Ultrasonic transmitter and receiver with compliant membrane

An ultrasonic imaging system comprising:

• an ultrasonic transmitter and receiver comprising:
• a MEMS composite transducer comprising
• a substrate, portions of the substrate defining an outer boundary of a cavity;
• a first MEMS transducing member including a first size, a first portion of the first MEMS transducing member being anchored to the substrate, a second portion of the first MEMS transducing member extending over at least a portion of the cavity, the second portion of the first MEMS transducing member being free to move relative to the cavity;
• a second MEMS transducing member including a second size smaller than the first size, a first portion of the second MEMS transducing member being anchored to the substrate, a second portion of the second MEMS transducing member extending over at least a portion of the cavity, the second portion of the second MEMS transducing member being free to move relative to the cavity;
• and
• a compliant membrane positioned in contact with the first and second MEMS transducing members, a first portion of the compliant membrane covering the first and second MEMS transducing members, and a second portion of the compliant membrane being anchored to the substrate;
• a first electrical circuit connected to the first MEMS transducing member;
• and
• a second electrical circuit connected to the second MEMS transducing member.