Refractive Index Detector

In refractive index detector, the light beam undergoes a deflection in proportion to a difference in refractive index between sample side liquid and reference side liquid as it passes through the flow cell.

The deflection of the light beam is taken as a displacement on the light-receiving element (photo sensor) and is displayed as a difference of the refractive index.

Most of refractive index detector out in the market employ reference stop valve so called that suspends reference side liquid delivery to the cell during a measurement. A state of reference side liquid trapped in the cell should change over time and may affect a precision of measurement.