Convenience and accuracy? With no membrane replacement, no electrolyte replacement, no incoming flow required, and no hydrogen sulfide interference, optical dissolved oxygen portable meters are winning over fans. The meters also offer a short response time, minimal drift, and minimal maintenance.
measures the peak height of luminescence. Accuracy degrades over time as the sensor degrades due to photo-bleaching; frequent calibration is required for this method.
measures the decay rate of luminescence. Signal-to-noise ratio can limit the sensor range in this method.
(phase detector) measures the phase difference based on the entire signal and reference wave forms across a population of pulses. This method delivers the highest accuracy over the widest operating range and is commonly used.