RADIOMETER ABL800 FLEX, Reference Manual

Page: 65 / 206

ABL800 FLEX Reference Manual 3. Optical measuring principles
Optical system,
Continued
Continuous
spectrum
n
A
λ
total
can be depicted graphically as a function of wavelength, and if the
differences between the wavelengths are small enough, a continuous spectrum is
produced.
EXAMPLES:
The figure below shows three spectra; pure O
2
Hb, pure HHb in a low
concentration, a spectrum of 92 % oxygenated hemoglobin obtained by adding the
spectra of O
2
Hb and HHb. The additivity of absorption and the continuity of the
spectra can clearly be seen.
480 500 520 540 560 580 600 620 640 660 680
O
2
Hb (9.2 mmol/L)
HHb (0.8 mmol/L)
92 % oxygenated hemoglobin (i.e., 92 % O
2
Hb + 8 % HHb)
Wavelength/nm
Absorption
Example of the spectrum obtained from unconjugated bilirubin at concentration of
200
µ
mol/L.
200u m o l/L U n co n ju g ated B iliru b in in P lasm a
0
0.02
0.04
0.06
0.08
0.1
470 520 570 620 670
nm
Ab
s
o
rb
a
n
c
e
The spectrum of conjugated bilirubin is slightly different.
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