Ultrasonic imaging method and ultrasonic imaging apparatus

An ultrasonic imaging apparatus for obtaining image information in such a manner that a predetermined area contained in an object to be inspected is divided into at least a first area located most shallowly and a second area located deeper than the first area so as to scan the first and second areas by employing ultrasonic waves, said ultrasonic imaging apparatus comprising:

• drive signal generating means for delaying input signals to supply drive signals having specific phases, respectively;
• an ultrasonic probe having a plurality of ultrasonic transducers, for transmitting ultrasonic waves in accordance with the drive signals and for receiving ultrasonic waves to output detection signals based upon the received ultrasonic waves;
• signal processing means for processing the detection signals to obtain image information of an object to be inspected on the basis of the processed detection signals;
• and
• control means for controlling said drive signal generating means and said signal processing means to (a) transmit and receive ultrasonic waves focused in one focus direction within the first area by using said plurality of ultrasonic transducers to take samples of an ultrasonic image at a plurality of points in the focus direction, and change the focus direction to scan the first area and (b) sequentially transmit ultrasonic waves focused in respective focus directions within the second area by using said plurality of ultrasonic transducers in a predetermined time period, thereafter receive ultrasonic waves reflected from the respective focus directions by using said plurality of ultrasonic transducers to take samples of the ultrasonic image at a plurality of points in the respective focus directions.