In medical environments, electromagnetic interference (EMI) and radio frequency interference (RFI) can disrupt signal integrity, leading to data inaccuracies, communication errors, and device malfunctions. These risks are particularly critical in systems that rely on precise sensor feedback, such as robotic-assisted surgical devices.
To maintain signal reliability, medical devices require effective EMI/RFI shielding that prevents both external interference and unintended signal emission.
How Does EMI Shielding Work?
EMI shielding works by creating a conductive barrier around sensitive components, allowing electromagnetic energy to be redirected or absorbed rather than interfering with device operation. In many cases, this barrier functions similarly to a Faraday cage, enclosing electronics to isolate them from external noise.
Common coating methods used to achieve EMI/RFI shielding include:
- Vacuum Metallization. Applies thin metallic layers (e.g., aluminum) to non-conductive surfaces to create a conductive shielding layer.
- Multi-Layer Coatings. Combines metals such as copper, nickel, or chrome to optimize conductivity, corrosion resistance, and shielding effectiveness.
- Conductive Sprays. Applies nickel- or silver-based coatings to complex geometries where other processes may not achieve full coverage.
RFI shielding operates under the same principles, using conductive coatings to limit interference from radio-frequency signals generated by nearby electronic systems.
Importance of EMI/RFI Shielding in the Medical Industry
Medical environments often contain multiple electronic systems operating in close proximity, including imaging equipment, diagnostic tools, and surgical devices. This high-density environment increases the likelihood of electromagnetic interference affecting device performance.
To function reliably, medical devices must meet electromagnetic compatibility (EMC) requirements, meaning they must both resist external interference and limit the signals they emit. EMI/RFI shielding coatings play a key role in achieving these standards.
Without proper shielding, interference can lead to signal distortion, delayed response times, or device failure during critical procedures. Effective shielding helps maintain consistent performance in high-risk environments.
Fisher Barton’s EMI/RFI Shielding Coatings
Fisher Barton, through its TST Engineered Coating Solutions division, develops EMI and RFI shielding coatings for medical device applications requiring controlled signal integrity. Depending on each application’s specific requirements, we’ll develop a fully customized solution that meets your needs.
These coatings are applied to substrates such as polymers and composites to create conductive surfaces that reduce both emitted and received electromagnetic interference.
Thermal spray coating processes are used to apply these materials. In this process, coating material is melted using electrical energy or combustion and propelled onto a prepared surface, forming a uniform conductive layer.
In addition to EMI/RFI shielding, Fisher Barton also develops dielectric coatings for applications requiring electrical insulation. These coatings are often used in bipolar medical devices where controlled current flow is critical.
Improving Signal Integrity in Medical Devices with EMI/RFI Shielding
EMI/RFI shielding coatings help maintain signal integrity by preventing interference between adjacent electronic systems. This is critical in environments where multiple devices operate simultaneously within confined spaces.
These coatings can be tailored to specific device geometries, materials, and performance requirements. Additional coating solutions, including dielectric and biocompatible coatings, can be integrated based on application needs.
Contact Fisher Barton to discuss your application requirements and determine the appropriate coating strategy for managing EMI and RFI in your medical devices.