some superbright led's?

Thanks,
davidk

[podavis]

Since I've lived for 23 years near the approach to Detroit Metro International it occured to me if the big boys only turn on their landing lights for landing, why not use a 12 volt halogen relector bulb and turn it on for landing? A 20W version in a landscape system lights up a substantial portion of a tall scotch pine. Imagine the awe it would invoke after switching that puppy on during your approach.

POD

[westfw]

The Luxeon V's are not available in "white" yet
Where do you get that idea? They seem to be ONLY available in the white-style
die (no red/orange/yellow, just blue, true green, cyan, white)

Pricey, though.

BillW

[sesat]

Gene, look for the "luxeon v portable".

[GeneSS]

I have stayed away from the Luxeon V portables because of the very short life as compared to the normal Luxeon V. The Lumileds site indicates that the Luxeon V's are available in white, but as a month ago I was having trouble finding actual distribution of this product. All of the places that I contacted had the colored versions in stock, but no white ones. I was told to expect to see the white version at the distributors later this summer. There are white Luxeons V's floating around, but so far, I have found that the normal distributors of the Luxeons are still waiting for the white ones to show up. Again this could change very quickly and may in fact have changed in the last month. Right now, I am trying to get my hands on the newest Luxeon K2's. This is the bad boy that I want to play with.

[Mikael Pedersen]

Could someone help me find a circuit that would automatically dim an led up and down? I'd like to put the rgb ones behind some frosted glass and have the colors change constantly and infinitely.

That should be no problem, as I have made such a circuit myself. I haven't tried it with Lumileds at full power, but that is just a question of a properly dimensioned driver transistor. Have a look here:
http://www.ejberg.dk/ledfade2/index.html

[davekra]

That should be no problem, as I have made such a circuit myself. I haven't tried it with Lumileds at full power, but that is just a question of a properly dimensioned driver transistor. Have a look here:
http://www.ejberg.dk/ledfade2/index.html

Now that looks cool! I was thinking too small!

Is the ball being suspended by the water being pumped in under it?

I checked out the way you made your circuit. At first I thought "maybe I can do a micro controller?" Then I did some more reading on the mega8 and realized I don't know that much about electronics to pull it off.
I did some searching and found something more my speed at http://www.solarbotics.net/library/circuits/bot_ornament_qlf.html
A nice analog circuit with a more easily understood theory of operation. I’ll need to figure out how to run 350mah through it but I think it will do what I want.

Thanks for the ideas, love your work.

[Mikael Pedersen]

Indeed the ball is carried only by the water.

If you haven't tried to use microcontrollers before at all, then it probably is a big step to take. The circuit you found, seem to do exactly what you want. And the 350 mA is again just a question of a large enough transistor :D