JPS6329934B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a flat discharge lamp in which discharge electrodes are disposed facing each other in a planar manner on the surface of an insulating substrate at minute intervals, and a fluorescent substance is coated on the surface of the insulating substrate except for the discharge electrodes. In particular, the present invention relates to a flat discharge lamp suitable for use as a light source for a device for removing static charge from a photoreceptor in an electronic copying machine or a facsimile machine, or as a backlight source for a liquid crystal display.

The flat discharge lamp of the present invention can be used in various fields, such as for removing static charge from photoreceptors in electronic copying machines and facsimile machines, or as a back light source for liquid crystal displays. Examples of its use include electronic copying machines. A case where the present invention is applied to a light source for a static charge removing device for a photoreceptor and a back light source for a liquid crystal display will be described. first,
In the case of an electronic copying machine, as shown in FIG. 1, after the corona charger A uniformly distributes and charges the surface of the drum-shaped photoconductive photoreceptor B, A light image corresponding to the original to be copied is formed on the photoreceptor B in the exposure section C, and charges in the exposed portion are selectively dissipated to form a latent image corresponding to the light image. Next, in the developing section D, toner is attached to the latent image by electrostatic force and visualized to form a toner image E. Furthermore, in order to facilitate the transfer, the toner is attached to the latent image by a first static charge removing device F. After removing the charge from the toner image E, a transfer section G electrostatically transfers the toner image E onto a copy sheet H, and a fixing section I fixes it by applying heat, pressure, etc. On the other hand, the residual toner on the photoreceptor B is neutralized by the second static charge removing device J to weaken its adhesion, and is removed by a cleaning section K consisting of a brush or the like. Finally, the surface charge remaining on the photoconductive photoreceptor B is removed by the third static charge removing device L to bring the surface potential of the photoreceptor B close to zero potential, and the series of copying processes is completed.

The flat discharge lamp of the present invention can be adapted as a light source for the first, second, and third static charge removing devices F, J, and L described above, but conventionally, fluorescent lamps, incandescent lamps, and other light sources have been used as the light sources. Light bulbs or light emitting diodes were used. However, fluorescent lamps have a large diameter due to the operating temperature range, and require a ballast and starting device, making them larger and more expensive.Furthermore, the amount of light increases due to changes in ambient temperature. The problem was that temperature compensation was required to prevent changes in the temperature. In addition, although incandescent light bulbs are inexpensive, the heat generated by emitting light increases the temperature of the photoreceptor, which may change the characteristics of the photoreceptor, and may cause the filament to break during use, causing it to not light up. There were also problems with reliability. Furthermore, light emitting diodes are small, generate less heat, and are highly reliable because they are solid-state devices. However, since they are point light sources, it is necessary to arrange a large number of them in a housing, which makes the structure of the housing difficult. This method has the disadvantage that it is difficult to obtain uniformity of light emission because each light is emitted in a spot-like manner.

On the other hand, as shown in FIG. 2, the liquid crystal display M is provided with a spacer R between a front glass plate O provided with one transparent conductive electrode N and a rear glass plate Q provided with the other transparent conductive electrode P. In addition, a backlight source T including a fluorescent lamp is disposed behind the back glass plate Q.
This is because the liquid crystal S is not a self-luminous element, so it is impossible to check the display in dark conditions, and there are problems such as narrow vision when displaying using reflected light in bright ambient conditions. This is because a method is used in which light is emitted from the back and the transmitted light is used for display. Conventionally, fluorescent lamps, incandescent lamps, light emitting diodes, etc. have been used as the light source, but there are problems with this as mentioned above in the example of the light source for the device for removing static charge from the photoreceptor of an electronic copying machine. Conventional light sources are not thin and cannot take advantage of the thin characteristics of LCDs.
There was a demand for a thin and simple light source.

Furthermore, in terms of emission wavelength, from the viewpoint of compatibility with the photoreceptor material, as a light source for a device for removing static charge from a photoreceptor such as an electronic copying machine or a facsimile machine,
A light source with an emission wavelength in the range of 400 to 650 nm is required, and as a back light source for a liquid crystal display, a light source with an emission wavelength of 600 to 650 nm (red) or 500 nm is required for color display using a guest-host liquid crystal in addition to monochrome display.
A light source with spectral characteristics from 530 nm (green) and from 410 to 450 nm (blue) is needed.

The present invention has been devised in view of the above-mentioned points, and has a flat structure, a simple drive circuit, little heat generation, and uniform light emission of any wavelength depending on the purpose. It is an object of the present invention to provide a flat discharge lamp that has excellent performance such as high reliability, has a simple structure, is easy to manufacture, and is inexpensive.

In order to achieve the above objects, the structure of the present invention is as follows:
A plurality of ribbon-shaped or linear discharge electrodes arranged in a column on a rear substrate made of an electrical insulator, and a ribbon-shaped discharge electrode facing the one discharge electrode with a small interval in a plane. Alternatively, a linear other discharge electrode is disposed, and a fluorescent material is applied except for the discharge electrode portion, and a microspace is separated from the back substrate so as to cover the discharge electrode and the fluorescent material. Then, a transparent front substrate made of an electrical insulator is placed, and the peripheries of both substrates are sealed in vacuum to form a vacuum container, and a fluorescent substance is excited and emitted light by electric discharge inside the container. This flat discharge lamp is characterized by being filled with an ultraviolet emitting gas mainly composed of rare gases. An embodiment of the present invention will be described below with reference to the drawings.

3A and 3B are a plan view and a perspective view of the main parts of a flat discharge lamp according to an embodiment of the present invention, respectively. In the figures, 1 is the entire flat discharge lamp, 2 is the rear substrate, and 3 is one side. 3' is the other discharge electrode, 4 is a fluorescent substance, 5 is a front substrate, and 6 is a vacuum vessel.

Thus, in the flat discharge lamp 1 of this embodiment, a plurality of ribbon-shaped or linear discharge electrodes 3 are arranged in tandem on the surface of an elongated back substrate 2 made of an electrical insulator such as glass or ceramic. arranged,
Corresponding to each of the discharge electrodes 3, a plurality of ribbon-shaped or linear discharge electrodes 3' are arranged in columns and arranged in a plane at minute intervals. The discharge electrodes 3 and 3' are each provided with lead wires 7 and 7', and in this case, the discharge electrodes 3 and 3' and the lead wires 7 and 7' are formed mainly by printing technology, vapor deposition technology, or noble gas. It can be easily formed by depositing iron, nickel, chromium, or an alloy thereof in a predetermined pattern using a plasma spraying technique using a reducing gas. The terminals are baked with silver paste or gold paste to increase mechanical strength and reduce contact resistance. In addition, the discharge electrodes 3, 3'
The surface of is BaO, BaSrO ₂ , BaSrCaO ₃ ,
Cs ₂ O, Y ₂ O ₃ , BaAl ₂ O ₄ , BaS, LaB ₆ or GdB ₆
Electron-emitting materials 8, 8' consisting of a single substance or a composite of , etc. are deposited by dissolving an organic metal in an organic solvent and applying it, or by a plasma spraying technique, etc., and a discharge electrode is placed in the discharge space. The aim is to lower the operating voltage, which tends to be higher than in the conventional case. Furthermore, on the surface of the rear substrate 2, except for the discharge electrodes 3 and 3', red light emitting,
A fluorescent substance 4 that emits light at a wavelength depending on the purpose of use, such as green light emission, blue light emission, or white light emission by a mixture of these, is appropriately selected and deposited. I am trying to use it.

On the other hand, a spacer 9 is interposed on the front surface of the rear substrate 2 so as to cover the discharge electrodes 3, 3', the fluorescent material 4, the lead wires 7, 7', and the electron radioactive materials 8, 8'. An elongated front substrate 5 made of a translucent electrical insulator such as glass is placed across a microspace, and a fluorescent material 4 is thinly coated on its inner surface, that is, the surface facing the rear substrate 2. In the operating state, the luminescence of the fluorescent material 4 is utilized in the form of transmitted light.

Then, the periphery of the back substrate 2 and front substrate 5 is vacuum-sealed with a sealing material such as frit glass to form a vacuum container 6.
An ultraviolet emitting gas mainly composed of a rare gas such as Xe is sealed, and the phosphor 54 is excited and emitted light by the ultraviolet rays generated by the glow discharge of the rare gas, and the reflected light from the fluorescent substance 4 on the rear substrate 2 and the front Bright light is obtained by superimposing the transmitted light of the fluorescent substance 4 deposited on the inner surface of the substrate 5.

FIG. 4 is a perspective view of a main part of another embodiment, in which a plurality of ribbon-shaped or linear discharge electrodes 3 are arranged in a column on the rear substrate 2, and one of the discharge electrodes 3 is disposed in a column. 3 and the other discharge electrode 3', which is in the form of a ribbon or a line, is arranged to face the other discharge electrode 3' at a small interval in a plane, and lead wires 7, 7', respectively.
The structure derives the following.

Another embodiment of the present invention shown in FIG. 5 includes a plurality of ribbon-shaped or linear discharge electrodes 3 arranged in a column, and a single strip facing the discharge electrodes 3 in a plane with a small interval therebetween. Two pairs of ribbon-shaped or linear discharge electrodes 3' are disposed on the rear substrate 2, and the number of pairs of discharge electrodes 3, 3' can be increased. Since the flat discharge lamp of this example has a wide light emitting area, it can be said to be suitable as a back light source for a liquid crystal display.

The embodiment shown in FIG. 6 has a structure in which a plurality of discharge electrodes 3 on one side and a single discharge electrode 3' on the other hand in the embodiment shown in FIG. 4 are arranged in a zigzag pattern.
The excited light emission of the fluorescent substance 4 becomes uniform, and uniform light emission can be obtained over the entire light emitting surface.

FIG. 7 shows a rear substrate 2 of still another embodiment of the present invention.
FIG. In this embodiment, the discharge electrodes 3 and 3' on the rear substrate 2 are constructed of L-shaped wire-like electrodes.One discharge electrode 3 is a plurality of wire-like electrodes arranged in a column, and the other discharge electrode 3 is arranged in a column. It has a configuration in which a single wire-like electrode is disposed as the discharge electrode 3'. In this case, the tip of the L-shaped wire-shaped electrode is used as a lead wire, which is led out to the back surface of the back substrate 2 through through holes 10 and 10' formed in the back substrate 2.

Furthermore, regarding the embodiments shown in FIGS. 4 to 7, the electron radioactive substances 8,
8', the deposition of the fluorescent material 4 on the rear substrate 2 and the front substrate 5, the materials and arrangement of the rear substrate 2 and the front substrate 5, the arrangement of the gas, etc., are as shown in the embodiment shown in FIG. is essentially the same as

FIG. 8 and FIG. 9 show a drive circuit for causing a flat discharge lamp to discharge and emit light according to an embodiment of the present invention.
The drive circuit in FIG. 8 is applied to drive the embodiment shown in FIG. 3, and the drive circuit in FIG. 9 is applied to drive the embodiments shown in FIGS. 4 to 7. The lead wires 7, 7' are connected to a commercial frequency AC power source 12 via a current limiting resistor 11, and are driven in an AC discharge state. As described above, the flat discharge lamp drive circuit of the present invention has a very simple structure because it does not require a ballast, a starter device, or a temperature compensation structure as in a fluorescent lamp. In the above-mentioned drive circuit, the commercial AC power supply 12 was used as an example of the power source, but if it is necessary to drive at a low voltage of several volts to several tens of volts, a DC
- It can be operated in a high frequency discharge mode using an AC converter or an AC-AC converter.

As described above, the flat discharge lamp of the present invention has a structure in which a vacuum container is formed by the back substrate and the front substrate on which the discharge electrode and the fluorescent material are arranged, and the ultraviolet emitting gas is sealed inside. It has a simple structure and drive circuit, generates little heat, and can emit uniform light as well as emit light of any wavelength.
In addition, it has many excellent features such as high reliability with no risk of wire breakage, etc. In particular, it has a flat structure, which is advantageous in terms of mounting, and it is also suitable for mass production and has a low price, making it practical. It is of great value.

[Brief explanation of the drawing]

FIG. 1 is a schematic structural diagram of an electronic copying machine, FIG. 2 is a partial cross-sectional perspective view of a liquid crystal display, and FIGS. 3 A and B are a plan view and a perspective view of essential parts, respectively, showing an embodiment of the present invention. 4 to 6 are plan views of essential parts showing other embodiments of the present invention, FIG. 7 is a perspective view of essential parts of other embodiments of the present invention, and FIGS. 8 and 9 are 1 is a drive circuit for a flat discharge lamp according to an embodiment of the present invention. 1... flat discharge lamp, 2... rear substrate, 3,
3'...discharge electrode, 4...fluorescent material, 5...front substrate, 6...vacuum container.

Claims (1)

[Claims] 1. A plurality of ribbon-shaped or linear discharge electrodes arranged in a column on a back substrate made of an electrical insulator, and a micro-interval between the discharge electrodes and the discharge electrodes in a plane. A ribbon-shaped or linear discharge electrode is arranged facing away from the other discharge electrode, and a fluorescent substance is applied except for the discharge electrode part, and the above-mentioned electrode is coated with a fluorescent substance so as to cover the discharge electrode and the fluorescent substance. A translucent front substrate made of an electrical insulator is placed between the back substrate and a small space, and the peripheries of both substrates are vacuum-sealed to form a vacuum container. A flat discharge lamp characterized in that it is filled with an ultraviolet emitting gas mainly consisting of a rare gas that excites a fluorescent substance to emit light. 2. Claim 1, wherein the other discharge electrode is a plurality of discharge electrodes arranged in a column in correspondence with each of the one discharge electrode.
The flat discharge lamp described in Section 1. 3. The flat discharge lamp according to claim 1, wherein the other discharge electrode is a single discharge electrode corresponding to all of the one discharge electrode. 4. The flat discharge lamp according to any one of claims 1 to 3, wherein the surfaces of one and the other discharge electrodes are coated with an electron emitting material. 5. The flat discharge lamp according to any one of claims 1 to 4, wherein the front substrate has a fluorescent substance coated on its inner surface.