Abstract: A zoom lens with a slim and compact design has arranged in sequence from the object side to the image plane side a first lens group having a negative refractivity, a second lens group having a positive refractivity, and a third lens group having a positive refractivity. The first lens group is formed from a first lens having a negative refractivity and a second lens having a positive refractivity. The second lens group is formed from a third lens having a positive refractivity and a fourth lens and a fifth lens. The fourth and fifth lens are joined together and have a negative refractivity. The third lens group is formed from a sixth lens having a positive refractivity. The zoom lens has a short length when retracted and extended, and a design that is compact and thin.

Abstract: Two-dimensional distribution data of velocities on a moving object in an object to be examined is obtained. A motion field which defines the motion direction of a tissue is stored. A plurality of tracking points are obtained in a tissue range in the two-dimensional distribution data. The moving positions of the tracking points are estimated and the positions are sequentially tracked. Velocities toward the motion direction defined by the motion field are obtained on the basis of the two-dimensional distribution data. One intermediate output value is obtained by performing a predetermined computation by using velocities toward the motion direction at tracking positions of at least two tracking points in each time phase. The values of intermediate positions are obtained by performing weighted addition of intermediate outputs at different positions. A display image is generated and displayed by using the values of the intermediate positions.

Abstract: A three-dimensional ultrasonic diagnostic apparatus includes a two-dimensional array type of ultrasonic probe. A three-dimensional scan operation of scanning a three-dimensional region within a human body under examination with ultrasound and a two-dimensional scan operation of scanning a two-dimensional plane within the three-dimensional region with ultrasound are selectively performed by a beam former unit. Under the control of a controller, the three-dimensional scan operation is repeated intermittently and the two-dimensional scan operation is repeated during the interval between each three-dimensional scan. Three-dimensional ultrasonic image data concerning the three-dimensional region is produced on the basis of received echo signals obtained by the three-dimensional scan operation. Two-dimensional ultrasonic image data concerning the two-dimensional plane section is produced on the basis of received echo signals obtained by the two-dimensional scan operation.

Abstract: An ultrasound diagnostic apparatus including transmitting and receiving devices, and MTI filter units to eliminate clutter components from Doppler data sequences detected trough the transmitting and receiving devices. The diagnostic apparatus further includes A/D converters to convert the Doppler data sequences in analog to those in digital and transient response processing devices provided between the MTI filter units and the A/D converters to suppress influences of transient responses consisted in output signals of the MTI filter units due to at least either one of data discontinuity of the Doppler data sequences at the time starting point or abrupt changes thereof.

Abstract: An ultrasound diagnostic apparatus having an ultrasound probe, a device for transmitting ultrasound to an subject through the ultrasound probe to receive echoes from the subject, a spectrum processor for approximating a spectrum of each of the echoes to a predetermined shape, and a unit for reconstructing an ultrasound image based on an output of the spectrum processor. The spectrums of the echoes are distorted by various reasons. There is a method for correcting a spectrum by enhancing only a high-frequency component of the echoes. Since this method is no more than to consider one reason, i.e., only frequency dependence of attenuation, a suitable correction cannot be made. According to the present invention, the spectrum is approximated to the predetermined shape, therefore the distortion of the spectrum caused by various reasons can be suitably corrected.

Abstract: An ultrasound beam is repeatedly transmitted and received to and from an object, so that an echo signal is repeatedly obtained. A velocity of each of a plurality of portions on the ultrasound beam is calculated based on the echo signal. A position of at least one specific portion of the plurality of portions is tracked in as it changes with the passage of time based on the velocity to obtain a path where the specific portion moves. Conventionally the change of brightness of the M-mode image was tracked to obtain the path. According to the present invention, since the path is obtained based on the velocity having high resolution, the accuracy of track can be improved.

Abstract: A reception signal containing phase information and amplitude information is obtained by scanning a cross section of a subject with an ultrasonic wave. An ultrasonic image is formed on the basis of the reception signal and displayed. A noise component is filtered from reception signals at respective points in the cross section. The reception signals, which have not been non-linear processed, i.e., have not been subjected to an image forming process, are filtered. Therefore, the suppression effect of suppressing an image of a portion which moves at a relatively low speed and the emphasis effect of emphasizing an image a portion which moves at a relatively high speed can be improved as compared to the conventional art in which an ultrasonic image after non-linear process is filtered.

Abstract: There is disclosed an ultrasonic diagnosis apparatus comprising a transmission/reception unit, a signal processing unit, a conversion unit, and a display unit. The transmission/reception unit transmits/receives ultrasonic waves to/from an object to be examined, thereby obtaining ultrasonic reception signals. The signal processing unit executes signal processing of the ultrasonic reception signals to obtain ultrasonic images. The conversion unit converts an ultrasonic image having a predetermined dynamic image obtained from the object to be examined to which a contrast medium is injected into an ultrasonic image having a dynamic range corresponding to that of the display unit. The display unit displays the ultrasonic image obtained by the conversion unit.

Abstract: A single crystal of semiconductor silicon can be sliced into wafers not by the conventional mechanical means but by a novel chemical means so that advantages are obtained in the reduced material loss by cutting and in the absence of any mechanically stressed layer in the surface of the wafer as sliced. The method comprises conducting electrolysis of an aqueous solution containing sulfuric and hydrofluoric acids with a fine platinum wire as the anode to evolve oxygen containing ozone on the anode surface while a single crystal of silicion is held in proximity to the wire anode so that the nascent oxygen formed from the ozone oxidizes silicon into silicon dioxide which as formed is dissolved away in the acidic medium to leave a groove in the single crystal. When the wire anode or the single crystal is continuously moved to keep a small distance between the wire anode and the groove bottom, the whole single crystal body is cut through to form a wafer.