Electric lamp and discharge devices – With luminescent solid or liquid material – Solid-state type
Reexamination Certificate
1999-12-22
2003-05-20
Patel, Vip (Department: 2879)
Electric lamp and discharge devices
With luminescent solid or liquid material
Solid-state type
C313S506000, C313S504000
Reexamination Certificate
active
06566808
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to lighting applications, and more particularly to a display device comprising an organic light emitting material.
2. Description of the Related Art
There has been a longstanding desire to make inexpensive signs that can be read in the dark. A conventional approach is to utilize a glass or plastic plate with one or more color filters positioned such that the desired sign is created when placed over a backlight. An example of this is the common “EXIT” sign. This technology, however, is not easily customizable, because the end user is not able to easily design and create such a sign. Most end users do not have the necessary tools or expertise to make the filter plate themselves. Instead, the end user must obtain the services of a filter plate manufacturer to create a customized sign. Most end users do not follow through with such an endeavor.
Many technologies have been developed to allow more customizable signs that can be read in the dark. Most of these are variations on a cathode ray tube (CRT) display. Such displays can be quickly reconfigured electronically to display a new sign. Other technologies with the same capability include liquid crystal displays, thin-film plasma displays, and organic electroluminescent displays. However, these displays require complicated electronics and are too expensive for many simple display sign applications.
Consequently, there is a longstanding need for a simple, inexpensive illuminated sign which can be easily customized by an end user.
BRIEF SUMMARY OF THE INVENTION
The invention relates to a luminescent display comprising a first electrode, a second electrode, an organic light emitting layer disposed between the first and second electrodes, and a luminescent material which receives light from the organic light emitting layer and converts the light to a different wavelength, wherein the first and second electrodes together define an overlap region in which the organic light emitting layer is activated to emit light, and the luminescent material is disposed in a portion of the overlap region.
The invention also relates to a phosphor in solution, a light emitting device comprising a first electrode, a second electrode, and an organic light emitting layer, and means for applying the phosphor onto the light emitting device. The means for applying may comprise a printer cartridge containing at least one phosphor, for example. The printer cartridge may be used to print the luminescent material onto the light emitting device. The means for applying may also comprise a manual implement such as paint brush, a stamp, or a pen. The phosphor solution can be painted, stamped, or written on the light emitting device in any desired pattern and color.
The invention also relates to a method comprising the steps of creating an image and printing the image on a light emitting device comprising an organic light emitting layer after the light emitting device has been formed. The image may be created, for example on a personal computer, and printed with an inkjet printer. The image may be printed in phosphors which emit light of one wavelength upon absorbing light of a different wavelength from the organic light emitting layer.
Various embodiments of the invention allow customized luminescent displays to be easily fabricated by end users by applying a phosphor pattern to a preformed, encapsulated light emitting device. The light emitting device typically comprises an organic light emitting layer which provides illumination over a large surface area. The phosphor pattern can be applied to the light emitting device in a number of ways available to end users, such as with a computer printer or a manual implement. The availability of computer generated images allows end users to create professional quality luminescent displays with minimal investment in equipment.
REFERENCES:
patent: 3558886 (1971-01-01), Carver
patent: 4186020 (1980-01-01), Wachtel
patent: 4539507 (1985-09-01), VanSlyke et al.
patent: 4769292 (1988-09-01), Tang et al.
patent: 5247190 (1993-09-01), Friend et al.
patent: 5294870 (1994-03-01), Tang et al.
patent: 5708130 (1998-01-01), Woo et al.
patent: 5772741 (1998-06-01), Spinelli
patent: 5874803 (1999-02-01), Garbuzov et al.
patent: 5874804 (1999-02-01), Rogers
patent: 5952778 (1999-09-01), Haskal et al.
patent: 5997622 (1999-12-01), Weber et al.
patent: 5998925 (1999-12-01), Shimizu et al.
patent: 6162490 (2000-12-01), Graves et al.
patent: 6166489 (2000-12-01), Thompson et al.
patent: 0969699 (2000-01-01), None
Florian Pschenitzka et al.,Three-Color Organic Light-Emitting Diodes Patterned by Masked Dye Diffusion, 74 Appl. Phys. Lett. 1913-1915 (Mar. 29, 1999).
Jayesh Bharathan et al.,Polymer Electroluminescent Devices Processed by Inkjet Printing: I. Polymer Light-Emitting Logo, 72 Appl. Phys. Lett. 2660-2662 (May 25, 1998).
Hiroyuki Suzuki et al.,Near-Ultraviolet Electroluminescence from Polysilanes, 331 Thin Solid Films, 64-70, (1998) no month.
Chung-Chih Wu et al.,Efficient Organic Electroluminescent Devices Using Single-Layer Doped Polymer Thin Films with Bipolar Carrier Transport Abilities, 44 EE Transactions on Electron Devices, 1269-1281 (Aug. 1997).
Junji Kido,Organic Displays, Physics World, 27-30 (Mar. 1999).
G. Gustafsson et al.,Flexible Light-Emitting Diodes Made from Soluble Conducting Polymers, 357 Nature, 477-479 (Jun. 11, 1992).
Junji Kido et al.,Organic Electroluminescent Devices Based on Molecularly Doped Polymers, 61 Appl. Phys. Lett. 761-763 (Aug. 17, 1992).
A. W. Grice et al.,High Brightness and Efficiency Blue Light-Emitting Polymer Diodes, 73 Appl. Phys. Lett. 629-631 (Aug. 3, 1998).
Duggal Anil Raj
Srivastava Alok Mani
General Electric Company
Johnson Noreen C.
Patel Vip
Vo Toan P.
Williams Joseph
LandOfFree
Luminescent display and method of making does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Luminescent display and method of making, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Luminescent display and method of making will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3035543