LEDFilm
Encyclopedia
The LED Film, also called LED embedded film or LED lighting film is a thin and flexible electronic circuit with surface mounted light emitting diodes on the polymeric film. One type of conductive material may consist of transparent conductive films,:

Gallery

Because industrial IPC-T-50 "Terms and Definitions for Printed Boards" are defining a flexible circuit
Flexible circuit
The industry standard IPC-T-50 "Terms and Definitions for Printed Boards" defines a flexible circuit as:"A patterned arrangement of printed wiring utilizing flexible base material with or without flexible cover layers."...

 as "A patterned arrangement of printed wiring utilizing flexible base material with or without flexible cover layers.", this definition cannot be applied to the transparent type of flexible circuits, which will contain no printed wiring, in fact no wiring at all.

Basematerials for non transparent LED Films are usually based on thermally stable materials, like PEN
Polyethylene naphthalate
Polyethylene naphthalate Polyethylene naphthalate (PEN) Polyethylene naphthalate (PEN) (Poly(ethylene 2,6-naphthalate) is a polyester with good barrier properties (even better than Polyethylene terephthalate). Because it provides a very good oxygen barrier, it is particularly well-suited for...

 or Polyimide
Polyimide
Polyimide is a polymer of imide monomers. The structure of imide is as shown. Polyimides have been in mass production since 1955...

 to enable reflow soldering pastes
Reflow soldering
Reflow soldering is a process in which a solder paste is used to temporarily attach one or several electrical components to their contact pads, after which the entire assembly is subjected to controlled heat, which melts the solder, permanently connecting the joint...

 to sinter
Sintering
Sintering is a method used to create objects from powders. It is based on atomic diffusion. Diffusion occurs in any material above absolute zero, but it occurs much faster at higher temperatures. In most sintering processes, the powdered material is held in a mold and then heated to a temperature...

 at temperatures exceeding 220 °C. In the case of Polyimide and PEN the conductive paths will be printed
Printed circuit board
A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate. It is also referred to as printed wiring board or etched wiring...

 to the base materials mentioned above.

To enable transparent conductivity, the other solution consist of laser patterning
Laser engraving
Laser engraving, or laser marking, is the practice of using lasers to engrave or mark an object. The technique does not involve the use of inks, nor does it involve tool bits which contact the engraving surface and wear out...

 transparent conducive material, which was vacuum sputtered
Sputtering
Sputtering is a process whereby atoms are ejected from a solid target material due to bombardment of the target by energetic particles. It is commonly used for thin-film deposition, etching and analytical techniques .-Physics of sputtering:...

 on the base material, for example on highly transparent Polyester
Polyester
Polyester is a category of polymers which contain the ester functional group in their main chain. Although there are many polyesters, the term "polyester" as a specific material most commonly refers to polyethylene terephthalate...

. Polyester may not be sintered, in fact it will lose its flatness at temperatures exceeding 80 °C. Consequently the pick & place process
SMT Placement Equipment
SMT component placement systems, commonly called pick-and-place machines or P&Ps, are robotic machines which are used to place surface-mount devices onto a printed circuit board...

 must be done at low temperatures using appropriate heat free curing pastes. These paste may consist of metall powders filled lacquers, which will dry for example. Or they may consist of metall powders filled 2 component glues, like epoxy resins.

Transparent conductive LEDFilms are used for standard LED glass
Ledglass
Ledglass is a building material which contains some functional electronics, light-emitting diodes. The LEDGlass and its technology is described in different articles, It allows for example glass facades to be used as marketing area or windshield glasses to be used as display...

 , transparent LED glass
Transparent LED embedded Glass
Transparent LED-embedded glass is a new composite material containing light-emitting diodes . It is used as building material and as glass type for many different products. This new technology enables materials, new applications in electronics and architecture...

, for automotive LED composites
LED Headliner
The Dictionary of Automotive Terms defines headliners "as fabric or vinyl upholstery on the interior of the roof of a vehicle". Wikipedia's definition is a bit more informative: "A headliner is a composite material that consists of a face fabric with nonwoven or foam backing that is adhered to the...

, or for laminated films between other materials like PVC, metals, polymers, stones, or natural materials like wood.
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