The CONTROS HydroFlash® O2 optode is a versatile subsea, shallow and deep-water oxygen sensor which can be used for autonomous deployments as well as integrated into sensor systems. The CONTROS HydroFlash®
O2 is designed for a wide variety of deployment schemes and platforms including but not limited to AUVs, gliders, floats, water sampling rosettes, buoys, and moorings.
Individual 'in-situ' calibration
The optode head has a unique design featuring an anti-fouling head, a fast response temperature probe and a curved glass substrate coated with the sensing membrane. All sensors are individually
calibrated in a water tank over a wide range of temperatures and oxygen concentrations. An established laboratory method ('Winkler test') is used to ensure the quality of the calibration.
The advanced, optical sensor is based on the principle of fluorescence quenching. Dissolved oxygen (O2) molecules diffuse into a membrane in which a fluorescent dye is embedded. Oxygen is capable
of quenching this fluorescence by transferring the excitation energy from the dye to the O2 molecule. The sensor repeatedly excites the dye in the membrane and measures the intensity and phase shift
of the fluorescence light. The more O2 is present in the water, the smaller is the measured fluorescence signal and the higher is the phase shift.