Editing Flexible electronics (section)

==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 device|Input devices]] like computer keyboards; most keyboards use flex circuits for the [[Keyboard technology#Keyboard switch matrix|switch matrix]]. 

=== Displays===

==== LCD displays ====
In [[Liquid crystal display|LCD]] fabrication, glass is used as a substrate. If thin flexible plastic or metal foil is used as the substrate instead, the entire system can be flexible, as the film deposited on top of the substrate is usually very thin, on the order of a few micrometres.

==== OLED displays ====
[[Organic light-emitting diode]]s (OLEDs) are normally used instead of a back-light for flexible displays, making a [[flexible organic light-emitting diode]] display.

=== Flexible batteries===
[[Flexible battery|Flexible batteries]] are batteries, both primary and secondary, that are designed to be conformal and flexible, unlike traditional rigid ones.

=== Automotive circuits ===
In the automotive field, flexible circuits are used in instrument panels, under-hood controls, circuits to be concealed within the headliner of the cabin, and in ABS systems. 

=== Printers ===
In computer peripherals flexible circuits are used on the moving print head of printers, and to connect signals to the moving arm carrying the read/write heads of disk drives.

=== Solar cells ===
{{Main|Thin-film solar cell}}
Flexible, thin-film [[solar cell]]s have been developed for powering [[satellite]]s. These cells are lightweight, can be rolled up for launch, and are easily deployable, making them a good match for the application. They can also be sewn into backpacks or outerwear,<ref>See for instance the [[Scottevest]] solar jacket and the Voltaic [http://www.voltaicsystems.com/offgrid.shtml] {{Webarchive|url=https://web.archive.org/web/20140115021756/http://www.voltaicsystems.com/offgrid.shtml|date=2014-01-15}} and similar solar backpacks.</ref> among many other types of consumer-oriented applications. 

The growing markets related with flexible and/or portable electronics, such as for self-powered [[Internet of things|IoT systems]], have driven the development of bendable [[Thin-film solar cell|thin-film photovoltaics]] (PV) in view of enhancing the energetic autonomy of such off-grid devices.<ref>{{Cite journal |last1=Vicente |first1=António T. |last2=Araújo |first2=Andreia |last3=Mendes |first3=Manuel J. |last4=Nunes |first4=Daniela |last5=Oliveira |first5=Maria J. |last6=Sanchez-Sobrado |first6=Olalla |last7=Ferreira |first7=Marta P. |last8=Águas |first8=Hugo |last9=Fortunato |first9=Elvira |last10=Martins |first10=Rodrigo |date=2018-03-29 |title=Multifunctional cellulose-paper for light harvesting and smart sensing applications |url=https://pubs.rsc.org/en/content/articlelanding/2018/tc/c7tc05271e |journal=Journal of Materials Chemistry C |language=en |volume=6 |issue=13 |pages=3143–3181 |doi=10.1039/C7TC05271E |issn=2050-7534|url-access=subscription }}</ref> It has been shown that this class of PV technologies is already capable of reaching high solar-to-electricity efficiencies, at the level of rigid wafer-based solar cells, particularly when integrated with effective light-trapping structures. Such photonic schemes allow high broadband absorption in the thin PV absorber materials, despite their reduced thickness required for mechanical bendability.<ref>{{Cite journal |last=Haque |first=Sirazul |date=2022 |title=Photonic-Structured Perovskite Solar Cells: Detailed Optoelectronic Analysis |url=https://pubs.acs.org/doi/10.1021/acsphotonics.2c00446 |journal=ACS Photonics |volume=9 |issue=7 |pages=2408–2421 |doi=10.1021/acsphotonics.2c00446 |s2cid=250013073 |via=ACS|url-access=subscription |hdl=10773/35989 |hdl-access=free }}</ref><ref>{{Cite journal |last1=Boane |first1=Jenny L. N. |last2=Centeno |first2=Pedro |last3=Mouquinho |first3=Ana |last4=Alexandre |first4=Miguel |last5=Calmeiro |first5=Tomás |last6=Fortunato |first6=Elvira |last7=Martins |first7=Rodrigo |last8=Mendes |first8=Manuel J. |last9=Águas |first9=Hugo |date=2021 |title=Soft-Microstructured Transparent Electrodes for Photonic-Enhanced Flexible Solar Cells |journal=Micro |language=en |volume=1 |issue=2 |pages=215–227 |doi=10.3390/micro1020016 |issn=2673-8023|doi-access=free |hdl=10362/135394 |hdl-access=free }}</ref>

=== Skin-like circuits ===
In December 2021, engineers from [[Keio University]] in Tokyo and [[Stanford University]] announced the creation of stretchable and skin-like semiconductor circuits. In the future, these wearable electronics may be used to send health data to doctors wirelessly.<ref>{{cite news |last=Fox |first=Dan |url=https://www.nature.com/articles/d41586-021-03757-z |title=Stretchy electronics go wireless for flexible wearables |work=[[Nature (journal)|Nature]] |date=2021-12-14 |accessdate=2021-12-18 }}</ref>

=== Printed Electronics ===
[[Printed electronics]] are in use or under consideration include wireless sensors in packaging, skin patches that communicate with the internet, and buildings that detect leaks to enable [[Maintenance (technical)#Preventive maintenance|preventative maintenance]]. Most of these applications are still in the prototyping and development stages.<ref>{{cite web |title=Custom Printed Electronics |url=https://www.almax-rp.com/printed-electronics/ |website=Almax - RP |date=30 December 2016 |access-date=13 August 2021}}</ref> There is a particularly growing interest for flexible smart electronic systems, including photovoltaic, sensing and processing devices, driven by the desire to extend and integrate the latest advances in (opto-)electronic technologies into a broad range of low-cost (even disposable) consumer products of our everyday life, and as tools to bring together the digital and physical worlds.<ref>{{Cite journal |last1=Vicente |first1=António T. |last2=Araújo |first2=Andreia |last3=Mendes |first3=Manuel J. |last4=Nunes |first4=Daniela |last5=Oliveira |first5=Maria J. |last6=Sanchez-Sobrado |first6=Olalla |last7=Ferreira |first7=Marta P. |last8=Águas |first8=Hugo |last9=Fortunato |first9=Elvira |last10=Martins |first10=Rodrigo |date=2018-03-29 |title=Multifunctional cellulose-paper for light harvesting and smart sensing applications |url=https://pubs.rsc.org/en/content/articlelanding/2018/tc/c7tc05271e |journal=Journal of Materials Chemistry C |language=en |volume=6 |issue=13 |pages=3143–3181 |doi=10.1039/C7TC05271E |issn=2050-7534|url-access=subscription }}</ref>

Norwegian company [[Thin Film Electronics ASA|ThinFilm]] demonstrated roll-to-roll printed organic memory in 2009.<ref>[http://www.printedelectronicsworld.com/articles/winners_of_the_idtechex_printed_electronics_europe_awards_00001368.asp Thinfilm and InkTec awarded IDTechEx' Technical Development Manufacturing Award] IDTechEx, April 15th 2009</ref><ref>[http://www.eetimes.com/electronics-news/4084606/PolyIC-ThinFilm-announce-pilot-of-volume-printed-plastic-memories PolyIC, ThinFilm announce pilot of volume printed plastic memories] EETimes, September 22nd 2009</ref><ref>[http://www.printedelectronicsworld.com/articles/all_set_for_high_volume_production_of_printed_memories_00002179.asp All set for high-volume production of printed memories] Printed Electronics World, April 12th 2010</ref><ref>[http://www.printedelectronicsnow.com/articles/2010/05/thin-film-electronics-plans-to-provide-memory-ever Thin Film Electronics Plans to Provide ‘Memory Everywhere’] Printed Electronics Now, May 2010</ref>

Another company, Rotimpres based in Spain, has successfully introduced applications on different markets as for instance; heaters for smart furniture or to prevent mist and capacitive switch for keyboards on white goods and industrial machines.<ref>[https://printedelectronics.rotimpres.com/en/heaters-for-industry/ Revolutionize Your Industrial Heating with Rotimpres] Heater, October 14th 2024</ref><ref>[https://printedelectronics.rotimpres.com/en/applications/capacitive-keyboards/ Capacitive keyboards - Rotimpres] Capacitive switch, October 14th 2024</ref>