JP2008135362A - Socket, lamp provided with socket, backlight unit and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a socket which can make an automation of an assembly work of a lamp into a backlight unit and can prevent a crack at a lead wire sealing portion of the lamp during the work. <P>SOLUTION: The socket 8, in which a lamp 5 having a glass bulb 7 and a lead wire 6 extruded from an end portion of the glass bulb 7 are fixed, is provided with a holding portion 9 to hold the glass bulb 7 and a connecting portion 10 contacting with the lead wire 6 while the glass bulb 7 is held in the holding portion 9. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a socket, a lamp with a socket using the socket, a backlight unit, and a liquid crystal display device.

  2. Description of the Related Art Conventionally, a lamp (cold cathode fluorescent lamp) used as a backlight of a liquid crystal display device has a glass bulb and a lead wire protruding from the end of the glass bulb. Connected to. The operation of assembling the lamp into the backlight unit is being automated, and accordingly, it is required to make the socket to which the lamp is attached compatible with automation. Accordingly, as such a socket, as shown in FIG. 24, there is one made of a metal piece having a groove portion 1a bent in a substantially V shape so that a lead wire can be sandwiched.

  However, when such a socket 1 is used, when a lead wire is inserted into the groove 1a of the socket 1, a load is applied to the sealing portion of the glass bulb to which the lead wire is sealed, which may cause damage.

Then, as shown in FIG. 25, when attaching the lamp | ramp 5 to the socket 1, the connector apparatus 2 aiming at relieving the load to the said sealing part is proposed (for example, refer patent document 1 etc.). The connector device 2 includes a main body 3 and an actuator 4. The main body 3 includes two contact portions 3a that are in electrical contact with the lead wires 6 of the lamp 5, an operating piece 3b that opens and closes the contact portions 3a, and a seat 3c on which the tube end of the glass bulb 7 is placed. The actuator 4 serves as a cover for the main body 3. First, the actuator 4 is in an open state as shown in FIG. 25. At this time, the cam portion 4a provided inside the actuator 4 is interposed between the operating pieces 3b of the main body, so that the main body The contact portion 3a is open. Therefore, the tube end of the glass bulb 7 can be placed on the seat 3c while the lead wire 6 of the lamp 5 is disposed between the two contact portions 3a. Thereafter, when the actuator 4 is closed, the cam portion 4a is disengaged from between the operating pieces 3b, and both contact portions 3a are closed. By this action, the lead wire 6 is sandwiched and fixed between the two contact portions 3a.
JP 2005-259370 A

  However, when such a connector device 2 is used, not only does the work of closing the actuator 4 occur after the work of placing the lead wire 6 between the two contact portions 3a, it takes work time, Since the actuator 4 is a very small component, it has been difficult to automate a series of operations involving the operation of closing the actuator 4.

  Further, in the connector device 2, since the lamp 5 is fixed to the connector device 2 by sandwiching only the lead wire 6 of the lamp 5, if the lamp 5 is bent when the backlight unit is assembled or moved. A load may be applied to the sealing portion of the lamp 5 to cause a crack.

  Moreover, since the main body 3 and the actuator 4 are composed of different complex parts, it takes time to manufacture the connector device 2.

  Therefore, the present invention provides a socket that can automate the work of assembling the lamp into the backlight unit and can prevent cracks from occurring in the lead wire sealing portion of the lamp during the work. With the goal.

  It is another object of the present invention to provide a lamp with a socket that can prevent cracks from occurring at the lead wire sealing portion of the bulb during the operation of attaching the socket to the glass bulb.

  Another object of the backlight unit and the liquid crystal display device according to the present invention is to realize high reliability against cracks in the lead wire sealing portion of the lamp.

  In order to solve the above problems, a socket according to the present invention is a socket to which a lamp having a glass bulb and a lead wire protruding from an end portion of the glass bulb is mounted, and a holding portion for holding the glass bulb And a connecting portion in contact with the lead wire in a state where the glass bulb is held by the holding portion.

  Further, in the socket according to the present invention, the holding portion has a pair of holding and holding pieces for holding the glass bulb, and the holding and holding pieces are temporarily expanded when the glass bulb is inserted. The glass bulb is closed after the glass bulb is inserted, and the glass bulb is held, and the connecting portion has a connecting pinching piece to which the lead wire is pinched and connected, and is synchronized with opening and closing of the holding pinching piece. It is preferable to open and close.

  The lamp with a socket according to the present invention is a lamp with a socket having a glass bulb and a lead wire protruding from an end portion of the glass bulb, and the socket is mounted on both end portions. Is held by the holding portion, and the lead wire is in contact with the contact portion.

  The backlight unit according to the present invention includes a lamp and a socket to which the lamp is attached and connected to a lighting circuit.

  Furthermore, the backlight unit according to the present invention includes the lamp with a socket.

  Furthermore, the liquid crystal display device according to the present invention includes the backlight unit.

  The socket according to the present invention provides a socket that can automate the work of assembling the lamp into the backlight unit and can prevent cracks from occurring in the lead wire sealing portion of the lamp during the work. be able to.

  Moreover, the present invention can prevent cracks from occurring in the lead wire sealing portion of the glass bulb in the operation of attaching the socket to the glass bulb in the lamp with socket.

  In addition, the backlight unit and the liquid crystal display device according to the present invention can achieve high reliability against cracks in the lead wire sealing portion of the lamp.

(First embodiment)
FIG. 1 is a perspective view of a socket according to the first embodiment of the present invention. FIG. 2 shows an enlarged front view of a main part in a state where the lamp 5 is assembled in the socket 8, and FIG. 3 shows a left side view thereof.

  As shown in FIG. 1, the socket 8 is formed by bending a sheet of a copper alloy such as phosphor bronze, brass, or white or an alloy of iron and nickel. 5 includes a holding portion 9 that holds the glass bulb 7 and a connecting portion 10 that contacts a lead wire 6 of the lamp 5 described later.

  The holding part 9 is comprised from a pair of clamping piece 9a as shown in FIG. 1, and each clamping piece 9a is connected in the lower end part. And the holding | maintenance part 9 plays the role which hold | maintains the glass bulb | bulb 7 of the lamp | ramp 5 by the spring effect | action of the clamping piece 9a. The holding part 9 has an arc shape adapted to the shape and dimensions of the glass bulb 7 so that the glass bulb 7 of the lamp 5 can be stably held between the pair of clamping pieces 9a. Moreover, the insertion part 9b located in the upper end part of the clamping piece 9a is bent about 1 [mm] outward so that the glass bulb 7 of the lamp 5 can be easily inserted. It should be noted that the inner maximum distance P between the holding pieces 9 a of the holding portion 9 in a state where the lamp 5 is not inserted may be appropriately used that is slightly smaller than the outer diameter of the glass bulb 7 of the lamp 5. For example, when a glass bulb 7 having an outer diameter of 4 [mm] is used, P may be about 3.5 [mm].

  In this case, the length N of the lamp 5 in the longitudinal direction of the holding portion 9 is, for example, 8 [mm].

  Although the holding part 9 shown in FIGS. 1-3 is comprised by a pair of clamping piece 9a, you may be comprised by 2 or more pairs of clamping pieces, for example. In this case, since the glass bulb 7 is held at two or more locations near the tube end of the glass bulb 7, the stability of holding the lamp 5 is further increased.

  As shown in FIGS. 2 and 3, the connecting portion 10 has a thin plate shape, and one end thereof is in contact with the lead wire 6 of the lamp 5, and serves to electrically connect to the lamp 5. Plays. And the lower end part of the holding | maintenance part 9 is connected via the other end part of this connection part 10. FIG. For example, the plate-like connection portion 10 extends obliquely upward from the lower end portion of the holding portion 9 so as to avoid the glass bulb 7 and contact the lead wire. Moreover, the front-end | tip part of this connection part 10 is bend | folded in the substantially reverse direction with respect to the extending direction, and the bending part is formed. And the groove part 10a cut into the V shape at this bending part is provided. Since the cross section of the lead wire 6 cut perpendicularly to the line axis has a substantially circular shape, the contact area with the connection portion 10 is increased by placing the lead wire 6 on the groove portion 10a, and the electrical connection is stable. To do. The height of the groove portion 10a with respect to the other end of the connecting portion 10 is the height of the lead wire 6 in the state in which the glass bulb 7 of the lamp 5 is incorporated in the holding portion 9 (the other end of the connecting portion 10 is the reference). It is preferable to set a little higher than the above. Thereby, the force of the spring action of the connection part 10 is added to the contact of the lead wire 6 and the connection part 10, and the contact can be stabilized.

  The socket according to the first embodiment of the present invention can automate the work of assembling the lamp 5 into the backlight unit with the above-described configuration, and the lead wire 6 sealing portion of the lamp 5 is cracked during the work. Can be prevented. Further, since the lamp 5 is substantially held by sandwiching the glass bulb 7 between the sandwiching pieces 9 a, no load is applied to the sealed portion of the lead wire 6 of the lamp 5 after being assembled into the socket 8. I'm sorry.

  Here, in forming the groove portion 10a, instead of performing a substantially V-shaped cutting process, the connecting portion 12 is folded in the longitudinal direction like the socket 11 shown in FIG. 4 and cut perpendicularly to the longitudinal direction. The cross section may be substantially V-shaped. In this case, the contact angle between the lead wire 6 and the connecting portion 12 is further increased by setting the bending angle of the tip portion of the connecting portion 12 so that the tip portion is parallel to the lead wire 6, and the electrical Connection can be further stabilized.

  Moreover, the structure of the holding | maintenance part 9 and the connection part 10 is not limited to what processed one board | plate material, For example, it is comprised, for example by another raw material, for example, may be integrated by welding etc. . When the lamp 5 is a cold cathode fluorescent lamp employing a hollow electrode, the portion where the holding portion 9 is in contact with the glass bulb 7 is a region where the electrode of the lamp 5 exists. When the lamp current value is small and the holding unit 9 is made of a material having a high thermal conductivity, the temperature near the electrode of the lamp 5 is reduced by the heat radiation effect of the holding unit 9 during lighting. It may be lower than In this case, since the mercury enclosed in the lamp 5 has a characteristic of moving to a lower temperature, the mercury is concentrated near the electrode of the lamp 5 and the brightness of the lamp 5 is lowered. Therefore, by forming at least a portion of the holding portion 9 in contact with the glass bulb 7 with a material having low thermal conductivity (such as nickel when the other portion is copper), the heat dissipation effect is suppressed and the luminance of the lamp 5 is reduced. A decrease can be prevented. On the contrary, when the lamp current value is large, the temperature in the vicinity of the electrode of the lamp 5 becomes too high, a large amount of spatter occurs, and mercury is consumed by the sputtered material, resulting in a decrease in luminance maintenance rate. There is. Therefore, by forming at least a portion of the holding portion 9 in contact with the glass bulb 7 with a material having high thermal conductivity (such as copper when the other portion is nickel), the heat dissipation effect near the electrode of the lamp 5 can be obtained. By increasing it, it is possible to prevent a decrease in the luminance maintenance rate of the lamp 5.

  Moreover, as shown in FIG. 5, you may provide the stopper 15 between the holding | maintenance part 14 and the part extended diagonally upward as mentioned above. FIG. 6A shows a front view of the socket 13 before the stopper 15 is inserted. FIG. 6B shows a front view of the socket 13 after the stopper 15 is inserted. First, as shown in FIG. 6A, the connecting portion 10 is bent excessively toward the holding portion 14 rather than a predetermined position (indicated by a one-dot chain line in the drawing). The “predetermined position” is a position where the groove portion 10 a of the connection portion 10 can contact the lead wire 6 when the glass bulb 7 of the lamp 5 is inserted into the holding portion 14. Thereafter, the stopper 15 is inserted between the connecting portion 10 and the holding portion 14, whereby the connecting portion 10 is bent back from the position indicated by the two-dot chain line in FIG. 6B to the predetermined position. As shown in FIGS. 5 and 6, the stopper 15 may be fixed by providing the holding portion 14 with a slit 14c for inserting the stopper 15 and fitting the stopper 15 into the slit 14c. You may fix by welding to 14 directly. When the plate-like connecting portion 10 is bent and processed obliquely upward, the degree of bending varies in the process, and there is a risk that the contact between the lead wire 6 and the connecting portion 10 becomes insufficient. On the other hand, by providing the stopper 15, the bending angle is forcibly made constant, and the contact between the lead wire 6 and the connecting portion 10 can be sufficiently ensured.

  Further, in the socket 8 (including modifications) according to the first embodiment of the present invention and each of the following embodiments, the groove portion 10a of the connection portion 10 may be formed of a low melting point material such as conductive rubber. In this case, when the lamp 5 is turned on and an overcurrent flows to the lamp 5 and the lamp 5 becomes abnormally hot, the low melting point material of the groove 10a is eluted and the connection portion 10 and the lead wire 6 are connected. It can be turned off by turning off. If overcurrent continues to flow through the lamp 5, there is a concern that the electrode will melt, etc., so this can be prevented beforehand.

  Further, as the material of the connection portion 10, a bimetal formed on the opposite side to the lamp 5 with a metal having a smaller thermal expansion coefficient than the lamp 5 side may be used. In this case, when an overcurrent flows to the lamp 5 and the temperature of the connecting portion 10 reaches a certain temperature or more, the connecting portion 5 is a metal side having a small thermal expansion coefficient, that is, a side away from the lead wire 6 of the lamp 5. Bending and disconnecting the lead wire 6 can stop energization.

  Note that the socket is connected to a lighting circuit (not shown) via a power supply lead wire in order to supply power to the lamp 5 in a state where it is attached to the backlight unit.

(Second Embodiment)
FIG. 7 is a perspective view of the socket 16 according to the second embodiment of the present invention. A front view of the state in which the lamp 5 is attached to the socket 16 is shown in FIG. 8, and a left side view thereof is shown in FIG. The socket 16 according to the second embodiment has substantially the same configuration as that of the socket 8 except for the connection portion 17, and therefore only the different parts will be described in detail. Description is omitted.

  The plate-like connecting part 17 extends straight from the other end of the holding part 9 in an obliquely upward direction, and in the middle thereof, a twisted part 17a twisted 90 [°] clockwise with the extending direction as the rotation axis is formed. Has been. Of course, the twisting direction may be counterclockwise. The tip of the connecting portion 17 ahead of the twisted portion 17 a remains flat and forms a contact portion 17 b that contacts the lead wire 6. In addition, the contact surface which contacts the lead wire 6 of the contact portion 17b is inclined by an angle Q with respect to the vertical direction x on the paper surface of FIG.

  The socket 16 according to the second embodiment of the present invention automates the work of assembling the lamp 5 into the backlight unit by the above configuration, similarly to the configuration of the socket 8 according to the first embodiment of the present invention. It is also possible to prevent cracks in the sealed portion of the lead wire 6 of the lamp 5 during the operation. Further, since the lamp 5 is substantially held by sandwiching the glass bulb 7 between the sandwiching pieces 9 a, no load is applied to the sealed portion of the lead wire 6 of the lamp 5 after being assembled into the socket 16. I'm sorry. Further, by appropriately changing the angle Q, after the lamp 5 is incorporated in the backlight unit, the backlight unit is swayed vertically (swaying in the vertical direction on the paper surface in FIG. 9) or swaying (on the paper surface in FIG. 9). The degree of freedom of movement of the lead wire 6 due to the shaking (lateral shaking) increases, and the force applied to the lead wire 6 can be adjusted. For example, if it is desired to suppress the force applied to the lead wire 6 when the backlight unit 21 shown in FIG. In particular, when the angle Q is 45 [°], the force applied to the lead wire 6 becomes substantially equal even when the backlight unit 21 sways and rolls, and the lead wire 6 sealing portion of the lamp 5 becomes uniform. The effect of preventing cracks from occurring can be further enhanced.

  The socket 16 may also be formed by processing a single plate material to form the holding portion 9 and the connecting portion 17, or may be separately integrated.

(Third embodiment)
FIG. 10 shows a perspective view of the socket 18 according to the third embodiment of the present invention. FIG. 11A shows a front view of the socket 18 before the lamp 5 is inserted, and FIG. 12A shows a left side view thereof. FIG. 11B shows a front view of the socket 18 in which the lamp 5 is inserted, and FIG. 12B shows a left side view thereof. FIG. 11C shows a front view of the socket 18 after the lamp 5 is inserted, and FIG. 12C shows a left side view thereof.

  Since the socket 18 according to the third embodiment also has substantially the same configuration as the first embodiment of the present invention except for the configuration of the connection portion 20, only the differences will be described in detail. The description of other configurations is omitted.

  The connecting portion 20 includes a pair of elongated plate-like connecting and holding pieces 20 a that sandwich and electrically connect the lead wire 6, one end portion connected to the connecting and holding piece 20 a, and the other end portion of the holding portion 19. A connecting piece 20b that is connected to one end portion, connects the holding portion 19 and the connecting portion 20, and is formed by bending a plate-like member into an L shape to support the connecting portion 20 with respect to the holding portion 19; Yes.

  As shown in FIGS. 11A and 12A, the pair of connecting and holding pieces 20a overlap each other as shown in FIGS. 11A and 12A when the glass bulb 7 is not sandwiched between the holding portions 19. However, in this state, the pair of connecting and holding pieces 20a are not necessarily in contact with each other, and the lead wire 6 is restored by a restoring force when the glass bulb 7 is sandwiched between the holding portions 19 as will be described later. As long as the lead wires 6 can be sufficiently clamped, the opposing surfaces may be spaced apart from each other. Further, the other end portions of the pair of connection sandwiching pieces 20a are bent in a direction away from each other (outward direction) so that the lead wire 6 can be easily inserted.

  The length M in the longitudinal direction of the lamp 5 in the connection clamping piece 20a is, for example, 2 [mm].

  The connecting piece 20b does not need to be bent in an L shape. The connecting piece 20b is such that the holding portion 19 sufficiently holds the glass bulb 7 and the connecting and holding piece 20a sufficiently holds the lead wire 6 in a state where the glass bulb 7 is sandwiched between the holding portions 19. It also has a function of adjusting the distance between the pair of members of the holding portion 19 and the connection holding piece 20a to be appropriate. Therefore, an appropriate bent shape can be selected as long as the function can be ensured.

  Next, the process of incorporating the lamp 5 when using the socket 18 will be described.

  (1) As shown in FIGS. 11 (a) and 12 (a), the socket 18 before the lamp 5 is inserted is in a state where the opposing surfaces of the pair of connection sandwiching pieces 20a of the connection portion 20 are in contact with each other. .

  (2) Next, as shown in FIGS. 11 (b) and 12 (b), the lamp 5 is assembled in the socket 18. Specifically, the glass bulb 7 is inserted into the holding portion 19. At that time, the holding portion 19 is pushed outward by the glass bulb 7 because the interval between the insertion portions 19 b at one end thereof is smaller than the outer diameter of the glass bulb 7. By this action, the connecting portion 20 connected to the holding portion 19, that is, the pair of connecting and holding pieces 20 a is also simultaneously pushed outward. At this time, the pair of connection clamping pieces 20a are separated from the contacted state so that at least the lead wire 6 can be inserted with a margin. The “margin” here is, for example, such a level that the pair of connection holding pieces 20a is not pushed and spread by the lead wire 6 when the lead wire 6 is inserted between the pair of connection holding pieces 20a. Therefore, the lead wire 6 can be inserted between the pair of connecting and holding pieces 20 a at the same time when the glass bulb 7 is inserted into the holding portion 19.

  (3) Next, as shown in FIGS. 11 (c) and 12 (c), when the glass bulb 7 of the lamp 5 has been inserted into the holding portion 19, the holding portion 19 returns inward due to its spring action. The glass bulb 7 can be held as a wax. At the same time, the pair of connecting and holding pieces 20a of the connecting portion 20 connected to the holding portion 19 also holds the lead wire 6 so as to return inward.

  The socket 18 according to the third embodiment of the present invention automates the work of assembling the lamp 5 into the backlight unit by the above configuration, similarly to the configuration of the socket 8 according to the first embodiment of the present invention. It is also possible to prevent cracks in the sealed portion of the lead wire 6 of the lamp 5 during the operation. In addition, since the lamp 5 is substantially held by sandwiching the glass bulb 7 between the clamping pieces 19a, the lead wire 6 sealing portion of the lamp 5 is not loaded after being installed in the socket 18. I'm sorry.

  The socket 18 may also be formed by processing a single plate material to form the holding portion 9 and the connecting portion 20, or may be formed by joining different materials together.

(Fourth embodiment)
FIG. 13 shows an exploded perspective view of the backlight unit 21 according to the fourth embodiment of the present invention. As shown in FIG. 13, the backlight unit 21 is a direct type, and only a plurality of lamps 5 and a surface on the optical sheet 22 side from which light is extracted are opened, and a housing 23 that houses the plurality of lamps 5. And an optical sheet 22 and a socket 8 that cover the opening of the housing. The backlight unit 21 is disposed on the back surface of a liquid crystal panel (not shown), for example, and is used as a light source device in a liquid crystal display device.

The housing 23 is made of, for example, polyethylene terephthalate (PET) resin, and a reflective surface 24 is formed by depositing a metal such as silver on the inner surface thereof. In addition, as a material of the housing | casing 23, you may comprise by metal materials, such as materials other than resin, for example, aluminum, a cold rolled material (for example, SPCC). In addition to the metal vapor-deposited film, a reflective sheet whose reflectance is increased by adding calcium carbonate, titanium dioxide (TiO ₂ ) or the like to polyethylene terephthalate (PET) resin is attached to the casing 23 as the reflective surface 24 on the inner surface. You may comprise.

  In addition, a socket 8, a lamp 5 and a cover 25 are disposed inside the housing 23. As shown in FIG. 13, at positions corresponding to both ends of the lamp 5 of the housing 23, a predetermined interval is provided in the short direction (vertical direction) of the housing 23, and a pair of first sets The socket 8 according to the embodiment is disposed via an insulator 26. The socket 8 is electrically connected to the lamp 5 by inserting the glass bulb 7 of the lamp 5 into the holding portion 9 and bringing the lead wire 6 of the lamp into contact with the connecting portion 10. For example, the socket 8 is connected to a power supply lead wire (not shown) on the bottom surface thereof, and is connected to a lighting circuit (not shown), thereby lighting the lamp 5.

  FIG. 14 is a cross-sectional view including the central axis in the longitudinal direction of the lamp 5 used in the backlight unit according to the fourth embodiment. As shown in FIG. 14, the lamp 5 is a cold cathode fluorescent lamp composed of a glass bulb 7, an electrode 27, and a lead wire 6.

  The glass bulb 7 is made of, for example, borosilicate glass, and the cross section cut perpendicularly to the tube axis has an annular shape, the overall length is 750 [mm], the outer diameter is 4 [mm], and the inner diameter is 3 [Mm] and the wall thickness is 0.5 [mm].

A phosphor layer 28 is formed on the inner surface of the glass bulb 7. For example, a rare earth composed of a red phosphor (Y ₂ O ₃ : Eu ³⁺ ), a green phosphor (LaPO ₄ : Ce ³⁺ , Tb ³⁺ ) and a blue phosphor (BaMg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ ). It is made of a phosphor.

A protective film (not shown) of a metal oxide such as yttrium oxide (Y ₂ O ₃ ), alumina (Al ₂ O ₃ ), or silica (SiO ₂ ) is provided between the inner surface of the glass bulb 7 and the phosphor layer 28. May be provided.

  The electrode 27 is a bottomed cylindrical hollow electrode made of, for example, nickel (Ni). The electrode 27 is not limited to nickel, and for example, it can be considered to be made of niobium (Nb), tantalum (Ta), molybdenum (Mo), tungsten (W), or the like.

  The electrode 27 has a total length of 5.2 [mm], an outer diameter of 2.7 [mm], an inner diameter of 2.3 [mm], and a wall thickness of 0.2 [mm]. The electrode 27 is disposed so that the tube axis of the electrode 27 and the tube axis of the glass bulb 7 are substantially aligned.

  The lead wire 6 is formed by connecting, for example, an internal lead wire 6a made of tungsten (W) and an external lead wire 6b made of nickel (Ni) that easily adheres to solder or the like, and the internal lead wire 6a and the external lead wire 6b. The joining surface is substantially flush with the outer surface of the glass bulb 7. That is, the internal lead wire 6 a is located inside the outer surface of the glass bulb 7, and the external lead wire 6 b is located outside the outer surface of the glass bulb 7.

  The internal lead wire 6a has a substantially circular cross section, a total length of 3 [mm], and a wire diameter of 1.0 [mm]. The internal lead wire 6 a has an end on the side of the external lead wire 6 b sealed to the end of the glass bulb 7, and an end on the side opposite to the external lead wire 6 b side is substantially at the center of the outer surface of the bottom of the electrode 27. It is joined.

  The external lead wire 6b has a substantially circular cross section, a total length L of 10 [mm], and a linear shape of 0.8 [mm]. The external lead wire 6b has an end portion on the electrode 27 side joined to an end portion of the internal lead wire 6a on the external lead wire 6b side.

  The configuration of the lead wire 6 is not limited to the above configuration. For example, the internal lead wire 6a and the external lead wire 6b are not separated, and the same configuration using an alloy of iron and nickel may be used.

  The tube end of the lamp 5 and the socket 8 are covered with a cover 25 as shown in FIG. The cover 25 is made of, for example, polycarbonate (PC) resin, and the surface on the optical sheet 22 side has a structure that easily diffuses white, so that the light emitted from the lamp 5 is easily diffused. Further, the cover 25 is flat so that the optical sheet 22 can be placed on the upper surface thereof.

  For example, as shown in FIG. 13, the optical sheets 22 include a diffusion plate 29, a diffusion sheet 30, and a lens sheet 31. The diffusion plate 29 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 23. The diffusion sheet 30 is made of, for example, a polyester resin. The lens sheet 31 is, for example, a laminate of an acrylic resin and a polyester resin. These optical sheets 22 are arranged so as to be sequentially superimposed on the diffusion plate 29.

  With the above configuration, the backlight unit 21 according to the fourth embodiment of the present invention can achieve high reliability against cracks in the lead wire sealing portion of the lamp. Specifically, the work of assembling the lamp 5 into the backlight unit 21 can be automated, and cracks can be prevented from occurring in the lead wire 6 sealing portion of the lamp 5 during the work. Further, since the lamp 5 is substantially held by sandwiching the glass bulb 7 between the clamping pieces 19 a, no load is applied to the sealed portion of the lead wire 6 of the lamp 5 after being assembled into the socket 8. I'm sorry.

(Fifth embodiment)
An exploded perspective view of a backlight unit according to the fifth embodiment of the present invention is shown in FIG. The backlight unit 32 according to the fifth embodiment has substantially the same configuration as the backlight unit 21 according to the fourth embodiment except for the socket 33 and the lighting circuit 35. Therefore, the socket 33 and the lighting circuit 35 will be described in detail, and the other points will be omitted.

  The backlight unit 32 according to the fifth embodiment is a position corresponding to both ends of the lamp 5 of the housing 23, and is spaced apart from each other by a predetermined interval in the short direction (vertical direction) of the housing 23. One of the sockets arranged one by one is a socket 33 into which two lamps 5 as shown in FIG. 16 can be inserted (the other socket is the first embodiment of the present invention). Socket 8 according to FIG. As shown in FIG. 16, the socket 33 is obtained by connecting the bottom surfaces of the two sockets 8 to the metal substrate 34 by welding or the like. Therefore, one lead wire 6 (the lead wires 6 such as the lamps La1 and La2 and the lamps La3 and La4 in FIG. 15) of the two adjacent lamps 5 is connected.

  Electric power is supplied to each lamp 5 provided in the backlight unit 32 from the lighting circuit 35 shown in FIG.

  FIG. 17 shows an example of the lighting circuit 35 provided in the backlight unit 32, FIG. 17A shows the lighting circuit 35, and FIG. 17B shows the connection of each lamp 5 connected to the lighting circuit 35. It is a figure which shows a relationship.

For example, as shown in FIG. 17A, the lighting circuit 35 includes a DC power supply (V _DC ), switch elements Q1 and Q2 connected to the DC power supply (V _DC ), capacitors C2 and C3, a switch element Q1 and a switch. Gates for alternately turning on and off the step-up transformers T1 and T2 (or step-up transformers T7 and T8) and the switch elements Q1 and Q2 connected between the connection point of the element Q2 and the connection point of the capacitors C2 and C3 It is composed of an inverter control IC that supplies signals.

  On the secondary side of the transformer, as shown in FIG. 17B, a series resonance circuit is formed by the transformer secondary side leakage inductance, the transformer output, the inner surface of the housing 23, and the parasitic capacitance generated in the lamp 5. The lighting circuit 35 supplies a sine wave current having a phase difference of approximately 180 degrees to two adjacent lamps La1 and La2.

  With the above configuration, the backlight unit 32 according to the fifth embodiment of the present invention can achieve high reliability against cracks in the lead wire sealing portion of the lamp. Specifically, the work of assembling the lamp 5 into the backlight unit 32 can be automated, and cracks can be prevented from occurring at the lead wire 6 sealing portion of the lamp 5 during the work. In addition, since the lamp 5 is substantially held by sandwiching the glass bulb 7 between the clamping pieces 19a, a load is applied to the sealed portion of the lead wire 6 of the lamp 5 after being assembled into the sockets 8 and 33. No need.

  Further, for example, a pseudo bent tube (U-shaped tube) can be formed by the two straight tubular lamps La1 and La2. According to this configuration, it is possible to form a pseudo-bent portion (such as a U-shaped tube) that can reduce the number of inverters in half, and in addition to a lamp having a conventional bent portion, the longitudinal direction of the lamp 5 (chassis). Uneven brightness on the left and right sides of the body can be reduced. In addition, since the straight tube lamps 5 are arranged in, for example, the vertical direction, the electrodes serving as heat generation sources do not concentrate on one side, so that it is possible to prevent a temperature difference between the right and left inside the housing 23 from occurring. As a result, the luminance unevenness of the backlight unit 32 due to the influence of the mercury vapor pressure of the lamp 5 can be suppressed.

  As shown in FIG. 17B, the plurality of lamps 5 are connected to each other by a socket 33 that is in contact with one lead wire 6 of two adjacent lamps La1 and La2. 17 (c), the socket 33 is used for connecting one lead wire between two adjacent lamps 5 or the other lead wire as shown in FIG. 17 (c). Thus, a plurality of lamps 5 arranged (for example, two adjacent lamps La1 and La2, two adjacent lamps La2 and La3, two adjacent lamps La3 and La4, and two adjacent lamps La9). La10, two adjacent lamps La10, La11, two adjacent lamps La11, La12, etc., and for the sake of clarity, the two adjacent lamps La1, La2, (Only two lamps La2 and La3 and two adjacent lamps La3 and La4 will be described), one of the lead wires 6 of the two adjacent lamps La1 and La2, and the next two adjacent lamps The sockets 8 and 33 may be arranged in a staggered manner so that the other of the lead wires 6 of the lamps La2 and La3 and the next one of the lead wires 6 of the two adjacent lamps La3 and La4 are connected in this order. . According to this configuration, the number of lighting circuits can be further reduced.

(Sixth embodiment)
FIG. 18 shows an outline of a liquid crystal display device 36 according to the sixth embodiment of the present invention. As shown in FIG. 18, the liquid crystal display device 36 is, for example, a 32-inch liquid crystal television, and includes a liquid crystal screen unit 37 including a liquid crystal panel and the like, a backlight unit 21 according to the third embodiment of the present invention, and a lighting circuit 38. Prepare.

  The liquid crystal screen unit 37 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 38 lights the lamp 5 inside the backlight unit 21. The lamp 5 is operated at a lighting frequency of 40 [kHz] to 100 [kHz] and a lamp current of 3.0 [mA] to 25 [mA].

  In FIG. 18, the backlight unit 21 according to the fourth embodiment of the present invention has been described as the light source device of the liquid crystal display device 36. However, the present invention is not limited to this, and the backlight according to the fifth embodiment of the present invention. Units can also be applied.

  As described above, according to the configuration of the liquid crystal display device 36 according to the sixth embodiment of the present invention, high reliability with respect to cracks can be realized in the lead wire sealing portion of the lamp. Specifically, the work of assembling the lamp 5 into the backlight unit 21 can be automated, and cracks can be prevented from occurring in the lead wire 6 sealing portion of the lamp 5 during the work. Further, since the lamp 5 is substantially held by sandwiching the glass bulb 7 between the clamping pieces 19 a, no load is applied to the sealed portion of the lead wire 6 of the lamp 5 after being assembled into the socket 8. I'm sorry.

(Seventh embodiment)
FIG. 19 shows a front view of a socket-equipped lamp according to a seventh embodiment of the present invention. The lamp with socket according to the seventh embodiment of the present invention is a cold cathode fluorescent lamp (hereinafter simply referred to as “lamp 40”) having sockets 39 attached to both ends. The lamp 40 has substantially the same configuration as the lamp 5 described in the fourth embodiment of the present invention, except that the sockets 39 are attached to both ends thereof. Therefore, the socket 39 will be described in detail, and description of other points will be omitted.

  As shown in FIG. 19, the socket 39 has substantially the same configuration as the socket 8 according to the first embodiment of the present invention, except that the holding section 41 has a substantially C-shaped cross section. .

  FIG. 20 shows a conceptual diagram of the process of inserting the lamp into the socket 42 of the backlight unit. Here, unlike the socket 8 according to the first embodiment of the present invention, the socket 42 of the backlight unit sandwiches the socket 39 portion of the lamp with socket. The socket 42 of the backlight unit has substantially the same configuration as the socket 8 according to the first embodiment of the present invention except that there is no connection portion. Further, the backlight unit having substantially the same configuration as that of the backlight unit 21 according to the fourth embodiment of the present invention can be used except for the configuration of the socket.

  First, as shown in FIG. 20 (a), the lamp 40 is fitted into the socket 42 from above the socket 42 as shown in FIG. 20 (b) while expanding the holding piece 9a of the holding portion 9. As a result, the socket 41 of the lamp 40 is sandwiched by the socket 42 of the backlight unit, and the lamp 40 is mechanically and electrically connected to the backlight unit.

  As described above, according to the configuration of the lamp with socket 40 according to the seventh embodiment of the present invention, cracks occur in the lead wire sealing portion of the lamp with socket 40 in the operation of attaching to the socket of the backlight unit. Can be prevented.

  By the way, the holding part of the socket is not limited to that shown in FIG. 20, but as shown in FIGS. 21 (a) and 21 (b), it is cylindrical and has a claw-shaped pin 44a on its side surface. A socket 43 having a holding portion 44 can also be employed. Unlike the socket 39 described above, the socket 43 is mounted by inserting the lead wire 6 and the tip of the glass bulb 7 from a cylindrical opening on the opposite side of the holding portion 44.

  In this case, the glass bulb 7 of the lamp 45 is mainly held only by the tip of the pin 44 a of the socket 43, and the contact area between the glass bulb 7 and the socket 43 can be reduced. By reducing the contact area between the glass bulb 7 and the socket 43, the heat generated at the electrode portion during lamp lighting is excessively released from the glass bulb 7 through the socket 43, and the periphery of the electrode portion is excessively cooled. It is possible to prevent the mercury from agglomerating around the electrode portion and the mercury in the central portion in the longitudinal direction of the lamp from being reduced to shorten the life of the lamp 45.

  Further, as shown in FIG. 21A, the connecting portion 46 is preferably in contact with a portion of the lead wire 6 that is as close to the glass bulb 7 as possible, for example, a root portion with respect to the glass bulb 7. If the lead wire 6 is in contact with the portion near the tip of the lead wire 6 opposite to the glass bulb 7, it tends to come off from the tip of the lead wire 6 when the glass bulb 7 moves in a direction parallel to the tube axis. It is. When the lead wire 6 is a connecting wire, the joining trace 6c is often located in a portion of the lead wire 6 that is exposed from the glass bulb 7 to the outside. Since the shape of the joint mark 6c may vary between lamps, it is preferable that the connecting portion 46 is connected to the lead wire 6 at a position as close as possible to the joint mark 6c while removing the joint mark 6c.

  When the connecting portion 46 extends from the holding portion 44 toward the lead wire 6, the connecting portion 46 extends from the holding portion 44 to the lead wire 6 so as to extend in a direction perpendicular to the axial center direction of the lead wire 6. Instead, it is preferable that the lead wire 6 is extended from the holding portion 44 to the lead wire 6 so as to extend in a direction obliquely intersecting the axial direction. In this case, when the socket 43 is about to come off from the glass bulb 7, the lead wire 6 moves in the axial direction, sliding on the contact surface of the connecting portion 46 on the side opposite to the protruding direction. The connecting portion 46 is folded or warped toward the glass bulb 7 with the movement. If it does so, the force which pushes the lead wire 6 of the connection part 46 will increase, and the lead wire 6 will become difficult to move. Accordingly, it is possible to prevent the socket 43 from being detached from the lamp 45 even when the lamp 45 is attached to the socket 42 of the backlight unit, exchanged, or removed. By the way, since the end of the glass bulb 7 is sealed by melting a substantially cylindrical glass tube and sealing it to bead glass or the like, the shape thereof may vary. In particular, the other end portion that is sealed after the one end portion is sealed is often unstable due to the pressure difference because the pressure of the gas sealed inside is lower than the atmospheric pressure. For example, as shown in FIG. 22 (a), one end portion thereof may have a dumpling shape (indicated by region X in FIG. 22). The length of the glass bulb 7 in the region X in the tube axis direction is, for example, about 1 [mm] to 3 [mm].

  When the region X shown in FIG. 22A is held by the holding portion 44 of the socket 43 shown in FIG. 21, the glass bulb 7 becomes unstable due to its unstable shape, and the connection portion 46 and the lead of the lamp 45 are lead. The connection with the line 6 may become unstable.

  Therefore, as shown in FIG. 22 (b), it is preferable to sandwich the portion of the glass bulb 7 that avoids the region X with the holding portion 44 of the socket 47. More preferably, the connecting portion 48 of the socket 47 is preferably not formed in close contact with the glass bulb 7 of the lamp 49, but is processed to have a predetermined distance from the glass bulb 7 by processing the shape as appropriate. In the region X, not only the diameter of the straight portion of the glass bulb 7 is smaller, but also the larger portion exists. In this case, when the connecting portion 48 is in close contact with the glass bulb 7, This is because the connecting portion 48 may be deformed so as to follow the shape of the glass bulb 7 and the connecting portion 48 and the lead wire 6 may not be connected.

  Moreover, in this embodiment and other embodiment, a part of holding | maintenance part may be mesh shape. When a negative voltage is applied to the electrode at the time of starting the lamp, ions in the glass bulb 7 are accelerated by an electric field between the electrode and a neighboring conductor such as a bottom plate of a lighting device, and collide with the electrode. Secondary electrons are generated. Then, discharge starts from the secondary electrons. However, a lamp equipped with a socket (lamp with socket) has a shorter distance between the socket and the adjacent conductor than the distance between the electrode and the adjacent conductor, and the electrode and the socket have the same potential. A strong electric field is generated between the adjacent conductors, the electric field strength between the electrode and the socket is lowered, and the acceleration action of electrons inside the glass bulb 7 is weakened, so that the discharge is difficult to occur. Dark startability deteriorates. Therefore, it is conceivable to provide an emitter closer to the center in the longitudinal direction of the lamp than the socket inside the glass bulb 7, but since this portion is a light emitting portion of the lamp, the loss of light flux in the portion where the emitter is attached May occur, which may shorten the effective light emission length.

  Therefore, by forming a part of the holding portion 41 in a mesh shape, it is possible to generate a portion having a strong electric field strength in the non-light emitting portion of the lamp 40 that is a gap portion of the mesh. Therefore, by attaching the emitter to the outer side surface of the electrode which is the non-light emitting portion of the lamp 40 or the electrode facing portion of the glass bulb 7, it is possible to improve the dark start characteristic while maintaining the effective light emission length.

(Eighth embodiment)
FIG. 23 shows a front view of a socket-equipped lamp according to an eighth embodiment of the present invention. The lamp with socket according to the eighth embodiment of the present invention (hereinafter simply referred to as “lamp 50”) is the fourth embodiment of the present invention except that sockets 51 are mounted at both ends thereof. The configuration is substantially the same as that of the lamp 5 described in FIG. Therefore, the socket 51 will be described in detail, and description of other points will be omitted.

  As shown in FIG. 23, the socket 51 is continuously formed by a single coil attached so as to contact the glass bulb 7 and the lead wire 6, respectively. In particular, a part of this coil is electrically connected to the lead wire 6. In this coil, a portion attached to the glass bulb 7 functions as a holding portion 52 (hereinafter simply referred to as “holding portion 52”), and a portion that extends from the holding portion 52 and contacts the lead wire 6 serves as a connecting portion 53. It functions (hereinafter simply referred to as “connecting portion 53”). As the material of the coil, the same material as that of the socket according to the first embodiment of the present invention can be adopted. Here, the coil diameter of the holding portion 52 is wound so as to be slightly smaller than the diameter of the glass bulb 7, and the connecting portion 53 connects the glass bulb 7 from the glass bulb tube end side of the holding portion 52, for example. It extends obliquely upward so that it can avoid the contact with the lead wire. Further, the tip of the connecting portion 53 is bent in a semicircular shape so that the lead wire is supported from the extending direction, and a bent portion 53a is formed.

  As described above, according to the configuration of the socket-equipped lamp 50 according to the eighth embodiment of the present invention, cracks occur in the lead wire sealing portion of the socket-equipped lamp 50 in the operation of attaching to the socket of the backlight unit. Can be prevented.

  Further, a portion of the coil attached to the glass bulb 7 is a gap between the coils, and a portion having a strong electric field strength is generated in the non-light emitting portion of the lamp 50, so that the outer side surface of the electrode that is the non-light emitting portion of the lamp 50 By attaching an emitter to the electrode facing portion of the bulb 7, it is possible to improve the dark starting characteristics while maintaining the effective light emission length.

<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. About glass used for glass bulb (1) About dark starting characteristics The glass used for the glass bulb 7 of the lamp is not limited to borosilicate glass but may be soda glass, lead glass, lead-free glass, or the like. When soda glass, lead glass, or lead-free glass is used, the dark startability can be improved. That is, the glass as described above contains a lot of alkali metal oxides typified by sodium oxide (Na ₂ O), and the dark startability can be improved by these alkali metal oxides. For example, when the alkali metal oxide is sodium oxide, the sodium (Na) component elutes on the inner surface of the glass bulb 7 over time. This is because sodium has a low electronegativity, so that it is considered that sodium eluted at the inner end of the glass bulb 7 (where no protective film is formed) contributes to the improvement of the dark startability.

  For example, when the alkali metal oxide is sodium oxide, the content is preferably 5 [mol%] or more and 20 [mol%] or less. If it is less than 5 [mol%], it is difficult to improve the dark start-up time, and if it exceeds 20 [mol%], the glass bulb will become black (brown) or white due to prolonged use, leading to a decrease in brightness, This is because problems such as a decrease in the strength of the glass bulb occur.

  In consideration of protection of the natural environment, it is preferable to use lead-free glass. However, even if lead-free glass is used, lead may be included as an impurity in the manufacturing process, so glass containing lead at a level of 0.1 [wt%] or less is also defined as lead-free glass. I will do it.

(2) Absorption of ultraviolet rays Absorbing ultraviolet rays of 254 [nm] or 313 [nm] by doping a glass, which is a material of the glass tube for lamp 100, 300, with a transition metal oxide by a predetermined amount. Can do. Specifically, for example, in the case of titanium oxide (TiO ₂ ), the composition ratio is 0.0.
By doping 5 [mol%] or more, 254 [nm] ultraviolet rays can be absorbed, and by doping a composition ratio of 2 [mol%] or more, 313 [nm] ultraviolet rays can be absorbed. 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 of 254 [nm] can be absorbed by doping at 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 is adjusted to be in the range of 0.3 to 1.2, particularly 0.4 to 0.8. Is preferred. When the infrared transmittance coefficient is 1.2 or less, it becomes easy to obtain a low dielectric loss tangent applicable to a high voltage application lamp such as an external electrode fluorescent lamp (EEFL) or a long cold cathode fluorescent lamp, and 0.8 or less. If so, the dielectric loss tangent becomes sufficiently small and can be applied to a high voltage application lamp.

  The infrared transmittance coefficient (X) can be expressed by the following formula.

X = (log (a / b)) / t
a: Transmittance [%] of a minimum point in the vicinity of 3840 [cm ⁻¹ ]
b: Transmittance [%] of a minimum point in the vicinity of 3560 [cm ⁻¹ ].
t: Thickness of glass (4) Shape of glass bulb The shape of the glass bulb 7 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. Good. Further, the cross section cut perpendicularly to the tube axis is not limited to a substantially circular shape, and may be, for example, a flat shape such as a track shape or a rounded corner shape, or an elliptical shape.

2. 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 rays having a wavelength of 313 [nm] may be used. The following phosphors absorb 313 [nm] ultraviolet rays.

(A) barium strontium magnesium active aluminate with blue, europium manganese co _{[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).

(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) and 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)
Note that phosphors of different compounds may be mixed and used for one kind of emission 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 105 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 that excitation light is emitted 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 is performed as part of the improvement in image quality. There is a need to expand the reproducible chromaticity range in cathode fluorescent lamps and external electrode fluorescent 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 the NTSC triangle (NTSC triangle) connecting the chromaticity coordinate values of the three primary colors of the NTSC standard in the CIE1931 chromaticity diagram. A triangular area ratio formed by connecting chromaticity coordinate values (hereinafter referred to as NTSC ratio) is used.

  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.

3. Regarding the types of lamps In the lamps with sockets according to the above embodiments, the cold cathode fluorescent lamp has been described as having a phosphor layer on the inner surface of the glass bulb. A hot cathode fluorescent lamp may be used. Moreover, the ultraviolet lamp which does not provide the fluorescent substance layer, and the mercury-free mercury lamp which does not contain mercury as a discharge medium may be used.

  The present invention can be widely applied to a socket, a lamp with a socket using the socket, a backlight unit, and a liquid crystal display device.

The perspective view of the socket which concerns on the 1st Embodiment of this invention Similarly, an enlarged front view of the main part with the lamp installed in the socket Similarly, in the socket, the enlarged left side view of the main part with the lamp installed A perspective view of a variation of the socket A perspective view of another variation of the socket (A) Front view of the state before inserting the stopper into the socket in another variation of the socket, (b) Front view of the state after inserting the stopper into the socket in another variation of the socket The perspective view of the socket which concerns on the 2nd Embodiment of this invention. Similarly, an enlarged front view of the main part with the lamp installed in the socket Similarly, in the socket, the enlarged left side view of the main part with the lamp installed The perspective view of the socket which concerns on the 3rd Embodiment of this invention. (A) Front view of the socket before the lamp is assembled, (b) Front view of the socket when the lamp is being assembled, (c) Front view of the socket after the lamp is assembled (A) Left side view of the socket before the lamp is assembled, (b) Left side view of the socket in the state of the lamp being assembled, (c) Similarly, after the lamp is assembled in the socket Left side view The disassembled perspective view of the backlight unit which concerns on the 4th Embodiment of this invention. Sectional drawing including the central axis in the longitudinal direction of the lamp also used in the backlight unit The disassembled perspective view of the backlight unit which concerns on the 5th Embodiment of this invention. A perspective view of a socket that is also used as part of the backlight unit (A) Similarly, a lighting circuit diagram of the backlight unit, (b) A diagram showing a connection relationship of each lamp connected to the lighting circuit, (c) A diagram showing a relationship of each lamp connected to the lighting circuit of the modification. Schematic of the liquid crystal display device which concerns on the 6th Embodiment of this invention. Front view of lamp with socket according to a seventh embodiment of the present invention Similarly, conceptual diagram of the process of inserting the lamp with socket into the socket of the backlight unit (A) Front view of variation 1 of lamp with socket, (b) Right side view of variation 1 of lamp with socket (A) Front view before mounting the socket of the modified example 2 of the lamp with socket, (b) Front view after mounting the socket of the modified example 2 of the lamp with socket. Front view of lamp with socket according to eighth embodiment of the present invention A perspective view of a conventional socket A perspective view of a conventional connector device

Explanation of symbols

5 Lamp 6 Lead wire 7 Glass bulb 8, 11, 13, 16, 33, 39, 43, 47, 51 Socket 9, 14, 19 Holding part 10, 12, 17 Connection part 19a Holding clamping piece 20a Connecting clamping piece 21, 32 Backlight unit 40, 45, 49, 50 Lamp with socket

Claims (6)

A socket to which a lamp having a glass bulb and a lead wire protruding from the end of the glass bulb is attached, a holding portion for holding the glass bulb, and a state in which the glass bulb is held by the holding portion And a connecting portion in contact with the lead wire. The holding part has a pair of holding and holding pieces for holding the glass bulb, and the holding and holding piece is opened so as to be once spread when the glass bulb is inserted. The glass bulb is held closed after being inserted, and the connecting portion has a connecting pinching piece to which the lead wire is pinched and connected, and opens and closes in synchronization with opening and closing of the holding pinching piece. Item 10. The socket according to item 1. A lamp with a socket having a glass bulb and a lead wire protruding from an end portion of the glass bulb, wherein the socket according to claim 1 or 2 is attached to both ends, wherein the glass bulb is the holding portion. And the lead wire is in contact with the contact portion. A backlight unit comprising the lamp and the socket according to claim 1, wherein the lamp is mounted and connected to a lighting circuit. A backlight unit comprising the lamp with socket according to claim 3. A liquid crystal display device comprising the backlight unit according to claim 4.

Images