Cell Phone Radiation
How Do RF Safe Flip Cover Radiation Shields Work? – Technology Review
Jun
1. Materials Used for Shielding Electromagnetic Radiation
1(a) RF Shielded fabric is made from polyester filaments woven with a blend of micro-fine conductive threads. The shielding fabric is than combined with a proprietary layer of CR foam rubber designed to keep your phones display screen looking like new while deflecting potentially harmful radiation away.
1(b) Hypoallergenic silver plated RF Shielding Mesh is used around the earpiece speaker hole to eliminate the chances of any skin reactions to metal alloys commonly used in RF Shielding Materials. Conductive adhesive is used to seamlessly layer the silver shielding mesh and shielded foam together in full compliance of EU Nickel Directive 94/27/EC
2. How RF Shielding Deflects Electromagnetic Radiation
Electromagnetic radiation consists of coupled electric and magnetic fields. The electric field produces forces on the charge carriers (i.e., electrons) within the conductor. As soon as an electric field is applied to the surface of an ideal conductor, it induces a current that causes displacement of charge inside the conductor that cancels the applied field inside, at which point the current stops.
Similarly, varying magnetic fields generate eddy currents that act to cancel the applied magnetic field. (The conductor does not respond to static magnetic fields unless the conductor is moving relative to the magnetic field.) The result is that electromagnetic radiation is reflected from the surface of the conductor: (Image 2)
See RF Flip Case In Action Blocking Cell Phone Radiation From Galaxy Note 4
As you can see, even though this cell phone has a low SAR — when we measure the “real radiation” coming from the device we see it is still very high over ambient levels.
That is the “Actual RF Exposure” that people are exposed measuring even non-thermal levels not addressed under current FCC SAR guidelines. Measuring actual RF emissions is a much more prudent way for consumers to gauge their true levels of microwave exposure; as SAR testing only measures heating potential. ie “the by-product” of too much RF exposure to begin with.
