Horiba Scientific Quanta-phi F-3029, Руководство по эксплуатации

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Quanta-
φ
rev. C (23 Apr 2010) Theory of Operation
1-11
Calculation and evaluation of chromaticity
Theory
The Quanta-φ software automatically
calculates and presents the numerical
and graphical coordinate information
for the spectral region (
E
c
– E
a
) deal-
ing with the chromaticity observable
indices CIE 1931 and CIE 1976. The
chromaticity indices provide a means
for comparing the observed color (or
tint) of the luminescence relative to
the human visual perception of color.
As displayed in the figure on the
right, relative to the CIE 1931 index
plot, the boundary area outlines all
potential hues visible to the human
eye.
The chromaticity indices are based on
the overlapping regions of the norma-
lized luminescence emission spectrum,
with each of the three spectral profiles
depicted in the figure on the right.
The regions of spectral overlap for the
luminescence emission spectrum is eva-
luated by calculating the sum-product
of the emission spectrum with each of
three observable profiles, namely, xBar,
yBar and zBar. The observable profiles
are related to the three visual sensory-
cell responses in the human eye, namely, the red (xBar), green (yBar) and blue (zBar).
Note that the red profile also includes a portion of the blue spectral region.
Calculations
The Quanta-φ calculations for CIE 1931 and CIE 1976 proceed as follows.

First the emission spectral regions from 360 nm–800 nm for E
c
and E
a
are interpo-
lated to 1-nm intervals, and the spectral curve of the blank ( E
a
) is subtracted from
the sample ( E
c
).

Then the resultant blank-subtracted sample spectral profile is converted from pho-
ton units to power units, by division of each intensity point by the wavelength value
in nm at which it was measured.
Line of purples
Blue
apex
Red
apex
Green
apex
White