Flexible broadband microshield for electromagnetic interference and electrostatic discharge
AssigneeApple Inc.
InventorHenry M. Daghighian
Life of this patent
Estimating the term…
Abstract
A multilayer shield is used as an absorber for attenuating electromagnetic radiation (e.g., EMI) includes both metal and ferrite powder layers. Radiation transmitted through one of the metal layers be transmitted to an additional metal layer, and the radiation can be reflected between the metal layers. While reflected by the metal layers, the radiation is absorbed by one of the ferrite powder layers positioned between the metal layers, causing the ferrite powder layer to convert the radiation to thermal energy. Based on energy losses of the radiation due to reflection and thermal energy conversion, the radiation is sufficiently attenuated to limit disruption of nearby transmission signals, including high frequency transmission signals.
Claims20
An assembly, comprising:
- a first shield, comprising:
- a first metal layer;
- a second metal layer coupled to the first metal layer, the second metal layer comprising ferrite powder;
- and
- a third metal layer coupled to the second metal layer, wherein in response to receiving electromagnetic radiation (EMR) energy:
- the first metal and the second metal are configured to reflect a first amount of the EMR energy transmitted through the first metal layer, and
- the ferrite powder is configured to absorb at least some of the first amount of EMR energy and convert the absorbed EMR energy into thermal energy;
- a flexible circuit comprising:
- a dielectric material, and
- transmission lines positioned in the dielectric material;
- and
- a first ground plane positioned between the first shield and the flexible circuit;
- and
- a second shield, wherein the flexible circuit is positioned between the first shield and the second shield.
An electronic device, comprising:
- a circuit board;
- an image sensor;
- a flexible circuit electrically coupled to the circuit board and the image sensor;
- and
- a shield first positioned on a surface of the flexible circuit, the first shield comprising:
- a first metal layer comprising a first metal;
- a second metal layer coupled to the first layer, the second layer comprising a first plurality of ferrite powder;
- and
- a third metal layer coupled to the second layer, the third layer comprising a second metal, wherein in response to receiving electromagnetic radiation (EMR) energy:
- the first metal and the second metal are configured to reflect a first amount of the EMR energy transmitted through the first metal layer, and
- the ferrite powder is configured to absorb at least some of the first amount of EMR energy and convert the absorbed EMR energy into thermal energy;
- a flexible circuit comprising:
- a dielectric material, and
- transmission lines positioned in the dielectric material;
- and
- a first ground plane positioned between the first shield and the flexible circuit;
- and
- a second shield, wherein the flexible circuit is positioned between the first shield and the second shield.
Dependencies are inferred from the claim text.