US 5,329,817 A · Ultrasonic holography imaging method and apparatus

Abstract

A preferred embodiment of this invention is illustrated in FIG. 4 showing an offset and tilted object transducer 50 being rotated about a system axis 51 to sequentially insonify the object from various acute incident angles .theta. to the system axis to provide images of the out-of-focus structures at spaced locations at the hologram detection surface 18 at different spaced times. If the pulse rate of the object transducer is greater than the fusion of the eye, the eye is able to average two or more images into a single perceived image. Likewise, video equipment that receives images at a rate greater than 30 Hertz will average two or more images and display the image at a rate of approximately 30 Hertz. Additionally, external video processing may be utilized to electronically average two or more images electronically to obtain an averaged image at any time constant desired by the operator. Such a system effectively neutralizes or blends the out-of-focus structure of an object spaced from a selected focus plane 27 while maintaining the structure within the plane in sharp consistent contrast to provide consistent, quality images of the internal structure of an object 12.

Claims30

Dependent claims

An ultrasonic holographic imaging apparatus for generating a holographic image of object structure in a selected plane of an object that is place in the path of ultrasound while minimizing holographic image distortions caused by interfering structure of the object spaced from the selected object plane defining an out-of-focus structure, comprising:

a) an ultrasonic holographic detection surface aligned with an optical axis;
b) an ultrasonic transducer means for (1) directing a coherent object beam of ultrasound along the optical axis and through the object to the ultrasonic holographic detection surface, and (2) directing a coherent ultrasonic reference beam to the holographic detection surface to interfere with the object beam to form an ultrasonic hologram at the detection surface;
c) an ultrasonic imaging lens system aligned with and extending along the optical axis between the object and the holographic detection surface for focusing ultrasound from the selected object plane onto the holographic detection surface;
and
d) wherein the ultrasonic transducer means directs the ultrasonic object beam through the object at a plurality of acute incident angles relative to the optical axis to project images of the out-of-focus structure on the detection surface at spaced locations corresponding to the acute incident angles.

2 more elements

An ultrasonic holographic imaging process for generating a holographic image of object structure in a selected plane of an object that is place in the path of ultrasound while minimizing holographic image distortions caused by interfering structure of the object spaced from the selected object plane defining an out-of-focus structure, comprising the steps of:

a) aligning an ultrasonic holographic detection surface with a system axis;
b) directing a coherent object beam of ultrasound along the system axis and through the object to the ultrasonic holographic detection surface;
c) directing a coherent ultrasonic reference beam to the holographic detection surface to interfere with the object beam to form an ultrasonic hologram at the detection surface;
d) aligning an ultrasonic imaging lens system along the system axis between the object and the holographic detection surface for focusing ultrasound from the selected object plane onto the holographic detection surface;
and
e) directing the ultrasonic object beam through the object at a plurality of acute incident angles relative to the system axis to project images of the out-of-focus structure on the detection surface at spaced locations corresponding to the acute incident angles.

3 more elements

Dependencies are inferred from the claim text.

Ultrasonic holography imaging method and apparatus

Life of this patent

Ultrasonic holography imaging method and apparatus

Life of this patent

Abstract

Claims30