US4471785A — Ultrasonic imaging system with correction for vel…

Claim 1

Independent Claim 87 words

An ultrasonic imaging system comprising an array of transducer elements for receiving ultrasonic signals reflected from within an object being examined, means connected to generate an image in response to the ultrasonic signals, means connected to compare the signals received by the transducer elements by means of a cross-correlation among the signals, and means connected to modify amplitude of selected ones of the signals based on the comparison to correct image distortion, said signal modifying means being connected between said transducer elements and said image generating means.

Claim 2

Dependent Claim 87 words

An ultrasonic imaging system comprising an array of transducer elements for receiving ultrasonic signals reflected from within an object being examined, means connected to generate an image in response to the ultrasonic signals, means connected to compare the signals received by the transducer elements by means of a cross-correlation among the signals, and means connected to modify amplitude of selected ones of the signals based on the comparison to correct image distortion, said signal modifying means being connected between said transducer elements and said image generating means.

Claim 3

Dependent Claim 70 words

The ultrasonic imaging system of claim 1 in which each of said transducer elements is connected to supply its ultrasonic signals to a delay means, and the cross-correlation signal comparison of said comparison means is further utilized to adjust the length of delay of at least one of said delay means so that the ultrasonic signals are supplied substantially in phase with respect to one another from said delay means.

Claim 4

Dependent Claim 25 words

The ultrasonic imaging system of claim 1 in which the selected ones of the signals are modified by apodizing the selected ones of the signals.

Claim 5

Dependent Claim 34 words

The ultrasonic imaging system of claim 1 in which the image distortion is from multipath ultrasonic signal interference, refraction of the ultrasonic signals away from the transducer elements, or obstruction of the ultrasonic signals.

Claim 6

Dependent Claim 152 words

An ultrasonic imaging system for an inhomogeneous medium comprising a segmented annular array of transducer elements for receiving ultrasonic signals reflected from within the inhomogeneous medium being examined, each of the annular segments being formed as sectors of circles, the sectors having substantially equal arc lengths, a plurality of signal delay means, one of said plurality of delay means being connected to receive the ultrasonic signals from a respective one of the transducer elements of said array, means also connected to receive the ultrasonic signals from each transducer element in said array for determining differences in delay for each signal from inhomogeneities within the medium and for adjusting a length of delay of at least one of said plurality of delay means based on the delay differences so that the ultrasonic signals are provided as substantially in phase outputs with respect to one another from each of said plurality of delay means.

Claim 7

Dependent Claim 152 words

An ultrasonic imaging system for an inhomogeneous medium comprising a segmented annular array of transducer elements for receiving ultrasonic signals reflected from within the inhomogeneous medium being examined, each of the annular segments being formed as sectors of circles, the sectors having substantially equal arc lengths, a plurality of signal delay means, one of said plurality of delay means being connected to receive the ultrasonic signals from a respective one of the transducer elements of said array, means also connected to receive the ultrasonic signals from each transducer element in said array for determining differences in delay for each signal from inhomogeneities within the medium and for adjusting a length of delay of at least one of said plurality of delay means based on the delay differences so that the ultrasonic signals are provided as substantially in phase outputs with respect to one another from each of said plurality of delay means.

Claim 8

Dependent Claim 45 words

The ultrasonic imaging system of claim 5 in which the transducer elements in said array are substantially isolated electrically and acoustically from one another, and said plurality of delay lines are connected to supply the output substantially in phase ultrasonic signals to a summing means.

Claim 9

Dependent Claim 29 words

The ultrasonic imaging system of claim 5 in which the differences in delay for each signal are determined through use of a plurality of cross-correlation values for each signal.

Claim 10

Dependent Claim 49 words

An ultrasonic imaging array comprising a plurality of segmented, annular transducer elements, said elements being formed as sectors of circles arranged in a plurality of concentric, circular rows, with the sectors of each circular row each having substantially equal arc lengths to the sectors of the remaining circular rows.

Claim 11

Dependent Claim 49 words

An ultrasonic imaging array comprising a plurality of segmented, annular transducer elements, said elements being formed as sectors of circles arranged in a plurality of concentric, circular rows, with the sectors of each circular row each having substantially equal arc lengths to the sectors of the remaining circular rows.

Claim 12

Dependent Claim 16 words

The ultrasonic imaging array of claim 8 additionally comprising a centrally disposed, undivided circular transducer element.

Claim 13

Dependent Claim 37 words

The ultrasonic imaging array of claim 8 in which said sector elements in successive rows overlap, so that said array is free of any straight line gap extending from a periphery to a center of said array.

Claim 14

Dependent Claim 167 words

A signal processing circuit for use with an ultrasonic imaging system, which system includes an array of transducer elements, which comprises a delay memory means having for each transducer element, a separate input and output, the inputs being connected to receive information signals representing ultrasonic signals sensed by each element of the array, a separate buffer memory for each element of the array also connected to receive the information signals representing ultrasonic signals sensed by each element of the array, means connected to receive stored information based on the information signals from said buffer memories for at least two of the elements of the array and to determine a correlation between the ultrasonic signals for the at least two elements of the array, and control means connected between said correlation determining and said delay memory means to control presentation of information outputs from said delay memory means based on the correlation so that the information outputs are presented as substantially in phase representations of the ultrasonic signals.

Claim 15

Dependent Claim 167 words

A signal processing circuit for use with an ultrasonic imaging system, which system includes an array of transducer elements, which comprises a delay memory means having for each transducer element, a separate input and output, the inputs being connected to receive information signals representing ultrasonic signals sensed by each element of the array, a separate buffer memory for each element of the array also connected to receive the information signals representing ultrasonic signals sensed by each element of the array, means connected to receive stored information based on the information signals from said buffer memories for at least two of the elements of the array and to determine a correlation between the ultrasonic signals for the at least two elements of the array, and control means connected between said correlation determining and said delay memory means to control presentation of information outputs from said delay memory means based on the correlation so that the information outputs are presented as substantially in phase representations of the ultrasonic signals.

Claim 16

Dependent Claim 31 words

The signal processing circuit of claim 11 in which said correlation determining means comprises a microcomputer and said control means comprises a means for supplying addresses to said delay memory means.

Claim 17

Dependent Claim 68 words

The signal processing circuit of claim 11 in which said delay memory means receives a plurality of the information signals at different times as a result of different times at which the ultrasonic signals are sensed by the elements of the array and said control means causes said delay memory means to present a corresponding plurality of the information outputs substantially in phase with respect to one another.

Claim 18

Dependent Claim 66 words

The signal processing circuit of claim 11 in which said control means causes said delay memory means to modify gain of selected ones of the plurality of information outputs for which the correlation of the corresponding stored information determined by said correlation determining means varies by more than a predetermined amount from the correlations for the corresponding stored information for other ones of said information outputs.

Claim 19

Dependent Claim 31 words

The signal processing circuit of claim 14 in which the gain of the selected ones of the plurality of information outputs is modified by eliminating the selected ones of the outputs.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1987-09-18	1988-03-19	1988-09-18	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1991-09-18	1992-03-19	1992-09-18	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1995-09-18	1996-03-19	1996-09-18	$7700.00	Window Closed / Lapsed

Ultrasonic imaging system with correction for velocity inhomogeneity and multipath interference using an ultrasonic imaging array

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