Ultrasonic measurement method, and apparatus therefor

• US 4,566,330 A
• Filed: 10/02/1984
• Issued: 01/28/1986
• Est. Priority Date: 12/07/1983
• Status: Expired due to Fees

• Current Assignee: Terumo Kabushiki Kaisha (Terumo Corporation)
• Original Assignee: Terumo Kabushiki Kaisha (Terumo Corporation)
• Inventors: Fujii, Tadashi, Hayakawa, Yoshinori
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US06/657,028
• Time in Patent Office: 483 Days
• Field of Search: 73/599, 73/1 DV, 73/600, 73/602, 73/606, 73/607, 73/620, 73/629, 128/660
• US Class Current: 73/599
• CPC Class Codes: G01N 29/11 by measuring attenuation of acoustic waves
• CPC Class Codes: G01N 29/348 with frequency characteristics, e.g. single frequency signals, chirp signals measuring frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04; measuring frequency or analysing frequency spectra G01R23/00
• CPC Class Codes: G01S 15/8952 using discrete, multiple frequencies
• CPC Class Codes: G01S 7/52036 using analysis of echo signal for target characterisation

Abstract

A method and apparatus for ultrasonic measurement in which ultrasonic pulses having a plurality of different frequencies are transmitted into in order to object under investigation and derive a mean value of attenuation coefficients indicative of attenuation within the object, as well as the frequency dependence of the attenuation coefficient. If the frequency dependence of the reflection intensity from the object under investigation is constant or proportional to frequency within a range of measured frequencies, it is possible to obtain the attenuation coefficient and the coefficient indicative of its frequency dependence within a small area of the object by measuring the echo intensity of emitted ultrasonic pulses having three different frequencies. Furthermore, extending the above-mentioned processing over all small areas of the entire object enables obtaining a two-dimensional distribution image indicative of the attenuation coefficient and its frequency dependence.

Claims

1. An ultrasonic measurement method for obtaining quantitative information relating to ultrasonic characteristics of an object under investigation, comprising the steps of:

(a) transmitting ultrasonic pulses having a plurality of different frequencies into the object under investigation,

(b) detecting echos of the ultrasonic pulses reflected from within the object,

(c) subjecting the detected echos, which exhibit a plurality of frequencies, to information processing to derive a mean value of attenuation coefficients measured on the basis of two different frequencies, and a mean value of attenuation coefficients measured on the basis of three different frequencies inclusive of the first two frequencies; and

(d) deriving information relating to an attenuation coefficient of the object from said mean value of attenuation coefficients measured on the basis of two different frequencies, and said mean value of attenuation coefficients measured on the basis of three different frequencies inclusive of the first two frequencies.

2. The method according to claim 1, wherein the information relating to the attenuation coefficient includes an attenuation coefficient of ultrasonic waves within the object.

3. The method according to claim 1, wherein the information relating to the attenuation coefficient includes frequency dependence of the attenuation coefficient of ultrasonic waves within the object.

4. The method according to claim 2, wherein the information relating to the attenuation coefficient includes frequency dependence of the attenuation coefficient of ultrasonic waves within the object.

5. An ultrasonic measurement method for obtaining quantitative information relating to ultrasonic characteristics of an object under investigation, comprising the steps of:

(a) transmitting ultrasonic pulses having a plurality of different frequencies into the object under investigation,

(b) detecting echos of the ultrasonic pulses reflected from within the object,

(c) subjecting the detected echos, which exhibit a plurality of frequencies, to information processing to derive a mean value of attenuation coefficients measured on the basis of two different frequencies, and a mean value of a function of both attentuation coefficients and frequencies measured on the basis of three different frequencies inclusive of the first two frequencies; and

(d) deriving information relating to an attenuation coefficient of the object from said mean value of attenuation coefficients measured on the basis of two different frequencies and said mean value of a function of both attentuation coefficients and frequencies measured on the basis of three different frequencies inclusive of the first two frequencies.

6. The method according to claim 5, wherein the information relating to the attenuation coefficient includes an attenuation coefficient of ultrasonic waves within the object.

7. The method according to claim 5, wherein the information relating to the attenuation coefficient includes frequency dependence of the attenuation coefficient of ultrasonic waves within the object.

8. The method according to claim 6, wherein the information relating to the attenuation coefficient includes frequency dependence of the attenuation coefficient of ultrasonic waves within the object.

9. An ultrasonic measurement apparatus comprising:

transmitting means for transmitting ultrasonic pulses having a plurality of different frequencies into an object under investigation;

detection means for detecting echos of the ultrasonic pulses reflected from within the object;

processing means for subjecting the detected echos, which exhibit a plurality of frequencies, to information processing to obtain quantitative information relating to ultrasonic characteristics of the object, wherein said processing means includes means for obtaining a mean value of attenuation coefficients having two different frequencies, and a mean value of attenuation coefficients having three different frequencies inclusive of the first two frequencies, and means for deriving information relating to an attenuation coefficient of the object on the basis of the mean values obtained; and

display means for displaying said quantitative information in addition to a tomograph.

10. An ultrasonic measurement apparatus comprising:

transmitting means for transmitting ultrasonic pulses having a plurality of different frequencies into an object under investigation;

detection means for detecting echos of the ultrasonic pulses reflected from within the object;

processing means for subject the detected echos, which exhibit a plurality of frequencies, to information processing to obtain quantitative information relating to ultrasonic characteristics of the object, wherein said processing means includes means for obtaining a mean value of attenuation coefficients measured on the basis of two different frequencies, and a value of a function of mean values of both attenuation coefficients and frequencies having three different frequencies inclusive of the first two frequencies, and means for deriving information relating to an attenuation coefficient of the object on the basis of the mean values obtained; and

display means for displaying said quantitative information in addition to a tomograph.