JP4456997B2 - Cold cathode tube equipment - Google Patents

Description

  The present invention relates to a cold-cathode tube device using a cold-cathode tube (Cold Cathode Fluorescent Lamp) that emits the required visible light by applying a high voltage to the electrodes at both ends of a thin glass tube encapsulating a fluorescent material. The present invention relates to a cold cathode tube apparatus in which the strength and low temperature characteristics of the cold cathode tube are improved.

  Conventionally, it has been known that a cold cathode tube is used for a device that requires a light source, for example, a backlight of a liquid crystal display device. In a cold cathode tube used in such a liquid crystal display device, a phosphor is applied to the inner wall of an elongated glass tube, and an inert gas (Ar, etc.) and mercury are enclosed in the glass tube. Then, a high voltage is applied between the electrodes at both ends of the glass tube from the power source through the external lead wire to start discharge, and the vaporized mercury is excited by the collision with the electrons and the atoms of the encapsulated gas. (Mainly wavelength 253.7 nm) is generated. This ultraviolet light excites the phosphor and is converted into a luminescent color (visible light wavelength) due to the material and composition of the phosphor. Thereby, the cold cathode tube emits visible light.

  Such cold cathode tubes have been widely used as backlight light sources for liquid crystal television receivers and liquid crystal display devices, and a plurality of cold cathode tubes are arranged on the back side of the liquid crystal panel. (For example, refer to Patent Document 1). Usually, a cold cathode tube has a structure in which a gas is sealed inside a thin glass tube having a diameter of about 2.6 to 3 mm, for example, and is connected to an electrode inside the glass tube from an end portion. Is configured to protrude. In use, an insulating material such as a silicon rubber cap is coated on a lead wire that needs to be applied with a high voltage (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 2002-324592 JP-A-10-302611

  A conventional cold cathode tube has a diameter of about 2.1 to 3 mm, for example, and if an excessive force is applied to the glass tube, the tube is easily damaged. For this reason, when attaching to the back of the panel as the backlight of a liquid crystal panel, it is necessary to perform installation work with extreme caution so that excessive force is not applied to the glass tube. It was a technical problem. In addition, when replacing a conventional liquid crystal display device using a cold cathode tube for maintenance, there is a concern about the same damage, and it is recognized that the product cannot be replaced by maintenance by the user. It is.

  Further, with regard to the structure around the electrode, the conventional cold cathode tube has a problem that the wire diameter of the lead wire of the electrode is easily bent due to handling at the production site. The lead wire is covered with an electrode cover made of special silicon rubber, etc. and connected to a long high-insulation lead wire that is soldered, and a high voltage of 1000 volts or more is applied. Need attention.

  Furthermore, when a liquid crystal display device using a cold cathode tube is used in a low temperature facility such as a freezer room or a freezer warehouse, the temperature around the cold cathode tube is also lowered. The cold cathode tube generally has a tendency to decrease the lamp brightness in a low temperature environment. When the cold cathode tube is used in a low-temperature facility such as a freezer room or a freezer warehouse, the cold cathode tube is not sufficient. There arises a problem that luminance cannot be obtained.

  Accordingly, in view of the above technical problems, the present invention provides a cold cathode tube apparatus that prevents damage associated with the attachment or replacement of the cold cathode tube, and realizes safe and simple attachment and maintenance. With the goal. Furthermore, an object of the present invention is to provide a cold cathode tube device that can obtain sufficient light emission luminance even in a low temperature environment.

In order to solve the above technical problem, the cold cathode tube apparatus of the present invention includes a cold cathode tube in which electrodes for applying a voltage are formed at both ends and a diameter larger than that of the cold cathode tube. A translucent support tube that supports a cold cathode tube and has a vacuum around the cold cathode tube, and is disposed at both ends and the center between the cold cathode tube and the translucent support tube. An O-shaped ring member for energizing the cathode tube and the translucent support tube, and a bell-shaped support tube electrode provided at an end of the translucent support tube and connecting the cold cathode tube electrode to an external power source Part.

  By supporting the cold cathode tube inside the translucent support tube, it is possible to prevent a direct force from being applied to a relatively easily damaged material such as a thin glass tube, and the translucent support tube. By supplying a voltage with the support tube electrode portions provided at both ends of the lead wire, the problems associated with the conventional handling of the lead wire can be solved.

  According to a preferred example of the present invention, the inside of the translucent support tube is maintained in a vacuum, and heat insulation can be achieved between the outside of the translucent support tube and the cold cathode tube itself. In addition, by forming the support tube electrode portion in a substantially cylindrical shape and connecting to an external power source on the side surface, a relatively simple mounting operation is realized, and the working efficiency is greatly improved.

  According to the present invention, the cold-cathode tube itself is supported inside the translucent support tube, and against the external force or the like, the translucent support tube functions as a protective member, so that the cold-cathode tube is not damaged. Can be prevented. Therefore, it is possible to perform maintenance work and attachment work of the cold cathode tube significantly efficiently, and it is possible to reduce production costs.

  In addition, in the device that evacuates the inside of the translucent support tube, it is possible to achieve heat insulation between the outside of the translucent support tube and the cold cathode tube itself. Even when used in a low temperature facility such as a warehouse, sufficient luminance can be obtained, and the range in which the cold cathode fluorescent lamp can be used can be expanded.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 and 2 are views showing a cold cathode tube apparatus according to a first embodiment of the present invention. As shown in FIG. 1, the cold cathode tube apparatus 1 of the present embodiment has a cold cathode tube 10 in which electrodes 13 for applying a voltage are formed at both ends and a diameter larger than that of the cold cathode tube 10. A translucent support tube 12 for supporting the cold cathode tube 10 therein, and a support tube electrode unit 14 provided at an end of the translucent support tube 12 and connected to the electrode 13 of the cold cathode tube 10; 14.

  In the cold-cathode tube 10 of the cold-cathode tube device 1 having such a double structure, for example, a rare gas such as argon or neon is inside the elongated hollow glass tube 11 having a diameter of about 3 mm. Enclosed with a small amount of mercury. Electrodes 13 and 13 are provided at both ends of the glass tube 11 so as to protrude from the both ends inside the glass tube, respectively, and both ends of the glass tube 11 are sealed with a glass material. Lead wires (not shown) for applying a high voltage to the electrodes 13 and 13 are taken out from the cold cathode tube 10 from the ends sealed with the glass. Similar to a normal cold cathode tube, a phosphor is applied to the inner wall of the hollow glass tube 11, and electrons emitted from the electrode collide with an inert gas or mercury molecules when a high voltage is applied, and collide. The ultraviolet rays emitted when the mercury molecules return from the excited state to the ground state are applied to the phosphor coated on the inner wall of the glass tube 11 to generate visible light, which is emitted to the outside as the light emitting action of the cold cathode tube 10. Is irradiated. The electrodes 13 and 13 are made of a material such as nickel, molybdenum, or niobium, but are not particularly limited as long as they are suitable for an electrode of a cold cathode tube.

  In order to protect the cold cathode tube 10 that emits light by such a mechanism, the cold cathode tube device 1 of the present embodiment is provided with a translucent support tube 12 that supports the cold cathode tube 10 therein. As this translucent support tube 12, for example, a tube formed of a glass material similar to that of the cold cathode tube 10 is used, and since the diameter is larger than that of the cold cathode tube 10, the outer peripheral surface of the cold cathode tube 10 is used. The translucent support tube 12 is held so as to be substantially coaxial with the cold cathode tube 10 at a required interval. As an example, the length of the translucent support tube 12 in the axial direction is substantially the same as that of the cold cathode tube 10 and the diameter is, for example, about 6 to 10 mm. From the viewpoint of handling and manufacturing, the translucent support tube 12 is substantially cylindrical. However, it is also possible to make a part of the tube thinner or use a rectangular hollow member instead of the cylindrical tube. is there. On the inner wall of the translucent support tube 12, it is possible to add a required phosphor or a thin film such as a UV protection or UV absorber. The translucent support tube 12 has a function of preventing a force applied directly to the cold cathode tube 10 supported therein, and therefore preferably has a required rigidity as a glass tube. . Further, as will be described later, the inside of the translucent support tube 12 is maintained in a vacuum in order to improve heat insulation. For this reason, it is preferable to use a material having light permeability and high gas barrier properties, and a material suitable for keeping the inside of glass or the like in a vacuum is selected.

  Support tube electrode portions 14 and 14 respectively connected to the electrodes 13 of the cold cathode tubes 10 supported therein are provided at both ends of the translucent support tube 12. The support tube electrode portions 14 and 14 are substantially cylindrical metal members, and are connected to lead wires (not shown) so as to be electrically connected to the electrode 13 of the cold cathode tube 10 inside. Since the support tube electrode portions 14 and 14 are substantially cylindrical metal members, when a voltage is applied to the peripheral surface via a socket or the like, the voltage is applied to the electrode 13 of the cold cathode tube 10 that is internally supported. Thus, a high voltage is applied to both ends of the cold cathode tube 10. Further, since the support tube electrode portions 14 and 14 attached to both ends of the translucent support tube 12 are also physically connected to the electrode 13 of the cold cathode tube 10, these support tube electrode portions 14 and 14 and these Since the heat from the electrode portions 14 and 14 can be radiated through the socket holder in which the heat is applied, and the temperature of the electrode 13 of the cold cathode tube 10 can be lowered, the life of the cold cathode tube 10 can be extended.

  The inside of the translucent support tube 12 is maintained in a vacuum for the purpose of heat insulation and the like. For this reason, even if the temperature outside the translucent support tube 12 is low, sufficient light emission characteristics can be obtained, and even when the cold cathode tube is used in a low temperature facility such as a freezer room or a freezer warehouse, the present embodiment is implemented. Sufficient luminance can be obtained from the cold cathode tube apparatus 1 of the embodiment.

  A single or a plurality of O-shaped ring members 15 made of silicon rubber or the like as shown in FIG. 2 can be disposed inside the translucent support tube 12. Each of the cold cathode tube 10 and the translucent support tube 12 has a required bending strength with respect to the force in the bending direction, and when the O-shaped ring member 15 is provided, the translucent support tube 12 is cooled slightly. The cathode tube 10 is also slightly bent through the O-shaped ring member 15, and the strength against the overall bending can be maintained.

  The inner wall of the translucent support tube 12 can be subjected to an ultraviolet shielding process as required by a multilayer film or a required coating, and transmits visible light and does not emit ultraviolet light from the translucent support tube 12. It is also possible to shield in this way. Further, it is possible to dispose another fluorescent material or a filter at a required wavelength on the inner wall of the translucent support tube 12, and the multilayer film, the required coating, or the filter may be translucent. It is possible to provide the support tube 12 uniformly on the inner wall, but it is also possible to form it partially.

  When handling the cold cathode tube apparatus 1 of this embodiment having such a structure, the operator directly holds the translucent support tube 12 and the translucent support tube 12 against the electrode joint such as a socket. The support tube electrode portions 14 and 14 at both ends of the two can be fitted by a method of pushing in, and the installation work can proceed. Conventionally, there has been a need for handling of lead wires and soldering around the cold cathode tube 12, but the cold cathode tube apparatus 1 according to the present embodiment does not require such a complicated operation, and thus requires a short time. Simple attachment and replacement work of the cold-cathode tube 10 is realized while reliably preventing damage during operation and time.

  In the present embodiment, the shape of the cold cathode tube is linear, but the cold cathode tube may be curved, rectangular, spiral or other shapes, and may be a combination of a straight line and a curved line. It may be a shape.

  Next, another cold cathode tube apparatus according to the present embodiment will be described with reference to FIGS. The cold-cathode tube device of this embodiment has the same cold-cathode tube and translucent support tube as the cold-cathode tube device of the first embodiment, and the shape of both ends of the translucent support tube is This is an example of a little bell shape.

  The cold-cathode tube device of this embodiment has a cold-cathode tube 20 in which electrodes for applying a voltage are formed at both ends and a diameter larger than that of the cold-cathode tube 20 and supports the cold-cathode tube 20 inside. It has a translucent support tube 22 and bell-shaped support tube electrode portions 24, 24 provided at the ends of the translucent support tube 22 and connected to the electrodes of the cold cathode tube 20, respectively. .

  The cold cathode tube 20 disposed inside the translucent support tube 22 can be the same as that of the first embodiment described above, and argon or neon is formed inside the elongated hollow glass tube. In the both ends of the glass tube sealed with a rare gas such as mercury and sealed with a glass material, an electrode (not shown) protrudes from the both ends to the inside of the glass tube of the cold cathode tube 20, respectively. Is provided. Lead wires 23 (not shown) for applying a high voltage to the electrodes are taken out from the sealed end portions of the cold cathode tubes 20 to the outside of the cold cathode tubes 20 and further bell-shaped support tube electrodes to be described later. The portions 24 and 24 are extended from the pointed heads to the outside and soldered by the solder portion 26. As described above, since the lead wire 23 is electrically connected to the outer end portions of the support tube electrode portions 24 and 24 by the solder portion 26, by applying a high voltage to the support tube electrode portions 24 and 24, the translucent light is transmitted. The cold cathode tube 20 disposed inside the conductive support tube 22 emits light.

  The cold-cathode tube 20 is held by the O-shaped ring 25 so as to pass through a through-hole of an O-shaped ring 25 which is an elastic member such as silicon rubber, and is inserted into the translucent support tube 22 through the O-shaped ring 25. Supported. As in the first embodiment, the translucent support tube 22 is formed, for example, by using a glass material similar to the cold cathode tube 20 in a circular tube shape and having a diameter larger than that of the cold cathode tube 20. Therefore, the translucent support tube 22 is held so as to be substantially coaxial with the cold cathode tube 20 at a predetermined interval from the outer peripheral surface of the cold cathode tube 20. Although air, inert gas, or the like can be placed inside the translucent support tube 22, it is also possible to increase the heat insulation by making a vacuum, as in the first embodiment.

  Similar to the first embodiment described above, bell-shaped support tube electrode portions 24 respectively connected to the electrodes 23 of the cold cathode tubes 20 supported inside at both ends of the translucent support tube 22, 24 is provided. The bell-shaped support tube electrode portions 24 and 24 are metal members that are gradually reduced in diameter from the periphery of the substantially cylindrical shape and have end portions that are pointed, and are formed by the electrode 23 and the solder portion 26 of the cold cathode tube 20. Electrically connected. At the time of assembly, soldering is performed when the lead wire 23 is held so that a small amount protrudes from the tip of the support tube electrode portions 24, 24, and the electrical connection between the support tube electrode portions 24, 24 and the cold cathode tube 20 is performed. Connection is made. Further, since the support tube electrode portion 24 has a bell shape, the lead wire 23 can be easily aligned with the central axis of the support tube electrode portion 24 by guiding the lead wire 23 along the inner wall of the support tube electrode portion 24. The cold cathode tube apparatus itself can be easily assembled.

  FIG. 4 is a view showing the cold cathode tube apparatus of this embodiment together with an example of a socket, and support tube electrode portions 24 and 24 provided at both ends of a cylindrical translucent support tube 22 are attached to the socket. FIG. The socket is fixed in advance to the attachment portion 21 with screws or the like in accordance with the positions of both end portions of the translucent support tube 22. The socket has a fitting portion 27 in which a pair of bent metal plate springs are arranged to face each other with a space therebetween, and the outer peripheral portion of the metal support tube electrode portion 24 is fitted into the fitting portion 27. Thus, the translucent support tube 22 is fixed. The fitting portion 27 is provided so as to be electrically connected to the electrical connection portion 28 which is a connection piece, even if it is integral or separate, and the electrical connection portion 28 is connected to the connector 29 via wiring. The A high voltage from, for example, an inverter for driving the cold-cathode tube is supplied to the electrical connection portion 28 of both sockets via the connector 29.

  When such a socket is used, the cold cathode tube device of the present embodiment can be easily fixed to the socket by pressing the outer peripheral portion of the support tube electrode portion 24 against the end portion of the fitting portion 27 and pressing it. Since the electrical connection is completed at the same time, the assembly and replacement of the parts can be carried out very smoothly.

  In the present embodiment, the fitting portion 27 is described as being attached in a form using a pair of metal leaf springs. However, the present invention is not limited to this. For example, a through hole is provided in the socket, and a metal support tube is provided in the through hole. An attachment method in which the electrode part 24 is inserted and then fixed with a screw or the like may be used.

  Further, a cold cathode tube apparatus according to another embodiment will be described with reference to FIG. The cold-cathode tube device shown in FIG. 5 is an example in which two cold-cathode tubes 30 and 31 are disposed inside a translucent support tube 32 made of a glass tube, and support tube electrode portions 34 and 37 are arranged at both ends. Provided in each part.

  The cold cathode tubes 30 and 31 disposed inside the translucent support tube 32 can be the same as those in the first embodiment described above, and an argon hollow glass tube includes argon. A rare gas such as neon and neon is sealed together with a very small amount of mercury, and electrodes (not shown) are provided at both ends of the glass tube so as to protrude inside the glass tubes of the cold cathode tubes 30 and 31, respectively.

  In the cold cathode tube apparatus of the present embodiment, one support tube electrode portion 34 has a bell shape, and the other support tube electrode portion 37 has a cylindrical shape. One support tube electrode part 34 functions as a relay part for connecting the two cold cathode tubes 30 and 31 in series or in parallel, and, like the support tube electrode part 24 described above, the cold cathode tubes 30 and 31. Lead wires 33 taken out from the outside are extended from the tip of the bell-shaped support tube electrode portion 34 to the outside and soldered by a solder portion 36. The lead wires at the other end taken out from the cold cathode tubes 30 and 31 are respectively connected to electrode portions 38 and 39 extending on the outer peripheral portion of the other support tube electrode portion 37, and between the electrode portions 38 and 39. By applying a high voltage, a voltage is applied to the two cold cathode tubes 30 and 31, and both of the cold cathode tubes 30 and 31 disposed inside the translucent support tube 32 emit light. The electrode portions 38 and 39 are separated according to the applied voltage, but the lead wires from the cold cathode tubes 30 and 31 can be configured to be connected to the electrode portions 38 and 39 from the inside. You may make it connect after once taking out outside.

  As described above, in the cold cathode tube apparatus of the present embodiment, a plurality of cold cathode tubes can be arranged together in the support tube, which is extremely effective when arranging the cold cathode tubes at a high density. is there. In the cold cathode tube apparatus according to the present embodiment, two cold cathode tubes 30 and 31 are connected in series. However, a structure in which a plurality of cold cathode tubes are connected in parallel is shown. In addition, the cold-cathode tubes disposed inside are not necessarily selected from the same cold-cathode tube, and it is also possible to combine, for example, tubes having slightly different fluorescence wavelengths.

    FIG. 6 is a view showing an example of another cold cathode tube apparatus. The cold cathode tube apparatus of the present embodiment has a cold cathode tube similar to the cold cathode tube apparatus of the second embodiment and a translucent support tube with a bell-shaped support tube electrode portion. This is an example in which an exhaust pipe 45 is formed in the support tube electrode portion 44.

  As in the other embodiments described above, the cold cathode tube device of this embodiment also has a cold cathode tube 40 in which electrodes for applying a voltage are formed at both ends, and a diameter larger than that of the cold cathode tube 40. A translucent support tube 42 for supporting the cold cathode tube 40 therein, and a bell-shaped support tube electrode portion 43 provided at an end of the translucent support tube 42 and connected to the electrodes of the cold cathode tube 40, respectively. , 44. One bell-shaped support tube electrode portion 44 is formed with an exhaust pipe 45 having a length extending from the central portion to the pointed portion along the central axis, and the cold cathode tube 40 is interposed through the exhaust tube 45. The lead wires from the lead wires can be extended to the outside and soldered, and when the inside of the translucent support tube 42 is evacuated, gas molecules are discharged to the outside of the translucent support tube 42 through the exhaust tube 45. can do. By using the support tube electrode portion 44 having such an exhaust pipe 45, the problem of electrical connection to the cold cathode tube 40 and the problem of exhaust inside the translucent support tube can be solved simultaneously. This is extremely effective when assembling a cold cathode tube apparatus.

  In the case of using the cold cathode tube apparatus of the present invention, it is clear that excellent suitability for the temperature environment is shown, but the inventors of the present invention, as shown in FIG. The temperature of the socket part was measured about four forms. FIG. 7A shows a conventional cold cathode tube having no translucent support tube, and is configured such that a high voltage is applied from the inverter 60 to the lead wires at both ends of the cold cathode tube 50. In the apparatus shown in FIG. 7B, the cold cathode tube 50 is disposed inside the translucent support tube 52, and the support tube electrode portions 54 and 54 at both ends of the translucent support tube 52 are connected to the inverter 60 from the inverter 60. This is an example in which a voltage is applied. In the apparatus shown in FIG. 7C, a cold-cathode tube 50 is disposed inside a translucent support tube 52, and the support tube electrode portions 54, 54 at both ends of the translucent support tube 52 are connected to a high voltage from the inverter 60. In this example, a voltage is applied, and sockets 55 and 55 are attached to the support tube electrode portions 54 and 54 at both ends. The apparatus shown in FIG. 7D is an example in which aluminum radiator plates 56 are further attached to the apparatus shown in FIG.

  In the experiment, a required voltage enabling light emission from the inverter was applied to the electrode, and the temperature at the electrode portion at room temperature of 20 ° C. was measured. First, in the conventional cold cathode tube shown in FIG. 7A, the temperature of the electrode portion is increased by the radiation of heat from the cold cathode tube electrode, and a result of about 130 ° C. is obtained. Next, in the structure in which the cold cathode tube 50 shown in FIG. 7B is arranged inside the translucent support tube 52, a measured value of the electrode temperature of about 110 ° C. is obtained. It was found that the exothermic temperature was reduced by about 20 ° C. from the tube device.

Next, regarding the heat radiation efficiency by the socket, etc., when the cold cathode tube device of the present invention is attached to the socket 55 as shown in FIG. As a result, when the aluminum heat sinks 56 and 56 as shown in FIG. 7D are attached, the temperature of the socket 55 is about 40 ° C. It descends and the result of about 40 ° C. is obtained. By using the socket in this way, it can be seen that the thermal effect to the socket part is considerably reduced, and further, by using a member such as a heat sink, the temperature rise from the cold cathode tube device can be sufficiently reduced. I understood.
FIG. 8 shows an example (vacuum glass tube CCFL) in which the inside of a translucent support tube is evacuated and a cold cathode tube is arranged in the vacuum portion as a cold cathode tube device of the present invention, and a conventional cold cathode tube itself without a support tube. It is the graph which showed the brightness | luminance with respect to environmental temperature about (CCFL single pipe).

  As is apparent from FIG. 8, in the cold cathode tube apparatus (vacuum glass tube CCFL) of the present invention, there is little change from a considerably low temperature range (for example, −20 ° C.) to a high temperature range (50 to 60 ° C.). The obtained luminance intensity is obtained. On the other hand, in the conventional CCFL single tube, the relative strength deteriorates in the range below room temperature, and for example, sufficient luminance cannot be obtained in a low temperature region such as a freezer compartment. The fact that the cold cathode tube apparatus of the present invention can be applied in a wide temperature range with respect to the environmental temperature is that the inside of the translucent support tube is evacuated and has a heat insulating effect, and therefore the surroundings. This is presumably because the low temperature is not transmitted to the cold cathode tube itself even at a low temperature.

  Next, the inventors of the present invention have made a tube with respect to an example in which a cold cathode tube is disposed inside a translucent support tube (glass tube protection CCFL) and a conventional cold cathode tube itself without a support tube (CCFL single tube). The fracture strength of was measured experimentally. FIG. 9 is a diagram schematically showing the state of the experiment, in which a pipe 73 to be measured is arranged between a pair of columns 71 and 71, and in the form of a hanging load in the center of the pipe 73, The weight was suspended and the weight at which the tube 73 was broken was measured. As the tube 73, an example (cold tube protection CCFL) in which a cold cathode tube is arranged inside the above-described translucent support tube and a conventional cold cathode tube itself without a support tube (CCFL single tube) were prepared. A CCFL single tube with a diameter of 3 mm was prepared, and a glass tube protection CCFL with a diameter of 7 mm was prepared.

  As a result of this experiment, as shown in FIGS. 10A and 10B, the CCFL single tube broke the cold cathode tube with a relatively light load of about 140 grams. The tube protection CCFL broke at a weight of about 1200 grams, but it did not break at the previous stage, and it was found that the strength of the entire device was greatly improved by protecting it with a glass tube. It was.

It is a perspective view which shows an example of the cold cathode tube apparatus of this invention. It is another perspective view which shows an example of the cold cathode tube apparatus of this invention shown in FIG. It is a side view which shows another example of the cold cathode tube apparatus of this invention. It is a side view which shows another example of the cold cathode tube apparatus of this invention shown in FIG. 3 with the example of a socket. It is a side view which shows another example of the cold cathode tube apparatus of this invention. It is a side view which shows another example of the cold cathode tube apparatus of this invention. It is a figure which shows the relationship of four forms and temperature of a cold cathode tube apparatus. It is a graph which shows the relationship between environmental temperature and a brightness | luminance about each of a glass tube protection CCFL and a CCFL single tube. It is explanatory drawing of the experiment regarding a hanging load about each of a glass tube protection CCFL and a CCFL single tube. It is a figure which shows the result of the experiment regarding a hanging load about each of a glass tube protection CCFL and a CCFL single tube.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cold cathode tube apparatus 10, 20, 30, 31, 40, 50 Cold cathode tube 12, 22, 32, 42, 52 Translucent support tube 14, 24, 34, 37, 43, 44, 54 Support tube electrode part

Claims (2)

A cold cathode tube in which electrodes for applying a voltage are formed at both ends;
A translucent support tube having a diameter larger than that of the cold cathode tube and supporting the cold cathode tube therein and maintaining a vacuum around the cold cathode tube;
An O-shaped ring member disposed at both ends and the center between the cold cathode tube and the translucent support tube and energizing the cold cathode tube and the translucent support tube, respectively;
A cold-cathode tube device comprising a bell-shaped support tube electrode portion provided at an end of the translucent support tube and connecting an electrode of the cold cathode tube to an external power source.   The cold-cathode tube device according to claim 1, wherein the translucent support tube is subjected to an ultraviolet ray cut treatment.