JP2010212124A - Low-pressure discharge lamp, lighting system, and image display - Google Patents

Abstract

An object of the present invention is to prevent a sealing portion of a glass bulb from being damaged even if a portion of the surface of a lead wire located outside the glass bulb is covered with solder. Also, even if the portion of the surface of the lead wire of the low-pressure discharge lamp provided inside is covered with solder, the solder enters between the glass bulb and the lead wire, and the glass bulb is sealed when it is lit. The purpose is to prevent the landing part from being damaged.
A glass bulb 101, an electrode 102 disposed inside the glass bulb 101, and a lead wire 103 having one end connected to the electrode 102 and the other end led out of the glass bulb 101 are provided. In the low-pressure discharge lamp 100, an oxide film 106 is formed in a portion of the surface of the lead wire 103 located outside the glass bulb 101 and in the vicinity of the end of the glass bulb 101.
[Selection] Figure 1

Description

  The present invention relates to a low-pressure discharge lamp, an illumination device, and an image display device.

FIG. 16 shows an enlarged cross-sectional view of a main part including a tube axis of a conventional low-pressure discharge lamp. As shown in FIG. 16, a conventional low-pressure discharge lamp (hereinafter referred to as “lamp 1”) is a cold cathode discharge lamp, and includes a glass bulb 2, and a sleeve made of Ni is contained in the glass bulb 2. An electrode 3 is disposed, and a lead wire 4 that feeds power to the sleeve electrode 3 protrudes from the end of the glass bulb 2 toward the inside of the glass bulb 2 (see, for example, Patent Document 1).
JP-A-9-231942

  The lamp 1 may cover the surface with solder in order to maintain the electrical connectivity of the portion of the lead wire 4 outside the glass bulb 2.

  However, when the end of the lamp 1 is immersed in the solder bath so that the portion of the surface of the lead wire 4 located outside the glass bulb 2 is covered with solder, the solder leads to the glass bulb 2 and the lead. I could get in between line 4. In this case, since the thermal expansion coefficient is different between the solder and the glass bulb, the sealing portion of the glass bulb 2 may be damaged.

  Therefore, the low-pressure discharge lamp according to the present invention aims to prevent the sealing portion of the glass bulb from being damaged even if the portion of the surface of the lead wire that is located outside the glass bulb is covered with solder.

  Further, the illumination device and the image display device according to the present invention may be provided between the glass bulb and the lead wire even if the portion of the surface of the lead wire of the low-pressure discharge lamp provided therein is covered with the solder. The purpose is to prevent solder from entering the glass and damaging the sealing portion of the glass bulb during lighting.

  In order to solve the above problems, a low-pressure discharge lamp according to the present invention includes a glass bulb, an electrode disposed inside the glass bulb, one end connected to the electrode, and the other end connected to the glass bulb. In a low-pressure discharge lamp comprising a lead wire led outside, an oxide film is formed in the portion of the surface of the lead wire that is located outside the glass bulb, and near the end of the glass bulb. It is characterized by being.

  In the low-pressure discharge lamp according to the present invention, the length of the oxide film in the tube axis direction of the low-pressure discharge lamp is preferably in the range of 0.1 [mm] to 2.0 [mm]. .

  In the low-pressure discharge lamp according to the present invention, it is preferable that an end portion of the lead wire on the outer surface of the glass bulb and on the side opposite to the glass bulb is covered with solder.

In the low-pressure discharge lamp according to the present invention, the glass bulb preferably has a thermal expansion coefficient in the range of 3.0 × 10 ⁻⁶ [K] to 10.0 × 10 ⁻⁶ [K]. .

In the low-pressure discharge lamp according to the present invention, the glass used for the glass bulb has an oxide conversion of SiO ₂ of 60 wt% to 75 wt% and Al ₂ O ₃ of 1 wt%. 5 [wt%], B ₂ O ₃ is 0 [wt%] to 3 [wt%], Li ₂ O is 0 [wt%] to 3 [wt%], and K ₂ O is 3 [wt%] to 11 [wt%], Na ₂ O is 3 [wt%] ~10 [wt %], CaO is 0 [wt%] ~9 [wt %], MgO is 0 [wt%] ~9 [wt %], SrO Is preferably 0 [wt%] to 12 [wt%], and BaO preferably has a composition of 0 [wt%] to 11 [wt%].

  Further, in the low-pressure discharge lamp according to the present invention, the lead wire is a connection between an internal lead wire and an external lead wire, and the internal lead wire has one end connected to the electrode and the other end connected to the electrode. It is preferable to be connected to one end portion of the external lead wire in the vicinity of the outer end portion of the glass bulb.

  An illumination device according to the present invention includes the low-pressure discharge lamp.

  The image display device according to the present invention includes the illumination device.

  The low-pressure discharge lamp according to the present invention can prevent the sealing portion of the glass bulb from being damaged even if the outer surface of the glass bulb in the lead wire is covered with solder.

  The lighting device and the image display device according to the present invention can prevent the low-pressure discharge lamp provided therein from being damaged due to movement or the like.

(First embodiment)
The cross-sectional view including a low-pressure discharge lamp of the tube axis X ₁₀₀ according to a first embodiment of the present invention shown in FIG. The cold cathode discharge lamp (hereinafter referred to as “lamp 100”) according to the first embodiment of the present invention is a cold cathode fluorescent lamp, and includes a glass bulb 101 and an electrode 102 disposed inside the glass bulb 101. The lead wire 103 is connected to the electrode 102 at one end and led to the outside of the glass bulb 101 at the other end.

  The glass bulb 101 is made of, for example, borosilicate glass for sealing a tungsten wire, has a straight tube shape, and has a substantially annular cross section cut perpendicular to the tube axis. Specifically, for example, the outer diameter is 4.0 [mm], the inner diameter is 3.0 [mm], and the total length is 1000 [mm]. The glass bulb 101 is filled with, for example, 3 [mg] mercury, and a rare gas such as argon or neon is sealed at a predetermined sealing pressure, for example, 40 [Torr]. As the rare gas, for example, a mixed gas of argon and neon is used in a ratio of Ar = 10 [mol%] and Ne = 90 [mol%].

A phosphor layer 104 is formed on the inner surface of the glass bulb 101. Further, between the inner surface of the glass bulb 101 and the phosphor layer 104, for example, yttrium oxide (Y ₂ O ₃ ), silicon oxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), zinc oxide (ZnO), oxide A protective film (not shown) of a metal oxide such as titanium (TiO ₂ ) may be provided.

  The electrode 102 has a bottomed cylindrical shape, for example, an inner diameter of 2.3 [mm], an outer diameter of 2.7 [mm], a bottom thickness of 0.45 [mm], and a total length of 8.5 [mm]. mm] and made of nickel (Ni). As a material of the electrode 102, any one or more of nickel, niobium (Nb), molybdenum (Mo), tantalum (Ta), and tungsten (W) can be used.

  The electrode 102 is connected to one end of the lead wire 103. Specifically, for example, the electrode 102 is connected to one end surface of the lead wire 103 at a substantially central portion of the outer bottom surface thereof.

  The lead wire 103 includes, for example, an inner bottom wire 103a that is connected to the glass bead 105 at a part of the side surface, and the other end portion and one end portion of the inner lead wire 103a. It consists of a connection with the external lead wire 103b to be connected. Note that a connection portion between the other end portion of the internal lead wire 103 a and one end portion of the external lead wire 103 b is formed near the end portion of the glass bead 105. Further, a connection mark 103c is formed at a connection portion between the internal lead wire 103a and the external lead wire 103b.

  The internal lead wire 103a has a wire diameter of 0.8 [mm] and is made of tungsten. The internal lead wire 103a is preferably made of a material that matches the thermal expansion coefficient of the glass used as the material of the glass bulb 101 or the glass bead 105. For example, when the glass bulb 101 is borosilicate glass for sealing Kovar wire, it is preferable to use an alloy of iron, nickel, and cobalt (Kovar). Further, when the glass bulb 101 is lead-free glass, it is preferable to use an alloy of iron and nickel.

  The external lead wire 103b has a wire diameter of 0.6 [mm] and is made of nickel. The material of the external lead wire is not limited to nickel, and may be, for example, an alloy of nickel and manganese or a dumet wire.

An oxide film 106 is formed in a portion of the surface of the lead wire 103 located outside the glass bulb 101 and in the vicinity of the end of the glass bulb 101. In FIG. 1, an oxide film 106 is formed in the vicinity of the end portion of the glass bead 105 on the surface of the connection trace 103c and the external lead wire 103b. When the end portion of the lamp 100 is immersed in the solder bath by the oxide film 106, the oxide film 106 is difficult to become compatible with the solder, so that it is possible to prevent the solder from entering between the glass bulb 101 and the lead wire 103. It is possible to prevent the end of the glass bulb 101 from being damaged due to the difference in thermal expansion coefficient between the solder and the glass bulb 101. Incidentally, the tube axis X ₁₀₀ length of the oxide film 106 is preferably in the range of 0.1 [mm] or more 2.0 [mm] or less. In this case, even when the end portion of the lamp 100 is immersed in a solder bath, it is easy to suppress solder from entering between the glass bulb 101 and the lead wire 103, and a portion with good electrical connectivity of the lead wire 103 is provided. It can be secured moderately. Even more preferably, it is in the range of 0.5 [mm] or more and 1.0 [mm] or less.

  The glass bead 105 has a substantially spherical shape, and seals the internal lead wire 103a along its substantially central axis, and is made of borosilicate glass. The glass bead 105 is preferably made of the same material as the glass bulb 101 or a material having the same or similar thermal expansion coefficient as the glass bulb 101 from the viewpoint of sealing properties. In FIG. 1, the lead wire 103 is sealed to the glass bulb 101 through the glass bead 105 (indirectly sealed to the glass bulb), but is attached to the glass bulb 101 by a pinch seal method or the like. It may be sealed directly.

  A method for manufacturing the lamp 100 will be described in detail below. The lamp 100 is manufactured by using a known cold cathode fluorescent lamp manufacturing method, and after oxidizing a portion of the surface of the lead wire 103 located outside the glass bulb 101, an unnecessary oxide film is removed. To be completed. Note that the oxidation of the outer surface of the glass bulb 101 in the lead wire 103 may be left in the atmosphere for a long time, or may be separately performed by an oxidation process such as partial heating.

  A sectional view including the tube axis of the lamp 100 in the oxide film removing step is shown in FIG. 2A, and a sectional view taken along the line A-A 'in FIG. 2A is shown in FIG. 2A, the lamp 100 is a front view for convenience of explanation. The oxide film removal process shown in FIGS. 2A and 2B is electropolishing. The electropolishing is performed by immersing the end portion of the lamp 100 in an electrolysis solution 109 stored in the electropolishing layer 108 of the electropolishing apparatus 107.

  The electropolishing apparatus 107 includes an electropolishing tank 108, a first electrode 110, and a second electrode 111.

  The electrolytic polishing tank 108 is, for example, a box shape having an opening on the upper surface and is made of vinyl chloride. The electrolytic polishing tank 108 stores an aqueous phosphoric acid solution containing 40 [wt%] phosphoric acid as the electrolytic solution 109. The concentration of the phosphoric acid aqueous solution is not limited to 40 [wt%], but in order to shorten the polishing process time, the concentration of the phosphoric acid aqueous solution is within the range of 30 [wt%] or more and 50 [wt%] or less. It is preferable that Moreover, the electrolyte solution 109 is not limited to phosphoric acid aqueous solution, The well-known electrolyte solution used by electropolishing can be selected suitably, and can be used. For example, sulfuric acid aqueous solution, nitric acid aqueous solution, etc. are mentioned. However, since the phosphoric acid aqueous solution uses phosphoric acid that is not applicable to non-medicinal deleterious substances, it can be handled safely and the treatment of the waste liquid is simple. Further, since the phosphoric acid aqueous solution is colored when it becomes dirty, it is easy to determine the replacement time.

  The material of the electrolytic polishing tank 108 is not limited to vinyl chloride, and a material that is not easily eroded by the electrolytic solution 109 can be selected depending on the type of the electrolytic solution 109. When the electrolytic solution 109 is a phosphoric acid aqueous solution, the electrolytic polishing tank 108 is not easily eroded because the phosphoric acid aqueous solution has poor erodibility.

  The first electrode 110 is attached to the electrolytic polishing tank 108. The first electrode 110 includes a support portion 112 fixed to the side plate of the electropolishing tank 108 and a main body portion 113 supported by the support portion 112.

  The main body 113 is formed by bending a tungsten plate material into a substantially L shape, and includes a vertical portion 113a fixed to one end of the support portion with a screw (not shown), and a lead wire 103 of the lamp 100. And a horizontal portion 113b as a contact portion for contacting the. The main body portion 113 is supported at a predetermined height position by the support portion 112 so that the horizontal portion 113 b is accommodated in the electrolytic polishing tank 108.

  Since the main body 113 is made of tungsten, it is difficult to be electropolished even when immersed in the electrolytic solution 109 when a voltage is applied. Note that the material of the main body 113 is not limited to tungsten, and may be any material that is difficult to be electropolished.

  Since the main body 113 is a plate material bent into a substantially L shape as described above, the main body 113 itself is an elastic portion having a leaf spring structure. Therefore, when a load is applied to the horizontal portion 113b, the horizontal portion 113b rotates around the connection portion with the vertical portion 113a. For example, when the lead wire 103 is pressed and brought into contact with the upper surface of the horizontal portion 113b from above, a downward load is applied to the horizontal portion 113b, and the horizontal portion 113b is moved downward (arrows in FIGS. 2A and 2B). (Direction shown by 114).

  Thus, since the horizontal part 113b rotates when a load is applied to the horizontal part 113b, the load applied to the lead wire 103 can be reduced when the lead wire 103 is brought into contact with the horizontal part 113b. Therefore, even if the lead wire 103 is strongly pressed against the horizontal portion 113b, the lead wire 103 can be hardly bent or the lamp 100 can be hardly broken and damaged.

  The spring pressure of the leaf spring structure of the main body 113 depends on the size of the lamp 100, the diameter of the lead wire 103, the length of the outer portion of the glass bulb 101 in the lead wire 103, the moving speed of the lamp 100, and the like. Therefore, it is preferable to adjust appropriately. When the spring pressure is too strong, the lamp 100 and the lead wire 103 are bent, and when the spring pressure is too weak, the horizontal portion 113b does not return to a predetermined position.

  Further, since the main body portion 113 has a leaf spring structure, when the lead wire 103 is brought into contact with the horizontal portion 113b, the horizontal portion 113b is elastically urged toward the lead wire 103, so that the horizontal portion 113b and the lead portion are connected. The contact state with the line 103 can be stably maintained. Therefore, a current can be stably passed through the lead wire 103, and the polishing process can be performed reliably.

  The second electrode 111 is a lead bar bent in a substantially L shape, and is fixed to the side plate of the electrolytic polishing tank 108 so that one end thereof is accommodated in the electrolytic polishing tank 108.

  The first electrode 110 is connected to the anode side of a power source (not shown) via an electric wiring 115, and the second electrode 111 is connected to the cathode side of the power source via an electric wiring 116. It is connected. Since the support portion 112 and the main body portion 113 have conductivity, the first electrode 110 is electrically connected to the power source. The second electrode 111 is also electrically conductive and thus electrically connected to the power source.

  Hereinafter, an electrolytic polishing method performed using the electrolytic polishing apparatus 107 will be described.

  First, the electrolytic solution 109 is injected into the electrolytic polishing tank 108 to such an extent that at least the horizontal portion 113b of the first electrode 110 and one end portion of the second electrode 111 are immersed.

  Next, the cold cathode fluorescent lamp 100 is moved, the lead wire 103 of the cold cathode fluorescent lamp 100 is pressed against the upper surface of the horizontal portion 113b of the third electrode 3, and the lead wire 103 and the horizontal portion 113b are brought together. Make contact. A protective member 117 is wound around the base portion of the outer portion of the glass bulb 101 of the lead wire 103 of the lamp 100. This protective member has, for example, an annular shape and is made of tungsten. Even if the portion of the surface of the lead wire 103 located outside the glass bulb 101 and the vicinity of the end of the glass bulb 101 is immersed in the electrolytic solution by the protective member 117, the oxide film 106 in that portion is It can be prevented from being removed. Note that the removal range of the oxide film 106 may be managed by immersing the lead wire 103 in the electrolysis solution without using the protection member 117, but the removal range and management of the oxide film 106 is better when the protection member 117 is used. Can be easier.

  Next, a voltage is applied between the first electrode 110 and the second electrode 111, and the electrolytic solution 109 is interposed between the lead wire 103 brought into contact with the first electrode 110 and the second electrode 111. Then, a current of 0.8 [A] to 5.0 [A] is supplied for 3 [seconds] or more. As a result, the lead wire 103 functions as an anode and the second electrode 111 functions as a cathode, whereby the oxide film of the lead wire 103 is dissolved in the electrolyte 109 by an electrochemical reaction, and the surface of the lead wire 103 Of these, the portion where the protective member 117 is not wound is polished.

  Thereby, the lamp 100 is completed.

  As described above, according to the configuration of the low-pressure discharge lamp 100 according to the first embodiment of the present invention, even if the portion of the surface of the lead wire 103 located outside the glass bulb 101 is covered with solder, It is possible to prevent the sealing portion from being damaged.

Note that the oxide film regions (position, size, shape, etc.) may be different at both ends of the lamp 100. In this case, one end and the other end of the lamp 100 can be easily identified. In a cold cathode fluorescent lamp such as the lamp 100, the thickness of the phosphor layer 104 is often different between one end and the other end. When such a lamp 100 is incorporated in an illumination device (not shown) such as a backlight unit, the brightness of the entire illumination device is improved by, for example, arranging the lamps 100 so that their longitudinal directions are alternated. It suppresses unevenness. Therefore, in the assembly process of the lighting device, it is preferable that one end and the other end of the lamp 100 can be easily identified. Therefore, by forming the regions of the oxide film 106 to be different, the one end and the other end of the lamp 100 can be easily formed without marking or the like for identifying one end and the other end of the lamp 100. Can be identified. Specifically, the oxide film 106 of the oxide film 106 and the other end portion of the one end portion can be tube axis X ₁₀₀ length of the glass bulb 101 is formed differently.

(Second Embodiment)
The enlarged cross-sectional view including the tube axis X ₂₀₀ of the low-pressure discharge lamp according to a second embodiment of the present invention shown in FIG. The low-pressure discharge lamp (hereinafter referred to as “lamp 200”) according to the second embodiment of the present invention is a cold cathode fluorescent lamp.

  The lamp 200 is the first of the present invention except that the portion of the surface of the lead wire 103 that is located outside the glass bulb 101 is covered with the solder 201 at the end opposite to the glass bulb 101 side. The configuration is substantially the same as that of the low-pressure discharge lamp 100 according to the embodiment.

  As described above, according to the configuration of the low-pressure discharge lamp 200 according to the second embodiment of the present invention, it is possible to prevent the sealing portion of the glass bulb 101 from being damaged. Furthermore, it is possible to prevent the portion of the surface of the lead wire 103 located outside the glass bulb 101 (excluding the portion where the oxide film 106 is formed) from being oxidized.

  In addition, as shown in FIG. 3, it is more preferable that the oxide film is formed in the area | region except the part in which the oxide film of the part located in the outer surface of the glass bulb 101 is formed among the surfaces of the lead wire 103. . In this case, it is possible to prevent an unnecessary oxide film from being formed in a portion where the oxide film is not formed.

(Third embodiment)
The cross-sectional view including a low-pressure discharge lamp of the tube axis X ₃₀₀ according to a third embodiment of the present invention shown in FIG. The low-pressure discharge lamp (hereinafter referred to as “lamp 300”) according to the third embodiment of the present invention is an internal / external electrode fluorescent lamp.

  The lamp 300 has an external electrode 301 on the outer surface of one end thereof, and has substantially the same configuration as the low-pressure discharge lamp 100 according to the first embodiment of the present invention, except for the configuration associated therewith. Therefore, the external electrode 301 and the configuration associated therewith will be described in detail, and description of other points will be omitted.

  The external electrode 301 is made of, for example, solder and is formed so as to cover the outer surface of one end portion of the glass bulb 101.

  The external electrode 301 may be formed by applying silver paste to the entire circumference of the electrode forming portion of the glass bulb 101, or a metal cap may be put on one end of the glass bulb 101. Further, an aluminum metal foil may be adhered so as to cover the entire outer peripheral surface of one end of the glass bulb 101 with a conductive adhesive (not shown) in which metal powder is mixed with silicone resin. . In addition, in a conductive adhesive, you may use a fluororesin, a polyimide resin, or an epoxy resin instead of a silicone resin.

Further, a protective film of, for example, yttrium oxide (Y ₂ O ₃ ) may be provided on the inner surface of the glass bulb 101 and in the region where the external electrode 301 is formed. By providing a protective film (not shown), it is possible to prevent glass scraping and pinholes that occur when mercury ions bombard that portion of the glass bulb 101.

The protective film may be made of metal oxide such as silica (SiO ₂ ), alumina (Al ₂ O ₃ ), zinc oxide (ZnO), titania (TiO ₂ ), for example, instead of yttrium oxide. In particular, when the protective film is formed of yttrium oxide or silica, mercury hardly adheres to the protective film, and mercury consumption is low.

  However, the protective film is not an essential component in the present invention and may not be formed at all, or may be formed over the entire inner surface of the glass bulb 101.

  Note that one end of the glass bulb 101 may be sealed by heating and melting one end of the glass bulb 101 without using the glass bead 105.

  As described above, according to the configuration of the low-pressure discharge lamp 300 according to the third embodiment of the present invention, even if the portion of the surface of the lead wire 103 located outside the glass bulb 101 is covered with solder, It is possible to prevent the sealing portion from being damaged.

(Fourth embodiment)
FIG. 5 shows a cross-sectional view including the tube axis X ₄₀₀ of the low-pressure discharge lamp according to the fourth embodiment of the present invention. The low-pressure discharge lamp (hereinafter referred to as “lamp 400”) according to the fourth embodiment of the present invention is a hot cathode fluorescent lamp, except that the configuration of electrodes and lead wires is different. The configuration is substantially the same as that of the low-pressure discharge lamp according to one embodiment. Therefore, hereinafter, the configuration of the electrode 401 and the lead wire 402 will be described in detail, and description of other points will be omitted.

  The electrode 401 is a tungsten filament coil, and both ends thereof are supported by a pair of lead wires 402. An emitter (not shown) is attached to the rotating portion of the electrode 401. As the emitter, for example, (Ba, Sr, Ca) O or the like can be used. The electrode may be a single winding or a double winding filament coil, but is preferably a triple winding or a quadruple filament coil. In this case, the emitter is easily attached so as to be entangled with the rotating portion of the electrode 401, and the emitter can be made difficult to drop off.

  The lead wire 402 is made of an alloy of iron (Fe) and nickel (Ni), for example. Specifically, it is preferably made of an alloy of nickel in the range of 50 [wt%] to 52 [wt%] and the remaining iron. The lead wire 402 is fixed by the glass bead 105 so as to maintain a distance between the two.

  An oxide film 106 is formed on the outer surface of the glass bulb 101 in the lead wire 402 at the end on the side of the glass bulb 101 in the same manner as the lamp 400.

  The lead wire 402 is sealed to the glass bulb 101 via the glass bead 105, but may be directly sealed to the glass bulb 101 by, for example, a pinch seal method without using the glass bead 105.

  A method for manufacturing the lamp 400 will be described in detail below. The lamp 400 is manufactured using a known hot cathode fluorescent lamp manufacturing method, and after oxidizing a portion of the surface of the lead wire 402 located outside the glass bulb 101, an unnecessary oxide film is removed. To be completed. The lead wire 402 may be oxidized on the outer surface of the glass bulb 101 by leaving the lamp 400 in the atmosphere for a long time or may be oxidized separately by an oxidation process such as partial heating.

  FIG. 6A shows a sectional view including the tube axis of the lamp in the oxide film removing step, and FIG. 6B shows a sectional view taken along the line A-A ′ of FIG. In addition, about FIG. 6A, the part of the lamp | ramp 400 is a front view for convenience of explanation. The oxide film removal process shown in FIGS. 6A and 6B is electropolishing. The oxide film removal step of the lamp 400 has substantially the same configuration as the oxide film removal step of the lamp 100 except for the configuration of the protection member 403. Therefore, the protective member will be described in detail, and description of other points will be omitted.

  The protective member 403 has a structure that covers both of a part of the surface of the pair of lead wires 402 located outside the glass bulb 101. Note that the protective member 403 is preferably conductive. In the case of a hot cathode fluorescent lamp such as the lamp 400, when the pair of lead wires are brought into contact with the horizontal portion 113b as shown in FIG. 6B, the filament is energized and the emitter may be damaged. is there. Therefore, by using a conductive material for the protective member, it is possible to prevent the emitter from being damaged by simply short-circuiting and preventing the filament from being energized.

  As described above, according to the configuration of the low-pressure discharge lamp 400 according to the fourth embodiment of the present invention, even if the portion of the surface of the lead wire 402 located outside the glass bulb 101 is covered with solder, It is possible to prevent the sealing portion from being damaged.

A hot cathode fluorescent lamp (hereinafter referred to as “lamp 404”) as shown in FIG. 7 may be used. In the lamp 404, the electrode 405 has a double spiral structure with the tube axis X101 of the glass bulb ₁₀₁ as the pivot axis. In this case, the diameter of the glass bulb 101 can be easily reduced as compared with the lamp 400. The lead wire 406 is linear and has substantially the same configuration as the lead wire 402 except for the shape.

  As shown in FIG. 7, the electrode 405 and the lead wire 406 are preferably connected via a connecting member 407. In this case, the electrode 405 and the lead wire 406 can be more reliably connected. The connection member 407 is made of nickel, for example.

  Furthermore, it is preferable to cover the periphery of the electrode 405 with a sleeve 408. In this case, scattering of the emitter from the electrode 405 can be suppressed. The sleeve 408 is, for example, nickel or iron plated with nickel, and is connected to the connection member 407.

(Fifth embodiment)
FIG. 8 shows an exploded perspective view of a lighting apparatus 500 according to the fifth embodiment of the present invention. An illumination device 500 according to the fifth embodiment of the present invention is a direct-type backlight unit, and includes a rectangular parallelepiped housing 501 having one open surface and a plurality of lamps housed in the housing 501. 100, a pair of sockets 502 for electrically connecting the lamp 100 to a lighting circuit (not shown), and an optical sheet 503 that covers an opening of the housing 501. The lamp 100 is the low-pressure discharge lamp 100 according to the first embodiment of the present invention.

  The housing 501 is made of, for example, polyethylene terephthalate (PET) resin, and a reflective surface 504 is formed by depositing a metal such as silver on the inner surface thereof. In addition, as a material of the housing | casing 501, you may comprise with metal materials, such as materials other than resin, for example, aluminum, a cold rolling material (for example, SPCC). In addition to the metal vapor-deposited film, the reflective surface 504 on the inner surface is, for example, a film in which a reflective sheet whose reflectance is increased by adding calcium carbonate, titanium dioxide or the like to polyethylene terephthalate (PET) resin is attached to the housing 501. May be.

  Inside the housing 501, a socket 502, an insulator 505, and a cover 506 are disposed. Specifically, the sockets 502 are provided at predetermined intervals in the lateral direction (vertical direction) of the housing 501 corresponding to the arrangement of the lamps 100. The socket 502 is obtained by processing a plate made of stainless steel or phosphor bronze, for example, and has a fitting portion 502a into which the external lead wire 104b is fitted. Then, the external lead wire 104b is fitted by being elastically deformed so as to expand the fitting portion 502a. As a result, the external lead wire 103b fitted into the fitting portion 502a is pressed by the restoring force of the fitting portion 502a and is difficult to come off. As a result, the external lead wire 103b can be easily fitted into the fitting portion 502a, but can be made difficult to come off.

  The socket 502 is covered with an insulator 505 so as not to short-circuit between adjacent sockets 502. The insulator 505 is made of, for example, polyethylene terephthalate (PET) resin. Note that the insulator 505 is not limited to the above structure. Since the socket 502 is in the vicinity of the electrode 103 that becomes relatively hot during operation of the lamp 100, the insulator 505 is preferably made of a heat-resistant material. As a material for the heat-resistant insulator 505, for example, polycarbonate (PC) resin, silicon rubber, or the like can be used.

  A lamp holder 507 may be provided inside the housing 501 at a place as necessary. The lamp holder 507 that fixes the position of the lamp 100 inside the housing 501 is, for example, polycarbonate (PC) resin and has a shape that follows the outer surface shape of the lamp 100. “A place where necessary” means that the deflection of the lamp 100 is caused when the lamp 100 has a long length exceeding, for example, 600 [mm], as in the vicinity of the central portion of the lamp 100 in the longitudinal direction. It is a place necessary to eliminate.

  The cover 506 divides the socket 502 from the space inside the housing 501, and is made of, for example, polycarbonate (PC) resin, keeps the periphery of the socket 502 warm, and highly reflects at least the surface on the housing 501 side. By reducing the brightness, a decrease in luminance at the end of the lamp 100 can be reduced.

  The opening of the housing 501 is covered with a light-transmitting optical sheet 503 and is sealed so that foreign matters such as dust and dust do not enter inside. The optical sheets 503 are formed by laminating a diffusion plate 508, a diffusion sheet 509, and a lens sheet 510.

  The diffusion plate 508 is a plate-like body made of, for example, polymethyl methacrylate (PMMA) resin, and is disposed so as to close the opening of the housing 501. The diffusion sheet 509 is made of, for example, a polyester resin. The lens sheet 510 is, for example, a laminate of an acrylic resin and a polyester resin. These optical sheets 503 are arranged so as to be sequentially superimposed on the diffusion plate 508.

  As described above, according to the configuration of the lighting device 500 according to the fifth embodiment of the present invention, the portion of the surface of the lead wire 103 of the low-pressure discharge lamp provided therein is covered with the solder with the solder. However, it is possible to prevent solder from entering between the glass bulb 101 and the lead wire 103 and damaging the sealing portion of the glass bulb 101 during lighting.

(Sixth embodiment)
FIG. 9 shows a partially cutaway perspective view of a lighting apparatus according to a sixth embodiment of the present invention. An illuminating device 600 according to a sixth embodiment of the present invention (hereinafter referred to as “illuminating device 600”) is an edge light type backlight unit, and includes a reflector 601, a lamp 100, a socket (not shown), and a light guide plate. 602, a diffusion sheet 603, and a prism sheet 604.

  The reflection plate 601 is disposed so as to surround the periphery of the light guide plate 602 except the liquid crystal panel side (arrow Q), and the side surface covering the bottom surface portion 601b covering the bottom surface and the side surface excluding the side where the lamp 100 is disposed. Part 601a and a curved lamp side surface part 601c covering the periphery of the lamp 100, and the light emitted from the lamp 100 is reflected from the light guide plate 602 to the liquid crystal panel (not shown) side (arrow Q). Let In addition, the reflection plate 601 is made of, for example, a film-like PET deposited with silver or a laminate of a metal foil such as aluminum.

  The socket has substantially the same configuration as the socket 502 used in the lighting apparatus 500 according to the fifth embodiment of the present invention. In FIG. 9, the end of the lamp 100 is omitted for convenience of illustration.

  The light guide plate 602 is used to guide the light reflected by the reflection plate to the liquid crystal panel side, and is made of, for example, a translucent plastic and is laminated on the reflection plate 601a provided on the bottom surface of the lighting device 600. ing. As a material, polycarbonate (PC) resin or cycloolefin-based resin (COP) can be applied.

  The diffusion sheet 603 is for expanding the visual field, and is made of, for example, a film having a diffusion transmission function made of polyethylene terephthalate resin or polyester resin, and is laminated on the light guide plate 602.

  The prism sheet 604 is for improving luminance, and is made of, for example, a sheet obtained by bonding an acrylic resin and a polyester resin, and is laminated on the diffusion sheet 603. Note that a diffusion plate may be further stacked on the prism sheet 604.

  In the case of the present embodiment, a reflective sheet (not shown) is provided on the outer surface of the glass bulb 101 except for a part in the circumferential direction of the lamp 100 (the light guide plate 602 side when inserted into the lighting device 600). An aperture-type lamp may be used.

  As described above, according to the configuration of the illuminating device 600 according to the fifth embodiment of the present invention, the portion of the surface of the lead wire 103 of the low-pressure discharge lamp 100 provided inside is positioned outside the glass bulb 101 with solder. Even when covered, it is possible to prevent solder from entering between the glass bulb 101 and the lead wire 103 and damaging the sealing portion of the glass bulb 101 during lighting.

(Seventh embodiment)
FIG. 10A shows a front view of a lighting apparatus according to the seventh embodiment of the present invention, and FIG. 10B shows a cross-sectional view taken along the line AA ′ of FIG. 10A. An illuminating device 700 (hereinafter referred to as “illuminating device 700”) according to a seventh embodiment of the present invention is a luminaire using an annular fluorescent lamp for general illumination.

  The lighting device 700 includes a main body portion 701, a plate-like portion 702, a lamp holder 703, a socket 704, and a lamp 705.

  The main body 701 accommodates a lighting circuit (not shown) and the like inside, and an electrical connection part (not shown) is led out from the upper part, for example, and the base 706 of the lamp 705 is electrically connected to the side part, for example. A socket 704 for connection is provided.

  The disc-like portion 702 is a member that supports the main body portion 701 and the lamp holder 703, and has, for example, a disc-like shape.

  The lamp holder 703 is attached to the lower surface of the plate-like portion 702, and can hold the lamp 705 by, for example, a C-shaped sandwiching piece provided at the lower end thereof, thereby preventing the lamp 705 from falling.

  The lamp 705 is an annular hot-cathode fluorescent lamp, and the low-pressure discharge lamp 400 according to the fourth embodiment, except that the shape is annular and the base 706 is located in the middle of the lamp 705. It has substantially the same configuration.

  As described above, according to the configuration of the lighting device 700 according to the seventh embodiment of the present invention, the portion of the surface of the lead wire 103 of the low-pressure discharge lamp provided inside is covered with the solder with the solder. However, it is possible to prevent solder from entering between the glass bulb 101 and the lead wire 103 and damaging the sealing portion of the glass bulb 101 during lighting.

(Eighth embodiment)
FIG. 11 shows an outline of a liquid crystal display device according to the eighth embodiment of the present invention. As shown in FIG. 11, the liquid crystal display device 800 is, for example, a 32 [inch] liquid crystal television, a liquid crystal screen unit 801 including a liquid crystal panel and the like, an illumination device 500 and a lighting circuit 802 according to the fifth embodiment of the present invention. With.

  The liquid crystal screen unit 801 is a known one and includes a liquid crystal panel (color filter substrate, liquid crystal, TFT substrate, etc.) (not shown), a drive module, etc. (not shown), and is based on an image signal from the outside. To form a color image.

  The lighting circuit 802 lights the lamp 100 inside the lighting device 500. The lamp 100 is operated at a lighting frequency of 40 [kHz] to 100 [kHz] and a lamp current of 3.0 [mA] to 25 [mA].

  FIG. 14 illustrates the case where the low-pressure discharge lamp 100 according to the first embodiment is inserted into the illumination device 500 according to the fifth embodiment of the present invention as the light source device of the liquid crystal display device 800. Not limited to the low-pressure discharge lamp 200 according to the second embodiment of the present invention, the low-pressure discharge lamp 300 according to the third embodiment of the present invention, and the low-pressure discharge lamps 400 and 406 according to the fourth embodiment of the present invention. It can also be applied. Moreover, the illuminating device 600 which concerns on the 6th Embodiment of this invention can also be used also about an illuminating device.

  As described above, according to the configuration of the liquid crystal display device according to the eighth embodiment of the present invention, the portion of the surface of the lead wire 103 of the low-pressure discharge lamp 100 provided inside is located outside the glass bulb 101 with solder. Even when covered, it is possible to prevent solder from entering between the glass bulb 101 and the lead wire 103 and damaging the sealing portion of the glass bulb 101 during lighting.

(Modification)
As described above, the present invention has been described based on the specific examples shown in the above embodiments. However, the content of the present invention is not limited to the specific examples shown in the respective embodiments. Variations can be used.

1. Modified example of low-pressure discharge lamp (1) Modified example 1
FIG. 12 shows an enlarged cross-sectional view of the main part including the tube axis of the low-pressure discharge lamp according to the first embodiment of the present invention. Modification 1 of the low-pressure discharge lamp according to the first embodiment of the present invention (hereinafter referred to as “lamp 118”) is similar to the lamp 100 except that the electrode 102 is provided with an electron-emitting material layer 119. It has substantially the same configuration. Therefore, hereinafter, the electron-emitting material layer 119 will be described in detail, and description of other points will be omitted.

  An electron emissive material layer 119 is provided on the surface of the electrode 102. In this case, the lamp voltage can be lowered compared to a lamp not provided with an electron emissive material layer. Specifically, as shown in FIG. 12, the electron emissive material layer 119 is formed on the inner surface of the electrode 102, for example. The electron emissive material layer 119 preferably contains, for example, a rare earth element. In this case, it is effective in lowering the lamp voltage in the cold cathode discharge lamp. Furthermore, the rare earth element is more preferably one or more of lanthanum (La) and yttrium (Y).

  The electron emissive material layer 119 is made of any of silicon (Si), aluminum (Al), zirconium (Zr), boron (B), zinc (Zn), bismuth (Bi), phosphorus (P), and tin (Sn). It is preferable that 1 or more types are included. In this case, the lamp voltage reduction effect can be further sustained.

  Further, the electron-emitting material layer 119 may contain a cesium (Cs) compound. In this case, the dark start characteristic of the lamp 118 can be improved. In addition to the electron emissive material layer 119, a cesium compound may be separately attached to the inner surface or the outer surface of the electrode 102.

  As the cesium compound, for example, it is preferable to use at least one of cesium sulfate, cesium aluminate, cesium niobate, cesium tungstate, cesium molybdate, and cesium chloride.

(2) Modification 2
The principal part expanded sectional view of the modification 2 of the low voltage | pressure discharge lamp which concerns on the 1st Embodiment of this invention is shown to Fig.13 (a). Modification 2 (hereinafter referred to as “lamp 120”) of the low-pressure discharge lamp according to the first embodiment of the present invention is substantially the same as the lamp 118 except that the structure of the electron-emitting material layer 121 is different. It has a configuration. Therefore, hereinafter, the electron-emitting material layer 121 will be described in detail, and description of other points will be omitted.

  The electron emissive material layer 121 is provided at the boundary between at least the inner bottom surface and the inner side surface of the electrode 102. In this case, scattering to the inner side surface of the electrode 102 can prevent scattering to the inner surface of the glass bulb 101 and the phosphor layer 104. Furthermore, the electron emissive material layer 116 is preferably formed on the inner bottom surface of the electrode 102. In this case, the material of the electron-emitting substance layer 121 can be easily formed in the electrode 102 by coating with the opening of the electrode 102 facing upward.

(3) Modification 3
The principal part expanded sectional view of the modification 3 of the low voltage | pressure discharge lamp which concerns on the 1st Embodiment of this invention is shown in FIG.13 (b). Modification 3 (hereinafter referred to as “lamp 122”) of the low-pressure discharge lamp according to the first embodiment of the present invention is substantially the same as the lamp 118 except that the structure of the electron-emitting material layer 123 is different. It has the composition of. Therefore, hereinafter, the electron-emitting material layer 123 will be described in detail, and description of other points will be omitted.

  The electron emissive material layer 123 is formed on the inner surface of the electrode 102 and decreases in thickness from the inner bottom surface of the electrode 102 toward the opening. In this case, even if the electron emissive material layer 123 in the vicinity of the opening of the electrode 102 is sputtered, the sputtered electron emissive material layer 123 from near the inner bottom of the electrode 102 is replenished, so that the effect of reducing the lamp voltage is maintained. Can be made.

(4) Modification 4
The principal part expanded sectional view of the modification 4 of the low voltage | pressure discharge lamp which concerns on the 1st Embodiment of this invention is shown to Fig.14 (a). Modification 4 (hereinafter referred to as “lamp 124”) of the low-pressure discharge lamp according to the first embodiment of the present invention has substantially the same configuration as that of the lamp 118 except that the structure of the electrode 125 is different. Have. Therefore, the electrode 125 will be described in detail below, and description of other points will be omitted.

  The electrode 125 has a bottomed cylindrical shape, and an end portion 125a on the opening side extends outward in the radial direction. In this case, the gap between the outer side surface of the electrode 125 and the inner surface of the glass bulb 101 can be reduced, preventing discharge from flowing around the outer side surface of the electrode 125 and sputtering of the outer side surface of the electrode 125. can do.

  The electron emissive material layer 119 is formed on the inner surface of the electrode 1125 except for at least the end portion 125a on the opening side that spreads outward in the radial direction of the electrode 125. Thereby, it is possible to prevent the electron-emitting material layer 119 from being scattered on the inner surface of the glass bulb 101 or the phosphor layer 104.

(5) Modification 5
The principal part expanded sectional view of the modification 5 of the low voltage | pressure discharge lamp which concerns on the 1st Embodiment of this invention is shown in FIG.14 (b). Modification 5 (hereinafter referred to as “lamp 126”) of the low-pressure discharge lamp according to the first embodiment of the present invention has substantially the same configuration as that of the lamp 100 except that the structure of the electrode 127 is different. . Therefore, the electrode 127 will be described in detail below, and description of other points will be omitted.

  The electrode 127 has a bottomed cylindrical shape, and an end portion 127a on the opening side thereof is narrowed inward in the radial direction. The electron emissive material layer 119 is provided on the inner surface of the electrode 127 except at least the end portion 127a on the opening side that extends outward in the radial direction of the electrode 127. Thus, the end portion 127 a of the electrode 127 suppresses the sputtering of the electron-emitting material layer 119, and the scattered electron-emitting material layer 119 is not the end of the electrode 127 even if the electron-emitting material layer 119 is sputtered. By being blocked by the portion 127a, scattering to the inner surface of the glass bulb 101 and the phosphor layer 104 can be prevented.

(6) Modification 6
FIG. 15A shows a front view of a sixth modification of the low-pressure discharge lamp according to the first embodiment of the present invention, and FIG. 15B shows an enlarged sectional view of the main part including the tube axis. A sixth modification (hereinafter referred to as “lamp 128”) of the low-pressure discharge lamp according to the first embodiment of the present invention is substantially the same as the lamp 100 except that the lamp 100 includes a base 129. It has a configuration. Therefore, hereinafter, the base 129 will be described in detail, and description of other points will be omitted.

  The base 129 is electrically and mechanically connected to the lead wire 103. Specifically, the base includes a body part 129 a that covers the end of the glass bulb 101, and an extension part 129 b that extends from one end of the body part 129 a and is electrically and mechanically connected to the lead wire 103. Has been. Such a lamp 128 can be electrically and mechanically connected by simply inserting the base 129 into a fuse socket (not shown) or the like when incorporated in the lighting device.

  A holding portion 129c for holding the glass bulb 101 is provided on the side surface of the body portion 129a. The holding part 129c is formed, for example, by cutting out a part of the side surface of the body part 129a and bending it to the glass bulb 101 side. Further, the tip end portion 129d of the holding portion 129c is bent to the opposite side of the glass bulb 101 so as not to damage the glass bulb 101. The holding portions 129c are preferably provided at 3 [locations] or more at substantially equal intervals in the circumferential direction of the body portion 129a. In this case, the glass bulb 101 can be held more stably. Furthermore, it is preferable that the contact portion between the holding portion 129 c and the glass bulb 101 is in a portion facing the electrode 102. In this case, heat dissipation generated near the electrode 102 can be promoted via the holding portion 129c.

  Even when the electrode 102 is provided with an electron-emitting material layer (not shown) as in Modifications 1 to 5 described above, the heat generated in the electrode 102 can be easily dissipated through the base 129. Therefore, an excessive increase in temperature around the electrode 102 is suppressed, and mercury is reduced around the electrode 102, thereby suppressing the sputtering of the electron-emitting material layer 119 and a lamp in which the base 129 is not provided. As compared with the above, the effect of reducing the lamp voltage can be maintained.

Note that the oxide film regions (position, size, shape, etc.) may be different at both ends of the lamp 128. In this case, one end and the other end of the lamp 128 can be easily identified. In the case of the lamp 128, it is conceivable that markings for identifying one end portion and the other end portion of the lamp 128 are marked on the body portion 129a of the base 129. The body portion 129a of the base 129 is an illumination device (not shown). In order to make an electrical connection, it is sandwiched, for example, in a socket. At this time, the marking may be lost due to friction. On the other hand, it is preferable that the oxide film regions (position, size, shape, etc.) are formed differently at both ends of the lamp 128 because they do not disappear due to friction with the socket. Specifically, the oxide film 106 of the oxide film 106 and the other end portion of the one end portion can be tube axis X ₁₀₀ length of the glass bulb 101 is formed differently.

2. About glass bulb 101 (1) The thermal expansion coefficient of glass bulb 101 should be in the range of 3.0 × 10 ⁻⁶ [K ⁻¹ ] to 10.0 × 10 ⁻⁶ [K ⁻¹ ]. Can do. In particular, the thermal expansion coefficient of the glass bulb 101 is preferably in the range of 8.0 × 10 ⁻⁶ [K ⁻¹ ] to 10.0 × 10 ⁻⁶ [K ⁻¹ ]. In this case, since the intensity | strength of glass becomes weak, the effect of this invention can be exhibited especially.

(2) About UV Absorption UV rays of 254 [nm] and 313 [nm] can be absorbed by doping a glass, which is a material of the glass bulb 101, with a predetermined amount of transition metal oxide depending on the type. Specifically, for example, in the case of titanium oxide (TiO ₂ ), the composition ratio of 0.05 [mol%] or more is doped to absorb ultraviolet rays of 254 [nm], and the composition ratio is 2 [mol%] or more. Thus, it is possible to absorb ultraviolet rays of 313 [nm]. However, when titanium oxide is doped more than the composition ratio of 5.0 [mol%], the glass is devitrified, so the composition ratio is 0.05 [mol%] or more and 5.0 [mol%] or less. It is preferable to dope in the range.

In the case of cerium oxide (CeO ₂ ), 254 [nm] ultraviolet rays can be absorbed by doping at a composition ratio of 0.05 [mol%] or more. However, when cerium oxide is doped more than 0.5 [mol%], the glass is colored, so cerium oxide has a composition ratio of 0.05 [mol%] to 0.5 [mol%]. It is preferable to dope in the following range. In addition, since coloring of glass by cerium oxide can be suppressed by doping tin oxide (SnO) in addition to cerium oxide, cerium oxide can be doped to a composition ratio of 5.0 [mol%] or less. . In this case, if cerium oxide is doped with a composition ratio of 0.5 [mol%] or more, ultraviolet rays of 313 [nm] can be absorbed. However, even in this case, when the composition ratio of cerium oxide is more than 5.0 [mol%], the glass is devitrified.

  In the case of zinc oxide (ZnO), ultraviolet rays having a wavelength of 254 [nm] can be absorbed by doping with a composition ratio of 2.0 [mol%] or more. However, when zinc oxide is doped more than 20 [mol%], the glass may be devitrified, so zinc oxide is in the range of 2.0 [mol%] to 20 [mol%]. It is preferable to dope.

Further, in the case of iron oxide (Fe ₂ O ₃ ), 254 [nm] ultraviolet rays can be absorbed by doping at a composition ratio of 0.01 [mol%] or more. However, when iron oxide is doped more than the composition ratio of 2.0 [mol%], the glass is colored, so the iron oxide is contained in the composition ratio of 0.01 [mol%] to 2.0 [mol%]. It is preferable to dope in the following range.

(3) Infrared transmission coefficient The infrared transmission coefficient indicating the water content in the glass that is the material of the glass bulb 101 is in the range of 0.3 to 1.2, particularly in the range of 0.4 to 0.8. It is preferable to adjust so that. If the infrared transmittance coefficient is 1.2 or less, it is easy to obtain a low dielectric loss tangent applicable to a high voltage application lamp such as a long cold cathode discharge lamp, and if it is 0.8 or less, the dielectric loss tangent is sufficient. It becomes small and becomes applicable to a high voltage application lamp.

The infrared transmittance coefficient (X) can be expressed by the following formula.
(Expression 1) X = (log (a / b)) / t
a: Transmittance [%] of a minimum point near 3840 [cm ⁻¹ ]
b: Transmittance [%] of a minimum point in the vicinity of 3560 [cm ⁻¹ ].
t: glass used in the glass bulb 101 for a glass thickness (4) lead-free glass, in terms of oxide, SiO ₂ is 60 [wt%] ~75 [wt %], Al 2 O 3 is 1 [wt%] _{~5 [wt%], Li 2} O is 0 [wt%] ~5 [wt %], K 2 O is 3 [wt%] ~11 [wt %], Na 2 O is 3 [wt%] ~12 [Wt%], CaO is 0 [wt%] to 9 [wt%], MgO is 0 [wt%] to 9 [wt%], SrO is 0 [wt%] to 12 [wt%], and BaO is 0 You may have a composition of [wt%]-12 [wt%]. In this case, an environment-friendly cold cathode discharge lamp that does not contain a lead component can be provided. Furthermore, the glass used for the glass bulb 101 has an oxide conversion of SiO ₂ of 60 [wt%] to 75 [wt%], Al ₂ O ₃ of 1 [wt%] to 5 [wt%], B _2. O ₃ is 0 [wt%] to 3 [wt%], Li ₂ O is 0 [wt%] to 5 [wt%], K ₂ O is 3 [wt%] to 11 [wt%], Na ₂ O Is 3 [wt%] to 12 [wt%], CaO is 0 [wt%] to 9 [wt%], MgO is 0 [wt%] to 9 [wt%], and SrO is 0 [wt%] to 12 [wt%]. It is more preferable that [wt%] and BaO have a composition of 0 [wt%] to 12 [wt%].

The glass used for the glass bulb 101 is, in terms of oxide, SiO ₂ of 60 [wt%] to 75 [wt%], Al ₂ O ₃ of 1 [wt%] to 5 [wt%], Li ₂ O. 0.5 [wt%] to 5 [wt%], K ₂ O 3 [wt%] to 7 [wt%], Na ₂ O 5 [wt%] to 12 [wt%], and CaO 1 [Wt%] to 7 [wt%], MgO from 1 [wt%] to 7 [wt%], SrO from 0 [wt%] to 5 [wt%], BaO from 7 [wt%] to 12 [wt] %]. In this case, it is possible to provide an environment-friendly cold cathode fluorescent lamp that is easy to process into a lamp and does not contain a lead component.

Furthermore, the glass used for the glass bulb 101 has an oxide conversion of SiO ₂ of 65 [wt%] to 75 [wt%], Al ₂ O ₃ of 1 [wt%] to 5 [wt%], B ₂ O. ₃ 0 [wt%] ~3 [wt %], Li 2 O is 0.5 [wt%] ~5 [wt %], K 2 O is 3 [wt%] ~7 [wt %], Na 2 O is 5 [wt%] to 12 [wt%], CaO is 2 [wt%] to 7 [wt%], MgO is 2.1 [wt%] to 7 [wt%], and SrO is 0 [wt%]. ] To 0.9 [wt%], and BaO may have a composition of 7.1 [wt%] to 12 [wt%]. In this case, it does not contain a lead component, has an electrical insulating property suitable for lighting applications, and can prevent devitrification. Furthermore, the glass used for the glass bulb 101 has an oxide conversion of SiO ₂ of 65 [wt%] to 75 [wt%], Al ₂ O ₃ of 1 [wt%] to 3 [wt%], B ₂ O ₃ is 0 wt% to 3 wt%, Li ₂ O is 1 wt% to 3 wt%, K ₂ O is 3 wt% to 6 wt%, Na ₂ O 7 [wt%] to 10 [wt%], CaO 3 [wt%] to 6 [wt%], MgO 3 [wt%] to 6 [wt%], SrO 0 [wt%] to 0 [wt%] It is more preferable that .9 [wt%] and BaO have a composition of 7.1 [wt%] to 10 [wt%].

(5) Shape of Glass Bulb 101 The shape of the glass bulb 101 is not limited to a straight tube shape, and may be, for example, an L shape, a U shape, a U shape, a spiral shape, or the like. Further, the cross section cut substantially perpendicular to the tube axis is not limited to a substantially circular shape, and may be a flat shape such as a track shape or a rounded round shape, an elliptical shape, or the like.

3. Regarding phosphors in the phosphor layer (1) About ultraviolet absorption For example, in recent years, with the increase in size of liquid crystal color televisions, polycarbonate with good dimensional stability has been used for the diffusion plate that closes the opening of the backlight unit. ing. This polycarbonate is easily deteriorated by ultraviolet rays having a wavelength of 313 [nm] emitted from mercury. In such a case, a phosphor that absorbs ultraviolet light having a wavelength of 313 [nm] may be used. The following phosphors absorb 313 [nm] ultraviolet rays.

(A) Blue Europium / manganese co-activated barium aluminate / strontium / magnesium [Ba _1-xy Sr _x Eu _y Mg _1-z Mn _z Al ₁₀ O ₁₇ ] or [Ba _1-xy Sr _x Eu _y Mg _{2− z} Mn _z Al ₁₆ O ₂₇ ]
Here, x, y, and z are preferably numbers satisfying the conditions of 0 ≦ x ≦ 0.4, 0.07 ≦ y ≦ 0.25, and 0 ≦ z <0.1, respectively.

Examples of such phosphors include europium activated barium magnesium aluminate [BaMg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ ], [BaMgAl ₁₀ O ₁₇ : Eu ²⁺ ] (abbreviation: BAM-B), Europium activated barium aluminate / strontium / magnesium [(Ba, Sr) Mg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ ], [(Ba, Sr) MgAl ₁₀ O ₁₇ : Eu ²⁺ ] (abbreviation: SBAM-B) Etc.

(B) Green • Manganese inactive magnesium gallate [MgGa ₂ O ₄ : Mn ²⁺ ] (abbreviation: MGM)
Manganese activated cerium aluminate, magnesium, zinc [Ce (Mg, Zn) Al ₁₁ O ₁₉ : Mn ²⁺ ] (abbreviation: CMZ)
· Active aluminate, cerium-magnesium with terbium ^{_{[CeMgAl 11 O 19: Tb 3+}} ] ( abbreviation: CAT)
• Europium • Manganese co-activated barium aluminate • Strontium • Magnesium [Ba _{1 -xy} Sr _x Eu _y Mg _{1 -z} Mn _z Al ₁₀ O ₁₇ ] or [Ba _{1 -xy} Sr _x Eu _y Mg _{2 -z} Mn _z Al ₁₆ O ₂₇ ]
Here, x, y and z are numbers satisfying the conditions of 0 ≦ x ≦ 0.4, 0.07 ≦ y ≦ 0.25, and 0.1 ≦ z ≦ 0.6, respectively, and z is 0.4 It is preferable that ≦ x ≦ 0.5.

Examples of such phosphors include europium / manganese co-activated barium aluminate / magnesium [BaMg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ , Mn ²⁺ ], [BaMgAl ₁₀ O ₁₇ : Eu ²⁺ , Mn ^{2]. +} ] (Abbreviation: BAM-G), europium / manganese co-activated barium aluminate / strontium / magnesium [(Ba, Sr) Mg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ , Mn ²⁺ ], [(Ba, Sr) MgAl ₁₀ O ₁₇ : Eu ²⁺ , Mn ²⁺ ] (abbreviation: SBAM-G).

(C) Red • Europium activated phosphorus • Yttrium vanadate [Y (P, V) O ₄ : Eu ³⁺ ] (abbreviation: YPV)
Europium activated yttrium vanadate [YVO ₄ : Eu ³⁺ ] (abbreviation: YVO)
・ Europium-activated yttrium oxysulfide [Y ₂ O ₂ S: Eu ³⁺ ] (abbreviation: YOS)
Manganese-activated magnesium fluoride germanate [3.5MgO.0.5MgF ₂ .GeO ₂ : Mn ⁴⁺ ] (abbreviation: MFG)
Dysprosium-activated yttrium vanadate [YVO ₄ : Dy ³⁺ ] (red and green two-component phosphor, abbreviation: YDS)
In addition, you may mix and use the fluorescent substance of a different compound with respect to one type of luminescent color. For example, only BAM-B (absorbs 313 [nm]) in blue, LAP (does not absorb 313 [nm]) in green, BAM-G (absorbs 313 [nm]) in green, and YOX in red Alternatively, a phosphor of YVO (absorbs 313 [nm]) may be used. In such a case, as described above, the phosphor that absorbs the wavelength 313 [nm] is adjusted so that the total weight composition ratio is larger than 50%, so that the ultraviolet rays almost leak out of the glass bulb. Can be prevented. Therefore, when the phosphor layer 104 includes a phosphor that absorbs ultraviolet rays of 313 [nm], deterioration due to ultraviolet rays such as a diffusion plate made of polycarbonate (PC) that closes the opening of the backlight unit is suppressed, The characteristics as a backlight unit can be maintained for a long time.

  Here, “absorbing ultraviolet rays of 313 [nm]” means an excitation wavelength spectrum near 254 [nm] (excitation wavelength spectrum means excitation light emission while changing the wavelength of the phosphor, and the excitation wavelength and emission intensity are changed. The intensity of the excitation wavelength spectrum at 313 [nm] is defined as 80 [%] or more. That is, the phosphor that absorbs ultraviolet rays of 313 [nm] is a phosphor that can absorb ultraviolet rays of 313 [nm] and convert it into visible light.

(2) High color reproduction Liquid crystal display devices typified by liquid crystal color televisions have been used as a light source for a backlight unit of the liquid crystal display device in accordance with the recent high color reproduction that has been made as part of higher image quality. There is a need to expand the reproducible chromaticity range in cathode discharge lamps and external electrode discharge lamps.

  In response to such a request, for example, by using the following phosphor, the chromaticity range can be expanded as compared with the case of using the phosphor in the embodiment. Specifically, in the CIE 1931 chromaticity diagram, the chromaticity coordinate value of the phosphor for high color reproduction includes a triangle formed by connecting the chromaticity coordinate values of the three phosphors used in the embodiment. Located at the coordinates that expand the reproduction range.

(A) Blue • Europium-activated strontium chloroapatite [Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺ ] (abbreviation: SCA), chromaticity coordinates: x = 0.151, y = 0.065
In addition to the above, europium activated strontium, calcium, barium, chloroapatite [(Sr, Ca, Ba) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺ ] (abbreviation: SBCA) can also be used, and the wavelength 313 (nm) SBAM-B, which can absorb ultraviolet rays), can also be used for high color reproduction.

(B) Green BAM-G, chromaticity coordinates: x = 0.139, y = 0.574
CMZ, chromaticity coordinates: x = 0.164, y = 0.722
CAT, chromaticity coordinates: x = 0.267, y = 0.663
As described above, these can also absorb ultraviolet rays having a wavelength of 313 [nm], and in addition to the three phosphor particles described here, MGM can also be used for high color reproduction.

(C) Red • YOS, chromaticity coordinates: x = 0.651, y = 0.344
YPV, chromaticity coordinates: x = 0.658, y = 0.333
MFG, chromaticity coordinates: x = 0.711, y = 0.287
As described above, these can also absorb ultraviolet rays having a wavelength of 313 [nm], and besides the three phosphor particles described here, YVO and YDS can also be used for high color reproduction.

  In addition, the chromaticity coordinate values shown above are representative values measured only with each phosphor powder, and due to the measurement method (measurement principle), etc., the chromaticity coordinates indicated by each phosphor powder The value may be slightly different from the value listed above. For reference, the chromaticity coordinate values of the phosphor powders of the first embodiment are YOX (x = 0.644, y = 0.353), LAP (x = 0.351, y = 0.585). , BAM-B (x = 0.148, y = 0.56).

  Furthermore, the phosphor used for emitting each color of red, green, and blue is not limited to one type for each wavelength, and a plurality of types may be used in combination.

  Here, the case where a phosphor layer is formed using the above-described phosphor particles for high color reproduction will be described. In this evaluation, there are three evaluations in the case of using a phosphor for high color reproduction based on the area of NTSC triangle (NTSC triangle) connecting the chromaticity coordinate values of the three primary colors of the NTSC standard in the CIE1931 chromaticity diagram. It is performed by a ratio of the area of a triangle formed by connecting chromaticity coordinate values (hereinafter referred to as NTSC ratio).

  For example, when BAM-B is used as blue, BAM-G as green, and YVO as red (Example 1), the NTSC ratio is 92%, and SCA is used as blue, BAM-G as green, and YVO as red. (Example 2) When NTSC ratio is 100%, SCA is used as blue, BAM-G is used as green, and YOX is used as red (Example 3), NTSC ratio is 95%. The luminance can be improved by 10 [%] as compared with the above.

  Note that the chromaticity coordinate values used for the evaluation here are measured in the state of a liquid crystal display device in which a lamp or the like is incorporated, so that the color reproduction range is around the above value depending on the combination with the color filter. there is a possibility.

4). About Filling Gas The rare gas may contain krypton. In this case, infrared radiation of the cold cathode fluorescent lamp can be suppressed. Furthermore, it is preferable that krypton is contained in the rare gas within a range of 0.5 [mol%] to 5 [mol%]. In this case, infrared radiation of the cold cathode fluorescent lamp can be suppressed without greatly changing the lamp voltage. For example, argon is in the range of 0 [mol%] to 9.5 [mol%], neon is in the range of 90 [mol%] to 95.5 [mol%], and krypton is 0.5 [mol%]. ] In the range of 5 [mol%] or less. Furthermore, it is more preferable that krypton is contained in the rare gas within a range of 0.5 [mol%] to 3 [mol%]. Furthermore, it is even more preferable that krypton is contained in the rare gas in the range of 1 [mol%] to 3 [mol%].

5). Regarding the types of lamps In the above embodiments, the cold cathode fluorescent lamp, the internal / external electrode fluorescent lamp, and the hot cathode fluorescent lamp have been mainly described as the low-pressure discharge lamp. It may be an ultraviolet lamp in which no body layer is formed.

  The present invention can be widely applied to low-pressure discharge lamps, lighting devices, and liquid crystal display devices.

Sectional drawing containing the tube axis | shaft of the low pressure discharge lamp which concerns on the 1st Embodiment of this invention (A) Conceptual diagram of oxide film removal process, (b) Cross-sectional view taken along line A-A 'in FIG. 2 (a) The principal part expanded sectional view containing the tube axis | shaft of the low pressure discharge lamp which concerns on the 2nd Embodiment of this invention. Sectional drawing containing the tube axis | shaft of the low voltage | pressure discharge lamp which concerns on the 3rd Embodiment of this invention. Sectional drawing containing the tube axis | shaft of the low pressure discharge lamp which concerns on the 4th Embodiment of this invention. (A) Conceptual diagram of oxide film removal process, (b) Cross-sectional view taken along line A-A 'in FIG. 6 (a) Sectional drawing containing the tube axis | shaft of the modification of the low pressure discharge lamp which concerns on the 4th Embodiment of this invention. The disassembled perspective view of the illuminating device which concerns on the 4th Embodiment of this invention. Partially cutaway perspective view of a lighting apparatus according to a fifth embodiment of the present invention (A) Front view of illumination apparatus according to sixth embodiment of the present invention, (b) Cross-sectional view taken along line A-A ' The perspective view of the image display apparatus which concerns on the 7th Embodiment of this invention. The principal part expanded sectional view containing the tube axis | shaft of the modification 1 of the low voltage | pressure discharge lamp which concerns on the 1st Embodiment of this invention. (A) The principal part expanded sectional view containing the tube axis of the modification 2 of a low-pressure discharge lamp similarly, (b) The principal part expanded sectional view containing the tube axis of the modification 3 of a low-pressure discharge lamp similarly. (A) The principal part expanded sectional view containing the tube axis of the modification 4 of a low-pressure discharge lamp similarly, (b) The principal part expanded sectional view containing the tube axis of the modification 5 of a low-pressure discharge lamp similarly. (A) The principal part expanded front view of the modification 6 of a low-pressure discharge lamp similarly, (b) The principal part expanded sectional view which also contains a tube axis. Sectional view including the tube axis of a conventional low-pressure discharge lamp

100, 118, 120, 122, 124, 126, 128, 200, 300, 400 Low pressure discharge lamp 101 Glass bulb 102, 401 Electrode 103, 402 Lead wire 103a Internal lead wire 103b External lead wire 106 Oxide film 500, 600, 700 Lighting device

Claims (8)

In a low pressure discharge lamp comprising a glass bulb, an electrode disposed inside the glass bulb, a lead wire having one end connected to the electrode and the other end led out of the glass bulb,
A low-pressure discharge lamp characterized in that an oxide film is formed in a portion of the surface of the lead wire that is located outside the glass bulb and in the vicinity of the end of the glass bulb. 2. The low-pressure discharge lamp according to claim 1, wherein a length of the oxide film in a tube axis direction of the low-pressure discharge lamp is in a range of 0.1 [mm] to 2.0 [mm]. . 2. The low pressure according to claim 1, wherein a portion of the surface of the lead wire that is located outside the glass bulb and an end opposite to the glass bulb is covered with solder. Discharge lamp. 3. The low pressure according to claim 1, wherein a thermal expansion coefficient of the glass bulb is in a range of 3.0 × 10 ⁻⁶ [K] to 10.0 × 10 ⁻⁶ [K]. Discharge lamp. The glass used for the glass bulb has an oxide conversion of SiO ₂ of 60 [wt%] to 75 [wt]%, Al ₂ O ₃ of 1 [wt%] to 5 [wt%], and B ₂ O ₃ of 0 [wt%] ~3 [wt %], Li 2 O is 0 [wt%] ~3 [wt %], K 2 O is 3 [wt%] ~11 [wt %], Na 2 O is 3 [ wt%] to 10 [wt%], CaO from 0 [wt%] to 9 [wt%], MgO from 0 [wt%] to 9 [wt%], SrO from 0 [wt%] to 12 [wt%] The low-pressure discharge lamp according to any one of claims 1 to 4, wherein BaO has a composition of 0 wt% to 11 wt%. The lead wire consists of a connection between an internal lead wire and an external lead wire,
6. The internal lead wire has one end connected to the electrode and the other end connected to one end of the external lead near the outer end of the glass bulb. The low-pressure discharge lamp according to any one of the above. An illumination apparatus comprising the low-pressure discharge lamp according to any one of claims 1 to 6. An image display device comprising the illumination device according to claim 7.

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