Agilent Technologies Infinity 1260 - How the Detector Operates

Agilent 1260 Infinity RID User Manual 11
Introduction to the Refractive Index Detector
1
How the Detector Operates
How the Detector Operates
Refractive index When a beam of light passes from one medium into another, the wave velocity
and direction changes. The change in direction is called refraction. The
relationship between the angle of incidence and the angle of refraction is
expressed in Snell's Law of refraction.
Where:
• n = Refractive index of medium 1 relative to medium 2
• n
2
= Refractive index of medium 2
• n
1
= Refractive index of medium 1
• α
1
= angle of incident light in medium 1
• α
2
= angle of refraction in medium 2
Figure 2 Light Refraction
Medium 1
Medium 2