In-line process refractometers

for industrial process instrumentation and control applications. 

We offer a range of products based on refractometer technology meeting the liquid measuring needs of different industries. 

Choose industry

Food & beverage

Pharmaceutical & biotechnology


Chemicals and allied


Pulp & paper

Oil & gas refining & petrochemicals

Sweeteners and sugar substitutes

Watch the video

Tutorial video to LM web pages

Video guide

to the new dedicated Liquid Measurements pages on!

Explore all useful resources on Liquid Measurements topics:

  • application notes and whitepapers
  • product news and videos
  • helpful articles and eBooks
  • and much more

Or check out the same information from the brochure.

Library of downloads and software

Here you will find product manuals, approvals and test certificates, material safety data sheets (MSDS) and software for connectivity and communications.

What is process refractometer

Vaisala K-PATENTS® Process Refractometers are used for in-line liquid concentration measurements enabling advanced and accurate process control supporting industrial automation.

Learn more about the principle, technology, and measurement behind a refractometer; refractive index.

Frequently asked questions

Here you will find answers to the most typical questions regarding the process refractometer.


Vaisala and our authorized Liquid measurements distributors offer comprehensive customer care covering the entire lifecycle of Vaisala K‑PATENTS refractometers, and provide application support. See our refractometer service offering from this page.