Flexible Circuits
In electronic devices, circuits are connected to the keyboard by electrical contact when the keys are pressed. They help to send a digital signal through circuit connections to activate the electronic appliance. Flexible circuits are alternatives to other more common wiring methods and rigid circuit boards. They are used when space and weight are issues and are found in industrial and commercial products within the automotive, military, medical, optometry and electronics industries. Products like satellite systems, security devices, car radios, cassette players, electronic control systems, hard disk drives, printers, pacemakers and hearing aids use flexible circuits. Since they are so thin, many are multi-layer and have different coatings.
These circuits are generally made of a flexible polymer film and sometimes coated with a polymer for electrical insulation and protection from liquid and dirt. They are laminated to etched metal with a circuit pattern and are able to conform to many different environments, even three dimensional. They increase the circuit density, cut down on bulky connections and wiring, and are able to last a long time. However, they are more expensive and fragile than their alternatives, and are subject to tearing. Flexible circuits are made to bend, fold, twist and wrap to conform to all sorts of different circuit boards.