Flexible electronics, also known as flex circuits, is a technology for assembling electronic circuits by mounting electronic devices on flexible plastic substrates, such as polyimide, PEEK or transparent conductive polyester film. Additionally, flex circuits can be screen printed silver circuits on polyester. Flexible electronic assemblies may be manufactured using identical components used for rigid printed circuit boards, allowing the board to conform to a desired shape, or to flex during its use. Manufacturing Flexible printed circuits (FPC) are made with a photolithographic technology. An alternative way of making flexible foil circuits or flexible flat cables (FFCs) is laminating very thin (0.07 mm) copper strips in between two layers of PET. These PET layers, typically 0.05 mm thick, are coated with an adhesive which is thermosetting, and will be activated during the lamination process. FPCs and FFCs have several advantages in many applications: Tightly assembled electronic packages, where electrical connections are required in 3 axes, such as cameras (static application). Electrical connections where the assembly is required to flex during its normal use, such as folding cell phones (dynamic application). Electrical connections between sub-assemblies to replace wire harnesses, which are heavier and bulkier, such as in cars, rockets and satellites. Electrical connections where board thickness or space constraints are driving factors. Advantage of FPCs Potential to replace multiple rigid boards or connectors Single-sided circuits are ideal for dynamic or high-flex applications Stacked FPCs in various configurations Disadvantages of FPCs Cost increase over rigid PCBs Increased risk of damage during handling or use More difficult assembly process Repair and rework is difficult or impossible Generally worse panel utilization resulting in increased cost Applications Flex circuits are often used as connectors in various applications where flexibility, space savings, or production constraints limit the serviceability of rigid circuit boards or hand wiring. Most flexible circuits are passive wiring structures that are used to interconnect electronic components such as integrated circuits, resistors, capacitors and the like; however, some are used only for making interconnections between other electronic assemblies either directly or by means of connectors. Consumer electronics devices make use of flexible circuits in cameras, personal entertainment devices, calculators, or exercise monitors.Flexible circuits are found in industrial and medical devices where many interconnections are required in a compact package. Cellular telephones are another widespread example of flexible circuits. Input Devices A common application of flex circuits is in Input devices like computer keyboards; most keyboards