Light emitting device and manufacturing method thereof and display used this light emitting device
A light emitting device and a manufacturing method thereof and a display used the light emitting device, in which fine patterning for the light emitting device is realized by a simple process and the light leakage is prevented and the efficiency at extracting light is increased, are provided. The light emitting device provides an organic electroluminescent (EL) device in which electrodes and a luminescent layer are formed, a diffraction grating or a zone plate, and a filter. Light emitted from the luminescent layer transmits through the diffraction grating or the zone plate, which is formed with a designated grating pitch, or is reflected at the diffraction grating or the zone plate. With this, the transmitting or reflecting light is controlled to be in a designated angle region. And when the light is transmitted through the filter, light having different color tone and chromaticity from those of the light emitted from the luminescent layer is extracted.
1. A light emitting device, comprising:
an organic electroluminescent (EL) device having one or more organic thin film layers including a luminescent layer between an anode and a cathode;
a diffraction grating or a zone plate disposed in said organic EL device or adjacent to said organic EL device; and
a filter disposed on the outside of said organic EL device and said diffraction grating or said zone plate, and disposed parallel to the organic thin film layers wherein:
light emitted from said luminescent layer is transmitted through an electrode, comes out on the side opposite to said luminescent layer and passes through said filter, and light whose color tone and chromaticity are different from those of said light emitted from said luminescent layer is extracted.
2. A light emitting device in accordance with claim 1 , wherein:
in said anode and said cathode of said organic EL device which composes a pixel, one of said electrodes is transparent at the visible light region and light is extracted through this electrode, and
the other electrode reflects visible light, and
said diffraction grating or said zone plate is formed on said electrode that reflects visible light.
3. A light emitting device in accordance with claim 1 , wherein:
in said anode and said cathode of said organic EL device which composes a pixel, one of said electrodes is transparent at the visible light region and light is extracted through this electrode, and
the other electrode reflects visible light, and
said diffraction grating or said zone plate is formed on said electrode being transparent.
4. A light emitting device in accordance with claim 3 , wherein:
said diffraction grating or said zone plate has a light transmitting property.
5. A light emitting device in accordance with claim 1 , wherein:
said diffraction grating or said zone plate has a two-dimensional cycle.
6. A light emitting device in accordance with claim 1 , wherein:
on one surface of a substrate having a light transmitting property, said electrodes, said one or more organic EL layers, and said diffraction grating or said zone plate are formed, and
on the other surface of said substrate having said light transmitting property, said filter is disposed.
7. A light emitting device in accordance with claim 1 , wherein:
on a surface of a substrate, said electrodes, said one or more organic EL layers, and said diffraction grating or said zone plate are formed, and
on the side being the same side of said substrate, where said electrodes, said one or more organic EL layers, and said diffraction grating or said zone plate are formed, said filter is disposed so that said filter does not directly contact said electrodes, said one or more organic EL layers, and said diffraction grating or said zone plate.
8. A light emitting device in accordance with claim 1 , wherein:
said filter contains a fluorescent material or a phosphorescence material, which absorbs light emitted from said luminescent layer and emits light whose wavelength is different from that of said light emitted from said luminescent layer.
9. A light emitting device in accordance with claim 1 , wherein:
on a light emitting surface of said filter, said filter has a light scattering function.
10. A display, comprising:
arrayed plural light emitting devices as claimed in claims 1 , 2 , 5 , 7 , 8 , and 9 .
11. A display, comprising:
arrayed plural light emitting devices as claimed in claims 1 , 3 , 4 , 5 , 6 , 8 , and 9 .
12. A light emitting device in accordance with claim 1 , wherein:
one of the electrodes and either said diffraction grating or said zone plate are disposed on a substrate,
said organic thin film layers are disposed on either said diffraction grating or said zone plate,
a transparent electrode is disposed on said organic thin film layers, and
said filter are disposed on said transparent electrode.
13. A light emitting device in accordance with claim 12 , wherein:
said filter contains a fluorescent material or a phosphorescence material, which absorbs light emitted from said luminescent layer and emits light whose wavelength is different from that of said light emitted from said luminescent layer.