JP3906223B2 - Barrier type cold cathode discharge lamp - Google Patents

Description

  The present invention relates to a cold cathode discharge lamp, and more particularly to a barrier type cold cathode discharge lamp.

  Unlike a fluorescent lamp, a cold cathode discharge lamp uses a cold cathode as a cathode, thereby avoiding the problem of lifetime due to the consumption of the emitter material, the disconnection of the heater coil, and the like. For this reason, cold cathode discharge lamps are widely used in various illumination light sources that require a long life, such as backlights for liquid crystal displays, and the market accounts for 20% of the total discharge lamp market.

  As described above, the cold cathode discharge lamp is a product that is extremely important and highly demanded by the market, but has two technical problems from the viewpoint of environmental load. That is, cold cathode discharge lamps are required to remove mercury and improve luminous efficiency.

  The first problem, demercury, can be achieved, for example, by using other excitation ultraviolet light source comparable to mercury instead of mercury. However, mercury is not only a high-efficiency excitation ultraviolet light source having an appropriate wavelength, but also plays a role in suppressing cold cathode material from being consumed by sputtering due to a reverse diffusion phenomenon caused by mercury vapor. For this reason, the fundamental solution is difficult with such a method.

  However, continuing to use mercury may lead to surrendering the cold cathode discharge lamp market to other illumination sources such as LEDs and organic EL. Thus, the barrier type cold cathode discharge lamp has recently been attracting attention.

  FIG. 14 is a cross-sectional view schematically showing a conventional barrier cold cathode discharge lamp. In the figure, the phosphor film is omitted. As shown in FIG. 14, the conventional barrier type cold cathode discharge lamp 101 has a structure in which conductors 104a and 104b are arranged outside a glass tube 102 in which a rare gas is sealed and a phosphor film is formed on the inner surface. ing. The discharge lamp 101 generates intermittent light between the glass walls as an insulator by applying a high-frequency voltage between the conductors 104a and 104b, and excites the phosphor with ultraviolet rays generated thereby to generate light. is there. In the discharge lamp 101, the glass wall is referred to as a barrier layer, and the laminated structure of the conductor 104a and the barrier layer and the laminated structure of the conductor 104b and the barrier layer constitute a pair of insulated electrodes.

  Thus, in this type of discharge lamp 101, the conductors 104a and 104b are not exposed to the discharge space. Therefore, it is not necessary for mercury vapor to be present in the glass tube 102 in order to prevent the conductors 104a and 104b from being consumed. Therefore, in the discharge lamp 101, only a rare gas such as xenon may be used as the gas sealed in the glass tube 102.

  However, this discharge lamp 101 is disadvantageous in terms of improving the light emission efficiency, which is the second problem described above. That is, according to the discharge lamp 101, in order to generate a discharge in the glass tube 102, the voltage is about three times that of a general cold cathode discharge lamp in which a bare conductor is arranged as an electrode inside the glass tube. Must be applied. Therefore, the discharge lamp 101 shown in FIG. 14 has a problem that the light emission efficiency is about half or less to about several tens of percent as compared with a general cold cathode discharge lamp.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a barrier-type cold cathode discharge lamp capable of realizing high luminous efficiency.

According to the first aspect of the present invention, a hollow body having a light transmission part and an opening and containing a rare gas, and a diamond insulator interposed between the first conductor and the first conductor and the space in the hollow body. A first electrode having a portion and closing the opening; a second electrode having a second conductor facing at least the first conductor through the diamond insulating portion; and a fluorescence provided on the inner surface of the hollow body A diamond film covering one main surface of the first conductor, and the main surface covered with the diamond insulating portion of the first conductor is recessed. A barrier type cold cathode discharge lamp is provided.

According to the second aspect of the present invention, a hollow body having a light transmission part and an opening and containing a rare gas, and a diamond insulator interposed between the first conductor and the first conductor and the space inside the hollow body. A first electrode having a portion and closing the opening; a second electrode having a second conductor facing at least the first conductor through the diamond insulating portion; and a fluorescence provided on the inner surface of the hollow body A body membrane, and the opening has a smaller dimension in a direction parallel to the outer surface of the wall portion where the opening of the hollow body is provided than the space in the hollow body, and the first conductor is A barrier-type cold cathode discharge lamp is provided , which covers a portion of the outer surface around the opening and the opening, and the diamond insulating portion is located in the opening .

According to the third aspect of the present invention, a hollow body having a light transmission portion and containing a rare gas, a first electrode provided with a first conductor provided on an outer surface of the hollow body, and the hollow body a phosphor film containing and diamond particles provided on the inner surface, and a second electrode having a second conductor which is opposed to the first conductor through the wall portion and the phosphor layer of at least the hollow body A barrier type cold cathode discharge lamp is provided in which the weight ratio of the diamond fine particles to the phosphor in the phosphor film is in the range of 5 to 50% .

According to a fourth aspect of the present invention, a hollow body having a light transmission part and containing a rare gas, a first electrode provided with a first conductor provided on an outer surface of the hollow body, a phosphor film containing and diamond particles provided on the inner surface, and a second electrode having a second conductor which is opposed to the first conductor with spaced apart from the previous SL provided on the outer surface of the hollow body and the first conductor And a weight ratio of the diamond fine particles to the phosphor in the phosphor film is in the range of 5 to 50% .

  Note that the “barrier cold cathode discharge lamp” here refers to at least one electrode that is exposed to the discharge space by interposing an insulator between the conductor constituting the electrode and the discharge space. It means a cold cathode discharge lamp that is not allowed to go. In this discharge lamp, since an insulator is interposed between the conductor and the discharge space, continuous discharge (charge transfer) does not occur. Therefore, high-frequency voltage is applied between the electrodes to cause light emission. . Therefore, in the barrier type cold cathode discharge lamp, light emission due to discharge and quenching due to current interruption are repeated corresponding to the voltage cycle. Such light emission and quenching based on “intermittent discharge” can be observed with a high-speed camera or the like, and is one of the features of a barrier-type cold cathode discharge lamp.

In the first to third aspects of the present invention, the second conductor may be disposed on the outer surface of the hollow body. In this case, you may provide insulating films, such as a diamond film, in the back of the surface in which the 2nd conductor of the hollow body wall part was provided.

In the first to third aspects , the second conductor may be disposed at least partially within the hollow body. In this case, the second conductor may be exposed in the hollow body, or the second electrode may further include an insulating film such as a diamond film covering a portion of the second conductor located in the hollow body.

In the first and second aspects of the present invention, diamonds insulating portion may be either of the diamond film and bulk of the diamond.

  According to the present invention, a barrier-type cold cathode discharge lamp capable of realizing high luminous efficiency is provided.

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. In each figure, the same reference numerals are given to components having the same or similar functions, and duplicate descriptions are omitted.

FIG. 1 is a sectional view schematically showing a barrier-type cold cathode discharge lamp according to a first reference example of the present invention. A barrier cold cathode discharge lamp 1 shown in FIG. 1 includes a hollow body 2, a pair of electrodes 3 a and 3 b partially inserted into the hollow body 2, and a phosphor film provided on the inner surface of the hollow body 2. 6. The electrode 3a has a conductor 4a and an insulating film 5a covering it, and similarly, the electrode 3b has a conductor 4b and an insulating film 5b covering it. The hollow body 2 is filled with a rare gas.

  According to the discharge lamp 1 shown in FIG. 1, high luminous efficiency can be realized. This will be described with reference to FIG.

  FIG. 2 is a diagram schematically showing the light emission principle of the barrier type cold cathode discharge lamp. In FIG. 2, reference numerals 11a and 11b each indicate the capacity of the barrier layer, and reference numeral 12 indicates the capacity of the discharge space. As shown in FIG. 2, in the barrier type cold cathode discharge lamp, it can be considered that the barrier layer capacitance 11a, the discharge space capacitance 12, and the barrier layer capacitance 11b are connected in series.

  In the barrier type cold cathode discharge lamp 101 shown in FIG. 14, the barrier layer capacities 11a and 11b correspond to the capacities of the wall portions of the glass tube 102, respectively, and the discharge space capacities 12 are sandwiched between those glass walls in the glass tube 102. It corresponds to the capacity of the space. Since the glass tube 102 is required to have sufficient strength, there is a limit to reducing the thickness of the wall portion. Therefore, in the discharge lamp 101 shown in FIG. 14, the barrier layer capacities 11a and 11b are small, and it is necessary to apply a high voltage to cause discharge.

  On the other hand, in the barrier type cold cathode discharge lamp 1 shown in FIG. 1, the barrier layer capacities 11a and 11b correspond to the capacities of the insulating films 5a and 5b, respectively, and the discharge space capacity 12 is the insulating film 5a and This corresponds to the capacity of the space between 5b. In this discharge lamp 1, the insulating films 5 a and 5 b only need to have a thickness that can protect the conductors 4 a and 4 b from ion bombardment, and such thickness is the wall portion of the hollow body 2. It is much thinner than the thickness. Therefore, according to the discharge lamp 1 shown in FIG. 1, the barrier layer capacities 11a and 11b can be greatly increased, and discharge can be generated at a lower voltage. That is, higher luminous efficiency can be realized.

  Further, in the discharge lamp 1 shown in FIG. 1, since the insulating films 5 a and 5 b correspond to the barrier layer, the distance between the barrier layers can be set to a desired value without depending on the size of the hollow body 2. Therefore, in the discharge lamp 1 shown in FIG. 1, it is easy to reduce the distance between the barrier layers as compared with the discharge lamp 101 shown in FIG. 14, and therefore it is possible to generate discharge at a lower voltage.

  In the discharge lamp 1 shown in FIG. 1, the insulating films 5a and 5b are preferably diamond films. When a diamond film is used as each of the insulating films 5a and 5b, rare gas ions generated by discharge collide with the insulating films 5a and 5b as compared with the case where the insulating films 5a and 5b are other insulating films such as glass. As a result, the secondary electrons emitted from the insulating films 5a and 5b significantly increase. That is, the secondary electron emission efficiency can be significantly increased. In this case, the discharge current increases rapidly immediately after the start of voltage application, and as a result, the light emission efficiency is greatly improved.

  Furthermore, the diamond film is much more resistant to ion bombardment than other insulating films. Therefore, when a diamond film is used, the insulating films 5a and 5b can be made thinner, that is, the capacity of the insulating films 5a and 5b can be increased. Therefore, it is possible to cause discharge at a lower voltage.

Hereinafter, each component of the discharge lamp 1 mentioned above is demonstrated.
The hollow body 2 has a light transmission part like a transparent glass tube, and forms an airtight space therein. The hollow body 2 is filled with a rare gas such as xenon, and the gas pressure in the hollow body 2 is normally set to about 4000 to 40000 Pa. The hollow body 2 is typically a tubular body or a flat hollow body, but may have other shapes. Moreover, the hollow body 2 does not need to be transparent as a whole as long as it has a light transmission part. Furthermore, the hollow body 2 can also be comprised by several components. Further, as will be described later, a part of the hollow body 2 can be used as a part of the electrode 3a or the electrode 3b.

  The electrode 3a has a conductor 4a and an insulating film 5a covering the conductor 4a. Similarly, the electrode 3b has a conductor 4b and an insulating film 5b covering the conductor 4b. In FIG. 1, a set of electrodes 3a and 3b is depicted, but a plurality of sets of electrodes 3a and 3b can also be used.

  The shape of the conductors 4a and 4b is not particularly limited, and the conductors 4a and 4b may be, for example, a rod shape, a plate shape, an annular shape, a spiral shape, or a comb shape. The conductors 4a and 4b may have a cross-sectional shape as shown in FIG.

    FIG. 3 is a cross-sectional view schematically showing an example of an electrode that can be used in the barrier-type cold cathode discharge lamp shown in FIG. In addition, in FIG. 3, the cross section perpendicular | vertical to the longitudinal direction of the electrode 3a is drawn. When the cross section of the conductor 4a has a concavo-convex shape as shown in FIG. 3, the insulating film 5a usually has a shape corresponding thereto. In the electrode 3a having such a structure, the insulating film 5a has a higher capacitance than the electrode 3a having a circular cross section. Therefore, it is advantageous for generating discharge at a low voltage.

  As a material for the conductors 4a and 4b, a metal material is usually used. When a diamond film is formed as the insulating films 5a and 5b, it is preferable to use molybdenum, tungsten, nickel, iron, copper, or the like as the material of the conductors 4a and 4b. When such a material is used, the diamond film can be easily formed by the CVD method.

As the insulating films 5a and 5b, it is preferable to use a film having higher resistance to ion bombardment and / or higher secondary electron emission efficiency than glass conventionally used as a barrier layer. Examples of such insulating films 5a and 5b include an AlN film, a MgO film, a LiNO ₃ film, a SiC film, or a laminate thereof in addition to a diamond film. When a diamond film is used as the insulating films 5a and 5b, the diamond film may be either single crystal or polycrystalline. In the case where a diamond film is used as the insulating films 5a and 5b, the insulating property is deteriorated due to the presence of a graphite phase. Therefore, it is desirable to prevent mixing of graphite phases in order to achieve higher insulation.

  The thickness of the insulating films 5a and 5b is preferably 5 μm or more, and more preferably 10 μm or more. Usually, when the thickness of the insulating films 5a and 5b is equal to or more than the above lower limit value, a continuous film without pinholes can be formed as the insulating films 5a and 5b, and sufficient resistance to ion bombardment is obtained. be able to. Further, as the insulating films 5a and 5b are thinner, their capacities increase. Usually, when the thickness of the insulating films 5a and 5b is 100 μm or less, the effect of improving the light emission efficiency becomes remarkable.

  The phosphor film 6 contains a phosphor such as an ultraviolet-excited phosphor generally used in a cold cathode discharge lamp. The phosphor film 6 is typically formed on the inner surface of the hollow body 2 as shown in FIG. 1, but may be provided at other positions as long as it is inside the hollow body 2.

Next, a second reference example of the present invention will be described.
FIG. 4 is a cross-sectional view schematically showing a barrier-type cold cathode discharge lamp according to a second reference example of the present invention. The barrier cold cathode discharge lamp 1 shown in FIG. 4 has the same structure as that of the discharge lamp 1 shown in FIG. 1 except that the insulating films 5a and 5b are formed as a continuous film 5 and the electrodes 3a and 3b are thereby integrated. It has almost the same structure. As shown in FIG. 4, when the electrodes 3 a and 3 b are integrated, the distance between the electrodes 3 a and 3 b does not vary in the hollow body 2. Therefore, performance can be stabilized.

In this reference example , the conductors 4a and 4b are preferably flat. This will be described with reference to FIG.

  FIG. 5 is a cross-sectional view schematically showing an example of electrodes that can be used in the barrier cold cathode discharge lamp shown in FIG. In FIG. 5, a cross section perpendicular to the longitudinal direction of the electrodes 3a and 3b is drawn. When the conductors 4a and 4b are formed in a flat plate shape as shown in FIG. 5 and their side ends face each other, the area of the insulating film 5 increases and their capacitance increases. Therefore, it is advantageous for generating discharge at a low voltage.

  4 and 5, the electrodes 3a and 3b are integrated by making the side surfaces of the conductors 4a and 4b face each other and covering them with the insulating film 5, but the electrodes 3a and 3b are formed in other forms. It is also possible to integrate them. For example, the electrodes 3a and 3b may be integrated by abutting the tips of the conductors 4a and 4b with a predetermined distance therebetween and covering them with the insulating film 5.

  There is no particular limitation on the method of integrating the electrodes 3a and 3b, and various methods can be used. For example, the conductors 4a and 4b may be disposed on one main surface of a suitable insulating substrate, and the insulating film 5 may be formed thereon. In addition, the conductor 4a is disposed on one main surface of the insulating substrate, the insulating film 5a is formed thereon, and then the conductor 4b is disposed on the surface of the insulating substrate on which the insulating film 5a is disposed, and the insulation is formed thereon. The film 5b may be formed. Further, the conductor 4a is arranged on one main surface of the insulating substrate of the insulating substrate, and after the insulating film 5a is formed thereon, the conductor 4b is arranged on the other main surface of the insulating substrate, and insulation is provided thereon. The film 5b may be formed. Also in the discharge lamp 1 shown in FIG. 1, it is preferable to integrate the electrodes 3a and 3b using a holder or the like.

Next, a third reference example of the present invention will be described.
FIG. 6 is a cross-sectional view schematically showing a barrier cold cathode discharge lamp according to a third reference example of the present invention. The barrier type cold cathode discharge lamp 1 shown in FIG. 6 has the same structure as the discharge lamp 1 shown in FIG. 4 except that the integrated electrodes 3 a and 3 b are provided so as to penetrate the hollow body 2. is doing. According to such a structure, it is possible to prevent the integrated electrodes 3 a and 3 b from fluctuating in the hollow body 2.

Next, a fourth reference example of the present invention will be described.
FIG. 7 is a cross-sectional view schematically showing a barrier cold cathode discharge lamp according to a fourth reference example of the present invention. The barrier cold cathode discharge lamp 1 shown in FIG. 7 has the same structure as the discharge lamp 1 shown in FIG. 1 except that the electrode 3b is inserted into the hollow body 2 from the opposite side to the electrode 3a. . According to such a structure, it is possible to prevent undesired discharge or the like from occurring between the conductors 4a and 4b exposed outside the hollow body 2.

Next, a fifth reference example of the present invention will be described.
FIG. 8 is a cross-sectional view schematically showing a barrier-type cold cathode discharge lamp according to a fifth reference example of the present invention. The barrier type cold cathode discharge lamp 1 shown in FIG. 8 has the same structure as that of the discharge lamp 1 shown in FIG. 1 except that the electrodes 3a and 3b are arranged so that their tips are butted. . Such a structure is advantageous for reducing the diameter of the hollow body 2, and is also useful when light control is required. In such a structure, it is preferable that the ends of the electrodes 3a and 3b are fixed using a holder or the like.

Next, a sixth reference example of the present invention will be described.
FIG. 9 is a sectional view schematically showing a barrier cold cathode discharge lamp according to a sixth reference example of the present invention. The barrier type cold cathode discharge lamp 1 shown in FIG. 9 has substantially the same structure as the discharge lamp 1 shown in FIG. 8 except that the electrode 3b is not provided with the insulating film 5b. According to such a structure, the electrode 3b is consumed, but it is possible to generate discharge at a lower voltage.

Next, a first embodiment of the present invention will be described.
FIG. 10 is a cross-sectional view schematically showing a barrier cold cathode discharge lamp according to the first embodiment of the present invention. In the barrier-type cold cathode discharge lamp 1 shown in FIG. 10, openings are provided at both ends of the hollow body 2, and these openings are respectively closed by conductors 4a and 4b. The surfaces of the conductors 4a and 4b facing the inside of the hollow body 2 are covered with diamond films 5a and 5b, respectively.

  In such a structure, since the distance between the conductors 4a and 4b depends on the shape or size of the hollow body 2, the distance between the electrodes 3a and 3b is narrowed as in the structures described in the first to sixth embodiments. It is difficult. However, in the structure shown in FIG. 10, since the diamond films 5a and 5b correspond to the barrier layer, a much higher luminous efficiency is obtained compared to the structure shown in FIG. 14 in which the glass wall corresponds to the barrier layer. It is done.

Next, a second embodiment of the present invention will be described.
FIG. 11 is a cross-sectional view schematically showing a barrier-type cold cathode discharge lamp according to the second embodiment of the present invention. In the barrier type cold cathode discharge lamp 1 shown in FIG. 11, openings are provided at both ends of the hollow body 2, and these openings are respectively closed by bulk diamonds 5a and 5b. Conductors 4a and 4b are provided on the back surface of the surface of the bulk diamond 5a and 5b facing the inside of the hollow body 2. Even with such a structure, the same effect as described with reference to FIG. 10 can be obtained.

Next, a seventh reference example of the present invention will be described.
FIG. 12 is a sectional view schematically showing a barrier cold cathode discharge lamp according to a seventh reference example of the present invention. In the barrier type cold cathode discharge lamp 1 shown in FIG. 12, conductors 4a and 4b are provided on the outer surfaces of both ends of the hollow body 2, and diamond films 5a and 5b are provided on the inner surfaces of both ends of the hollow body 2, respectively. . That is, in this discharge lamp 1, the electrode 3a is composed of the conductor 4a, the diamond film 5a, and the portion located between them, and the electrode 3b is composed of the conductor 4b, the diamond film 5b, and the hollow body 2. It is comprised with the part located between them.

  In such a structure, the laminated structure of the diamond film 5a and the wall part of the hollow body 2 and the laminated structure of the diamond film 5b and the wall part of the hollow body 2 correspond to the barrier layers, respectively. Compared with the structure described in the eighth embodiment, it is difficult to increase the capacitance of the barrier layer. However, when the diamond films 5a and 5b are used as described above, the secondary electron emission efficiency can be significantly increased. Therefore, even with the structure shown in FIG. 12, a much higher luminous efficiency can be obtained as compared with the structure shown in FIG.

  10 to 12, the electrodes 3 a and 3 b are provided at both ends of the hollow body 2, but the electrodes 3 a and 3 b may be provided at other positions. For example, when the hollow body 2 is tubular, the electrodes 3 a and 3 b may be provided on the side surface of the hollow body 2. Further, when the hollow body 2 has a flat plate shape, the electrodes 3 a and 3 b may be provided at the positions of both main surfaces of the hollow body 2.

Next, a third embodiment of the present invention will be described.
FIG. 13 is a cross-sectional view schematically showing a barrier-type cold cathode discharge lamp according to the third embodiment of the present invention. In the barrier type cold cathode discharge lamp 1 shown in FIG. 13, conductors 4 a and 4 b are provided on both outer side surfaces of the hollow body 2. That is, in this discharge lamp 1, the electrode 3a is composed of the conductor 4a and the wall portion of the hollow body 2, and the electrode 3b is composed of the conductor 4b and the wall portion of the hollow body 2. In the discharge lamp 1, diamond fine particles 5 c are mixed in the phosphor film 6.

  In such a structure, since the wall portion of the hollow body 2 corresponds to the barrier layer, it is difficult to increase the capacitance of the barrier layer as compared with the structures described in the first to eighth embodiments. . However, in this discharge lamp 1, since the fluorescent film 6 is provided between the electrodes 3a and 3b, ions generated by the discharge are accelerated toward the fluorescent film 6, and the fluorescent film 6 is accompanied by a large kinetic energy. It collides with the diamond fine particles 5c inside. Therefore, even with the structure shown in FIG. 13, high secondary electron emission efficiency can be realized, and therefore, much higher light emission efficiency can be obtained as compared with the structure shown in FIG.

  In the present embodiment, the phosphor film 6 in which the diamond fine particles 5c are mixed is prepared as a slurry containing the phosphor, the diamond fine particles 5c, and a binder material if necessary, and this is applied to the inner surface of the hollow body 2. It can be formed by coating. The surface of the diamond fine particles 5c is preferably preliminarily treated with hydrogen. The weight ratio of the diamond fine particles 5c to the phosphor is preferably about 5 to 50%. In this case, the operating voltage can be reduced by about 10% compared to the case where the diamond fine particles 5 c are not mixed in the phosphor film 6.

In the first to seventh reference examples and the first to third embodiments described above, the structure of the electrode 3a and the structure of the electrode 3b are the same except for the sixth reference example , but they are different from each other. It may be. That is, the structures described in the first to seventh reference examples and the first to third embodiments can be combined with each other.

Examples of the present invention will be described below.
( Example )
In this example, the efficiency of secondary electron emission was compared between diamond and glass by the method described below.

First, a seeding process was performed on the surface of a 4 mm × 4 mm molybdenum substrate by ultrasonic cleaning using a suspension containing diamond fine powder. Next, a diamond film was formed by CVD on the surface of the molybdenum substrate that had been seeded. Here, as the diamond film, a gas containing CH ₄ and H ₂ is used as a source gas, the film forming temperature is set to 800 to 900 ° C., and excitation is performed by microwave plasma, so that the dense film having a thickness of 20 μm is formed. A crystalline diamond film was formed. With the above method, a pair of laminated structures each having a molybdenum substrate and a diamond film were formed.

  Next, these laminated structures were arranged in a 8000 Pa xenon atmosphere so that the diamond films face each other, and a high frequency voltage of 50 kHz was applied between the molybdenum substrates. The distance between the substrates was 3 mm. As a result, discharge occurred when the power supply voltage was increased to about 600V.

  Next, a test similar to the above was performed on a laminated structure having a molybdenum substrate and a glass film. The film thickness of the glass film was the same as that of the diamond film. As a result, the power supply voltage had to be increased to about 800 V in order to cause discharge.

( Reference example )
In this reference example , the barrier type cold cathode discharge lamp 1 shown in FIG. 1 was produced by the method described below.
First, diamond films 5a and 5b were formed on the surfaces of conductors 4a and 4b made of molybdenum and having a diameter of 1 mm to form electrodes 3a and 3b, respectively. The diamond films 5a and 5b were formed under the same conditions as described in the example , and their thickness was 50 μm. Next, the phosphor film 6 was formed by the coating method on the inner surface of the glass tube 2 having an inner diameter of 4 mm and having one end opened and the other end sealed. Next, glass beads were applied to the electrodes 3a and 3b, and the electrodes 3a and 3b were inserted into the glass tube 2 having the phosphor film 6 formed on the inner surface. Furthermore, the glass tube 2 was sealed by fusing the glass bead and the opening of the glass tube 2 in a 8000 Pa xenon atmosphere. The discharge lamp 1 shown in FIG. 1 was produced as described above. In this reference example , the electrodes 3a and 3b were positioned within the glass tube 2 up to 150 mm from the tip. The distance between the electrodes 3a and 3b was 1 mm.

  Next, regarding the discharge lamp 1 manufactured by the above-described method, the light emission characteristics when a high frequency voltage of 50 kHz was applied between the electrodes 3a and 3b were examined. As a result, light emission was observed when the power supply voltage was increased to 420V.

(Comparative example)
In this comparative example, the barrier type cold cathode discharge lamp 101 shown in FIG. 14 was produced by the method described below.
First, a phosphor film 106 was formed on the inner surface of a glass tube 102 having an inner diameter of 4 mm, having one end opened and the other end sealed. In addition, the thickness of the wall part of the glass tube 102 used here was 0.5 mm. Next, it sealed by fusing the opening part of the glass tube 2 in a 8000 Pa xenon atmosphere. Further, conductors 104a and 104b each having a length of 150 mm and a width of 2 mm were attached to the outer surface of the glass tube 2. As described above, the discharge lamp 101 shown in FIG. 14 was produced.

Next, the light emission characteristics of the discharge lamp 101 manufactured by the method described above were examined under the same conditions as described in the examples . As a result, light emission was observed when the power supply voltage was increased to 1500V.

Sectional drawing which shows roughly the barrier type cold cathode discharge lamp which concerns on the 1st reference example of this invention. The figure which shows roughly the light emission principle of a barrier type cold cathode discharge lamp. Sectional drawing which shows roughly an example of the electrode which can be used with the barrier type cold cathode discharge lamp shown in FIG. Sectional drawing which shows schematically the barrier type cold cathode discharge lamp which concerns on the 2nd reference example of this invention. Sectional drawing which shows schematically an example of the electrode which can be used with the barrier type cold cathode discharge lamp shown in FIG. Sectional drawing which shows schematically the barrier type cold cathode discharge lamp which concerns on the 3rd reference example of this invention. Sectional drawing which shows schematically the barrier type cold cathode discharge lamp which concerns on the 4th reference example of this invention. Sectional drawing which shows schematically the barrier type cold cathode discharge lamp which concerns on the 5th reference example of this invention. Sectional drawing which shows schematically the barrier type cold cathode discharge lamp which concerns on the 6th reference example of this invention. 1 is a cross-sectional view schematically showing a barrier cold cathode discharge lamp according to a first embodiment of the present invention. Sectional drawing which shows schematically the barrier type cold cathode discharge lamp which concerns on the 2nd Embodiment of this invention. Sectional drawing which shows schematically the barrier type cold cathode discharge lamp which concerns on the 7th reference example of this invention. Sectional drawing which shows roughly the barrier type cold cathode discharge lamp which concerns on the 3rd Embodiment of this invention Sectional drawing which shows the conventional barrier type cold cathode discharge lamp roughly.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Barrier type cold cathode discharge lamp, 2 ... Hollow body, 3a, 3b ... Electrode, 4a, 4b ... Conductor, 5, 5a, 5b ... Insulating film, 5c ... Diamond fine particle, 6 ... Phosphor film, 11a, 11b ... Barrier layer capacity, 12 ... discharge space capacity, 101 ... barrier type cold cathode discharge lamp, 102 ... glass tube, 104a, 104b ... conductor.

Claims (4)

A hollow body having a light transmission part and an opening and containing a rare gas;
A first electrode comprising a first conductor and a diamond insulating portion interposed between the first conductor and a space in the hollow body and closing the opening;
A second electrode comprising a second conductor facing the first conductor through at least the diamond insulating part;
A phosphor film provided on the inner surface of the hollow body,
The diamond insulating part is a diamond film covering one main surface of the first conductor,
The barrier type cold cathode discharge lamp, wherein the main surface of the first conductor covered with the diamond insulating portion is recessed. A hollow body having a light transmission part and an opening and containing a rare gas;
A first electrode comprising a first conductor and a diamond insulating portion interposed between the first conductor and a space in the hollow body and closing the opening;
A second electrode comprising a second conductor facing the first conductor through at least the diamond insulating part;
A phosphor film provided on the inner surface of the hollow body,
The opening has a smaller dimension in a direction parallel to the outer surface of the wall portion where the opening of the hollow body is provided, compared to the space in the hollow body,
The first conductor covers a portion of the outer surface around the opening and the opening,
The barrier type cold cathode discharge lamp, wherein the diamond insulating portion is located in the opening. A hollow body having a light transmission part and containing a rare gas;
A first electrode provided with a first conductor provided on the outer surface of the hollow body;
A phosphor film provided on the inner surface of the hollow body and containing diamond fine particles;
Comprising at least a second electrode provided with a second conductor facing the first conductor via the wall of the hollow body and the phosphor film;
The barrier type cold cathode discharge lamp according to claim 1, wherein the weight ratio of the diamond particles to the phosphor in the phosphor film is in the range of 5 to 50%. A hollow body having a light transmission part and containing a rare gas;
A first electrode provided with a first conductor provided on the outer surface of the hollow body;
A phosphor film provided on the inner surface of the hollow body and containing diamond fine particles;
A second electrode provided on the outer surface of the hollow body and provided with a second conductor spaced from the first conductor and facing the first conductor ;
The barrier type cold cathode discharge lamp according to claim 1, wherein the weight ratio of the diamond particles to the phosphor in the phosphor film is in the range of 5 to 50%.

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