Hi Paul,

Yeah and the spec sheets are often not correct.

typically some manufactures over state their specs by several factors in some
cases, particularly some from China. so I have my LEDs tested and go by those
specs instead of the spec sheet in relation to actual output.



Take care,
V


> Thanks for the clarification, looking at those spec sheets is very
> confusing.

> -----Original Message-----
> From: LEDeffects@yahoogroups.com
> [mailto:LEDeffects@yahoogroups.com] On
> Behalf Of V
> Sent: Friday, February 13, 2009 12:38 PM
> To: Paul Strouth
> Subject: Re: [LEDeffects] wich type of LED necessary for phototherapy
> treatment for skin rejuvenation

> Hi Paul,

> those are nice LEDs I have some of them. but the 500 mw figure is not
> the output of the LEDs that is how much energy they can dissipate
> basically and does not indicate their output. I think lots of
> manufacturers might use that figure to tell the output of their LEDs.
> At the most those 10 mm LEDS might put out 30 mw, but probably more like
> 15 to 20.

> For red 5 mm LEDs you might get around 6 to 7 mw output, blue ones con
> put out around 14 mw, infrared ones at 880 nm put out around 6 and ones
> around 850 can put out about 12 to 14 mw

> So if you see figures up there in the triple digits for 5mm LED output
> they are bogus. A plastic LED can't put out that much without burning
> up.

> I send most of the LEDS I use to somebody that has a machine that
> measures the actual output of the light. And those are the figures I get
> back.

> So when you read various websites with them telling you they have high
> figures for the output you better check close what numbers they are
> publishing. the dissipation figure is not the output, that is how much
> energy the LED can dissipate in heat and light without it burning up.
> And if you put a bunch of LEDs together in an array the figure changes
> because now to dissipate that much you have to put fans on there to
> remove the heat. Or run them for only a short amount of time.


> Take care,
> V


>>
>>
>>
>>
>>
>>
>>
>> Here?s a link for 10mm leds they are 130,000mcd, 500mw and at
>> 620nm. It?s an ebay store called shop4leds. I bought some of these and
> they are super bright.
>>
>>
>>

> http://cgi.ebay.com/10-PCS-10mm-40-5-Chips-0-5-Watt-Red-LED-100mA-150Kmc
> d_W0QQitemZ220285088384QQihZ012QQcategoryZ66954QQtcZphotoQQcmdZViewItemQ
> Q_trksidZp1742.m153.l1262
>>
>>
>>
>>
>>
>>
>>

>>
>>
>> From: LEDeffects@yahoogroups.com
>> [mailto:LEDeffects@yahoogroups.com] On Behalf Of fredericjulien13
>> Sent: Friday, February 13, 2009 9:42 AM
>> To: LEDeffects@yahoogroups.com
>> Subject: [LEDeffects] wich type of LED necessary for phototherapy
> treatment for skin rejuvenation
>>
>>
>>
>>
>>
>>
>>
>> hello,
>>
>> I need to create a device for phototherapy for skin treatment.
>> I've seen many on internet but the values given in technical
>> caracteristics are strange and seems unreachable like in the siloueth
>> tone device:
>> http://www.silhouet-tone.com/product/specialized/soli-tone-
>> 2500/soli-tone1.html or the Omnilux revice:
>> http://www.phototherapeutics.co.uk/index.asp?AccessID=&sectionID=15
>>
>> they give an output of 105 mW/cm2 in red 630 nm ? but, it seems that
>> they use 5mm LED but even with the brightest I've found I connot
> reach
>> that level. to reach such level I have to use High power LEd like
>> LUXEON K2 but the heat dissipation is a real problem.
>>
>> did someone know what kind of LED are used for those application.
>>
>> best regards
>>
>>
>>
>>

>>
>>

> --



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