Natural light Vs. White LED's

[horrorsix]

I would like to know the difference between natural light and a white LED.

I know white LED's cover a spectrum from 420nm to 700nm. I also know that sun light goes beyond that into the infra red and ultra violet. But if we just focus on the 420nm-700nm spectrum is there a difference between natural sun light an a white LED's?



Thank You

 

[yellow]

there are several differences (only apply when the led is a high power one, those 5mm are no-nos)

* green, brown, orange, ... and such colors, are quite "real" with hotwires/sunlight, a white led gives more or less funny colors but You get used to this
* the more the light goes to white/blue, the more the brain tells You that this light is more bright, even if it is not.

But led and their output are this powerful while consuming much less current now, that the pros are worth the cons.

 

[Ken_McE]

I would like to know the difference between natural light and a white LED....if we just focus on the 420nm-700nm spectrum is there a difference between natural sun light an a white LED's?

Yes, there is a good deal of difference. Our eyes are closely attuned to the light output of the sun. If you are familiar with CRI (Color rendition index) you will know that natural sunlight is defined as having a CRI of 100, which means that we can see all colors clearly and acurately by its light. Many white colored lights are guaranteed to have a certain CRI number. The higher the number the more acurately you can see things by it, the lower the number the more it will throw off our perception. For every day walking around purposes you don't need a high CRI. If you work with things where accurate color or clear detail is important you will start to need high-CRI lights. A cool white LED won't have a very high CRI number. It will have a lot of blue in its light and be somewhat weak at showing reds and greens.

 

[horrorsix]

Thank you very much.

Is there a chart showing the wave length peaks of natural light available on line.

and

Is a full spectrum LED the same as a white LED, natural LED or neither.

 

[betalight]

White led spectrum:
http://en.wikipedia.org/wiki/Image:White_LED.png

Daylight spectrum:
http://home.twcny.rr.com/geomanagement/ensmingr/spectrum.html

There are no full spectrum leds that I'm aware of but you could get pretty close with tricolor leds.

 

[horrorsix]

Thank you. That's exactly what I'm looking for.

 

[leap]

Why are large leds superior to 5mm ones? Do manufacturers use better phosphors on the larger leds or is it due to their intrinsic qualities (surface area, brightness)?

 

[Cypis]

Even "Pure white" (as opposed to "white warm") or "Sun light" led's can have quite different spectrums, CRI and colour temperature, see:

http://www.cree.com/products/pdf/XLamp7090XR-E_B&L.pdf (page 3)
http://www.essc.co.kr/_HOMEPAGE/home_kor/product/spec/BL25.pdf (page 13)
http://www.seoulsemicon.co.kr/_homepage/home_kor/product/spec/W42180.pdf (page 5 - spectrum)

According to above, Seoul "Sun white" led's can have colour temperature from 3500K to 4500K, and other "white" leds have even more different light.