What Is an Electromagnetic Wave Absorption Sheet?
An electromagnetic wave absorption sheet is one of the most commonly used EMC countermeasures for electronic equipment that generates electromagnetic waves or performs switching operations that may cause malfunctions due to exposure to electromagnetic waves, such as noise terminal voltage and disturbance power.
It is one of the most common EMC countermeasure items used in electronic equipment. Generally, the sheet is made of resin or rubber. The sheets can be cut into desired shapes and are inexpensive, lightweight, and easy to use, making them an indispensable part of EMC countermeasures.
Uses of Electromagnetic Wave Absorption Sheets
An electromagnetic wave absorption sheet is mainly used as a countermeasure against EMC standards, as described in the overview.
EMC is a generally used sheet to suppress the noise within the regulation values or to block the noise when the product malfunctions due to external noise.
Principle of Electromagnetic Wave Absorption Sheets
An electromagnetic wave absorption sheet utilizes the property of the magnetic material woven into the sheet to absorb electromagnetic waves and convert them into heat energy inside the sheet. Although the use of electromagnetic wave absorbers is not known, they are used in a wide range of fields, including shortwave broadcasting below 30 MHz as a countermeasure against communication interference in ship and aviation radios, and in the 30 MHz to 300 GHz band for FM, TV, cell phones, overseas satellite broadcasting, and personal radios, which are all widely used in society.
In addition, electromagnetic wave absorption sheets are used in a much wider range of applications than one might imagine, including microwave relay and various types of radar.
It is not well known that electromagnetic wave absorbing materials convert absorbed electromagnetic wave energy into heat energy, but there are different types of electromagnetic wave absorbing materials. It is classified according to the aforementioned balance of electromagnetic waves versus the bandwidth. Therefore, it is an important factor in material selection when using electromagnetic wave absorption sheets to select an absorber that is effective in the frequency band used for home appliances and for satellite communications in the frequency band used for satellite broadcasting.