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Chapter 2 Function
2.1 Optical System
Figure 2-1 is the schematic diagram of FL970 optical system. The light source is 150W
xenon lamp. Ozone generated is sealed by the structure of the light source chamber and can be
decomposed by the heat generated. The bright spot of the xenon lamp is magnified by the
ellipsoidal lens, focused and directed to the entrance slit on the excitation side by the dichroic.
The light beam is diffracted and focused by the grating and a narrow band of the spectrum will
pass through the exit slit and then reaches the sample cell.
The monochromator is holographic type that consist of a concave diffraction grating and a
slit components. Part of the excitation light beam is split by a beam splitter is reflected by a
quartz plate and enter the photomultiper for monitoring. Light emitted from sample cell will be
focused by a focusing mirror and then enter the monochromator, which is consist of a slit and a
concave diffraction grating. The fluorescence light will enter the photomultipler for detection
of signal intensity via a reflector
Figure 2-1 Schematic diagram of FL970 optical system
2.2 Theory
FL970 consists of lamp, EX monochromator, sample chamber, two photoelectric conversion
components, control circuit, data circuit and independent PC system (Figure 2-2).