Flexible touch screen display
View Patent ↗A touch sensitive active matrix display device is provided. The device includes a display fabricated on a first flexible substrate, said display having a viewing surface. The device further includes a touch sensitive sensor including a second flexible substrate, under said display. The touch sensor is operated by touching said viewing surface of said display, and said combined display and touch sensitive sensor is flexible.
1. A touch sensitive active matrix display device, the device comprising:
a display having a viewing surface; and
a touch sensitive sensor integrated with and under said display, said touch sensitive sensor comprising a flexible substrate, a lower conductive layer on said flexible substrate and an upper conductive layer separated from said lower conductive layer by a spacer arrangement; and wherein
said touch sensor is operable by touching said viewing surface of said display; and wherein:
said display comprises electronic paper display medium and has a backplane comprising an active matrix, said active matrix having an array of field-effect transistors comprising an organic semiconductor, said transistors configured to control said display;
said backplane is disposed directly onto said upper conductive layer with a dielectric isolation layer between said upper conductive layer and electroactive layers of said backplane, with said dielectric isolation layer providing electrical insulation between said upper conductive layer and said electroactive layers of said backplane; and
said display and touch sensitive sensor in combination have a flexibility greater than needed for functionality of operation of said touch sensitive sensor such that said display and touch sensitive sensor in combination is bendable as a whole.
2. A touch sensitive display device as claimed in claim 1 wherein said touch sensitive sensor includes a layer comprising a substantially non-transparent conductor.
3. A touch sensitive display device as claimed in claim 1 wherein said display includes a backplane comprising an array of thin-film transistors, and wherein said backplane is located substantially on a neutral surface of said device.
4. A touch sensitive display device as claimed in claim 1 wherein said display comprises a pixellated display.
5. A touch sensitive display device as claimed in claim 1 wherein said touch sensitive sensor comprises a mechanical sensor configured to bring said conducting layers into contact with one another to electrically connect said first and second conducting layers of conductors in response to mechanical pressure.
6. A touch sensitive display device as claimed in claim 1 wherein said display includes a multilayer electronic structure adapted to solution deposition.
7. A touch sensitive display device as claimed in claim 6 wherein said multilayer electronic structure comprises said active matrix backplane of said display.
8. A touch sensitive active matrix display device as claimed in claim 1 , wherein said organic semiconductor is a solution-processed polymer semiconductor.
9. A touch sensitive active matrix display device as claimed in claim 1 , wherein said field-effect transistor comprises an organic gate dielectric.
10. A touch sensitive active matrix display device as claimed in claim 9 , wherein said organic gate dielectric is a solution-processed polymer dielectric.
11. A touch sensitive active matrix display device as claimed in claim 9 , wherein said organic gate dielectric is deposited by chemical vapour deposition.
12. A touch sensitive active matrix display device as claimed in claim 9 , where said organic gate dielectric is parylene.
13. A touch sensitive active matrix display device as claimed in claim 9 , wherein said organic gate dielectric has a thickness between 200 nm and 1 μm.
14. A touch sensitive active matrix display device as claimed in claim 1 , wherein said touch sensitive sensor is a resistive touch sensor.
15. A touch sensitive display device as claimed in claim 1 wherein said flexible substrate has a thickness in the range of 10 μm to 250 μm.
16. A touch sensitive display device as claimed in claim 1 wherein said flexible substrate has a thickness in the range 20 μm to 200 μm.
17. A touch sensitive display device as claimed in claim 1 wherein said dielectric isolation layer has a thickness of 1-20 μm.
18. A touch sensitive display device as claimed in claim 1 wherein said dielectric isolation layer is arranged to provide planarization of the surface of said touch screen.
19. A touch sensitive display device as claimed in claim 1 wherein said backplane is laminated onto said upper conductive layer with only said dielectric isolation layer between said upper conductive layer and said electroactive layers of said backplane.