JPS6332222B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-frequency discharge lamp in which discharge electrodes, each of which has a linear electrode base covered with a dielectric and a protective layer, are arranged in parallel in a discharge space. The present invention relates to a high-frequency discharge lamp that is suitable as a light source in various fields, such as a light source for neutralizing photoreceptors in machines and facsimiles, a light source for back illumination of liquid crystals, and a light source for display.

Conventionally, fluorescent lamps have been widely used as light sources for general illumination, for eliminating static from photoreceptors in electronic copying machines and facsimile machines, for backlighting liquid crystals, for display purposes, and the like. However, since these fluorescent lamps contain mercury, their operating temperature range is narrow and there is a risk of pollution problems. Due to operational and temperature considerations, the lamp diameter cannot be made smaller. The amount of light changes depending on the ambient temperature. There are filament parts at both ends of the lamp, so both ends do not emit light. High operating voltage. Difficult to turn on instantly. Since a stabilizer and a starting device are required, the entire device becomes large and expensive, and there are various problems in terms of characteristics, structure, price, etc.

The present invention was made in view of the above points, and an object thereof is to provide a high-frequency discharge lamp suitable as a light source in various fields by solving various problems such as characteristics, structure, and cost of fluorescent lamps. shall be.

In order to achieve the above object, the high-frequency discharge lamp of the present invention includes a set of two discharge electrodes and a discharge gas sealed in an airtight envelope with a phosphor layer formed on the inner wall, and a high-frequency voltage applied to the electrodes. In a high-frequency discharge lamp that discharges and emits light by a high-frequency electric field generated between the electrodes, a linear electrode base is coated with a dielectric material, and a protective layer is further formed on the dielectric material. The discharge electrode is arranged in parallel within the discharge space.

An embodiment of the present invention will be described below based on the drawings. FIG. 1 is a partially cutaway perspective view of a high-frequency discharge lamp according to an embodiment of the present invention, and FIG. 2 is a sectional view of FIG. 1, where 1 is the entire high-frequency discharge lamp, and 2 is an airtight container. , 3 is a fluorescent layer, 4 is a discharge electrode, 4a is an electrode base, 4b is a dielectric, 4c is a protective layer, and 5 is a discharge space. The high-frequency discharge lamp 1 of this embodiment has a substantially oblate cross section, and a set of two lamps are installed approximately in the center of an airtight container 2 made of a long glass tube with a phosphor layer 3 formed on the inner wall. Linear discharge electrodes 4 are arranged adjacent to each other in parallel, both ends of the electrodes 4 are led out from both ends of the airtight container 2, and one and the other of the two discharge electrodes 4 are connected to the airtight container 2.
The airtight container 2 is connected to caps 6 provided at both ends thereof, and a discharge space 5 is formed by filling a discharge gas inside the airtight container 2.
Then, a high frequency voltage is applied to the caps 6 at both ends, thereby generating a high frequency electric field between the pair of electrodes, generating a discharge, and the ultraviolet rays generated by this discharge excite the phosphor to emit light.

The discharge electrode 4 has approximately the same coefficient of thermal expansion as glass.
Fe-Ni (50:50) alloy and Ni-Cr-Fe alloy (42-
An electrode base 4a made of a metal wire such as 6 alloy is closely covered with a dielectric material 4b such as fritted glass, and a protective layer 4c is further formed thereon. Protective layer 4
Preferably, c is a material with a low work function and strong resistance to ion bombardment, such as magnesium oxide formed by coating and baking a magnesium carboxylate mixed in an organic solvent. If the two discharge electrodes are very long, it is desirable to provide a support member 7 in the middle as shown in FIG. 3 to prevent vibration. An insulating plate with adjacent electrode insertion holes, glass beads (not shown), etc. are used. Further, the distance between the two discharge electrodes 4 may be narrow as long as they do not touch each other, but it is determined mainly from the relationship with the operating voltage. Note that the operating voltage is due to the capacitive coupling between the two electrodes.
It is affected by the capacitance between the two electrodes, and is also affected by the distance between the electrodes, the surface area of the electrodes, and the dielectric constant and thickness of the dielectric and protective layer.

As the discharge gas, we use an inert gas mainly consisting of rare gases such as Ne, Ar, He, and Xe, and in particular a mixed gas mainly consisting of He and Xe, which efficiently generates ultraviolet rays that excite the phosphor. ing.

The airtight container 2 is made by welding one end of a glass tube together with one end of a set of two discharge electrodes 4, forming an exhaust pipe 8 at the other end as shown in FIG. 4, and after evacuating and filling with discharge gas. , which is obtained by leading out the other ends of the two discharge electrodes 4 and sealing off the exhaust pipe 8,
Since its thickness is not restricted by operating temperature, etc., it is possible to manufacture very thin pieces such as 6 mm or 4 mm.

In the high-frequency discharge lamp 1 having the above configuration, the dimensions of the airtight container 2 are 8 mm in major axis, 6 mm in minor axis, and 30 cm in length, and P1G1 is used as the phosphor layer 3.
42-6 alloy wire with a diameter of 0.6 mm on the electrode base 4a,
The discharge electrode 4 uses frit glass with a thickness of 1 to 20 μm as a dielectric and MgO with a thickness of 1 to 3 μm as a protective layer.
The spacing was 1 mm, a discharge gas of 2% Xe mixed with He was filled at 100 Torr, and a high frequency voltage of 10 KHZ was applied.
When the voltage was applied between the pair of electrodes 4 through the caps 6 at both ends to cause a discharge, the discharge starting voltage was 100 to 150 V, the discharge current was about 10 mA, and the emission peak wavelength was
520nm green light emitted 50ft along the entire length of the lamp
-L uniform brightness was obtained.

5 to 8 show other embodiments in which a glass tube is used for the airtight container 2. FIG. Fifth
The figure shows an example in which an airtight container 2 with a circular cross section is formed using a round tube, and uniform illumination can be obtained over the entire circumference of the high frequency discharge lamp.

FIG. 6 shows an embodiment in which one side 2a of a glass tube is formed into a flat shape, and the other side 2b opposite to this is formed into a parabolic shape to form an airtight container 2, and the discharge light is reflected by the parabolic surface. Since this light is emitted from opposing planes, it is suitable as a light source when directivity is required.

In addition to the above-mentioned container shape, the structure for imparting directivity is as shown in FIG. As shown in the structural example and FIG. 8, the phosphor layer 3a on the half surface 2a of the inner wall of the airtight container 2 is formed thin, the phosphor layer 3b on the other half surface 2b is formed thickly, and the phosphor layer 3b is further thickened. Formed half side 2
An embodiment having a structure in which a reflective layer 9 is provided on the outer wall on the b side is also effective. In the embodiment shown in FIGS. 7 and 8, the reflected light from the thick phosphor layer 3b and the thin phosphor layer 3a
Since the transmitted light is superimposed on the emitted light, a high-intensity high-frequency discharge lamp can be obtained.

The airtight container 2 can adopt various structures other than the glass tube sealed structure described in the previous embodiments, and the other embodiments shown in FIGS. A flat glass 2a is placed on the opening surface of a box-shaped container body 2b made of telite or the like and has an opening on one side, and a sealing portion 1 of fritted glass or the like is placed.
This is a high-frequency discharge lamp 1 that employs an airtight container 2 having a structure in which a discharge space 5 is formed by sealing with A thin phosphor layer 3a is formed on the inner surface of the flat glass 2a. Reference numeral 8 denotes an exhaust pipe, which is connected to the bottom of the box-shaped container main body 2b through a seal portion 10.

FIGS. 11 and 12 show still another embodiment, in which the airtight container 2 is formed of two sheets of glass. That is, a spacer 2c is inserted between a glass plate 2b on the back side and a glass plate 2a on the front side to form a discharge space 5, which is sealed with a seal part 10 to form an airtight container 2. The phosphor layer 3a on the 2a side is made thin, and the phosphor layer 3b on the rear glass 2b side is made thick, so that a thin high-frequency discharge lamp 1 can be obtained. In this embodiment, two external electrodes 6 are formed by printing on the back glass 2b extending from the end of the airtight container 2, and one end of each of the two electrodes 4 is attached to each external electrode 6. are connected, and a high frequency voltage is applied between the two external electrodes 6 to cause discharge and light to be emitted in a planar manner. Furthermore, Figure 13 shows two glass plates 2a and 2b.
This is an embodiment in which a plurality of sets of two discharge electrodes 4 are disposed between them, and a high-frequency discharge lamp 1 with a wide light emitting area can be obtained.

The high-frequency discharge lamp of the present invention described in detail above is widely used as a light source for general illumination, for eliminating static electricity from photoreceptors in electronic copying machines and facsimile machines, for back illuminating liquid crystals, for display purposes, etc. As an example of the application, a case where the present invention is applied as a static eliminator for a photoreceptor of an electronic copying machine will be described as follows. Generally, as shown in FIG. 14, a photoreceptor static eliminator 11 of an electronic copying machine is installed between devices disposed around a drum-shaped photoconductive photoreceptor 12, that is, between a charging device 13 and an exposure device 14. It is arranged between the phenomenon device 15 and the transfer device 16, between the transfer device 16 and the cleaning device 17, and between the cleaning device 17 and the charging device 13,
Each charge amount is controlled by erasing a part of the charge charged by the charging device 13. Developing device 15
By removing the charge from the toner image 18 visualized by the toner image 18, the transfer to the copy paper 19 by the transfer device 16 is facilitated. The photoreceptor 12 to which the residual toner has adhered is neutralized to weaken the adhesive force of the residual toner. Photoreceptor 1
2 to dissipate the remaining surface charge and prepare for the next copy cycle. It has the following effects.

The high frequency discharge lamp of the present invention is used in the above-mentioned static eliminator 1.
1, since the lamp diameter is small, it can be installed even if the space around the photoreceptor drum 12 is narrow, so the diameter of the photoreceptor drum 12 can be made thinner, speeding up copying, and instantaneous copying. Lighting is easy, uniform illumination characteristics are obtained over the entire lighting period, and the amount of light does not change due to the influence of ambient temperature, so there is no occurrence of copy unevenness due to poor static elimination. Furthermore, since it generates less heat, it does not affect the characteristics of the photoreceptor, and since light is emitted over the entire length of the lamp, there is no need for accessories such as ballasts, so the static eliminator can be made more compact, and copiers can be made smaller. can be achieved. On the other hand, the emission wavelength can be arbitrarily selected by appropriately selecting the discharge gas composition or the type of phosphor, so the emission wavelength can be adapted to various photoreceptors. For example, since it can be driven at a low voltage such as 6V to 24V, the drive voltage can be selected to match the various power supplies built into the copying machine, making it highly suitable for eliminating static from the photoreceptor of an electronic copying machine.

Furthermore, when used as a back light source for a liquid crystal display, the light source becomes a flat light source, and in combination with the flatness of the liquid crystal, a thin display can be obtained. Furthermore, even when the display area of the liquid crystal is large, a wide area display can be easily achieved by using a high frequency discharge lamp having a plurality of sets of discharge electrodes as shown in the embodiment of FIG. Thus, in the high frequency discharge lamp of the present invention, a set of two discharge electrodes each having a linear electrode base coated with a dielectric and a protective layer are arranged parallel to each other in a discharge space of an airtight container filled with a discharge gas. Compared to conventional fluorescent lamps, the fluorescent lamps emit light by exciting the fluorescent material formed on the inner wall of the airtight container using radiation generated by high-frequency discharge between the discharge electrodes.
Since there is no need to seal mercury in the discharge space, the operating temperature range can be widened, the lamp diameter can be made extremely thin, and the amount of light does not change even if the ambient temperature changes.
There is no need to worry about pollution. In addition, uniform light emission can be obtained over the entire length of the lamp, the operating voltage is low, and instant lighting is easy, and since no ballast or starting device is required, it can be provided in a small size and at low cost.
It can be suitably used as a light source in various fields.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view of a high-frequency discharge lamp according to an embodiment of the present invention, FIG. 2 is a sectional view of FIG. 1, and FIG. 3 is a discharge of a high-frequency discharge lamp according to an embodiment of the present invention. FIG. 4 is a schematic perspective view showing the manufacturing process of an airtight container for a high-frequency discharge lamp according to one embodiment of the present invention, and FIGS. 5 to 8 are respective other embodiments of the present invention. 9 is a partially cutaway perspective view of a high-frequency discharge lamp according to another embodiment of the present invention, FIG. 10 is a sectional view of FIG. 9, and FIG. 11 is a cross-sectional view of a high-frequency discharge lamp according to another embodiment of the present invention. A partially cutaway perspective view of a high frequency discharge lamp according to another embodiment, FIG. 12 is a sectional view of FIG. 11, and FIG. 13 is a partially cutaway perspective view of a high frequency discharge lamp according to another embodiment of the present invention. FIG. 14 is a schematic structural diagram of an electronic copying machine using a high-frequency discharge lamp as a static eliminator according to an embodiment of the present invention. 1... High frequency discharge lamp, 2... Airtight container, 3
... Fluorescent layer, 4... Discharge electrode, 4a... Electrode base, 4b... Dielectric, 4c... Protective layer, 5... Discharge space.

Claims (1)

[Claims] 1 Inside an airtight envelope with a phosphor layer formed on the inner wall,
In a high-frequency discharge lamp, a set of two discharge electrodes and a discharge gas are sealed, a high-frequency voltage is applied to the electrodes, and a high-frequency electric field generated between the electrodes discharges and emits light. 1. A high-frequency discharge lamp characterized in that the electrode base is covered with a dielectric material, a protective layer is further formed on the dielectric material to form a discharge electrode, and the discharge electrode is arranged in parallel within a discharge space.