Sensor Technology

The miniDOT dissolved oxygen sensor is an optode that measures lifetime-based luminescence quenching of a thin membrane. The sensing foil, shown at right, contains a coating that has a variable fluorescence that depends upon oxygen concentration in the surrounding water.  The sensing electronics excites this membrane with a blue light of varying intensity and examines the phase relationship of the corresponding red light fluorescent emission. Oxygen concentration, in mg/L is computed by internal software based on the observed phase and from measurement of temperature also made concurrently by the sensor.  These values are recorded in text files on and internal SD card.

	Low power allows for longer sampling duration
	LED and sensing foil able to maintain calibration
	Fast measurement response
	Sensor is put "to sleep" after each measurement to conserve power.