Shimadzu PDA-7000, Instruction Manual

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1 Configuration and Function of the Instrument
1-7
1.3 Spectrometer
The configuration of the spectrometer system is shown in the figure below.
Configuration of the spectrometer
The light coming out of the light source goes through the condenser lens and the
entrance slit, then diffracted by the diffraction grating and focused on the Rowland
circle based on each wavelength. Only the needed lines out of these spectra pass
through the exit slits, and enter the photomultipliers through the mirrors.
The entrance slit can be moved along the Rowland circle by the scanning dial, so
that the spectral line could be aligned correctly on the exit slit.
(1) Condenser lens
The condenser lens leads the light generated by the light source to the
spectrometer. At the same time, it serves as a partition between the vacuum in
the spectrometer and the outside air.
The condenser lens is made of fused quartz which allows the ultraviolet radiation
to easily pass through and is designed so that the light at 200 nm would be
focused on the diffraction grating surface.
(2) Temperature control circuit
To prevent the optical system deviation due to a temperature change, the
spectrometer is kept within a temperature range of 40

1°C by the temperature
control circuit.
Diffraction
Grating
Entrance Slit
Condenser Lens
Rowland Circle
Light Source
(Spark Stand)
Evacuation System Exit Slit Mirror Detector (Photomultiplier)