Patent ID: 7615954
Filing Date: 2009-11-10
Classification: G01F

Abstract:
1. A system comprising: a plurality of ultrasonic transmitters; a plurality of ultrasonic receivers; control circuits coupled to the transmitters and the receivers; first and second solid state switch elements coupled to the control circuits; first and second load ports, one of the switch elements can conduct a varying current in one direction relative to the ports, the other switch element can conduct a varying current in the opposite direction relative thereto; and where the control circuits evaluate signals from at least some of the ultrasonic receivers relative to enabling at least one of the switch elements to enter a conducting state; where the enabling includes respectively enabling one of the switch elements at a time to enter a respective conducting state; where the conducting states each define a different current flow path; where the control circuits activate at least selected ones of the transmitters, the activated ones of the transmitters emit ultrasonic signals; where ultrasonic signals emitted by the selected ones of the transmitters are incident on at least some of the receivers; and where at least some of the receivers couple indicia corresponding to incident ultrasonic signals to the control circuits.