EP0210358B1 - Akustische Fokussierungsanordnung - Google Patents

Akustische Fokussierungsanordnung Download PDF

Info

Publication number
EP0210358B1
EP0210358B1 EP86106659A EP86106659A EP0210358B1 EP 0210358 B1 EP0210358 B1 EP 0210358B1 EP 86106659 A EP86106659 A EP 86106659A EP 86106659 A EP86106659 A EP 86106659A EP 0210358 B1 EP0210358 B1 EP 0210358B1
Authority
EP
European Patent Office
Prior art keywords
sound
lens arrangement
acoustic lens
arrangement according
transducer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP86106659A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0210358A3 (en
EP0210358A2 (de
Inventor
Abdulla Dr. Atalar
Hayrettin Dr. Köymen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Leica Microsystems Holdings GmbH
Original Assignee
Leica Industrieverwaltung GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Leica Industrieverwaltung GmbH filed Critical Leica Industrieverwaltung GmbH
Priority to AT86106659T priority Critical patent/ATE77708T1/de
Publication of EP0210358A2 publication Critical patent/EP0210358A2/de
Publication of EP0210358A3 publication Critical patent/EP0210358A3/de
Application granted granted Critical
Publication of EP0210358B1 publication Critical patent/EP0210358B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/26—Sound-focusing or directing, e.g. scanning
    • G10K11/28—Sound-focusing or directing, e.g. scanning using reflection, e.g. parabolic reflectors
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/36—Devices for manipulating acoustic surface waves
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K15/00—Acoustics not otherwise provided for

Definitions

  • the invention relates to an acoustic lens arrangement according to the preamble of claim 1.
  • a lens arrangement of this type is e.g. known from US-A-4 028 933.
  • a piezoelectric transducer is arranged on one side of a cylindrical sapphire rod and a spherical hollow surface is incorporated on the opposite side.
  • An electrical high-frequency field applied to the transducer generates a flat acoustic wave field in the sapphire rod, which is focused by the spherical hollow surface in an adjacent immersion liquid.
  • the lens arrangement is part of an acoustic microscope.
  • An object to be examined is brought into the acoustic focus.
  • acoustic waves emanate from it, which are collected by the same or another acoustic lens and im piezoelectric transducers can be converted into electrical signals.
  • the acoustic waves that are regularly reflected or transmitted on the object are used for acoustic microscopy.
  • acoustic waves that hit a surface of the object at a certain material-dependent angle (Rayleigh angle ⁇ R ) excite surface waves in this surface (surface acoustic waves, SAW).
  • SAW surface acoustic waves
  • the SAW scatter acoustic waves out of the object (leaky waves, leak waves).
  • These waves can also be detected and converted into electrical signals.
  • they are superimposed on the regular signal, especially when focusing on an object area lying below the object surface. They can also be evaluated separately using special circuit measures (cf. DE Pat. Application P 34 09 929.8).
  • the SAW When the SAW encounters inhomogeneities in the object surface, the SAW are reflected on it, so that they change their direction of propagation. The result of this is that leakage waves also occur increasingly in this direction. Since the SAW penetrate relatively deeply into the object surface, they are now increasingly becoming one used to determine material properties of different objects.
  • the particular advantage is that it is a non-destructive measurement method that also allows quantitative measurements. To do this, however, it is necessary to increase the local resolving power and to improve the signal yield.
  • the first problem is to generate the SAW as efficiently as possible in the surface of the material to be examined, which is generally not piezoelectric.
  • the second problem is to focus the generated SAW on the smallest possible spot size.
  • the invention was therefore based on the object of specifying an acoustic lens arrangement which, with the highest possible conversion rate of the radiated sound wave field into SAW, enables a point-like focusing of the SAW which is simple to manufacture and ensures a high signal yield.
  • V I is the rate of propagation in this medium. If it is a solid transmission medium, V I can be the propagation speed of the longitudinal waves or the shear waves in the solid, but it can also be the propagation speed in a gaseous medium.
  • the incident acoustic beam is to be represented by a plane wave of the form exp [j (k y ⁇ y + k z ⁇ z)].
  • exp j (k y ⁇ y + k z ⁇ z)].
  • a parabolic cylindrical mirror focuses a vertically striking plane wave in a line
  • an obliquely striking plane wave is focused in a line with a linearly variable phase.
  • the wave fronts are conical and in the present case the axis of the cone coincides with the focal line of the parabolic cylinder.
  • an ultrasound beam excites the more intensely the angle of incidence coincides with the Rayleigh angle as it passes through a liquid / solid interface in the surface of the solid SAW.
  • this fact is combined with the special properties of the reflector described, in that the angle of incidence of the beam generated by the acoustic transducer on the reflector is selected to be equal to the Rayleigh angle.
  • the wavefront running towards the interface with the object then cuts the object surface in an arc with a decreasing radius.
  • Each surface wave generated will amplify the surface wave generated in front of it with a larger radius, since the selected special angle of incidence of the acoustic wavefront matches the k-vector component of the surface wave along the transition interface.
  • the generated SAW have a limited lifespan and are ultimately scattered back into the liquid layer as longitudinal waves. These waves, also known as leakage waves, can arise as soon as the surface waves are generated. If the surface of the object is perfectly flat and has no impurities, ie there are no surface wave reflectors, almost no leakage waves will return to the transducer. Since the incident beam is limited in diameter and plane waves are also contained in its angular spectrum, SAW can also be excited towards the reflector, ie it runs backwards. The leakage waves resulting from these SAWs will then generate an output signal at the acoustic transducer, even if there are no impurities in the surface. However, this effect is very low and can be further suppressed by appropriate beam expansion and suitable shaping of the reflector.
  • the acoustic transducer only receives a sufficiently strong signal if the direction of propagation the forward running SAW is changed at any point of failure.
  • the SAW is reflected on it and runs back as a circularly divergent wave.
  • the waves scattered back into the liquid reassemble in the original conical wavefront and are returned to the acoustic transducer by the reflector as a collimated beam. If the point of impurity is not exactly in the focus point, the wavefront reflected on it will not be able to exactly restore the originally radiated beam, so that the output signal of the converter is smaller than in the in-focus position.
  • An exemplary embodiment is shown schematically in FIG. 1.
  • the acoustic lens arrangement consists of an acoustic transducer 1, a cylindrical mirror 2 and a mechanical connection 3, with which the angle of inclination and the position of the transducer 1 can be adjusted relative to the mirror 2 so that the transducer sonicates the entire mirror surface regardless of the angle of inclination.
  • the arrangement is immersed in a water bath 4 serving as immersion during operation.
  • the mirror 2 is arranged on the object 5 to be examined so that the longitudinal axis 6 of its cylindrical hollow surface 7 is perpendicular to the object surface.
  • the pulsed sound wave field 8 generated by the transducer 1 falls on the mirror 2 at the Rayleigh angle ⁇ R.
  • the plane phase front produces a conically shaped phase front 9, which also strikes the object surface at the Rayleigh angle ⁇ R and excites SAW 10 in it.
  • the rays reflected from the object surface are picked up by the transducer 1 and converted into corresponding electrical signals which are displayed on an oscilloscope (not shown).
  • a micropositioning system also not shown, allows a raster-shaped relative displacement between acoustic lens arrangement 1, 2, 3 and object 5 to be examined.
  • the converter 1 consists of a flat ceramic disk, the thickness of which is designed for a resonance frequency of 1 MHz.
  • the transition surface to the immersion liquid 4 is provided with a ⁇ / 4 adaptation layer, not shown.
  • the transducer is driven by a voltage pulse lasting approximately 0.2 microseconds, which generates a sinusoidally falling pressure pulse.
  • the emitted ultrasound pulse is about 5 microseconds long and has a center frequency of 1 MHz.
  • the cylindrical hollow surface 7 should have a parabolic shape. Since this is difficult to manufacture, experiments with a circular cylindrical mirror surface have been successfully carried out as an approximation to this shape.
  • the geometric limitation of this simplified hollow surface was chosen so that when the reflector is sonicated with a flat wavefront, the marginal rays form the central ray have a path difference of not more than ⁇ / 4, where ⁇ is the wavelength of the ultrasound beam in the immersion liquid 4.
  • a certain focal length must be selected, which depends on the frequency of the ultrasonic wave field used and the material to be examined.
  • the optimal focal length f opt can be read from FIG. 2.
  • f opt is normalized with respect to the Schoch shift ⁇ s and plotted as a function of ⁇ s / ⁇ , where ⁇ is the sound wavelength in the immersion liquid.
  • ⁇ is the sound wavelength in the immersion liquid.
  • the ratio ⁇ s / ⁇ is given by where V is the speed of sound in the immersion liquid and V s , V1 and V R are the shear, the longitudinal and the Rayleigh sound speeds in the solid to be examined.
  • f opt is equal to half the radius.
  • An f opt of 12.5 mm can be realized with a cylinder of 50 mm diameter and an f opt of 1.05 mm with a cylinder of 4.2 mm diameter.
  • the maximum width 2x m of the reflector with no significant cylindrical aberrations can be calculated using the following formula:
  • the lens arrangement achieves a maximum resolution. It is 22.4 mm for aluminum at 1.5 MHz ultrasonic frequency and 1.22 mm for Al2O3 at 100 MHz.
  • the aperture (f number) of the lens arrangement can be determined as follows using the values already determined will: and gives 0.56 for aluminum and 0.86 for Al2O3.
  • the height H of the reflector should be equal to f opt ⁇ cot ⁇ R when the base of the reflector almost touches the object surface to be examined.
  • the optimal height is 21.7 for aluminum at 1.5 MHz and 4 mm for Al2O3 at 100 MHz.
  • Suitable as mirror material e.g. Brass, which has a high acoustic impedance compared to the immersion liquid water.
  • the mirror had a height of 38 mm, a width of 37 mm and a cylinder radius of 50 mm. These dimensions deviate slightly from the theoretical limits for the investigation of aluminum. However, it has been shown that the losses in signal power due to this are negligible.
  • an ultrasonic frequency of 1 MHz results in a wavelength of the SAW of 2.85 mm, which also means the diameter of the diffraction-limited focus and the layer thickness of the object surface in which the SAW run. Inhomogeneities lying within this layer thickness can be recognized on the basis of the sound waves reflected back at them.
  • a 10 mm thick test plate therefore looks like an almost infinitely thick object for the SAW.
  • the acoustic lens arrangement should initially be arranged in the middle of a sufficiently large test area. This case is shown schematically in FIG. 3.
  • the oscilloscope image of the measurement signal shown in FIG. 3a shows only one echo pulse 20.
  • This signal is due to the fact already described that the acoustic wave front generated by the acoustic transducer is not exactly flat and that beam components also hit the reflector 2 whose angles of incidence deviate more or less from the Rayleigh angle ⁇ R. These are reflected at the edge between the object surface and the cylindrical hollow surface and generate the echo signal.
  • This signal can be minimized by optimizing the transducer and reflector geometry and setting a suitable detection sensitivity. If the acoustic lens arrangement, as shown in FIG. 4, is shifted to the edge of the test surface such that the focus of the SAW lies exactly on the edge, then a second significantly larger echo pulse 21 is observed in the oscillogram. This is shown in FIG. 4a and enlarged again in FIG. 4b.
  • the distance between the two echo pulses 20, 21 is 17 microseconds. This corresponds to the running time of the SAW for a distance of 50 mm, ie twice the focal length. From this, a very simple method for the exact setting of the Rayleigh angle ⁇ R between the beam direction of the plane sound wave field emanating from the transducer and the longitudinal axis of the reflector can be derived.
  • the reflector is to be arranged at a distance of its focal length from an edge of the object to be examined and the angle of inclination of the transducer is to be changed until the amplitude of the echo pulse 21 has a maximum.
  • the device for adjusting the angle of inclination between the transducer and reflector is used primarily to optimize the object-dependent Rayleigh angle ⁇ R for the almost lossless conversion of the radiated sound wave field into SAW.
  • other waves in the object can also be excited, which also depend on the angle of incidence of the ultrasound beams depend on the liquid / object interface.
  • Such waves are known for example under the designation love waves, Stonely waves and Sezewa waves. If, for example, the object to be examined has several layers of different materials lying on top of one another, these waves can be selectively excited if the angle of incidence in the liquid is set appropriately.
  • the waves entering the object are focused in a similar way to the SAW. This makes it possible to achieve a greater depth of penetration for the acoustic focus than with the SAW.
  • the device according to the invention has been described above for applications with relatively low ultrasound frequencies. However, it can also be used in acoustic microscopes that use ultrasound frequencies up to the GHz range.
  • a suitable lens arrangement is shown in FIG. 5.
  • a rod 40 made of a material with low acoustic losses, such as sapphire, is provided with parallel, flat polished end faces.
  • An acoustic transducer 41 (ZnO) is located on one side and lies between two gold electrodes 42, 43. The other side is provided with a ⁇ / 4 antireflection coating made of glass or carbon with a suitable acoustic impedance in order to achieve a good adaptation for the transition of the ultrasound rays into the immersion liquid, not shown.
  • the cylindrical, preferably parabolically shaped reflector 44 is glued to this side of the rod 40 so that a certain one Rayleigh angle ⁇ R to its longitudinal axis is created.
  • It consists, for example, of aluminum or another solid material with high acoustic impedance.
  • the geometric dimensions (height and width) and the focal length must be adapted to the intended ultrasound frequency. They decrease almost linearly in proportion to the quantities mentioned for 1 MHz with the increase in the ultrasound frequency. For this reason, it will be expedient to provide different fixed lens arrangements with a reflector inclined in accordance with the required Rayleigh angle ⁇ R for the examination of different materials. In principle, however, the angle of inclination can also be made adjustable here, which allows an individual adaptation to the examination object.
  • the transducer 1 and the cylindrical surface 7 that is hollow relative to the transducer are formed on the outer surfaces of a solid body 60 suitable for sound transmission.
  • a metal layer is evaporated onto the cylinder surface 7.
  • An immersion liquid can also be inserted between the exit surface of the lens arrangement and the object surface for better coupling of the focused sound beam to the object surface.
  • FIG. 7 Another embodiment is shown in FIG. 7. With this arrangement, the sound focusing is now generated by refraction on such a surface instead of a reflection on the cylinder surface perpendicular to the object surface.
  • the sound transmission from the transducer 1 takes place through a solid body 70 to the cylindrical hollow surface 7, which in this case is curved towards the transducer and whose longitudinal axis 6 is perpendicular to the object surface 5.
  • the normal direction on the flat sound wave field emanating from the transducer is inclined at an angle ⁇ i with respect to the object surface.
  • the space between the hollow surface 7 and the object surface 5 is filled with an immersion liquid, not shown.
  • the hollow surface 7 acts in the horizontal direction like a cylindrical lens.
  • Snell's law of refraction must be observed in the vertical direction: V solid state and V immersion denote the phase velocities of the sound waves in the two transmission media. After the refraction, a conical wavefront is created as in the previous ones described reflection lens assemblies.
  • the inclination of the transducer plane is to be chosen so that the sound waves hit the object surface at the critical angle ⁇ R , taking into account the refraction at the hollow surface 7. Then SAW are generated in the object surface, which are focused at one point. It should also be mentioned that both longitudinal waves and shear waves can be excited in the sound propagation in the solid body 70. V solid then means the phase velocity for the wave type used in each case. To avoid transmission losses, the hollow surface 7 must be provided with a suitable anti-reflective coating.
  • the maximum size of the angle (90-ers R ) is determined by the choice of the solid 70 and the immersion liquid. Due to this fact, the selection of the solid transmission medium is restricted depending on the material properties of the object to be examined. The basic principle is that the sound propagation speed in the solid body 70 must be lower than in the object surface 5.
  • the acoustic transducer is usually used alternately as a transmitter and a receiver in the pulse-echo method.
  • the sound waves returning from the object are combined with the radiated ones interfere so that a phase-modulated signal is produced at the converter.
  • FIG. 8 shows an embodiment with two confocal lens arrangements, one of which serves as a transmitter and the other as a receiver for the sound waves, as indicated by the arrow directions. Both arrangements are on the same axis of SAW propagation. Such a structure can of course work with both continuous and pulsed sound wave generation. In pulse-echo mode, two signals can be obtained which are assigned to the sound wave components scattered backwards in the direction of the transmitter and to the sound wave components scattered forward in the direction of the receiver.
  • the arrangement of two confocal lens arrangements shown in FIG. 9 is selected such that the directions of the SAW propagation form an angle ⁇ with one another. This angle can be made adjustable. This arrangement is also suitable for continuous and pulsed sound generation. It can be used to determine anisotropies in the SAW reflection in particular.
  • the embodiment shown in FIG. 10 works with only one reflector and a two-part converter, one of which can be used as a transmitter and the other as a receiver in both continuous and pulsed operation.
  • the imaging properties of the reflector ensure sufficient directional selection between the transmitted and the received sound beam bundle, so that the two beams do not interfere with each other or only to a very small extent, regardless of the orientation of the dividing line between the transducers.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
  • Surgical Instruments (AREA)
  • Transducers For Ultrasonic Waves (AREA)
  • Diaphragms For Electromechanical Transducers (AREA)
  • Analysing Materials By The Use Of Radiation (AREA)
EP86106659A 1985-06-24 1986-05-14 Akustische Fokussierungsanordnung Expired - Lifetime EP0210358B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT86106659T ATE77708T1 (de) 1985-06-24 1986-05-14 Akustische fokussierungsanordnung.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19853522491 DE3522491A1 (de) 1985-06-24 1985-06-24 Akustische linsenanordnung
DE3522491 1985-06-24

Publications (3)

Publication Number Publication Date
EP0210358A2 EP0210358A2 (de) 1987-02-04
EP0210358A3 EP0210358A3 (en) 1989-03-29
EP0210358B1 true EP0210358B1 (de) 1992-06-24

Family

ID=6273994

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86106659A Expired - Lifetime EP0210358B1 (de) 1985-06-24 1986-05-14 Akustische Fokussierungsanordnung

Country Status (5)

Country Link
US (1) US4779241A (ja)
EP (1) EP0210358B1 (ja)
JP (1) JPS6255556A (ja)
AT (1) ATE77708T1 (ja)
DE (2) DE3522491A1 (ja)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006003649B4 (de) * 2006-01-26 2009-03-19 Gitis, Mihail, Prof. Dr.Dr. Verfahren und Einrichtung zur Qualitätsüberwachung von technischen Einkomponenten und Mehrkomponentenflüssigkeiten mittels Ultraschall On-Line Messungen ihrer Viskosität, Dichte, Kompressibilität und Volumenviskosität
RU2618600C1 (ru) * 2016-02-09 2017-05-04 Федеральное государственное бюджетное образовательное учреждение высшего образования "Сибирский государственный университет геосистем и технологий" (СГУГиТ) Акустическая линза

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3931048A1 (de) * 1989-09-16 1991-04-11 Leica Industrieverwaltung Konisches ultraschallwellen-ablenkelement
JP2551639Y2 (ja) * 1992-01-14 1997-10-27 ダイキン工業株式会社 空気調和装置
US6327538B1 (en) * 1998-02-17 2001-12-04 Halliburton Energy Services, Inc Method and apparatus for evaluating stoneley waves, and for determining formation parameters in response thereto
US6417602B1 (en) 1998-03-03 2002-07-09 Sensotech Ltd. Ultrasonic transducer
TW490559B (en) * 1999-07-30 2002-06-11 Hitachi Construction Machinery Ultrasonic inspection apparatus and ultrasonic detector
KR100548076B1 (ko) * 2002-04-25 2006-02-02 학교법인 포항공과대학교 기체 음향렌즈 부착형 음향집중 스피커
JP4902508B2 (ja) * 2007-12-03 2012-03-21 日本電信電話株式会社 成分濃度測定装置及び成分濃度測定装置制御方法
US8616329B1 (en) 2012-10-30 2013-12-31 The United States Of America As Represented By The Secretary Of The Air Force Air coupled acoustic aperiodic flat lens
JP7173931B2 (ja) * 2019-06-07 2022-11-16 日立Ｇｅニュークリア・エナジー株式会社 超音波検査装置
US20240111037A1 (en) * 2022-09-29 2024-04-04 Navico, Inc. Reflective surface beamforming

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2611445A (en) * 1948-01-29 1952-09-23 Stromberg Carlson Co Echo ranging system
US3159023A (en) * 1957-10-28 1964-12-01 Budd Co Ultrasonic testing apparatus
US3028752A (en) * 1959-06-02 1962-04-10 Curtiss Wright Corp Ultrasonic testing apparatus
US3389372A (en) * 1965-06-23 1968-06-18 Smiths Industries Ltd Echo-ranging apparatus
US4028933A (en) * 1974-02-15 1977-06-14 The Board Of Trustees Of Leland Stanford Junior University Acoustic microscope
US4332016A (en) * 1979-01-26 1982-05-25 A/S Tomra Systems Method, apparatus and transducer for measurement of dimensions
DE3409929A1 (de) * 1984-03-17 1985-09-26 Ernst Leitz Wetzlar Gmbh, 6330 Wetzlar Verfahren zur darstellung elastischer parameter in objektoberflaechen

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006003649B4 (de) * 2006-01-26 2009-03-19 Gitis, Mihail, Prof. Dr.Dr. Verfahren und Einrichtung zur Qualitätsüberwachung von technischen Einkomponenten und Mehrkomponentenflüssigkeiten mittels Ultraschall On-Line Messungen ihrer Viskosität, Dichte, Kompressibilität und Volumenviskosität
RU2618600C1 (ru) * 2016-02-09 2017-05-04 Федеральное государственное бюджетное образовательное учреждение высшего образования "Сибирский государственный университет геосистем и технологий" (СГУГиТ) Акустическая линза

Also Published As

Publication number Publication date
US4779241A (en) 1988-10-18
ATE77708T1 (de) 1992-07-15
DE3522491A1 (de) 1987-01-02
JPS6255556A (ja) 1987-03-11
JPH0529064B2 (ja) 1993-04-28
DE3685779D1 (de) 1992-07-30
EP0210358A3 (en) 1989-03-29
EP0210358A2 (de) 1987-02-04

Similar Documents

Publication Publication Date Title
DE2710038C2 (de) Vorrichtung zur Ultraschall-Untersuchung von Geweben eines Patienten
DE69012165T2 (de) Verfahren und Vorrichtung zum Orten und Fokussieren von Wellen.
EP0210358B1 (de) Akustische Fokussierungsanordnung
DE2915761A1 (de) Vorrichtung zur ultraschall-untersuchung eines objektes
DE3225586A1 (de) Ultraschall-mikroskop
DE2461590C2 (de) Strahlablenker, insbesondere für eine Einrichtung zur Werkstoffprüfung, sowie Anwendung des Strahlablenkers
EP0111047B1 (de) Vorrichtung zur Erzeugung von Stosswellenimpulsfolgen
DE3415283A1 (de) Akustisches mikroskop
DE3924919C2 (ja)
DE2554898C2 (de) Verfahren und Vorrichtung zur akustischen Abbildung
DE3931048C2 (ja)
DE3206111A1 (de) Wandler mit verbesserter aufloesung systeme und verfahren fuer die aussendung und/oder den empfang von durch schwingungen ausgebteiteten wellen
DE2821573C2 (ja)
EP0033463B1 (de) Ultraschall-Multi-Sensor
DE3110739A1 (de) Ultraschallabbildung mit konischen transduktor
DE102018111787B4 (de) Verfahren zur Justierung von Prüfeinrichtungen zur Ultraschallprüfung von Werkstücken
DE69204719T2 (de) Verfahren zur Auswahl von Ultraschallwandlern.
DE3221209C2 (de) Gerät zur Untersuchung von Körpern durch Abtastung mittels Ultraschall
DE3715914A1 (de) Verfahren und vorrichtung zum nachweis von rissen mit hilfe von ultraschall
DE102008005971A1 (de) Vorrichtung und Verfahren zur zerstörungsfreien Prüfung eines Prüflings mittels Ultraschall-TOFD-Technik
DE602005002534T2 (de) Bestimmung der Fläche einer lateralen Schattenzone in einem Ultraschallprüfungsverfahren
DE3200762A1 (de) Ultraschallsonde
Moshfeghi Side-lobe suppression for ultrasonic imaging arrays
DE3718972C2 (ja)
DE102013203450B4 (de) Mikroskop

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT CH DE FR GB LI NL

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT CH DE FR GB LI NL

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: WILD LEITZ GMBH

17P Request for examination filed

Effective date: 19890530

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: LEICA INDUSTRIEVERWALTUNG GMBH

17Q First examination report despatched

Effective date: 19910904

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT CH DE FR GB LI NL

REF Corresponds to:

Ref document number: 77708

Country of ref document: AT

Date of ref document: 19920715

Kind code of ref document: T

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)
REF Corresponds to:

Ref document number: 3685779

Country of ref document: DE

Date of ref document: 19920730

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19940419

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19940420

Year of fee payment: 9

Ref country code: CH

Payment date: 19940420

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19940421

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 19940426

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19940531

Year of fee payment: 9

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19950514

Ref country code: AT

Effective date: 19950514

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Effective date: 19950531

Ref country code: CH

Effective date: 19950531

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19951201

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19950514

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 19951201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19960201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19960229

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST