Display device with projection structures on a bank
The purpose of the present invention is to precisely determine an area of the evaporated organic EL material in an organic EL display device, where organic EL layers in individual pixels emit light of different wave lengths. The purpose is realized by a structure that: A display device comprising: pixel electrodes are formed in a matrix arrangement on a substrate and a space exists between the pixel electrodes, a bank, which covers an edge of the pixel electrode, having an opening that exposes a part of one of the pixel electrodes, a first projection formed on a top of the bank and along a side of the opening, a second projection formed in an area that is near to the center of the top of the bank than the first projection is, in a plan view.
1. A display device comprising:
pixel electrodes are formed in a matrix arrangement on a substrate and a space exists between the pixel electrodes,
a bank, which covers an edge of the pixel electrodes, having an opening that exposes a part of one of the pixel electrodes,
a first projection formed on a top of the bank and along a side of the opening,
a second projection formed in an area that is near to the center of the top of the bank than the first projection is, in a plan view.
2. The display device according to claim 1 ,
wherein a second distance between a top of the second projection and a surface of the substrate is bigger than a first distance between the top of the first projection and the surface of the substrate.
3. The display device according to claim 1 ,
wherein the second projection is set between adjacently located two first projections.
4. The display device according to claim 1 ,
a first organic layer, which emits light of a first wave length, on one of the pixel electrodes,
a second organic layer, which emits light of a second wave length, on another of the pixel electrodes,
the one of the pixel electrode and the another of the pixel electrode are adjacently located,
wherein two first projections are formed between the one of the pixel electrodes and the another of the pixel electrodes.
5. The display device according to claim 4 ,
wherein the second projection is set between the two first projections.
6. The display device according to claim 1 ,
wherein the first projection surrounds the opening.
7. The display device according to claim 1 ,
wherein a length of a side of the first projection along the side of the opening is longer than a length of the side of the opening.
8. The display device according to claim 1 ,
wherein organic EL layers are formed on the pixel electrodes,
an upper electrode is formed on the organic EL layers,
the upper electrode covers the first projection and the second projection.
9. The display device according to claim 8 ,
wherein the first projection and the second projection are covered by a protective layer.
10. A display device comprising:
pixel electrodes are formed in a matrix arrangement on a substrate and a space exists between the pixel electrodes,
a bank, which covers an edge of the pixel electrodes, having an opening that exposes a part of one of the pixel electrodes,
first projections formed on a top of the bank and along a side of the opening,
wherein two first projections are formed between one of the pixel electrodes and an adjacently located another of the pixel electrodes.
11. The display device according to claim 10 ,
wherein the first projections surround the opening.
12. The display device according to claim 10 ,
wherein a length of a side of one of the first projections along the side of the opening is longer than a length of the side of the opening.
13. The display device according to claim 10 ,
wherein a second projection is set between the two first projections.
14. The display device according to claim 13 ,
wherein a second distance between a top of the second projection and a surface of the substrate is bigger than a first distance between the top of one of the first projections and the surface of the substrate.
15. The display device according to claim 13 ,
wherein organic EL layers are formed on the pixel electrodes,
an upper electrode is formed on the organic EL layers,
the upper electrode covers the first projections and the second projection.
16. The display device according to claim 15 ,
wherein the first projections and the second projection are covered by a protective layer.