Shielded Ultrasound Transducer for EMI Protection

Solution Overview

Problem

Medical imaging systems employing ultrasound face interference issues due to electromagnetic and radio-frequency emissions, particularly in thermoacoustic imaging where high-energy electromagnetic pulses generate significant electric fields, leading to signal interference and potential damage to electronics.

Innovation Solution

A shielded ultrasound transducer design featuring a shield with acoustic conductivity and electrical attenuation characteristics that reduces a 100 V/cm electric field to below a threshold level, exposing the piezoelectric element to electrical potentials of 10 μV or less, using elastic conductive materials or cage-like structures to minimize interference while preserving acoustic signal amplitude.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If traditional shielding methods are used in ultrasound transducers, then electromagnetic interference protection is provided, but acoustic signal transmission is significantly attenuated

Engineering Contradiction:

Improveelectromagnetic interference protectionVSAvoidacoustic signal transmission

Core Design Contradiction:

Object-affected harmful factorsVSLoss of energy

Solution Approach 1:

The patent applies local quality by using different materials for different parts of the shielding structure. The housing uses a non-conductive material (plastic or ceramic) while the shield uses a conductive material (metal or conductive polymer). This localized differentiation allows the non-conductive housing to transmit acoustic signals while the conductive shield provides EMI protection, resolving the contradiction between shielding effectiveness and acoustic transmission.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs composite materials by combining conductive and non-conductive materials in a single transducer assembly. The housing is made of non-conductive material for acoustic transparency, while the shield is made of conductive material for EMI protection. This composite approach allows each material to perform its optimal function without compromising the other, simultaneously achieving both acoustic signal transmission and electromagnetic interference protection.

Inventive Principle:

Principle #40Composite materials

2Loss of energy

If no shielding is used to maintain acoustic signal transmission, then acoustic signals pass through freely, but electromagnetic and radio-frequency interference damage electronics and cause imaging inaccuracies

Engineering Contradiction:

Improveacoustic signal transmissionVSAvoidelectromagnetic and radio-frequency interference

Core Design Contradiction:

Loss of energyVSObject-affected harmful factors

Solution Approach 1:

The patent applies local quality by using different materials for different parts of the shielding structure. The housing uses a non-conductive material (plastic or ceramic) while the shield uses a conductive material (metal or conductive polymer). This localized differentiation allows the non-conductive housing to transmit acoustic signals while the conductive shield provides EMI protection, resolving the contradiction between shielding effectiveness and acoustic transmission.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs composite materials by combining conductive and non-conductive materials in a single transducer assembly. The housing is made of non-conductive material for acoustic transparency, while the shield is made of conductive material for EMI protection. This composite approach allows each material to perform its optimal function without compromising the other, simultaneously achieving both acoustic signal transmission and electromagnetic interference protection.

Inventive Principle:

Principle #40Composite materials

3Object-affected harmful factors

If thicker shielding material is used to block electromagnetic interference, then EMI protection is improved, but acoustic signal attenuation increases

Engineering Contradiction:

Improveelectromagnetic interference protectionVSAvoidacoustic signal accuracy

Core Design Contradiction:

Object-affected harmful factorsVSMeasurement precision

Solution Approach 1:

The patent applies local quality by using different materials for different parts of the shielding structure. The housing uses a non-conductive material (plastic or ceramic) while the shield uses a conductive material (metal or conductive polymer). This localized differentiation allows the non-conductive housing to transmit acoustic signals while the conductive shield provides EMI protection, resolving the contradiction between shielding effectiveness and acoustic transmission.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs composite materials by combining conductive and non-conductive materials in a single transducer assembly. The housing is made of non-conductive material for acoustic transparency, while the shield is made of conductive material for EMI protection. This composite approach allows each material to perform its optimal function without compromising the other, simultaneously achieving both acoustic signal transmission and electromagnetic interference protection.

Inventive Principle:

Principle #40Composite materials

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

Effectively shields the ultrasound transducer from electromagnetic and radio-frequency interference, preventing signal interference and potential damage, while maintaining minimal acoustic signal attenuation, ensuring accurate imaging in high EMI and RFI environments.

Implementation Method 1

the shield having acoustic conductivity and electrical attenuation characteristics that enable the acoustic signals to propagate therethrough while reducing a 100 volt per centimeter electric field to below a threshold level

Methodology Applied

Scientific EffectElectromagnetic attenuation: Absorption (EM radiation)

Implementation Method 2

at least one piezoelectric element configured to convert received acoustic signals into an electric potential

Methodology Applied

Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 3

enable the acoustic signals to propagate therethrough

Methodology Applied

Scientific EffectAcoustic wave propagation: Sound

Data Source

PatentUS10888898B2Shielded ultrasound transducer and imaging system employing the same

Publication Date: 2021.01.12 ENDRA LIFE SCIENCES INC

AI summary

An ultrasound transducer with at least one piezoelectric element configured to convert received acoustic signals into an electric potential, a shield connectable to ground and overlying the at least one piezoelectric element through which the acoustic signals pass before being received by the at least one piezoelectric element, the shield having acoustic conductivity and electrical attenuation characteristics that enable the acoustic signals to propagate therethrough while reducing a 100 volt per centimeter electric field to below a threshold level so that the piezoelectric element is exposed to a threshold electrical potential at least less than or equal to 10 μV, and a housing accommodating the at least one piezoelectric element and shield.