Oxygen Measurement Principles

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There are numerous sensor technologies to measure oxygen concentration. Two of the most common methods are polarographic and optical. This series of articles explores principles behind each method and finishes with a side-by-side comparison.

Diagram of a three-electrode electrochemical cell (W, R, C) with a voltage controller and polarization voltage labeled.
Principles of Polarographic Measurement
Diagram of a Clark-type dissolved oxygen sensor tip showing cathode, membrane, and O2 diffusion arrows.
The Membrane-Covered Clark Dissolved Oxygen Sensor
Sensor Output signal diagram
Sensor Output Signal
Optical dissolved oxygen sensor
Optical Dissolved Oxygen Sensors & Principles of Operation
Optical vs polarographic DO sensor comparison
Optical vs. Polarographic DO Sensors: Side-by-Side Comparison
Hamilton O₂ Measurement Guide cover featuring a Visiferm dissolved oxygen sensor submerged in water with bubbles and a data trend chart overlay

Download Our O2 Measurement Guide

Get a better understanding of O2 measurement in Hamilton’s comprehensive O2 Measurement Guide.