Ultrasound array having trapezoidal oscillator elements and a method and apparatus for the manufacture thereof

Abstract

The array (2) preferably comprises a number of adjacently located vibration elements (4) having a trapezoidal cross-section. Incisions (22) separate the individual vibration elements (4) from one another. They extend from the input coupling layer (24) via the first electrode (8), the piezoelectric material (6), the second electrode (10) into the damping body (20). The incisions (22) are preferably produced by means of an excimer laser (42), the laser light (44) of which is focused via a focusing device (46) in the form of a cylindrical lens in a line focus (54) onto the prepared layer material (40) to be cut. The layer material (40) contains piezoceramics as the piezoelectric material (6). <IMAGE>

We claim as our invention: 
     
       1. An ultrasound array comprising: a plurality of identical separated side-by-side oscillator elements each having a core of piezoelectric material and first and second spaced trapezoidal .[.electrode surfaces.]. .Iadd.electrodes .Iaddend.at opposite sides of the core coated with electrode material, said first electrode .Iadd.having a .Iaddend.surface facing an emission direction of the array and, said second electrode .Iadd.having a .Iaddend.surface being disposed at a base region of the array, said first electrode surface being smaller in area in a plane substantially normal to said emission direction than said second electrode surface, and each oscillator element further having first and second non-parallel boundary surfaces extending between .Iadd.the respective surfaces of .Iaddend.said first and second .[.electrode surfaces.]. .Iadd.electrodes .Iaddend.so that each oscillator element has a .Iadd.trapezoidal .Iaddend.cross-section which changes identically in a direction from said second electrode surface to said first electrode surface.   
     
     
       2. An ultrasound array as claimed in claim 1, wherein each oscillator element further has third and fourth boundary surfaces extending between said first and second electrode surfaces and between said first and second boundary surfaces, said third and fourth boundary surfaces being non-parallel relative to each other. 
     
     
       3. An ultrasound array as claimed in claim 2, wherein said third and fourth boundary surfaces are substantially planar. 
     
     
       4. An ultrasound array as claimed in claim 2, wherein said third and fourth boundary surfaces are trapezoidal. 
     
     
       5. An ultrasound array as claimed in claim 1, wherein said first and second boundary surfaces are substantially planar. 
     
     
       6. An ultrasound array as claimed in claim 1, further comprising a common damping member to which all of said oscillator elements are attached at said base region of the array with oscillator elements next to each other on the common damping member being separated by a V-shaped incision. 
     
     
       7. An ultrasound array as claimed in claim 1, wherein each oscillator element further has a coupling layer disposed on and covering said first electrode surface, said coupling layer having an outer surface spaced from said first electrode surface and sides extending between said outer surface and said first electrode surface, said sides of said coupling layer respectively being disposed in planes containing said first and second boundary surfaces. 
     
     
       8. An ultrasound array comprising: a carrier;   a plurality of identical side-by-side oscillator elements disposed on said carrier, each oscillator element having first and second spaced trapezoidal .[.electrode surfaces.]. .Iadd.electrodes .Iaddend.coated with electrode material, said first .Iadd.electrode having a .Iaddend.surface facing an emission direction of the oscillator elements and said second electrode .Iadd.having a .Iaddend.surface .[.being.]. adjacent said carrier, said .[.first.]. surface .Iadd.of said first electrode .Iaddend.being smaller in area in a plane substantially normal to said emission direction .Iadd.than said surface of said second electrode, .Iaddend.and each oscillator element further having first and second substantially planar, non-parallel boundary surfaces extending between .Iadd.the respective surfaces of .Iaddend.said first and second .[.electrode surfaces.]. .Iadd.electrodes .Iaddend.so that each oscillator element has a trapezoidal cross-section between said first and second boundary surfaces; and   said carrier having a plurality of parallel V-shaped incisions, each incision having spaced walls and said oscillator elements being disposed between said incisions with the walls of said incision being substantially co-planar with the respective boundary surfaces of the oscillator elements.   
     
     
       9. An ultrasound array as claimed in claim 8, wherein each oscillator element further has third and fourth non-parallel boundary surfaces extending between said first and second electrode surfaces and between said first and second boundary surfaces so that each oscillator element has a trapezoidal cross-section between said third and fourth boundary surfaces. 
     
     
       10. An ultrasound array as claimed in claim 9, wherein each oscillator element has a coupling layer disposed on and covering said first electrode surface, said coupling layer having an outer surface spaced from said first electrode surface and four sides extending between said outer surface and said first electrode surface, said four sides being respectively co-planar with said first, second, third and fourth boundary surfaces.