How The Echelle Spectrometer And Scd Work; Introduction; Transfer Optics; Input Module - PerkinElmer AVIO 500 Customer Hardware And Service Manual

System Description
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How the Echelle Spectrometer and SCD Work

Introduction

The Avio 500 optical design combines an echelle polychromator with a solid-state
detector in an integrated system optimized for ICP-OES. The echelle
polychromator produces a compact two-dimensional spectrum that is focused onto
the solid-state detector. The Segmented-array Charged-coupled device Detector
(SCD) simultaneously measures emission lines for the analytes and the spectral
background. On the silicon surface of the detector is a collection of linear detector
segments strategically located to measure the most important ICP emission lines.
Random access to data for individual emission lines ensures rapid analysis.
The Avio 500 is a dual detector system. The UV detector covers an extended
ultraviolet wavelength range from 165 to 403 nm. The VIS detector covers the
visible wavelength range from 404 to 782 nm.
The optical system consists of the transfer optics, input module, and UV module
and a VIS module.

Transfer Optics

The torch emission is directed to the entrance slit by the transfer optics. A
computer-controlled toroidal mirror can be rotated both vertically and horizontally.
This computer-controlled movement allows the user to adjust the viewing height
and the viewing position. For more information on the transfer optics, see the
diagrams for radial and axial view Figure 3-2 see page 80 and Figure 3-3 page 81.
An automatic shutter mechanism (not shown in optical diagrams) minimizes the
UV exposure on the first toroidal mirror and the rest of the optical system thus
extending its useful lifetime. The shutter mechanism also includes a mercury pen
lamp. This pen lamp can be used to check the wavelength calibration of the system.

Input Module

The input module consists of three components: the computer-controlled slit
mechanism, the parabolic collimator mirror and the echelle grating. The slit
mechanism contains three slit openings: the "High Resolution" slit, the "Normal
Resolution" slit, and the "Low" (High Energy) slit. After the light from the plasma