Patent Application
20100133434
(a) Field of the Invention
The present invention relates to an organic semiconductor infrared distance sensing apparatus and an organic infrared emitting apparatus thereof, and more particularly to a technical field of using completely organic materials as active layer devices which comprise light-emitting and detecting apparatuses, and sensing the distance between the obstacle and the apparatus by infrared light.
(b) Description of the Prior Art
In general, most polymers are insulators because their long hydrocarbon chains with covalent single bonds have no freely movable charges. However, conjugated conductive polymers are intrinsically conductive. Unlike conventional polymer composites doped with metal powders or conductive carbon blacks, conjugated conductive polymers are principally characterized in that the main chains of the polymers are composed of alternate conjugated single and double bonds and they have the ability to transport electrons and holes. Such polymers are totally referred to as conductive polymers. If electrons and holes can recombine with each other in organic polymers to emit photons, the polymers are referred to as organic light-emitting polymers. They can be made into organic light-emitting diodes and can be used in simple solution processes, such as spin coating, etc. This simplifies the problems of current complicant fabrication processes and expensive facilities for inorganic semiconductors.
Although organic semiconductors have the foregoing advantages and the like, their energy gaps mostly fall within the visible light range due to their energy band structures. Therefore, it is really hard to manufacture them into organic infrared emitting diodes or organic infrared receiving apparatuses. The present invention utilizes energy transfer to emit infrared light and utilizes an organic infrared receiver to receive the infrared light so as to determine the distance. This invention has never been disclosed in public before this patent application was filed.
To solve all the problems of the prior art, the inventors propose an organic semiconductor infrared distance sensing apparatus and an organic infrared emitting apparatus thereof based on their research and development for many years and plenty of practical experience, thereby improving the above defects.
In view of the above-mentioned circumstances, an objective of the present invention is to provide an organic semiconductor infrared distance sensing apparatus for sensing an obstacle. The infrared distance sensing apparatus comprises an organic infrared emitting apparatus and an organic infrared receiving apparatus. The organic infrared emitting apparatus comprises an organic light-emitting diode and an infrared organic conversion layer. The infrared organic conversion layer comprises infrared dye molecules, and the infrared organic conversion layer absorbs and transfers the light emitted by the organic light-emitting diode to the infrared dye molecules to emit infrared light. The organic infrared receiving apparatus receives the infrared light reflected by an obstacle and generates an electrical signal corresponding to the infrared light. The electrical signal is associated with the distance between the obstacle and the infrared distance sensing apparatus.
Furthermore, another objective of the present invention is to provide an organic infrared emitting apparatus, which comprises an electrode layer having a positive electrode layer and a negative electrode layer to form an electric field and corresponding to each other; a light-emitting layer is located between the positive electrode layer and the negative electrode layer; and an infrared organic conversion layer is located at one side of the electrode layer, comprising energy conversion agent molecules and infrared dye molecules.
When the electrode layer is operated under a positive bias, a plurality of electrons and holes are respectively injected from the electrode layer into the light-emitting layer and recombine with each other in the light-emitting layer to emit photons. The infrared organic conversion layer absorbs and transfers the energy of the photons to the infrared emitting molecules to emit infrared light.
Referring to
Moreover, in another embodiment, there is another fabrication method for the infrared organic conversion layer 12. The infrared dye molecules 122 directly absorb the energy of the visible light emitted by the organic light-emitting diode such that the energy can be directly transferred to the infrared dye molecules 122. Due to the poor film-forming ability of the infrared dye molecules, an assistant film-forming host 124, such as PVP is used to assist in forming a film so as to form the infrared organic conversion layer 12, as shown in
The structure of an organic infrared sensing apparatus according to the present invention is similar to the above organic light-emitting diode. An active layer film is sandwiched between a cathode and an anode. This active layer film comprises two materials: one is an electron-donating material, P3HT, and the other is an electron-accepting material, PCBM. These two materials are mixed in equal proportions in the active layer film. When the infrared light is reflected into the active layer film, it is absorbed by the active layer film to generate excitons, i.e. electron and hole pairs. The excitons will be dissociated into electron carriers and hole carriers when they reaches the interface between P3HT and PCBM. This is because both electrons and holes would move toward lower energy levels. The HOMO energy of P3HT is lower relative to a hole; the LUMO energy of PCBM is lower relative to an electron. As a result, dissociated holes are conducted through P3HT and collected by the anode; electrons are conducted through PCBM and collected by the cathode. The current collected in a formed loop is photocurrent.
Referring to
As mentioned above, the organic semiconductor infrared distance sensing apparatus according to the present invention has the following advantages:
(1) Completely organic materials are employed in the active layer of the organic infrared distance sensing apparatus. Thus, its process is simple, convenient and inexpensive, as well as it is suitable for use in a large area process and has flexibility.
(2) Light energy of a wavelength of a conventional visible light source can be absorbed by the organic infrared emitting apparatus whereby the convenience of the organic infrared emitting apparatus can be enhanced.
(3) Conventional dye molecules can be used as the absorbent material in the organic infrared emitting apparatus, thereby capable of improving the application of an organic semiconductor light-emitting apparatus to the control of color changing.
The above description is illustrative only and is not to be considered limiting. Various modifications or changes can be made without departing from the spirit and scope of the invention. All such equivalent modifications and changes shall be comprised within the scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 097146426 | Nov 2008 | TW | national |
