Re: "Full-spectrum" article on Wikipedia

"TKM" <nomail@xxxxxx> wrote in message
news:sO_8i.104789$p47.6789@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
[snip]

The Lighting Research Center has updated their original 2003
publication on
"full-spectrum" lighting to include a definition based upon an
equal-energy
source and they have an interesting way to calculate what they call
a
"full-spectrum metric".

Sorry, I should have looked at this report earlier and passed the
reference
along.

See:

http://www.lrc.rpi.edu/programs/nlpip/publicationdetails.asp?ID=887&type=2

Many thanks, Terry. Sounds like an interesting approach. I will see if
I can implement it in Maple and add it to the Engineering document, so
as to have an FSI objective as well.

First, I have to figure exactly how the FSI is calculated and what
they mean exactly by "a reference equal energy source" and I quote:

"In selecting an ideal light source as a reference, an equal energy
spectrum becomes the logical choice for two main reasons. First, the
SPD of an equal energy spectrum is, indeed, "full" across the entire
visible spectrum and, second, an equal energy spectrum is neutral with
regard to any prejudicial associations, positive or negative, with
"natural" light sources. Moreover, there are several electric and
natural light sources that have SPDs approximating an equal energy
spectrum, so choosing an equal energy spectrum as the reference
full-spectrum source is not entirely abstract or irrelevant.

Formally then, the proposed reference full-spectrum light source is an
ideal light source with equal energy across the visible region of the
spectrum, from 380 to 730 nm, inclusive. A new metric, called
full-spectrum index (FSI), based on this proposed reference..."

So, do you or anyone else have any idea what the spectrum of this
"reference equal energy source" should look like? Looks to me like I
should load a full spectrum from 380-700nm with all bin intensities
equal to 100, unless someone has a better interpretation. What say ye?

Terry McGowan
--
I.N. Galidakis --- http://ioannis.virtualcomposer2000.com/
----------------------------------------------------------
"There's ALWAYS a mistake somewhere"

.

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