Detection Principle - Agilent Technologies Infinity 1260 User Manual

Detection Principle

Detector Design
The Agilent 1260 Infinity Refractive Index Detector is a differential
refractometer that measures the deflection of a light beam due to the
difference in refractive index between the liquids in the sample and reference
cells of a single flow cell.
A beam of light from the lamp passes through a flow cell which is separated
diagonally into sample and reference cells. At the rear of the flow cell a mirror
reflects the light back through the flow cell and via a zero glass, which affects
the path of the light beam, to the light receiver. The light receiver has two
diodes each of which produces an electrical current proportional to the
amount of light that falls upon it (see
Agilent 1260 Infinity RID User Manual
Introduction to the Refractive Index Detector
Figure 3 on page 14).
Detection Principle
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