Tri-laminar Pyroelectric Sensor for Phase-Insensitive Ultrasound Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current ultrasound sensors for medical imaging, particularly in breast cancer screening, face challenges such as radiation exposure, patient discomfort due to tissue compression, and limited image quality due to phase-sensitive sensors and imaging artefacts, which hinder the detection of breast cancer, especially in women with dense breasts.
Innovation Solution
A tri-laminar ultrasound sensor structure comprising first and second pyroelectric layers separated by an electrically insulating spacer layer, optimized for phase-insensitive detection, which reduces artefacts and enhances image quality by generating differential signals that are less affected by vibration and acoustic noise, allowing for improved tissue imaging without compression.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Difficulty of detecting and measuring
If phase-sensitive ultrasound sensors are used for tissue imaging, then detection capability is improved, but image quality deteriorates due to imaging artefacts caused by phase distribution alterations from tissue inhomogeneities
Solution Approach 1:
The patent inverts the conventional phase-sensitive detection approach by using phase-insensitive pyroelectric sensors that detect acoustic power or time-averaged ultrasound intensity instead. This inversion eliminates artefacts caused by phase distribution alterations from tissue inhomogeneities, thereby improving image quality while maintaining detection capability through alternative physical measurement principles.
Solution Approach 2:
The patent changes the detection parameter from phase-sensitive measurement to phase-insensitive measurement of acoustic power or time-averaged ultrasound intensity. This parameter change fundamentally alters how ultrasound interactions with tissue are measured, eliminating the artefact problem associated with phase distribution variations while preserving the ability to detect tissue characteristics.
2Measurement precision
If compression is applied to improve image quality by reducing tissue overlap, then measurement precision is improved, but patient comfort deteriorates due to discomfort and pain
Solution Approach 1:
The patent replaces the mechanical compression system with a non-contact or minimal-contact ultrasound imaging approach using phase-insensitive pyroelectric sensors. This substitution eliminates the need for breast compression between plates, thereby maintaining image quality through improved artefact reduction while completely removing the source of patient discomfort and pain associated with mechanical compression.
3Measurement precision
If multiple images at different angles are obtained to improve detection accuracy, then measurement precision is improved, but radiation exposure increases proportionately
Solution Approach 1:
The patent substitutes X-ray based imaging with ultrasound imaging using phase-insensitive pyroelectric sensors, eliminating ionizing radiation entirely. The system achieves detection accuracy through improved image quality via artefact reduction and potentially through mechanical rotation or array scanning, but without the cumulative radiation exposure inherent in acquiring multiple angular X-ray images.
4Productivity
If pyroelectric sensors operate with fast response time, then productivity is improved, but sensitivity to vibration and acoustic noise increases
Solution Approach 1:
The patent converts the harmful sensitivity to vibration and acoustic noise into a beneficial feature by using differential measurement between two pyroelectric sensors. The vibration and acoustic noise affect both sensors equally, so taking the difference cancels out these common-mode disturbances while preserving the useful ultrasound signal, thereby achieving fast response time without the penalty of noise sensitivity.
Solution Approach 2:
The patent implements a differential measurement feedback system where the output of one pyroelectric sensor is compared with the other. This feedback mechanism continuously compensates for vibration and acoustic noise by subtracting the common-mode signals, allowing the system to maintain fast response time while effectively rejecting environmental noise interference.
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
The solution provides enhanced image quality and reduced patient discomfort by improving signal-to-noise ratio and response speed, enabling more accurate and comfortable breast cancer screening with reduced radiation exposure, suitable for both medical and non-medical applications.
Implementation Method 1
Sensors operating on pyroelectric principles are an example of such a phase-insensitive sensor
Data Source
AI summary
A sensor or receiver array includes first and second pyroelectrically active electrodes formed of polyvinylidene difluoride and separated by a spacer layer that acts to electrically separate the pyroelectric layers while keeping them close enough such that they see effectively the same vibration or background acoustic excitation while maintaining sufficient separation to ensure that they generate significant differences in their pyroelectric responses. The structure provides two distinct signals (at separate timestamps), the difference between which provides a more accurate signal. An ultrasound detection system includes the tri-laminar sensor, disposed within a detection zone in which a test element can be positioned. The apparatus includes a processing unit, which comprises a detector unit coupled to the first and second pyroelectric elements and configured to derive a differential signal from the first and second pyroelectric elements. A processor is coupled to the detector unit and is configured to generate an electrical output waveform on the basis of the data extracted from first and second pyroelectric elements.