Waters ACQUITY Refractive Index Detector Overview And Maintenance Manual page 18

1 The ACQUITY Refractive Index Detector
Measuring refraction
The extent to which a beam of light undergoes refraction when it enters a
medium depends on these properties:
• The angle at which the light enters a changed medium (the angle of
incidence)
• The refractive indices of the old and new media
The following figure illustrates the relationship between the angle of
incidence, angle of refraction, and refractive index.
Refraction of light:
Incoming light beam
Angle of refraction
18 October 13, 2014, 715003547 Rev. C
Angle of incidence
θ
1
Medium 1, RI - n
Medium 2, RI - n
Refracted
light beam
θ
2
1
2