Ultrasonic Imaging Reference Signal Switching

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The pulse-echo method used in ultrasonic diagnostic apparatuses faces limitations in achieving high depth-direction spatial resolution due to changes in the waveform of transmitted acoustic waves at different positions within an object, leading to potential cancellation of desired signals and deterioration of image quality when using FDI-employed adaptive signal processing.

Innovation Solution

An object information acquisition apparatus that switches the reference signal at least once according to the depth inside the object during FDI-employed adaptive signal processing, using a plurality of reference signals with different waveforms to match the changing acoustic waveforms at various positions, thereby improving spatial resolution.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If FDI-employed adaptive signal processing is performed using a single reference signal, then spatial resolution is improved at the reference signal's waveform-matched position, but spatial resolution deteriorates at other positions where the transmitted acoustic wave waveform differs

Engineering Contradiction:
Improvespatial resolutionVSAvoidposition independence of spatial resolution
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The patent applies dynamics by switching the reference signal based on the depth position within the object. Instead of using a fixed reference signal, the system dynamically selects different reference signals corresponding to different depth regions, allowing the reference signal waveform to adapt to the changing transmitted acoustic wave characteristics at each position, thereby maintaining high spatial resolution throughout the entire imaging depth range

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent segments the imaging depth range into multiple regions, with each region having its own optimized reference signal. By dividing the deep imaging space into shallower and deeper regions (or multiple depth zones), each with locally optimized reference signals matched to the transmitted waveform characteristics in that region, the system achieves high spatial resolution across all segments rather than just at a single reference position

Inventive Principle:
Principle #1Segmentation

2Measurement precision

If the waveform of the transmitted acoustic wave changes at different positions, then the reference signal can be optimized for a specific position, but signal cancellation occurs at other positions leading to image quality deterioration

Engineering Contradiction:
Improvespatial resolution at specific positionVSAvoidimage quality consistency
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent changes the reference signal parameters (specifically the waveform characteristics) according to the depth position. By adjusting the reference signal to match the transmitted acoustic wave waveform at each depth region, the system prevents signal cancellation effects that would otherwise occur when using a mismatched reference signal, thereby maintaining consistent image quality and spatial resolution across different positions

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach stabilizes high spatial resolution by adapting the reference signal to the changing waveforms, ensuring that the spatial resolution is maintained across different depths within the object, enhancing the quality of acquired image data.

Implementation Method 1

a plurality of transducer elements 002 each configured to perform conversion between an ultrasonic wave and an electric signal

Methodology Applied
Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

The ultrasonic wave pulse is then reflected because of a difference in acoustic impedance inside the object, and a reflected wave returns

Methodology Applied
Scientific EffectAcoustic reflection: Reflection

Implementation Method 3

a result obtained by imaging of the layered structure of the blood vessel wall by performing frequency domain interferometry (hereinafter, referred to as FDI method)

Methodology Applied
Scientific EffectFrequency domain interferometry: Interference

Data Source

PatentEP2793048B1Ultrasonic imaging apparatus, ultrasonic imaging method, and program
Publication Date: 2019.12.18 CANON KK
  • EP2793048B1 patent drawingFigure 1
  • EP2793048B1 patent drawingFigure 2
  • EP2793048B1 patent drawingFigure 3

AI summary

An object information acquisition apparatus according to an embodiment of the present invention includes a plurality of transducer elements (002) each configured to transmit an acoustic wave to an object (000), to receive reflected waves reflected from inside the object (000), and to convert the reflected waves into a time-series reception signal; and processing means (007, 009) configured to perform frequency domain interferometry combined with adaptive signal processing by using the reception signals output from the plurality of transducer elements (002) and a reference signal so as to obtain acoustic characteristics at a plurality of positions located inside the object (000). The processing means (007, 009) is configured to switch the reference signal to another reference signal at least once in accordance with a target position located inside the object (000) while performing the frequency domain interferometry so as to obtain the acoustic characteristics at the plurality of positions located inside the object (000) .