We set the measure
Measuring method
Comparison with alternative methods


The determination of the refractive index (critical angle of the total reflection) is a proven laboratory method for the determination of concentration or density using various calibration charts.

The refractive index will be determined with an optical window. Several disadvantages result for process applications using a refractometer:
  • Coating on the window surface generates a drift of the values or prevents the application completely.
  • The design requires a gasket or glued joint. Both can be corroded while using such instruments in aggressive processes.
  • Parts of the electronics (CCD-line) require a Peltier cooling. Such chillers have a limited life time.
  • The refractive index depends on the wave length of the light source.
  • Literature based on refractive index charts or calibration charts of lab devices will not be suitable for the calibration of process devices.

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