Horiba Scientific Quanta-phi F-3029, Operation Manual

Page: 26 / 98

Quanta-
φ
rev. C (23 Apr 2010) Theory of Operation
1-12

The resultant sample power spectrum is then used to calculate three sum-product
values, namely, CIE_TX, CIE_TY and CIE_TZ, from the observable intensity spec-
tra xBar, yBar and zBar, respectively.
For the CIE 1931 index, the following two coordinates are calculated,
The coordinates
x and y are plotted graphically inside the CIE 1931 boundary area,
which is defined numerically for the x coordinate at each wavelength value,
λ
,


  
and for the
y coordinate at each wavelength value,
λ


  
where xBar
λ
, yBar
λ
and zBar
λ
are the intensity values from the three observable profiles
at wavelength
λ
. The corresponding xBA
λ
and yBA
λ
values are plotted against each
other to generate the semielliptical two-dimensional area-boundary plot for CIE 1931
(blue, left) as shown in the sample plot for rhodamine 101 in anhydrous ethanol in the
screenshot on the next page.
For the CIE 1976 index, two coordinates are calculated as follows:
The coordinates
u
′ and
v
′ are plotted graphically inside the CIE 1976 boundary area,
which is calculated from the xBA
λ
and yBA
λ
values for the u
′ coordinate at each wave-
length value,
λ
,


 
and for the
v
′ coordinate at each wavelength value, λ