JP4735673B2 - Mercury emitter and method of manufacturing discharge lamp - Google Patents

Description

  The present invention relates to a mercury emitter, and more particularly to a mercury emitter for introducing mercury into a discharge lamp. The present invention also relates to a method for manufacturing a discharge lamp.

  Conventionally, when mercury is filled into a light-emitting tube (bulb) such as a cold cathode fluorescent lamp for backlight, liquid free mercury is automatically weighed using a mercury reeder, and this is filled into the bulb from the exhaust tube. (For example, refer to Patent Document 1). However, with such means, it has been difficult to accurately measure mercury when the amount of mercury to be sealed is small. Under such circumstances, in recent years, mercury filling bodies in which mercury is reacted are used when filling with mercury.

  This mercury emitter is placed in a glass tube serving as an arc tube and heated by high frequency heating from the outside to release mercury. At this time, iron that does not form an alloy with mercury is used as a heat source that generates heat by high-frequency heating from the outside. Specifically, as shown in FIG. 1, there is a mercury emitter 1000 in which titanium and iron are mixed and sintered and then reacted with mercury.

As another mercury emitter 2000 as shown in FIG. 2A, there is one in which an alloy 110 of titanium and mercury is held in a container 120 formed of an iron thin plate (see, for example, Patent Document 2). The container 120 is provided with a slit portion 130 for preventing bursting.
JP-A-5-121044 JP 2006-128142 A

  However, the mercury emitter 1000 has a problem of poor mercury emission efficiency. In the case of the mercury emitter 1000, since a sintered body of titanium and iron is used as a medium for reacting mercury, when the mercury is released by high frequency heating, the heat source iron is the mercury emitter 1000. This is considered to be because the mercury emitter 1000 cannot be heated uniformly as a whole because it is scattered randomly in the inside.

  On the other hand, the mercury emitter 2000 has a problem that sufficient mercury emission efficiency cannot be obtained. In this case, since the alloy 110 of titanium and mercury is covered with the iron thin plate 120, when the mercury is released by heating, the mercury can be emitted only from a portion of the alloy 110 exposed from the container 120. This is probably because of this.

  Therefore, when manufacturing a fluorescent lamp using the mercury emitter 1000 or 2000 having a low mercury emission efficiency, it is necessary to cause the mercury emitter 1000 or 2000 to react with an excessive amount of mercury. Since mercury is a harmful substance, it is not environmentally preferable to use excessive mercury.

  In addition, in the case of the mercury emitter 2000, as shown in FIG. 2B, mercury is easily released from the portion 110a of the alloy 110 exposed from the end 120a of the thin plate 120 (see region 111). Mercury emission from the central portion (or central portion) 110b of the alloy 110 located outside the end of the thin plate 120 is poor (see region 112). And the mercury which remained in the center part 110b may vaporize at a stretch with heating, and the thin plate 120 may burst. The rupture of the thin plate 120 poses a serious problem in lamp manufacturing because the mercury introduction step stops and also breaks the glass constituting the lamp.

  This invention is made | formed in view of this point, The main objective is to provide the mercury emission body which can introduce | transduce mercury stably while improving the discharge | release efficiency of mercury.

  The mercury emitter according to the present invention includes a mercury emitting part made of tin amalgam containing mercury and tin, and an inclusion part that covers an outer surface of the mercury emitting part, and the inclusion part is made of metal plating Has been.

  In a preferred embodiment, the inclusion part covers the entire outer periphery of the mercury emitting part.

  In a preferred embodiment, the metal plating is plating with a material selected from the group consisting of nickel, chromium, copper, and alloys thereof.

  In a preferred embodiment, the metal plating has a thickness of 2 μm or more.

  In a preferred embodiment, the mercury emitter has a substantially spherical shape.

  In a preferred embodiment, the mercury emitter has a polyhedral shape.

  Another mercury emitter according to the present invention is a mercury emitter for introducing mercury into a discharge lamp, a mercury emitter composed of tin amalgam containing mercury and tin, and the mercury emitter Coating means for covering the outer surface, and the coating means is made of a capsule member made of resin or metal, or a coating member made of resin.

  In a preferred embodiment, the mercury emitting part has a substantially spherical shape, and the capsule member is composed of a pair of substantially hemispherical metal parts surrounding the mercury emitting body.

  A method for manufacturing a discharge lamp according to the present invention includes a step of placing the mercury emitter inside a glass tube and a step of heating the mercury emitter.

  According to the mercury emitter of the present invention, since it has a mercury emitting part made of tin amalgam having a relatively low melting point and an inclusion part made of metal plating covering the outer surface of the mercury emitting part, Mercury can be released using a simple heating device, and the mercury emission efficiency can be improved. In addition, it breaks the inclusion part composed of a relatively thin metal plating and releases mercury from the mercury emission part, so that it is possible to prevent the occurrence of rupture when using a thin plate, thus stabilizing the mercury. Can be introduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, components having substantially the same function may be denoted by the same reference numerals for the sake of brevity. In addition, this invention is not limited to the following embodiment.

  FIG. 3 shows an example of a cross-sectional configuration of the mercury emitter 100 according to the embodiment of the present invention. The mercury emitter 100 of this embodiment is used for introducing mercury into a discharge lamp. The mercury emitter 100 shown in FIG. 3 includes a mercury emitter 10 and an inclusion part 20 that covers the outer surface of the mercury emitter 10.

  The mercury discharge part 10 is comprised from the tin amalgam containing mercury (Hg) and tin (Sn). The melting point of tin amalgam constituting this mercury releasing part 10 is 58 to 232 ° C.

  The inclusion part 20 is comprised from metal plating, and is comprised from Ni plating in this embodiment. The thickness T of the inclusion unit 20 is, for example, 2 μm or more. For example, if the thickness is less than 2 μm, it is difficult to ensure the uniformity of plating, and it becomes difficult to obtain the effect of increasing the temperature at which discharge starts, so that it is preferably 2 μm or more, for example. For example, if the thickness exceeds 70 μm, the plating film is broken so as to violently rupture, so that there is a possibility that the lamp is broken or fragments are scattered inside the lamp. Therefore, problems such as contamination inside the lamp occur. In addition, it takes a very long time for plating, which is expensive. Therefore, the thickness (plating thickness) T of the inclusion part 20 is preferably set to 70 μm or less, for example. A more preferable example of the thickness T of the inclusion part 20 is 10 to 40 μm.

  In the configuration of the present embodiment, the inclusion unit 20 covers the entire outer periphery of the mercury release unit 10, thereby preventing the release of tin amalgam having a relatively low melting point at a low temperature. The mercury emitting part 10 in this example has a substantially spherical shape, and its dimension (diameter) is, for example, 1.0 to 2.5 μm. In addition, the mercury discharge | release part 10 or the mercury discharge body 100 is not restricted to a substantially spherical shape, For example, it can also be made into a polyhedron shape. When the mercury emitter 100 has a polyhedral shape, when the mercury emitter 100 is disposed in the glass tube, the mercury emitter can be prevented from rolling and moving in the tube axis direction of the glass tube. There is an advantage that the heating position can be easily positioned.

  As described above, when mercury is released by high frequency heating, in the mercury emitter 1000 shown in FIG. 1, the heating efficiency is high because iron as the heat source is scattered randomly in the mercury emitter 1000. Not good. Furthermore, since the mercury emitter 2000 shown in FIG. 2A has the slit 130 formed in the container 120, at least the effect of the eddy current is reduced by the division of the slit 130, and as a result, the heating efficiency is lowered. . On the other hand, if the slits 130 are not provided in the container 120, the mercury outlet is blocked, and the mercury emission efficiency is reduced accordingly.

  According to the mercury emitter 100 of the present embodiment, when the inclusion 20 that covers the mercury emitter 10 is broken by the pressure of mercury vapor that is emitted from the mercury emitter 10 during heating, mercury is thereby released. Mercury emission efficiency can be improved. Moreover, since the mercury alloy part 10 is covered with the inclusion part 20 which consists of metal plating, discharge | release of mercury can be suppressed until it becomes required temperature, and is convenient. In addition, since the release of mercury from the mercury alloy part 10 can be realized by breaking the inclusion part 20, it is possible to execute the mercury introduction process with an inexpensive heating device. Furthermore, since the thin plate 120 shown in FIG. 2A is not used, the problem of rupture due to overheating can be solved.

  A mercury introduction process using the mercury emitter 100 of the present embodiment will be described with reference to FIGS.

 First, as shown in FIG. 4A, the mercury emitter 100 of the present embodiment is placed in a glass bulb 300. Next, as shown in FIG. 4B, the mercury emitter 100 is heated to generate mercury vapor from the mercury emitting portion 10 made of tin amalgam having a relatively low melting point (see arrow 25). Here, the heating can be performed by high-frequency heating, for example. Further, for this heating, a typical electric furnace, a gas furnace, or a heating means using a burner can be used.

  Next, as shown in FIG. 4C, when the pressure of the mercury vapor 25 from the mercury discharge portion 10 increases, the inclusion portion 20 made of metal plating causes the pressure of the mercury vapor 25 (that is, the internal pressure by the mercury vapor 25). It is broken, thereby introducing mercury into the glass bulb 300 (see arrow 27). Since the inclusion part 20 is broken by the internal pressure of the mercury vapor 25 and mercury is released, it is possible to avoid a problem (for example, surrounding damage, etc.) such as when the mercury emitter 2000 shown in FIG. 2A bursts. it can. Further, in the configuration of the present embodiment, the mercury discharge portion 10 made of tin amalgam having a relatively low melting point becomes mercury vapor in a short time, and therefore, as shown in FIG. Mercury can be introduced (arrow 28). Therefore, the extraction efficiency of the mercury introduction process can be increased.

  After the introduction of mercury by heating is completed and only the inclusion part 20 is obtained, a part of the valve 300 is cut (arrow 29) as shown in FIG. 4E, and then the valve 300 into which mercury has been introduced. Is sealed to seal the operation. In this way, the mercury introduction process can be performed using the mercury emitter 100 of the present embodiment.

  Further, in the mercury emitter 100 of the present embodiment, it is also possible to provide a portion having a thickness smaller than that of other portions on at least a part of the outer surface of the inclusion portion 20. For example, in the example shown in FIG. 5A, a concave portion (or a crack portion) 25 is provided in a part of the inclusion portion 20. FIGS. 5B and 5B are partially enlarged views of the recess 25A and the recess 25B in FIG. 5A, respectively.

  In the concave portion 25 </ b> A shown in FIG. 5B, a V-shaped hole is formed on the outer surface of the inclusion portion 20. Further, in the recess 25 </ b> B shown in FIG. 5C, a hole including a wall surface (or an inclined surface) and a bottom surface is formed on the outer surface of the inclusion unit 20. By forming a portion (recessed portion 25) having a thinner thickness than the other portion on a part of the outer surface of the inclusion portion 20, the inclusion portion is based on the thin portion when the mercury emitter 100 is heated. This is because (metal plating) 20 is torn and mercury can be easily released.

  The thickness of the thin part is, for example, in the range of 10% to 70% based on the thickness of the inclusion part 20 (the thickness of the other part), and 20 [ %] Or more and 50 [%] or less is preferable. Here, the thickness of the thin part (25) refers to the thickness of the thinnest part among the thin parts.

  The form of the thin portion 25 is not limited to the configuration shown in FIG. 5, and a portion 25 </ b> C that is partially flat may be formed as shown in FIG. 6. Further, even though the thickness between the outer surface and the inner surface of the inclusion part 20 is substantially the same as the other parts, as shown in FIGS. By providing the holes 27, it is also possible to construct the thin portion 25D (25). FIG. 7B is an enlarged view of the thin portion 25D shown in FIG. Furthermore, the inclusion part may have a multilayer structure. In this case, all the layers may be made of the same material, or the material may be different for each layer.

  Note that the mercury emitter 100 of the present embodiment can be configured as shown in FIG. In the mercury emitter 100 shown in FIG. 8, the covering means 20 is formed on the outer surface of the mercury emitter 10. In this example, the covering means 20 is made of a resin or metal capsule member. More specifically, the mercury discharge part 10 has a substantially spherical shape, and the capsule member 20 is composed of a pair of substantially hemispherical metal parts (20A, 20B).

  Next, a method for manufacturing a fluorescent lamp (or low-pressure discharge lamp) using the mercury emitter 100 will be described with reference to FIGS.

(Process A)
First, the prepared straight tubular glass tube 300 is dipped in the phosphor suspension 302 in the tank 301 by dropping the lower end portion thereof. The phosphor suspension 302 includes, for example, blue, red, and green phosphor particles. By making the inside of the glass tube 300 have a negative pressure, the phosphor suspension 302 in the tank 301 is sucked up and applied to the inner surface of the glass tube 300. This siphoning is set so that the liquid level becomes a predetermined height of the glass tube 300 by detecting the liquid level with the optical sensor 303. The liquid level error at this time is relatively large because of the influence of the viscosity of the phosphor suspension 302, the surface tension of the liquid level, and the like, and an error of about ± 0.5 [mm] occurs.

(Process B)
Next, the glass tube 300 is opened to the atmosphere, and then the lower end portion of the glass tube 300 is pulled up from the phosphor suspension 302, and the phosphor suspension 302 inside the glass tube 300 is discharged to the outside. As a result, the phosphor suspension is applied in a film form to a predetermined region on the inner periphery of the glass tube 300.

  Subsequently, after drying the phosphor suspension 302 applied in the glass tube 300, a brush or the like 304 is inserted into the inner surface of the glass tube 300 to remove an unnecessary phosphor portion at the end of the glass tube 300. .

  Subsequently, the glass tube 300 is transferred into a heating furnace (not shown) and baked to obtain a phosphor film 305.

(Process C)
Thereafter, the electrode unit 309 including the electrode 306, the bead glass 307, and the lead wire 308 is inserted into one end of the glass tube 300 on which the phosphor film 305 is formed, and then temporarily fixed. Temporary fixing means that the outer peripheral portion of the glass tube 300 where the bead glass 307 is located is heated by the burner 310 and a part of the outer periphery of the bead glass 307 is fixed to the inner peripheral surface of the glass tube 300. Since only a part of the outer periphery of the bead glass 307 is fixed, the air permeability of the glass tube 300 in the tube axis direction is maintained.

(Process D)
Next, the glass tube 300 is turned upside down, and the electrode 311, the bead glass 312, and the lead wire having substantially the same configuration as the electrode unit 309 are placed on the glass tube 300 from the side opposite to the side where the electrode unit 309 is inserted. After inserting the electrode unit 314 containing 313, the outer peripheral part of the glass tube 300 in which the bead glass 312 is located is heated with the burner 315, and the glass tube 300 is sealed and airtightly sealed (first sealing). Further, the error from the set value of the sealing position in the first sealing is about 0.5 [mm].

  In addition, the insertion position of the electrode unit 309 in the process C and the insertion of the electrode unit 314 in the process D are different in the length of the absence region of the phosphor layer 405 extending from both ends of the glass bulb 402 after sealing, which will be described later. It is preferable that the amount of insertion is adjusted so as to be in such a position.

  In this case, the electrode unit 314 on the other end side is inserted deeper than the position overlapping the phosphor film 305 compared to the electrode unit 309 on the one end side. The reason why such a configuration is suitable is as follows. That is, there is often a difference in the thickness of the phosphor layer 405 between one end and the other end of the lamp, and when a plurality of lamps are installed in an illumination device such as a backlight unit in the same direction, illumination is performed. Luminance unevenness occurs as a whole device. In order to prevent this, for example, it can be considered that one end and the other end of the lamp are alternately incorporated in the lighting device.

  This is because one end and the other end of the lamp can be automatically and easily identified using a sensor or the like. If an image sensor of 2 million [pixels] is used as the sensor, 1 [pixel] can be set to 0.1 [mm], so that measurement accuracy in units of 0.1 [mm] can be realized.

  Considering these circumstances, if the difference in the length of the non-existing region of the phosphor layer 404 is at least 2 [mm] between the one end side and the other end side of the glass bulb 401, the sensor is surely Can be used to identify the longitudinal orientation.

  In addition, if the difference in the length of the non-existence region of the phosphor layer 404 is at least 3 [mm] between the one end side and the other end side of the glass bulb 401, it is possible to more reliably use the sensor in the longitudinal direction. Can be identified. In this case, the image sensor may have a measurement accuracy in units of 0.5 [mm]. Moreover, the upper limit of the difference in length is, for example, about 8 [mm]. This is because if it is larger than 8 [mm], the non-existing region of the phosphor layer 404 that does not contribute to light emission becomes long, and it becomes difficult to secure an effective light emission length.

(Process E)
Subsequently, a portion of the glass tube 300 between the electrode unit 309 and the end of the glass tube 300 closer to the electrode unit 309 is heated by the burner 316 to reduce the diameter, thereby forming a constricted portion 300a. . Thereafter, the mercury emitter 100 according to the present embodiment is put into the glass tube 300 from the end portion and is hooked on the constricted portion 300a.

(Process F)
Subsequently, exhaust in the glass tube 300 and filling of the sealed gas into the glass tube 300 are sequentially performed. Specifically, the head of the air supply / exhaust device (not shown) is attached to the end of the glass tube 300 on the mercury emitter 100 side, and first, the inside of the glass tube 300 is evacuated to a vacuum, and the heating device (FIG. The entire glass tube 300 is heated from the outer periphery by not shown). Thereby, the impure gas in the glass tube 300 including the impure gas entering the phosphor film 305 is discharged. After the heating is stopped, a predetermined amount of sealed gas (for example, a mixed rare gas such as a mixed gas having a partial pressure ratio of argon: 95 [%], neon: 5 [%], etc.) is filled.

(Process G)
When the filled gas is filled, the end of the glass tube 300 on the mercury emitter 100 side is heated by the burner 317 and sealed.

(Process H)
Subsequently, in a process H shown in FIG. 10, the mercury emitter 100 is induction-heated by a high frequency oscillation coil (not shown) arranged around the glass tube 300 to release mercury from the mercury emitter 100 (mercury extraction process). ). In the mercury emitter 100 of the present embodiment, since the mercury emitter 10 is made of tin amalgam having a relatively low melting point, this heating completes mercury emission in a short time. When the mercury emitting part 10 is completely eliminated, the inclusion part 20 remains only in the mercury emitting body 100.

  As a method for heating the mercury emitter 100, various known methods such as light heating can be used. Thereafter, the glass tube 300 is heated in the heating furnace 318, and the released mercury is moved toward the electrode 311 of the electrode unit 314.

(Process I)
Next, the outer peripheral part of the glass tube 300 where the bead glass 307 is located is heated by a burner 319, and the glass tube 300 is sealed and hermetically sealed. The error from the set value of the sealing position of the one end is about ± 0.5 [mm] as in the other end.

(Process J)
Subsequently, in the glass tube 300, the end part on the mercury emitter (inclusion part 20) side is separated from the sealing part at the one end part. This completes the fluorescent lamp (or low-pressure discharge lamp).

  As described above, according to the configuration of the manufacturing method of the low-pressure discharge lamp according to the present embodiment, the mercury emitter 100 having a high mercury emission efficiency is used, so that the amount of mercury reacted with the mercury emitter 100 can be reduced. In other words, the amount of mercury used for the lamp can be reduced, and the environmental load can be reduced.

  Next, the backlight unit 600 according to the present embodiment will be described with reference to FIG. FIG. 11 is an exploded perspective view of the backlight unit 600 of the present embodiment.

  The backlight unit 600 of the present embodiment is a direct type, and includes a rectangular parallelepiped housing 601 having one open face, a plurality of lamps 400 housed in the housing 601, and a lighting circuit ( A pair of sockets 602 for electrical connection to an unillustrated) and optical sheets 603 covering the opening of the housing 601 are provided. The lamp 400 is manufactured using the manufacturing method of the present embodiment.

  Next, the low-pressure discharge lamp 400 of the present embodiment (hereinafter simply referred to as “lamp 400”) will be briefly described. The lamp 400 is a cold cathode fluorescent lamp. In this example, the mercury emitter 100 (or the inclusion unit 20) does not exist inside the lamp 400 and has already been removed.

  The lamp 400 of the present embodiment includes a glass bulb, an electrode disposed in the glass bulb, and a lead wire 404 extending from the electrode. The glass bulb has a straight tube shape and has a substantially circular cross section cut perpendicular to the tube axis. This glass bulb has, for example, an outer diameter of 3.0 [mm], an inner diameter of 2.0 [mm], and a total length of 750 [mm], and the material thereof is borosilicate glass.

  The dimensions of the lamp 400 of the present embodiment are values corresponding to the dimensions of the glass bulb 402 having an outer diameter of 3.0 [mm] and an inner diameter of 2.0 [mm]. In the case of a cold cathode fluorescent lamp, the inner diameter is in the range of 1.4 [mm] to 7.0 [mm], and the wall thickness is in the range of 0.2 [mm] to 0.6 [mm], It is preferable that the total length is 1500 [mm] or less. These values are examples and are not limited to these.

  Mercury is sealed inside the glass bulb at a predetermined ratio with respect to the volume of the glass bulb, for example, 0.6 [mg / cc], and a rare gas such as argon or neon is sealed at a predetermined sealing pressure, for example, 60 It is enclosed with [Torr]. As the rare gas, a mixed gas having a partial pressure ratio of argon and neon (Ar = 5 [%], Ne = 95 [%]) is used.

A phosphor layer is formed on the inner surface of the glass bulb. The phosphor particles used for the phosphor layer are, for example, red phosphor particles (Y ₂ O: Eu ³⁺ ), green phosphor particles (LaPO ₄ : Ce ³⁺ , Tb ³⁺ ), and blue phosphor particles (BaMg ₂ Al ₁₆ O). ₂₇ : Eu ²⁺ ). A protective film (not shown) of a metal oxide such as yttrium oxide (Y ₂ O ₃ ) may be provided between the inner surface of the glass bulb and the phosphor layer.

  Furthermore, lead wires 404b are led out from both ends of the glass bulb. The lead wires 404b are sealed at both ends of the glass bulb via bead glass. The lead wire 404b is, for example, a joint consisting of an internal lead wire (not shown) made of tungsten and an external lead wire (404b in FIG. 11) made of nickel. The wire diameter of the internal lead wire is 1 [mm], the total length is 3 [mm], the wire diameter of the external lead wire is 0.8 [mm], and the total length is 5 [mm]. Further, a hollow type, for example, a bottomed cylindrical electrode is fixed to the tip of the internal lead wire. This fixing is performed using, for example, laser welding.

  The fluorescent lamp manufactured by the manufacturing method of the present embodiment is not limited to a cold cathode fluorescent lamp, and may be a hot cathode fluorescent lamp.

  Next, peripheral members such as the housing 601 will be described. The housing 601 is made of, for example, polyethylene terephthalate (PET) resin, and a reflective surface 604 is formed by depositing a metal such as silver on the inner surface thereof. In addition, as a material of the housing | casing 601, you may comprise by metal materials, such as materials other than resin, for example, aluminum, a cold rolled material (for example, SPCC). Further, as the reflection surface 604 on the inner surface, other than the metal vapor-deposited film, for example, a reflection sheet whose reflectance is increased by adding calcium carbonate, titanium dioxide or the like to polyethylene terephthalate (PET) resin is used. May be.

  Inside the housing 601, a socket 602, an insulator 605, and a cover 606 are disposed. Specifically, the sockets 602 are provided at predetermined intervals in the lateral direction (vertical direction) of the housing 601 corresponding to the arrangement of the lamps 400. The socket 602 is obtained by processing a plate material made of stainless steel or phosphor bronze, for example, and has a fitting portion 602a into which the external lead wire 404b is fitted. Then, the external lead wire 404b is elastically deformed and fitted so as to expand the fitting portion 602a. As a result, the external lead wire 404b fitted into the fitting portion 602a is pressed by the restoring force of the fitting portion 602a and is difficult to come off. Thereby, the external lead wire 404b can be easily fitted into the fitting portion 602a, but can be made difficult to come off.

  The socket 602 is covered with an insulator 605 so as not to short-circuit between adjacent sockets 602. The insulator 605 is made of, for example, polyethylene terephthalate (PET) resin. Note that the insulator 605 is not limited to the above structure. Since the socket 602 is in the vicinity of the internal electrode 403 that becomes relatively high during the operation of the lamp 400, the insulator 605 is preferably made of a heat-resistant material. As a material for the heat-resistant insulator 605, for example, polycarbonate (PC) resin, silicon rubber, or the like can be used.

  A lamp holder 607 may be provided inside the housing 601 at a place where necessary. The lamp holder 607 that fixes the position of the lamp 400 inside the housing 601 is, for example, polycarbonate (PC) resin, and has a shape that conforms to the outer shape of the lamp 400. The “place as needed” means that the lamp 400 is bent when the lamp 400 is long, for example, exceeding a total length of 600 [mm], such as near the central portion in the longitudinal direction of the lamp 400. It is a place necessary to eliminate.

  The cover 606 divides the socket 602 and the space inside the housing 601 and is made of, for example, polycarbonate (PC) resin, keeps the periphery of the socket 602 warm, and highly reflects at least the surface on the housing 601 side. Therefore, a reduction in luminance at the end of the lamp 400 can be reduced.

  The opening of the housing 601 is covered with a light-transmitting optical sheet 603 and is sealed so that foreign matters such as dust and dust do not enter inside. The optical sheet 603 is formed by laminating a diffusion plate 608, a diffusion sheet 609, and a lens sheet 610.

  The diffusion plate 608 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 601. The diffusion sheet 609 is made of, for example, a polyester resin. The lens sheet 610 is, for example, a laminate of an acrylic resin and a polyester resin. These optical sheets 603 are arranged so as to be sequentially superimposed on the diffusion plate 608.

  Note that the backlight unit of the present embodiment is not limited to the direct type, but may be an edge light type as shown in FIG. The backlight unit shown in FIG. 12 includes a reflector 701, a lamp 400, a socket (not shown), a light guide plate 702, a diffusion sheet 703, and a prism sheet 704.

  The reflection plate 701 is disposed so as to surround the periphery of the light guide plate 702 except for the liquid crystal panel side (arrow Q), and the side surface covering the bottom surface portion 701b covering the bottom surface and the side surface excluding the side where the lamp 400 is disposed. 701a and a curved lamp side surface portion 701c covering the periphery of the lamp 400, and reflects light emitted from the lamp from the light guide plate 702 to the liquid crystal panel (not shown) side (arrow Q). . Further, the reflecting plate 701 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 602 used in the backlight unit 600 according to the fifth embodiment of the present invention. In FIG. 21, the end of the lamp 400 is omitted for convenience of illustration.

  The light guide plate 702 is for guiding the light reflected by the reflection plate to the liquid crystal panel side. The light guide plate 702 is made of, for example, translucent plastic, and is stacked on the reflection plate 701a provided on the bottom surface of the backlight unit 700. It is weighted. As a material, polycarbonate (PC) resin or cycloolefin-based resin (COP) can be applied.

  The diffusion sheet 703 is for expanding the visual field, and is made of a film having a diffusion transmission function made of, for example, polyethylene terephthalate resin or polyester resin, and is stacked on the light guide plate 702.

  The prism sheet 704 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 703. A diffusion plate may be further laminated on the prism sheet 704.

  In the present embodiment, a reflective sheet (not shown) is provided on the outer surface of the glass bulb 402 except for a part in the circumferential direction of the lamp 400 (on the light guide plate 702 side when inserted into the backlight unit 700). Aperture type lamps may also be used.

  Furthermore, the backlight unit of the present embodiment is used by being incorporated in the liquid crystal display device 800. FIG. 13 shows an outline of the liquid crystal display device according to this embodiment.

  As shown in FIG. 13, the liquid crystal display device 800 is, for example, a television of 32 [inch] or more, and includes a liquid crystal screen unit 801 including a liquid crystal panel and the like, a backlight unit 600 of this embodiment, and a lighting circuit 802. Prepare.

  The liquid crystal screen unit 801 is a typical 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 400 inside the backlight unit 600. The lamp 400 is operated at a lighting frequency of 40 [kHz] to 100 [kHz] and a lamp current of 3.0 [mA] to 25 [mA].

  Although FIG. 13 illustrates the case where the lamp 400 of this embodiment is inserted into the direct-type backlight unit 600 as the light source device of the liquid crystal display device 800, the present invention is not limited to this.

  As mentioned above, although this invention was demonstrated by suitable embodiment, such description is not a limitation matter and of course various modifications are possible.

  According to the present invention, it is possible to provide a mercury emitter capable of improving mercury emission efficiency and stably introducing mercury.

Perspective view of conventional mercury emitter 1000 Perspective view of conventional mercury emitter 2000 Cross section of mercury emitter 2000 Sectional drawing which shows the structure of the mercury emitter 100 which concerns on embodiment of this invention. (A) to (e) are process cross-sectional views for explaining a method of using the mercury emitter 100 according to the embodiment of the present invention. (A) is sectional drawing which shows the modification of the mercury discharge body 100 which concerns on embodiment of this invention, (b) and (c) are the elements on larger scale in (a), respectively. Sectional drawing which shows the modification of the mercury emitter 100 which concerns on embodiment of this invention (A) is sectional drawing which shows the modification of the mercury emitter 100 which concerns on embodiment of this invention, (b) is the elements on larger scale in (a). Sectional drawing which shows the modification of the mercury emitter 100 which concerns on embodiment of this invention The conceptual diagram to process AG of the manufacturing method of the low pressure discharge lamp which concerns on embodiment of this invention. The conceptual diagram to process HJ of the manufacturing method of the low pressure discharge lamp which concerns on embodiment of this invention. The disassembled perspective view which shows typically the structure of the backlight 600 which concerns on embodiment of this invention. The perspective view which shows typically the structure of the backlight 700 which concerns on embodiment of this invention. The perspective view of the liquid crystal display device 800 which concerns on embodiment of this invention.

Explanation of symbols

10 Mercury emission part 20 Inclusion part 25 Thin part (concave part)
29 Air gap 100 Mercury emitter 300 Glass bulb 400 Lamp (low pressure discharge lamp)
600 Backlight 800 Liquid crystal display device 1000, 2000 Mercury emitter

Claims (5)

A mercury emission part composed of tin amalgam containing mercury and tin;
An inclusion part covering the outer surface of the mercury emitting part,
The mercury emitting body, wherein the inclusion part is made of metal plating.   The mercury emitter according to claim 1, wherein the inclusion part covers the entire outer periphery of the mercury emitting part.   The mercury emitting body according to claim 1 or 2, wherein the metal plating is plating with a material selected from the group consisting of nickel, chromium, copper and alloys thereof.   The mercury emitting body according to any one of claims 1 to 3, wherein the metal plating has a thickness of 2 µm or more. A method for manufacturing a discharge lamp, comprising: a step of arranging the mercury emitter according to any one of claims 1 to 4 inside a glass tube; and a step of heating the mercury emitter.

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