Exclusive Acoustic Metamaterial from
Murata Manufacturing –
Ultrasound Transmission Metamaterial
technology that enhances the ultrasound
transmission through materials We are seeking collaborative partners interested in leveraging ultrasound transmission metamaterial
to enhance the capabilities of their devices and explore new market opportunities.

Ordinarily, when ultrasonic waves encounter a substance that differs from the medium and has a different acoustic impedance, they are reflected rather than passing through.
For example, when you undergo an ultrasound scan of your abdomen, the technician will first apply a jell to your skin. This is done to eliminate the difference in acoustic impedance. Murata’s acoustic metamaterials, in contrast, are able to increase the transmission rate of ultrasonic waves even with substances having different acoustic impedances. This means that it may someday be possible to undergo much more comfortable ultrasound scans, without the need to apply cold, unpleasant jells.

*Click here for more information on "acoustic impedance"

The key technical point that enables the ultrasound transmission metamaterial to assist ultrasonic waves in passing through substances is the use of a resonating mechanism of "mass and spring" based structures.
Ultrasmall unit cells arranged periodically and each consisting of a mass and spring, are designed to oscillate at the resonance frequency of the incident ultrasonic waves. This allows ultrasonic waves to be transmitted efficiently even when passing through a substance such as metal with a different acoustic impedance.
By designing unit cells compatible with the difference in acoustic impedance between the substance and the medium, Murata Manufacturing has made it possible for ultrasonic waves to be transmitted through many different types of substances.

Murata’s exclusive metamaterial has the following three features.

• 1.Amazing acoustic properties (high ultrasound transmittance)
• 2.Ability to transmit the ultrasound from both sides of the acoustic metamaterial (patent pending in U.S.)
• 3.Applicable to large acoustic impedance differences

Utilizing the property of ultrasound transmission metamaterial technology to improve the transmission of ultrasound through materials, the range of applications is broad, including the biomedical and healthcare fields and the marine field.

Biomedical and health-care areas

Ultrasonic waves have many applications in the medical field, including ultrasonic imaging and diagnosis and the use of ultrasonic waves in treatment. Combining medical equipment and ultrasound transmission metamaterial holds the potential to enable development of new testing methods that are less burdensome to patients.

Marine applications

For example, ultrasound transmission metamaterial could make possible nondestructive inspection of underwater cables, etc., from above the protective covering. They have the potential to reduce the workload associated with inspection of underwater objects in seas and rivers.

Automotive applications

By using ultrasound transmission metamaterial, ultrasonic sensors can be placed behind the bumper, and a harmonious blend of vehicle aesthetics and safety measures can be achieved simultaneously.