red leds

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aceez71
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red leds

Post by aceez71 »

I am looking for some red light emitting diodes. I need a wavelength of 680nm can anyone guid me in the right direction.Thanks
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Dave Dixon
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Re: red leds

Post by Dave Dixon »

Digi-Key, Mouser, Newark-In-One, Chicago Miniature, Ledtronics, Allied Electronics to name a few.
Can you be a little more specific? Surface mount? Through hole? Diffused or Clear, Round or Rectangular? Quantity required?
Good luck,
Dave
BTW 700nm seems more common..
Is that close enough???<p>[ December 02, 2004: Message edited by: Dave Dixon ]</p>
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Chris Smith
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Re: red leds

Post by Chris Smith »

680 NM is closer to the IR spectrum, than the visual.

640 is the typical RED led.
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philba
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Re: red leds

Post by philba »

I agree with the other posters, please be more specific. Particlularly, what is the application? With out this its basically impossible to help you other than pointing you to the obvious places.<p>Things to consider when selecting LEDs: color (wavelength), brightness (candella rating), power consumption (If, Vf too but red is usually about 2V), size and shape (many many many to choose from), mounting, viewing angle (lens focus), diffused/clear. did I forget anything? Needless to say, this is a lot more complex than one would think... And I haven't even broached driving methods.
aceez71
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Re: red leds

Post by aceez71 »

680nm is the only requirment that i have the other parameters could be anything you name it!!!! Again 680nm is all you need to know. Thanks
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Chris Smith
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Re: red leds

Post by Chris Smith »

What’s your plus or minus parameter?
aceez71
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Re: red leds

Post by aceez71 »

for this application it needs to be exact which may be none existing?
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Chris Smith
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Re: red leds

Post by Chris Smith »

Example <p>http://ledmuseum.home.att.net/ledred.htm<p>Unfortunately, LEDs have a wide spectral response, and its never exact. <p>For that you have to go Laser, and then the NMs are down to plus or minus two or three.
aceez71
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Re: red leds

Post by aceez71 »

Have you ever heard of a 680nm led by design anyway? Some said they read an articale about one but i have yet to find one myself.
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dacflyer
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Re: red leds

Post by dacflyer »

Hmmm , wonders what they will be used for..
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Re: red leds

Post by Engineer1138 »

Some kind of colorimetry or absorbtion measurement would be my guess, but the OP seems unwilling to share more info. <p>Anyway, if he's that set on a particular wavelength he might be better off with a white LED and a precision color filter.<p> <blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by dacflyer:
Hmmm , wonders what they will be used for..<hr></blockquote>
aceez71
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Re: red leds

Post by aceez71 »

Thanks for the pointers guys i am going to do a little more research and i will get back to you all
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Chris Smith
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Re: red leds

Post by Chris Smith »

You need to check out the specially or exoticly "doped" LEDS. <p>They add in small trace elements to increase the current flow, while either gaining a color shift, or out put intensity from this process. <p>The only places to look for these types of Led, or at least the info, is the universities [web pages] in China, Japan, India, Germany and the US. The Japs and Germans seem to have the most. <p>Phillips, Siemens [AG] group, and Hitachi might be a good starting point also?
aceez71
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Re: red leds

Post by aceez71 »

chris you have been a great help thanks again
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philba
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Re: red leds

Post by philba »

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>
...The Japs and Germans seem to have the most.
<hr></blockquote><p>sorry if I sound politically correct but could we not use racial slurs around here? even innocently. Some of us take offense to that term.<p>Phil
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