The minimum allowable distance out from the sensor for reliable object detection. It is determined by a time period beginning when the transducer is energized, producing a sound wave, and when the resulting oscillations from that sound wave diminish to the point where it is possible for the transducer to accurately receive its echo. This space or "blind zone" in front of the sensor is not reliable for object detection. For Hyde Park ultrasonic sensors, the deadband can extend from 25 mm (1") to 120 mm (4.7") from the sensor, depending on the model selected.