Patent Application
20070247054
A more complete appreciation of the present invention, and many of the attendant features thereof, will be readily apparent as the present invention becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings, in which like reference symbols refer to like components, wherein:
Exemplary embodiments of the present invention will now be described more fully with reference to the accompanying drawings.
Referring to
The sealing member 14 can be formed of a frit bar prepared by press-forming a mixture of a glass frit and an organic compound. Alternatively, the sealing member 14 can be formed of a glass bar and an adhesive layer disposed on upper and lower surfaces of the glass bar. The first and second substrates 10 and 12 are attached to each other while the frit bar or the adhesive layer is molten in the firing process.
In this embodiment, the first and second substrates 10 and 12 are respectively provided with non-facing portions 101 and 121 on which electrode pads will be arranged. The non-facing portions 101 and 121 do not overlap with the other substrates in a thickness direction (a direction of a z-axis in
For example, as shown in
When the first and second substrates 10 and 12 are aligned with each other such that they have the non-facing portions 101 and 121, respectively, the fixing members 16 are arranged on the non-facing portion 101 (or 121) of one of the first and second substrates 10 and 12 to securely contact the side surface of the other of the first and second substrates 10 and 12, thereby preventing the first and second substrates 10 and 12 from rotating relative to each other.
The fixing members 16 are fixed on one of the first and second substrates 10 and 12 (the first substrate 10 in
The fixing members 16 can be uniformly distributed along the peripheries of the facing portions. In this case, when a force rotating the first and second substrates 10 and 12 relative to each other is applied during the manufacturing process, the fixing member 16 uniformly supports the side surfaces of the second substrate 12, thereby preventing the first and second substrates 10 and 12 from rotating relative to each other.
For example, the fixing members 16 can be formed at outer portions of four corners of the facing portion of the first substrate 10. That is, four fixing members 16 are respectively formed at outer portions of the respective four corners of the facing portion such that the four fixing members 16 contact both longitudinal side surfaces of the second substrate 12. That is, the four fixing members 16 are fixed on the non-facing portion formed at the longitudinal side edges of the first substrate 10.
The fixing members 16 can be formed having a rectangular section. However, the present invention is not limited to this case. That is, the number and location of the fixing members are not limited to the described embodiment.
The adhesive layers 18 for attaching the fixing members 16 on the substrate are formed of a material having a softening point higher than that of the frit bar or the adhesive layer forming the sealing member 14 so that the fixing members 16 can keep their initial positions during the firing process for attaching the first and second substrates 10 and 12 to each other.
According to this embodiment, since the fixing members are formed on the non-facing portion of one of the first and second substrates, the rotation of the first and second substrates relative to each other can be prevented, thereby accurately maintaining the aligned state of the first and second substrates.
Referring first to
Referring to
Then, the resulting assembly is loaded in a firing furnace so that the first and second substrates 10 and 12 can be attached to each other by melting a surface of the frit bar or the adhesive layer.
At this point, when the first and second substrates 10 and 12 tend to slip or rotate relative to each other due to the thermal deformation thereof, the fixing members 16 suppress the relative rotation between the first and second substrates 10 and 12. Therefore, the first and second substrates 10 and 12 maintain their aligned state, which is set before the resulting assembly is loaded in the firing furnace, thereby obtaining the good alignment.
Next, referring to
As shown in
The electron emission elements can be FEA elements, SCE elements, MIM elements, MIS elements, or any other suitable electron emission elements known to those skilled in the art.
Referring to
When the crossed regions of the cathode electrodes 26 and the gate electrodes 28 define pixel regions, openings 241 and 281 corresponding to the respective electron emission regions 30 are formed through the first insulating layer 24 and the gate electrodes 28 to expose the electron emission regions 30 on the first substrate 10′.
The electron emission regions 30 are formed of a material emitting electrons when an electric field is applied thereto under a vacuum atmosphere, such as a carbonaceous material or a nanometer-size material. The electron emission regions 30 can be formed of carbon nanotubes, graphite, graphite nanofibers, diamonds, diamond-like carbon, C60, silicon nanowires, or a combination thereof.
Alternatively, the electron emission regions can be tips formed of a Mo-based or Si-based material.
Returning now to
The light emission unit 201′ includes phosphor layers 36 such as red (R), green (G) and blue (B) phosphor layers 36R, 36G and 36B and black layers 38 arranged between the R, G and B phosphor layers 36R, 36G and 36B to enhance the contrast of the screen. Each crossed region of the cathode electrodes 26 and the gate electrodes 28 corresponds to a single-color phosphor layer.
An anode electrode 40 formed of a metallic material such as aluminum is formed on the phosphor layers 36 and the black layers 38. The anode electrode 40 receives a high voltage required for accelerating the electron beams, and reflects the visible light rays radiated from the phosphor layers 36 toward the first substrate 10′ to the second substrate 12′, thereby increasing the screen luminance.
The anode electrode can be formed of a transparent conductive material such as indium tin oxide (ITO). In this case, the anode electrode is placed on a surface of the phosphor layers 36 and the black layers 38 facing the second substrate 12′. Furthermore, the anode electrode can be formed of a double-layered structure having a transparent conductive material-based layer and a metallic material-based layer.
As shown in
The electron emission display of this embodiment is driven by supplying driving voltages to the cathode, gate, focusing and anode electrodes 26, 28, 34, and 40.
For example, one of the cathode and gate electrodes 26 and 28 receives a scan driving voltage to function as a scan electrode while the other receives a data driving voltage to function as a data electrode. The focusing electrode 34 receives OV or a negative direct current voltage of several to tens of volts, and the anode electrode 40 receives a positive direct current voltage of hundreds or thousands of volts.
Then, electric fields are formed around the electron emission regions 30 due to the voltage difference between the cathode electrode 26 and the gate electrode 28, and electrons are emitted from the electron emission regions 30. The emitted electrons are focused to the center of the bundle of electron beams while passing the openings 341 of the focusing electrode 34, and attracted by the high voltage supplied to the anode electrode 40, thereby colliding against the phosphor layers 36 at the relevant pixels and causing them to emit light.
In an electron emission display of this embodiment, an electron emission unit 200″ includes first and second electrodes 44 and 46 arranged on a first substrate 10″ in parallel with each other and spaced apart by a predetermined distance, and first and second conductive thin films 48 and 50 placed close to each other while partially covering the surface of the first and the second electrodes 44 and 46, and electron emission regions 52 disposed between the first and the second conductive thin films 48 and 50.
The first and the second electrodes 44 and 46 can be formed of various conductive materials. The first and the second conductive thin films 48 and 50 can be formed of micro particles based on a conductive material, such as nickel, gold, platinum, and palladium.
The electron emission regions 52 can be formed of high resistance cracked portions provided between the first and the second conductive thin films 48 and 50, or can contain carbon and/or one or more carbon compounds. In the case of the latter, the electron emission regions 52 can be formed of carbon nanotubes, graphite, graphite nanofibers, diamonds, diamond-like carbon, C60, silicon nanowires or a combination thereof.
A light emission unit 201″ is spaced apart from the electron emission unit 200″ at a predetermined distance by spacers 42′. Since the light emission unit 201″ is identical to the light emission unit 201′ of the electron emission display of
With the above-described structure, when predetermined driving voltages are supplied to the first and the second electrodes 44 and 46, an electric current flows through the first and the second conductive thin films 48 and 50 in a horizontal direction of the surface of the electron emission regions 52, thereby causing a surface conduction electron emission. The emitted electrons are attracted by the high voltage supplied to the anode electrode 40, and migrated toward the second substrate 12″, thereby colliding against the phosphor layers 36 at the relevant pixels and causing them to emit light.
With the above-structured electron emission display device, an electron emission unit is formed at the active area of the first substrate 10″, and a light emission unit is formed at the active area of the second substrate 12″. The first and the second substrates 10″ and 12″ are sealed together using a sealing member with support frames, adhesive layers and fillers, and the interior thereof is exhausted.
As the electron emission displays described in the foregoing embodiments have the vacuum envelope, the relative rotation between the first and second substrates 10 (or 10′ or 10″) and 12 (or 12′ or 12″) can be effectively prevented. Therefore, the electron emission unit formed on the first substrate 10 (or 10′ or 10″) can maintain an accurate alignment with the phosphor layers 36, thereby realizing a high quality image.
Although exemplary embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that many variations and/or modifications of the basic inventive concept taught herein still fall within the spirit and scope of the present invention, as defined by the appended claims and equivalents thereof.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2006-0035832 | Apr 2006 | KR | national |
