What is claimed is:
1. A therapeutic ultrasound delivery system, comprising:
a catheter body;
a plurality of axially spaced-apart hollow cylindrical vibrational transducers disposed along a length of the catheter body;
an outer restraint disposed around the outer surfaces of the vibrational transducers, the outer restraint exerting an inward pre-stress on the outer surfaces of the vibrational transducers; and
an inner connector disposed in contact with the inner surfaces of the vibrational transducers.
2. The system of claim 1, wherein the outer restraint is attached to the outer surface of the vibrational transducers by one of the group consisting of gluing, soldering, welding or bonding.
3. The system of claim 1, wherein the inner connector is attached to the inner surface of the vibrational transducers by one of the group consisting of gluing, soldering, welding or bonding.
4. The system of claim 1, wherein the inner and outer surfaces of the vibrational transducers are metallic.
5. The system of claim 1, wherein at least one of the outer restraint and inner connector comprises a single filament wrap.
6. The system of claim 1, wherein at least one of the outer restraint and inner connector comprises a multifilament wrap.
7. The system of claim 1, wherein the outer restraint exerts an inward pre-stress equal to about 25% to 75% of the breaking strength of the transducers.
8. The system of claim 1, wherein the outer restraint exerts an inward pre-stress at least equal to the tensile strength of the transducers.
9. The system of claim 1, wherein the outer restraint exerts an inward pre-stress that is greater than the tensile strength of the transducers, and less than the average of the compressive and tensile strengths of the transducers.
10. The system of claim 1, wherein the outer restraint exerts an inward pre-stress that is approximately equal to the average of the compressive and tensile strengths of the transducers.
11. The system of claim 1, wherein the vibrational transducers are made from the group consisting of a piezoelectric ceramic, an electrostrictive ceramic and a piezoelectric crystal.
12. The system of claim 11, wherein the vibrational transducers are made from the group consisting of PZT-8 and PZT-4 ceramic material.
13. The system of claim 1, wherein the outer restraint is a spring.
14. The system of claim 1, wherein the inner connector is a spring.
15. The system of claim 14, wherein the innerconnector pushes gently outwardly against the inner surfaces of the vibrational transducers.
16. The system of claim 13, wherein the pitch of the spring is less in regions adjacent each of the individual transducers than in regions between each of the individual transducers.
17. The system of claim 14, wherein the pitch of the spring is less in regions within the inner bores of each of the individual transducers than in regions between each of the individual transducers.
18. The system of claim 1, wherein the outer restraint is made from a material having a Young’s Modulus in the range of 10,000,000 psi to 70,000,000.
19. The system of claim 1, wherein the outer restraint is made from a material having a tensile strength in the range of 50,000 psi to 400,000.
20. The system of claim 1, wherein the outer restraint is made from a material having electrical conduction properties in the range of 9 to 100 ohms per mil:ft.
21. The system of claim 1, wherein at least one of the outer restraint or inner connector is made from a material selected from the group consisting of beryllium copper alloys, steel alloys, aluminum alloys, nickel alloys, nickel titanium alloys and tungsten alloys.
22. The system of claim 1, wherein the outer restraint is disposed around the outer surfaces of two successive vibrational transducers.
23. The system of claim 1, wherein the outer restraint is disposed around the outer surfaces of three successive vibrational transducers.
24. The system of claim 1, wherein the outer restraint is disposed around the outer surfaces of all of the transducers in the catheter body.
25. A method of assembling a system for delivering vibrational energy to a patient, comprising:
providing a catheter body;
providing a plurality of axially spaced apart hollow cylindrical vibrational transducers disposed along a length of the catheter body;
connecting together the plurality of hollow cylindrical vibrational transducers within the catheter body by:
wrapping a first spring connector around the outer surfaces of the vibrational transducers wherein the first spring connector exerts an inward pre-stress on the outer surfaces of the vibrational transducers; and
positioning a second spring connector in contact with the inner surfaces of the vibrational transducers.
26. The method of claim 25, wherein wrapping the first spring connector around the outer surfaces of the vibrational transducers comprises:
unwinding the first spring connector such that expands in diameter;
slipping the first spring connector over the outer surfaces of the vibrational transducers when the first spring connector is in an expanded state; and
allowing the first spring connector to contract around the outer surfaces of the vibrational transducers, such that the first spring connector exerts an inward pre-stress on the outer surfaces of the vibrational transducers.
27. The method of claim 25, wherein
positioning the second spring connector in contact with the inner surfaces of the vibrational transducers comprises:
winding the second spring connector such that contracts in diameter;
slipping the second spring connector through the inner surfaces of the vibrational transducers when the second spring connector is in a contracted state; and
allowing the second spring connector to expand such that it contacts the inner surfaces of the vibrational transducers.
28. The method of claim 25, further comprising:
attaching the first spring connector to the outer surfaces of the vibrational transducers by one of the group consisting of gluing, soldering, welding or bonding.
29. The method of claim 25, further comprising:
attaching the second spring connector to the inner surfaces of the vibrational transducers by one of the group consisting of gluing, soldering, welding or bonding.
30. The method of claim 25, wherein the first spring connector exerts an inward pre-stress equal to about 25% to 75% of the breaking strength of the transducers.
31. The method of claim 25, wherein the first spring connector exerts an inward pre-stress equal at least equal to the tensile strength of the transducer.
32. The method of claim 25, wherein the first spring connector exerts an inward pre-stress that is greater than the tensile strength of the transducer, and less the average of the compressive and tensile strengths of the transducer.
33. The method of claim 25, wherein the first spring connector exerts an inward pre-stress that is approximately equal to the average of the compressive and tensile strengths of the transducer.
34. A method for delivering vibrational energy to a patent, comprising:
introducing a catheter having a plurality of axially spaced apart hollow cylindrical vibrational transducers disposed therealong into a patient, wherein an outer restraint is disposed in contact with outer surfaces of the vibrational transducers and exerts an inward pre-loading on the vibrational transducers, and wherein an inner connector is disposed in contact with inner surfaces of the vibrational transducers; and
energizing the vibrational transducers to deliver vibrational energy to the patient.
35. The method of claim 34, further comprising:
cooling an inner bore in the transducer with a fluid flow.
36. The method of claim 35, wherein the fluid flow is a saline infusion.
37. The method of claim 34, wherein the vibrational transducer is operated at a Mechanical Index (MI) of at least 1.9.
38. The method of claim 34, wherein the vibrational transducer is operated at a frequency of at least 500 KHz.
39. The method of claim 34, wherein the vibrational transducer is operated at a frequency not exceeding 3 MHz.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An antenna apparatus, comprising
a waveguide formed one or more first array elements and one or more second array elements, each of the one or more first array elements being formed at a position where a coupling power ratio is no less than a threshold and including a first slot and at least one reflection suppressing element which suppresses a reflection from the first slot, each of the one or more second array elements being formed at a position where the coupling power ratio is less than the threshold and including a second slot and a third slot, the coupling power ratio indicating a ratio of an electric power supplied to each of the first and second array element to an electric power of electromagnetic wave radiated from the each of the first and second array element.
2. The apparatus according to claim 1, wherein the waveguide comprises:
a dielectric substrate including a first surface and a second surface opposing the first surface, the first surface being covered with a first conductor, the second surface being covered with a second conductor;
a first via hole array formed by arranging, at a first spacing, a plurality of first via holes which electrically connect the first conductor and the second conductor; and
a second via hole array formed by arranging, at the first spacing, a plurality of second via holes which electrically connect the first conductor and the second conductor, the second via hole array being arranged parallel to the first via hole array at a second spacing,
the one or more first array elements are formed at a position where the coupling power ratio is no less than the threshold in a region on the first surface sandwiched between the first via hole array and the second via hole array, and the one or more second array elements are formed at a position where the coupling power ratio is less than the threshold in the region.
3. The apparatus according to claim 1, wherein when setting a first threshold and a second threshold larger than the first threshold, the one or more second array elements are formed at a position where the coupling power ratio is less than the second threshold, the one or more first array elements are formed at a position where the coupling power ratio is no less than the first threshold, and at least one of the first and second array elements are formed at a position where the coupling power ratio is no less than the first threshold and less than the second threshold.
4. The apparatus according to claim 3, wherein the first threshold is five percent and the second threshold is twenty percent.
5. The apparatus according to claim 1, further comprising a power supplier configured to supply electric power to the waveguide.
6. The apparatus according to claim 5, wherein one of the second array elements is formed at a position which is close to the power supplier than a position formed one of the first array elements.
7. The apparatus according to claim 1, wherein when a total number of the first array elements is more than one, and a total number of the second array elements is more than one, a first interval, a second interval and a third interval are each set at a guide wavelength interval, the first interval being an interval between the first array elements adjacent to each other, the second interval being an interval between the second array elements adjacent to each other, the third interval being an interval between one of the first array elements and one of the second array elements adjacent to each other.
8. The apparatus according to claim 1, wherein the first slot and the at least one reflection suppressing element are formed at an interval no more than a one-quarter guide wavelength in a waveguide axial direction, and the second slot and the third slot are formed at an interval no more than the one-quarter guide wavelength in the waveguide axial direction.
9. The apparatus according to claim 1, wherein the second slot and the third slot are formed as a pair slot.
10. The apparatus according to claim 1, wherein the second slot and the third slot are formed at an interval so that reflections from each other’s slot are suppressed.
11. The apparatus according to claim 1, wherein the third slot is formed at a position which is close to the second slot than the first slot.
12. The apparatus according to claim 1, wherein the electric powers excited by all of the first and second array elements is set at uniform amplitude.
13. The apparatus according to claim 1, wherein the reflection suppressing element is a reflection suppressing post formed of conductor and inside the waveguide.
14. The apparatus according to claim 1, wherein the reflection suppressing element is a reflection suppressing wall integrated with the wall of the waveguide.
15. The apparatus according to claim 1, wherein the second slot and the third slot are offset each other in the waveguide widthwise direction.
16. The apparatus according to claim 1, wherein the first, second, and third slots are formed obliquely to the waveguide axial direction.
17. A radar apparatus, comprising:
a plurality of the antenna apparatus of claim 1;
an RF module configured to perform processing including a down-conversion which obtains a converted signal by performing frequency conversion on a signal received by the antenna unit;
an AD converter configured to generate a digital signal by performing an analog-to-digital conversion on the converted signal; and
a mono-pulse digital beam former configured to estimate a position of a target by using the digital signal.
18. The apparatus according to claim 17, wherein the waveguide comprises:
a dielectric substrate including a first surface and a second surface opposing the first surface, the first surface being covered with a first conductor, the second surface being covered with a second conductor;
a first via hole array formed by arranging, at a first spacing, a plurality of first via holes which electrically connect the first conductor and the second conductor; and
a second via hole array formed by arranging, at the first spacing, a plurality of second via holes which electrically connect the first conductor and the second conductor, the second via hole array being arranged parallel to the first via hole array at a second spacing,
the one or more first array elements are formed at a position where the coupling power ratio is no less than the threshold in a region on the first surface sandwiched between the first via hole array and the second via hole array, and the one or more second array elements are formed at a position where the coupling power ratio is less than the threshold in the region.
19. The apparatus according to claim 17, wherein when setting a first threshold and a second threshold larger than the first threshold, the one or more second array elements are forted at a position where the coupling power ratio is less than the second threshold, the one or more first array elements are formed at a position where the coupling power ratio is no less than the first threshold, and at least one of the first and second array elements are formed at a position where the coupling power ratio is no less than the first threshold and less than the second threshold.
20. The apparatus according to claim 19, wherein the first threshold is five percent and the second threshold is twenty percent.