Bio-Rad BioLogic QuadTec™ Detector and Components - Manual (Page 7)

1.1 USING THIS MANUAL
The instructions provided in this manual are for use of the QuadTec Detector with the following systems:
• The BioLogic DuoFlow chromatography system
• The BioLogic HR chromatography system
• Stand-alone use
1.2 OPTICAL PATH OF THE QUADTEC UV/VIS MULTI-WAVELENGTH DETECTOR
The light emitted from the lamp [1] is focussed by a lens [2] and a slit [4]. If a deuterium lamp is used and
wavelengths >380 nm are chosen, an automatic edge filter [3] is employed. The light passes to a grating
monochromator [6] for selection of the desired wavelength. The beam is then split by a semi-transparent
mirror [7]. Part of the beam passes to the photo diode reference signal [8] and optical absorption is
measured. The other part of the beam passes through the flowcell and sample and the light intensity is
measured at the sample photo diode [10]. The difference or the ratio of the two signals is calculated to
provide information about sample components.
Figure 1-2. Theory of Operations
INTRODUCTION SYSTEM OVERVIEW
1-2
1. LAMP (DEUTERIUM OR HALOGEN)
2. LENS SYSTEM (QUARTZ OPTICS)
4. SLIT
5. CONCAVE MIRROR
6. MOVABLE GRATING
MONOCHROMATOR
10. SAMPLE PHOTO DIODE
3. EDGE FILTER
7. SEMI-TRANSPARENT MIRROR
9. FLOW CELL
8. REFERENCE PHOTO DIODE