Abstract: A device for the destruction-free testing of components, in particular of concrete components with ultrasound is suggested, which comprises at least one sensor module with several ultrasonic testing heads functioning as transmitters and/or receivers. The sensor module is provided with a device for producing transmitter impulses for the ultrasonic radiation and with a device for acquiring the readings. Several sensor modules for forming an array are mechanically connected to one another. Furthermore, a control- and evaluation device for activating the sensor modules with their ultrasonic heads and for evaluation of the readings delivered by the sensor modules is provided, which via a bus system is connected with control- and data leads to the sensor modules.

Abstract: Systems and methods to obtain an ultrasonic image of a large detection area are disclosed. A system includes a source of ultrasound generating ultrasonic energy and projecting the ultrasonic energy from a projecting end and an adapter interfaced to the projecting end and ultrasonically coupling the source of ultrasound to a first surface of the structure to be imaged at an adjustable angle of incidence. A method includes ultrasonically coupling a source of ultrasonic energy to a first surface of a structure to be imaged with an adapter, the adapter adjustable to a select a first angle of incidence and a second angle of incidence, projecting ultrasonic energy into the structure, and detecting a reflected acoustic energy from the structure with an ultrasound camera. A first angle of incidence is selected to introduce a longitudinal wave into the structure, and a second angle of incidence is selected to introduce a shear wave into the structure.

Abstract: Provided is a multi-line beamformer (100) that generates a multi-line output (141-144) by positioning multiple receive beams within the area covered by a transmit beam. N multi-line beams are generated using N/M fully capable beamformers (111-116) by producing partial sums (121-128) from sub-groups (105-108) of the elements of the beamformers (111-116), where M depends upon a per channel element spacing measured in wavelengths of the imaging frequency.

Abstract: Ultrasound is used to detect either or both the opening of a door of a shipping container or a change in the contents of a shipping container. Ultrasound signals transmitted from one or more ultrasonic transducers configured to be mounted within an interior of a shipping container travel through the interior and are reflected by a reflector, e.g., a corner reflector. The reflected ultrasound is received by an ultrasonic receiver, which produces an output signal corresponding to the received ultrasound signal. If the ultrasonic transducer or the reflector is mounted on the door, the time of flight of the ultrasound signal can be used to determine the distance that the ultrasound signal travels. Opening the door changes this distance, which can be detected. Similarly, changes in ultrasound reflected from contents in the shipping container can be detected and used to detect changes in the contents, which may be caused by terrorist activity.

Abstract: The present invention relates to a device for guiding the movement of a transducer of an ultrasonic probe in an ultrasonic diagnostic apparatus for acquiring a 3-dimensional ultrasound image. A pair of guide rails is disposed near both side-ends of the transducer and is disposed apart therefrom by predetermined gaps. Slots are formed lengthwise at side surfaces of the guide rails. Each slot has a bottom wall and a side wall. Bearings coupled to the both side-ends of the transducer are received in the slots and roll on the bottom walls of the slots. First magnets are fixed to the both side-ends of the transducer and second magnets are fixed to the side walls of the slots along the overall length of the slots. The first magnets are received in the slots and are disposed opposite to the second magnets so that repulsive forces are generated therebetween.

Abstract: An ultrasonic transmission/reception apparatus which can image both a minute tissue around a bone part in an object and a minute tissue inside the bone, at a high resolution. The apparatus includes a system control unit which controls the synthesizers so that a first ultrasonic wave may be transmitted from one of the transmission elements while its frequency is being swept, and that a second ultrasonic wave may be transmitted from the other transmission element while its frequency is being swept with a predetermined difference frequency held relative to the frequency of the first ultrasonic wave, a signal processing unit which subjects the detection signal of the ultrasonic echo to predetermined signal processing, a signal processing unit which subjects the detection signal of the vibro-acoustic sound to predetermined signal processing, and a display-image arithmetic unit which generates B-mode image data based on the detection signals subjected to the signal processing.

Abstract: Parametric ultrasonic measurements which characterize the structure of tissue, using information from an ultrasonic signal beyond amplitude information, are obtained by combining multiple ultrasonic signals acquired at different angles, thereby reducing the variance of the calculations. Such angular compounding may be applied to detecting scatterer size, spacing, density, and attenuation.

Abstract: A method and apparatus is provided to analyze a dual wall structure having at least one hollow core therein and having the same unknown material sound velocities in walls and in post as well. A transducer is located in at least two different positions with respect to the structure, whereby the transducer propagates an ultrasonic wave toward the dual wall structure. A portion of the ultrasonic wave is reflected back to the transducer. One wave traverses a portion of the dual wall structure that has a core filled with a medium having a known material acoustic property. A second wave traverses a portion of the post that has an unknown material sound velocity. From time of flight measurements of the above mentioned waves, the wall thickness and core shift, if any, can be determined.

Abstract: A method for inspection of tubular goods includes using ultrasonic detection means to obtain wall thickness measurement of discrete sections of a tubular good and recording each measurement in association with both the longitudinal and circumferential position at which each measurement was obtained. Accordingly each measurement of wall thickness represents a small portion of the wall thickness of said tubular in three dimensional space. A plurality of said measurements may thereby be displayed by computer means in virtual three dimensional formal. Differing wall thickness readings made he represented by different shading or color display, so that anomalies of interest may be readily detected. Alternatively the recorded information may be readily processed by computer means to calculate the effect of stressors on the wall of said tubular good.

Abstract: An improved ultrasound probe includes a support member, a signal cable having a plurality of electrically conductive members and an ultrasound transducer array. Distal end portions of each of the conductive members may be separately embodied within and extend through the support member to a first side thereof. In turn, the ultrasound transducer array may be supportably mounted to the first side of the support member, wherein transducer elements comprising the ultrasound transducer array are electrically interconnected to different ones of the electrically conductive members. The support member preferably includes an acoustic dampening material. In one embodiment, the ultrasound transducer array may be defined by a piezoelectric layer having electrically conductive signal and ground layers on opposing sides thereof.

Abstract: An ultrasonic testing assembly structured to examine a test object, wherein the test object has a surface, and the examination examines the structure of the test object under the surface as well as the profile of the surface.

Abstract: The invention relates to a device that is used to analyse the structure of a material. The inventive device comprises: probe elements (5) which are used to (i) emit a wave, in the material, with emission delay laws that correspond to several simultaneous deviations and (ii) receive, on the different probe elements (5), signals from the refraction of said wave by the material; detection channels, each detection channel being connected to a probe element (5), in order to collect the refraction signals and to transmit same to data processing means (4); and delay circuits that apply a delay on each detection channel according to the reception delay laws which are predetermined and which correspond to the different deviations of the wave emitted. The invention also relates to an analysis method which can be used, in particular, on said device.

Abstract: A method is disclosed for nondestructively examining airfoils for defects without removing them from the turbine machines of which they are a part. The method uses phased array ultrasound technology, which can be used with all types of airfoils. The angle of entry of the ultrasonic beam is varied by using phased array ultrasound technology. The phased array ultrasound allows an inspector to steer the ultrasonic beam toward an area of interest within the airfoil. The phased array allows an inspector to monitor multiple angles at once. So long as the scan angle does not exceed a calibrated range, an inspector can monitor an area of interest, no matter what the sound beam entry surface angle is. The ultrasonic beam is steered or phased to inspect different orientations with one scan. The method uses a phased array transducer that is a linear array probe that is comprised of a series of transducers.

Abstract: An ultrasound system determines the presence of a foreign object in a container of fluid by measuring echo signals from the outer surface of the container and the inner surface of the container. The amplitude of the echo signals are compared to determine the presence of an object in the container. The system also determines viscosity of the contained fluid by measuring a through-transmission time through the container and the fluid, measuring an outer echo transmission time of an outer echo signal from the outer surface of the container and an inner echo transmission time of an inner echo signal from the inner surface of the container, and determining a time difference between the outer echo transmission time and the inner surface transmission time.

Abstract: An apparatus for the internal inspection of pipes and tubes or the like, comprising an ultrasonic measuring head and a cable coupled to the measuring head, which cable can be coupled outside the pipe or tube to be measured to a device processing the measuring data, the apparatus being provided at its distal end but behind the measuring head, with a reel for winding the cable on and off.

Abstract: An ultrasonic inspection instrument for detecting a crack and performing sizing in the depth direction of the crack. By a transmitter element array and a receiver element array included in a common sensor, focus points between focused acoustic fields are electronically scanned in a range including a location where half the sum of the transmitting angle of ultrasonic waves to an inspection-target material and the receiving angle of diffraction echoes from the inspection-target material is 30 degrees, so that a tip portion of the crack is detected from the received diffraction echoes. Thus, the detectability of the ultrasonic inspection instrument for detecting diffraction waves in a subject to be inspected and performing crack inspection is stabilized and kept high.

Abstract: An ultrasonic imaging apparatus and method combines dynamically focused reception and coded transmission/reception technologies by inexpensive circuitry. A receive aperture is divided into smaller apertures. Correspondingly, a receive beam former is divided into receive sub-beam formers 36a to 36n by which a phase alignment and summing process is performed. Thereafter, coded signals are compressed in decoders 37a to 37n in a time axis direction. Output signals from the decoders are once again subjected to a phase alignment and summing process in a second beam former.

Abstract: The invention concerns a method and a device for inspecting pipelines, in particular for detecting defects in pipelines by means of ultrasound. Towards this end, measuring sensors transmit ultrasound signals during passage through a pipeline. The signals reflected on boundary regions of a pipeline wall, e.g. surfaces or defects, are then measured and evaluated. The invention is characterized in that partial regions of the measuring sensors (virtual sensors) formed of a plurality of neighboring sensor elements irradiate ultrasound signals into the pipe wall at at least one radiation angle which is inclined with respect to the normal to the pipe wall and the signals reflected at boundary regions of the pipe wall are received by same and/or other partial regions of the respective measuring sensors, wherein defects in the pipe wall are determined by evaluation of the acoustical signals reflected by different boundary regions.

Abstract: An ultrasonic inspection method includes exciting a first set of transducers in an array to introduce ultrasonic energy into a component, generating a number of echo signals using a second set of transducers in the array as receive elements, and processing the echo signals. The first and second sets of transducers are exclusive of one another, and the first and second sets of transducers are interleaved.

Abstract: A method for inspecting a component includes exciting a number of transducers forming an array to produce an ultrasonic transmission beam (beam) focused into the component. The array and the component are separated by a standoff. A number of echo signals are generated using the transducers, and the echo signals are processed in a number of channels. The processing includes both dynamical focus and providing a dynamic aperture on receive, both of which compensate for refraction of the beam at the component/standoff interface. A single-turn inspection method includes: (a) positioning the array facing the component, (b) exciting the transducers, (c) generating a number of echo signals, (d) changing the relative angular orientation of the array and the component around an axis and repeating steps (b) and (c), and (e) processing the echo signals to form at least one processed echo signal.

Abstract: The invention relates to a device for inspecting hollow spaces such as pipes, conduits, structures or containers. The device consists of the following: a probe with a built-in camera (5.0) whose objective is oriented towards a front end of a base body (1.0) of said probe; a hose-type supply line to the probe for a liquid or gaseous medium, said line being connected to the back end of the base body of said probe; a supply unit for the hose-type supply line, which is situated outside of the area where the probe is being used; at least one outlet nozzle (3.0) for the medium, which is located on the probe; and transmission means which are provided between the camera (5.0) and an evaluating and/or reproducing unit. At least three rotating outlet nozzles for the medium are situated on the periphery of the base body (1.0) between its front and back end and the jet axis of the medium is angled at 0° to 45° from the central longitudinal axis between the front and back end of the base body (1.0).

Abstract: An ultrasound imaging system and method for making a harmonic image of a good SNR (signal-to-noise ratio) by effectively removing fundamental frequency components through a pulse-compressing using weighted chirp signals, is provided. The ultrasound imaging system includes: a transducer array for converting weighted chirp signals to ultrasound signals, and transmitting the ultrasound signals to a target object; a receiver for receiving signals reflected from the target object; a pulse-compressor for selectively pulse-compressing fundamental frequency components or harmonic frequency components in the reflected signals; and a producer for producing receive-focused signals from the pulse-compressed signals. Therefore, the ultrasound imaging system can form ultrasound image using the fundamental frequency components, and can form ultrasound harmonic image using the harmonic frequency components according to 2fo-correlation method or 2fo-correlation (PI) method.

Abstract: An ultrasound system determines the presence of a foreign object in a container of fluid by measuring echo signals from the outer surface of the container and the inner surface of the container. The amplitude of the echo signals are compared to determine the presence of an object in the container. The system also determines viscosity of the contained fluid by measuring a through-transmission time through the container and the fluid, measuring an outer echo transmission time of an outer echo signal from the outer surface of the container and an inner echo transmission time of an inner echo signal from the inner surface of the container, and determining a time difference between the outer echo transmission time and the inner surface transmission time.

Abstract: An ultrasonic inspection instrument for detecting a crack and performing sizing in the depth direction of the crack. By a transmitter element array and a receiver element array included in a common sensor, focus points between focused acoustic fields are electronically scanned in a range including a location where half the sum of the transmitting angle of ultrasonic waves to an inspection-target material and the receiving angle of diffraction echoes from the inspection-target material is 30 degrees, so that a tip portion of the crack is detected from the received diffraction echoes. Thus, the detectability of the ultrasonic inspection instrument for detecting diffraction waves in a subject to be inspected and performing crack inspection is stabilized and kept high.

Abstract: There is described apparatus for inspecting a non axi-symmetric elongate body comprising: at least one exciter array having a plurality of wave exciters operable to couple to an exterior surface of said elongate body; a driver unit operable to generate driving signals to excite said plurality of wave exciters wherein each driving signal to a respective wave exciter of said array is weighted with respect to driving signals to other wave exciters in said array such that a guided acoustic wave mode is excited; a receiving unit having a plurality of wave exciters in said array such that a guided acoustic wave mode is excited; a receiving unit having a plurality of wave receivers capable of receiving reflected guided acoustic waves; an analysis unit operable to analyse received waves to assess a condition of said non axi-symmetric elongate body.

Abstract: A tuned wave phased array includes a plurality of spaced transmitter elements, a signal generator that produces an activation signal for activating the transmitter elements to transmit a guided wave in an associated medium and a delay circuit for sequentially delaying the activation of at least one of the transmitter elements for creating constructive interference of a selected mode of the wave propagating in the medium, thereby boosting the selected mode of the wave.

Abstract: Ultrasonic multi-element transducers and methods for achieving higher throughput rates in non-destructive testing are provided. By driving the transducer elements sequentially and/or in different combinations, and multiplexing the signals received from each transducer element, the inspection speed at high test sensitivity levels is significantly increased while the number of channels is not increased and cross-talk between the different transducer elements is avoided. At least one such transducer may be mounted on a rotary tester for testing manufactured objects such as tubes and bars.

Abstract: A system and method for individually varying the orientation of scan lines in at least two dimensions in an ultrasound scan are disclosed. In one embodiment, the invention includes a system for generating a three-dimensional ultrasound volume scan, comprising a transducer probe having elements arranged in a plurality of dimensions and a system controller capable of generating a scan line apparently emanating from a location other than the geographic center of the transducer probe.

Abstract: The present invention provides a method, system, and an apparatus for detecting anomalies in a wooden member. The apparatus includes a first roller device comprising a first array of transducers, and a second roller device comprising a second array of transducers. A first transducer in the first array of transducers communicates with more than one transducer in the second array of transducers. The apparatus may be designed such that the wooden member may pass between the first roller device and the second roller device. In addition, the first array of transducers and the second array of transducers maintain an orientation perpendicular to the moving direction of the wooden member as the first roller device and the second roller device roll along the wooden member. Each of the transducers operate in an ultrasonic frequency range. Also, each transducer in the first array of transducers is acoustically isolated from each other transducer.

Abstract: An ultrasonic scanner for inspection of radiused regions having scanner supports which include pivoted fingers containing the transducers and hands supporting the fingers attached to vertical arms by pins. The angle of the hands are controlled by the vertical position of the arms.

Abstract: A process for setting a focus in a ultrasonic imaging system includes receiving a point of interest and range of interest by a user input. A system controller of the system sets a focus zone on the point of interest and adjusts the aperture and apodization for the range of interest. If the range of interest can not be covered by one focal zone, further focal zones are added.

Abstract: Ultrasonic multi-element transducers and methods for achieving higher throughput rates in non-destructive testing are provided. By driving the transducer elements sequentially and/or in different combinations, and multiplexing the signals received from each transducer element, the inspection speed at high test sensitivity levels is significantly increased while the number of channels is not increased and cross-talk between the different transducer elements is avoided. At least one such transducer may be mounted on a rotary tester for testing manufactured objects such as tubes and bars.

Abstract: The invention relates to a method and a device for determining the thickness and topography of buoyant objects, especially ship's hulls (1), by means of a beam (2, 17) carrying an array of ultrasound sensors (3). The object (1) and the beam (2) are moved relative to each other in the object's longitudinal direction while the distance between the object and the beam are automatically adjusted by raising/lowering the beam (2) by means of lifting means (6) and/or distance elements secured by floating bodies (4). The invention also relates to a device for implementing the method.

Abstract: An ultrasonic sparse imaging array includes a substrate of an acoustically absorptive material, through which extend a multiplicity of holes. Adhesive sheets, having selectively conductive regions, are fixed to a first side of the substrate, and are each disposed over a first end of one of the holes. Plano-convex shaped transducer elements, having a wide acoustic field of view, are disposed on each of the sheets, each of the sheets serving as a positive electrode and providing a mechanical and electrical connection between the substrate and a multiplicity of transducer elements. Plating is fixed to the first side of the substrate and covers each of the transducer elements and comprises a negative electrode. A conductive epoxy fills each of the holes and a power source is in electrical communication with the negative electrode.

Abstract: Apparatus and method for indicating mechanical stiffness properties of body tissue employing Doppler imaging techniques. Ultrasonic signals that are transmitted to the target not only are reflected for developing images of the target from the reflections, but, by appropriate selection of the intensity of the transmitted signals, the body tissue being investigated is deformed or moved when the transmitted signals impinge on the target. The deformation or movement of the body tissue being investigated is imaged and is representative of the mechanical stiffness of this body tissue.

Abstract: Ultrasound images are obtained using a set of Golay codes with orthogonal property as ultrasound receiving and transmitting signals. Ultrasound signals having a plurality of codes are transmitted simultaneously by using the orthogonal property of the Golay codes. A superior signal-to-noise rate (SNR) is realized using the Golay codes, without suffering a decrease in the frame rate.

Abstract: A method for inspecting an irradiated fuel element in a nuclear power plant includes the step of measuring, with a measuring device, a spacer of a fuel element for providing measurements of the spacer. The measuring device also measures a calibration rod for providing measurements of the calibration rod, the calibration rod having known dimensions. The measurements of the spacer are calibrated by using the measurements of the calibration rod. It is possible thereby to measure at least the maximum width of the spacer with a measuring error of less than 20 &mgr;m. A device for inspecting an irradiated fuel element in a nuclear power plant is also provided.

Abstract: The present invention provides an ultrasonic probe and method for making the same is provided which has an advantageous construction and method of assembly. The ultrasonic probe has a segmented ultrasonic transducer having a plurality of individual independent transducers, a plurality of piezoelectric transducers connected to a first end of a respective individual independent transducer; and a plurality of electrical connections electrically communicating each the piezoelectric transducer with a power source.

Abstract: A method for acoustic imaging by angle beam, which includes generating a sound wave, coupling the wave at an angle to a first surface of a test piece via a physically continuous path. The test piece also has a second surface. The angle being such that the wave progresses along a vectors at an angle to the first surface and the second surface and along the test piece via a plurality of sound reflections reflecting between the first surface and the second surface at points progressing away from the transducer location. The angle also being such that the sound reflections at the first surface produce energy at the first surface such that a first part of every reflection of the wave continues through the first surface in the form of wave through a media toward a CCD acoustic imaging camera, while a second part of the reflection continues along in the test piece.

Abstract: An inspection apparatus for inspecting welds in a nuclear reactor jet pump includes a probe subassembly rotatably and linearly movably coupled to a frame structure configured to attach to a top flange of the reactor pressure vessel. The probe subassembly includes a plurality of probe arms pivotably coupled to a housing, with each probe arm including a sensor. The probe arms are pivotably movable between a first position where the probe arms are parallel to a longitudinal axis of the probe subassembly, and a second position where the probe arms are at an angle to the longitudinal axis of the probe subassembly. An insertion subassembly couples to the jet pump suction inlet. The insertion subassembly is sized to receive the probe subassembly and guide the probe subassembly into the jet pump through the jet pump suction inlet.

Abstract: An ultrasonic diagnostic imaging system receives echo signals from a transducer for digital processing and image formation. An analog to digital converter converts the analog echo signals to digital signal samples. The dynamic range of the analog to digital converter is more efficiently used for harmonic imaging and saturation of the analog to digital converter is more effectively prevented by attenuating the fundamental signal content of echo signals prior to analog to digital conversion.

Abstract: In a thickness reducing management for pipes in pipe lines, limited proper parameters which cause erosion and corrosion of the pipes are selected and with these parameters a pipe thickness reducing speed evaluation model formulas are constructed, and by making use of the model formulas thickness reducing amount of the pipes is evaluated. Thereby, conventional difficulty of formulating a proper pipe thickness reducing estimation model formula in view of actual pipe material and pipe inner fluid state because of too many possibly influential parameters causing pipe thickness reducing due to erosion and corrosion, and conventional difficulty of performing highly reliable pipe thickness reducing management are overcome.

Abstract: A method for the concurrent ultrasonic inspection of partially completed welds is disclosed and which includes providing a pair of transducers which are individually positioned on the opposite sides of a partially completed weld to be inspected; moving the transducers along the length of and laterally inwardly and outwardly relative to the partially completed weld; pulsing the respective transducers to produce an ultrasonic signal which passes through or is reflected from the partially completed weld; receiving from the respective transducers ultrasonic signals which pass through or are reflected from the partially completed welds; and analyzing the ultrasonic signal which has passed through or is reflected from the partially completed weld to determine the presence of any weld defects.

Abstract: An apparatus as disclosed for mounting a liquid-filled pipe by the use of ultrasound techniques. The apparatus comprises a vehicle capable of fitting inside the pipe, and of being transported along the pipe by the liquid flowing into it, together with rings of several ultrasonic transducers spaced circumferentially round the vehicle. The rings are so arranged that one ring operates in the reflection mode purely radially while two further rings operate as a pair in a longitudinal refraction mode. A fourth ring is used in a circumferential refraction/reflection mode. The vehicle has an associated power supply, data gathering and storage capability and a vehicle for measuring the distance traveled along the pipe.

Abstract: An acoustoelectronic method and apparatus for generating real-time three-dimensional images of an object and characterizing such object are provided. The object is insonified with an incident acoustic signal derived from an electrical signal. Acoustic signals scattered from the object are collected by an acoustic receiver, which generates analog electrical signals that are subsequently converted to digital electronic signals. The digital electronic signals are used in both direct-imaging and holographic methods to produce a three-dimensional representation of the object from which images and characterizations can be generated.

Abstract: A system and method for reducing parallel beamforming artifacts. An interpolation of amplitude data is performed to correct for the blocky appearance of images formed with parallel receive beams. In addition, the transmit beam is modified to approximate a rectangular beam.

Abstract: A method and an apparatus for correcting refraction delay errors on curved probes for all ranges using cordic rotation. The angle &phgr; from the normal of an element to the focus is determined as a function of the angle of cordic rotation. Then a delay error correction is indexed using this angle &phgr;. The angular correction method is efficient in that it uses the inherent property of cordic rotation to calculate the only range-dependent variable required for the correction. Thus the additional hardware required to calculate the corrections is minimal, as the remaining correction variables are vector and range independent.

Abstract: An aircraft has several ultrasonic phased arrays acoustically bonded to parts of its structure to be monitored. The arrays are energized to produce an ultrasonic beam that scans the structure in two planes. A monitor receives the output from the arrays produced by reflection of energy from discontinuities within the structure. When there is a change in these outputs, the monitor signals a pilot display unit and a flight control system such that the aircraft flight envelope can be restricted to minimize damage.

Abstract: In dual line ultrasound beamforming, an ideal transmit beam should have two peak locations, each following one of the receive beams. Dual beam steering by apodization creates such transmit beam; however, the resulting beam is optimized for only a single depth and significant line warping can occur away from that depth. The transmit beam shape in ultrasound multiline acquisition however, is improved by numerically optimizing the transmit beam, i.e., the aperture function, such that no line warping occurs over the entire depth of field. The aperture function is numerically optimized by numerically optimizing a Cost function which is dependent on the aperture function. The numerically optimized aperture function is then used in a multiline acquisition mode of an ultrasound imaging system.

Abstract: A method for realizing a transmit focusing in an ultrasonic imaging system is provided, which is a method for realizing a transmit focusing with respect to all imaging points by synthesizing pulse patterned plane waves having the same imaging point using transmit data and receive data with respect to plane waves of each pulse pattern having a different travelling direction and a linear time delay.