Method and apparatus for providing dynamic focussing and beam steering in an ultrasonic apparatus

• US 4,213,344 A
• Filed: 10/16/1978
• Issued: 07/22/1980
• Est. Priority Date: 10/16/1978
• Status: Expired due to Term

• Current Assignee: Krautkramer-Branson Incorporated
• Original Assignee: Krautkramer-Branson Incorporated
• Inventors: Rose, Joseph L.
• Primary Examiner(s): Ciarlante, Anthony V.
• Application Number:
  US05/951,490
• Time in Patent Office: 645 Days
• Field of Search: 73/620, 73/642, 310/335, 340/5 MP
• US Class Current: 73/620
• CPC Class Codes: G01N 29/221 Arrangements for directing or focusing the acoustical waves electronic orientation or focusing G01N29/262; sound directing or focusing G10K11/26; mechanical steering of sound transducers or their beams G10K11/35
• CPC Class Codes: G01S 15/8918 the array being linear
• CPC Class Codes: G10K 11/30 using refraction, e.g. acoustic lenses

Abstract

An acoustic lens having nonuniform cross sectional thickness is disposed in the path of an ultrasonic energy search beam traveling from a transducer probe to an object to be examined. In an alternative embodiment the lens has at least one contoured surface. As the lens undergoes motion in a plane substantially normal to the direction of the search beam, the search beam exhibits a varying focal zone depth and beam path for providing real time ultrasonic scanning of the examined object.

Claims

1. An ultrasonic apparatus for changing the path and focal zone length of an ultrasonic energy search beam comprising:

ultrasonic energy transmitting means coupled for transmitting an ultrasonic energy search beam toward an object to be examined;

acoustic lens means interposed in the path of said search beam from said transmitting means to the object, said lens means having a contoured groove surface for changing the focal zone length and the path of said search beam, and

motive means coupled to said lens means for causing said search beam responsive to motion of said lens means in a plane substantially normal to the search beam path to change focal zone length and beam path in a predetermined scan pattern to cause a scan of the object portion in the path of said beam.

2. An ultrasonic apparatus as set forth in claim 1, said lens means having a nonuniform thickness.

3. An ultrasonic apparatus as set forth in claim 1, said motion being rotational motion.

4. An ultrasonic apparatus as set forth in claim 3, said rotational motion being at a uniform speed.

5. An ultrasonic apparatus as set forth in claim 1, said lens means being a plate.

6. An ultrasonic apparatus as set forth in claim 1, said transmitting means and the object being at a predetermined fixed distance apart.

7. An ultrasonic apparatus as set forth in claim 1, said transmitting means cyclically transmitting said search beam.

8. An ultrasonic apparatus as set forth in claim 1, said lens means including ultrasonic energy receiving means disposed for receiving echo signals from the object.

9. An ultrasonic apparatus as set forth in claim 1, said ultrasonic energy transmitting means being coupled for undergoing motion relative to the object.

10. A method of changing the path and focal zone of an ultrasonic energy search beam comprising:

transmitting an ultrasonic energy search beam toward an object to be examined;

disposing acoustic lens means having a contoured groove surface in the path of said search beam, and

causing said lens to undergo motion in a plane substantially normal to the path of said search beam for changing the focal zone length and the path of said search beam in a predetermined scan pattern to cause a scan of the object portion in the path of said beam.

11. A method as set forth in claim 10, said lens means having a nonuniform thickness.

12. A method as set forth in claim 10, said lens means being a plate.

13. A method as set forth in claim 10, said motion being rotational motion.

14. A method as set forth in claim 13, said rotational motion being at a uniform speed.