Apparatus for two-dimensional transducer used in three-dimensional ultrasonic imaging
A single chip transducer apparatus that includes on-chip electronic circuitry which, when connected properly to a two-dimensional matrix of ultrasonic transducer elements, provides enough information to an external imaging system to form three-dimensional images of the subject of interest. In a preferred embodiment, the circuitry provides an amplifier for each transducer element, and then conditions the output of the amplifier in several ways. In one embodiment of the invention, the elements' analog voltages are stored in a sample and hold circuit, and time multiplexed into a high speed line driver that sends many elements data down the interconnect to the system's high speed Analog to Digital converters. In another embodiment, the gain of the amplifiers can be controlled in time to provide aperture translation and time based expansion for translating and focusing image slices in the elevation direction.
1. An apparatus for providing analog ultrasonic imaging data signals for three-dimensional imaging, the apparatus comprising: a chip; a transducer array having a plurality of transducer elements that forms part of the chip, each receive element adapted to produce received analog ultrasonic signals on a signal line; a plurality of conditioning circuits adapted to provide signal conditioning to the received analog ultrasonic signals to produce conditioned analog ultrasonic imaging data signals, each conditioning circuit forming another part of the chip, being disposed substantially below the transducer element associated therewith; and an adder that sums at least two of the conditioned analog ultrasonic imaging data signals.
2. The apparatus of claim 1 wherein: the plurality of conditioning circuits are grouped into a plurality of sets; each of the plurality of sets is an elevation group, each elevation group formed in an elevation direction and arranged adjacently in azimuth, each of the plurality of elevation groups including at least two of the receive transducer elements; the adder is a plurality of adders that each sum the conditioned analog ultrasonic imaging data signals of the set; adjacent receive transducer elements of different elevation groups form a plurality of azimuth groups; one or more of a plurality of elevation control lines are coupled to conditioning circuits associated with the receive transducer elements of each azimuth group; and the conditioning circuits of each azimuth group are controlled by a signal transmitted over a corresponding one of the plurality of elevation control lines.
3. The apparatus of claim 2 , further including: means for electronically translating the azimuth groups of the transducer array to form an active aperture adapted to collect image data capable of rendering a 3-d image; and means for elevation focusing the transducer array.
4. The apparatus according to claim 3 , wherein the means for electronically translating and focusing includes: means for controlling a gain in time of a low noise and variable-gain amplifier stage for each of the conditioning circuits.
5. The apparatus according to claim 4 , wherein the means for elevation focusing the transducer array includes means for varying the gain in time from a short-range apodize pattern to a long-range apodize pattern in a manner correlated with a speed of sound in a medium of interest.