Electric lamp and discharge devices: systems – Plural power supplies – Plural cathode and/or anode load device
Reexamination Certificate
2000-02-25
2001-09-11
Philogene, Haissa (Department: 2821)
Electric lamp and discharge devices: systems
Plural power supplies
Plural cathode and/or anode load device
C345S074100, C345S076000, C313S306000
Reexamination Certificate
active
06288494
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electron-emitting device having an innovative arrangement, and to an image-forming apparatus, such as an electron source apparatus or an image-displaying apparatus, that uses such an electron-emitting device.
2. Related Background Art
Conventionally, roughly there are two types of well known electron-emitting devices: one is a thermionic cathode, and the other is a cold-cathode. A field emission type (hereinafter referred to as an “FE”), a metal/insulator-metal type (hereinafter referred to as an MIM), and a surface conduction electron-emitting type are classified into the cold cathode.
A well known FE example is disclosed in “Field Emission”, W. P. Dyke and W. W. Dolan, Advances in Electron Physics, 8.89 (1956), or in “Physical Properties of Thin-film Field Emission Cathodes With Molybdenum Cones”, C. A. Spindt, J. Applied Physics, 47, 5248 (1976).
Additional, current discussions are: “Fluctuation-free Electron Emission From Non-formed Metal-insulator-metal (MIM) Cathodes Fabricated By Low Current Anodic Oxidation”, Toshiaki Kusunoki, Jpn., J. Applied Physics, vol. 32 (1993), pp. L1695; and “An MIM-Cathode Array For Cathode Luminescent Displays”, Mutsumi Suzuki, et al., IDW '96, (1996), pp. 529.
An example surface conduction type is disclosed in a report by M. I. Elinson in Radio Engineering Electron Physics, 10 (1965). The surface conduction electron-emitting device employs a phenomenon whereby an electron emission occurs when a current is supplied in parallel to the surface of a thin film that is formed on a small area of a substrate. The surface conduction electron-emitting devices are devices that use an SnO
2
thin film (described in the Elinson report), a device that employs an Au thin film (reported by G. Dittmer, Thin Solid Films, 9, 317 (1972), and a device that employs an In
2
O
3
/SnO
2
thin film (reported by M. Hartwell and C. G. Fonstad, IEEE Trans. ED Conf., 519 (1983)).
A plane type electron-emitting device shown in
FIGS. 50A and 50B
and a step type electron-emitting device shown in
FIG. 52
are other surface conduction type devices proposed by the present inventor.
In
FIGS. 50A and 50B
, schematic diagrams illustrate a conventional surface conduction electron-emitting device. In
FIG. 50A
, a specific top plan view of an electron-emitting device is shown, and in
FIG. 50B
, a specific transverse cross-sectional view of the device is shown. In the views shown, a high-potential side electrode
1002
and a low-potential side electrode
1003
, which together constitute the electron-emitting device, are mounted on a substrate
1001
and are connected to a power source (not shown). The high-potential side electrode
1002
is connected to an electroconductive thin film
1004
, while the low-potential side electrode
1003
is connected to an electroconductive thin film
1005
. The thicknesses of the electrodes
1002
and
1003
are several tens of nm to several &mgr;m, and the thicknesses of the films
1004
and
1005
are 1 to several tens of [nm]. A gap
1006
is defined that substantially electrically discontinues the thin films
1004
and
1005
.
For these conventional surface condition electron-emitting devices, generally, before electron emission, an electron-emitting region is formed by performing a so-called “energization-forming” process for electroconductive thin film. That is, in the “energization forming” process, a direct-current voltage, or a very gradual boosting voltage, i.e., a voltage of 1 V, is applied at both ends of an electroconductive thin film to locally destroy, deform or degenerate the electroconductive thin film, so as to form an electron-emitting region wherein the electrical resistance is high.
Furthermore, when a process is performed called activation, during which, for energization, an organic gas is introduced into a vacuum, a carbon film is deposited at the distal ends of the electroconductive thin films facing each other across the gap between them, so as to form an electron-emitting region having an improved electron emission characteristic. When a voltage is applied to the electroconductive thin films and a current is supplied to the surface conduction electron-emitting device that is provided by the energization forming operation and the activation operation, electrons are emitted from the electron-emitting region.
Recently, a flat type display apparatus has become popular for which a liquid crystal, instead of a CRT, is used as an image-forming apparatus, such as a display device. However, since this display apparatus is not an emissive type, it must include a backlight, and as result, a demand exists for an emissive display apparatus. An emissive type display apparatus is, for example, an image forming apparatus that comprises: an electron source, wherein multiple surface conduction electron-emitting devices are arranged; and a phosphor, which emits visible light using electrons output by the electron source (e.g., U.S. Pat. No. 5,066,883). An example electron source wherein multiple surface conduction electron-emitting devices are arranged is one having multiple surface conduction electron-emitting devices that are arranged in parallel as multiple arrays (ladder-shaped arrays), and wherein both ends (both device electrodes) of each electron-emitting device are connected by wiring (common wiring) (e.g., Japanese Patent Application Laid-Open Nos. 64-31332, 1-283749 and 1-257552).
SUMMARY OF THE INVENTION
An electron-emitting apparatus according to the present invention comprises:
a substrate, which has a first major surface and a second major surface that are positioned opposite each other;
an electron-emitting device, which comprises a first electrode, to which a first voltage is applied, and a second electrode, to which a voltage Vf is applied, that are mounted, with an interval, on the first major surface;
an anode electrode, which is located opposite and at a distance H from the first major surface;
first voltage application means, for applying to the second electrode the voltage Vf that is higher than the first voltage; and
second voltage application means, for applying to the anode electrode a voltage Va that is higher than the voltage Vf,
wherein a space defined between the anode electrode and the electron-emitting device is maintained in a reduced-pressure condition, and
wherein, when a value Xs=H*Vf/(&pgr;*Va) is established for a plane that is substantially perpendicular to the first major surface, a width w of the second electrode, in a direction substantially parallel to the first major surface, equals or exceeds 0.5 times the value Xs and is smaller than or equals 15 times the value Xs.
An image-forming apparatus according to the present invention comprises:
a substrate having a first major surface and a second major surface that are positioned opposite each other;
an electron-emitting device, which includes a first electrode, to which a first voltage is applied, and a second electrode, to which a voltage Vf is applied, that are mounted, with an interval, on the first major surface;
a second substrate, on which an anode electrode, which is located opposite and at a distance H from the first major surface, and an image-forming member are mounted;
first voltage application means, for applying to the second electrode the voltage Vf that is higher than the first voltage; and
second voltage application means, for applying to the anode electrode a voltage Va that is higher than the voltage Vf,
wherein a space defined between the anode electrode and the electron-emitting device is maintained in a reduced-pressure condition, and
wherein, when a value Xs=H*Vf/(&pgr;*Va) is established for a plane that is substantially perpendicular to the first major surface, a width w of the second electrode in a direction substantially parallel to the first major surface equals or exceeds 0.5 times the value Xs and is smaller than or equals 15 times the value Xs.
For the electron-emitting apparatus and the image-formin
Matsutani Shigeki
Sasaguri Daisuke
Tsukamoto Takeo
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
Philogene Haissa
Tran Thuy Vinh
LandOfFree
Electron-emitting apparatus and image-forming apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electron-emitting apparatus and image-forming apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electron-emitting apparatus and image-forming apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2440983