JP2011065757A - Light shielding structure for fluorescent lamp in backlight - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light shielding structure for a folding part of a folding fluorescent lamp. <P>SOLUTION: In a lamp house 101, the folding fluorescent lamp 103 is accommodated. A lamp support 200 includes a gripping part 203a and a plate-formed light shielding part 201. The gripping part fixates a folding part 103a of the fluorescent lamp by fitting it therein. The light shielding part 201 is disposed between linear parts 103b and 103c of the fluorescent lamp and inclined toward a side surface 101b of the lamp house. The light shielding part 201 shuts light radiated to an array cell substrate by the folding part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a light shielding structure for shielding light from a part of a fluorescent lamp in a backlight used in a flat panel display, and more specifically, a light shielding structure for shielding light from a folded portion of a folded fluorescent lamp. About.

  A liquid crystal display device, which is a typical non-light emitting flat panel display, uses a backlight as a light source for displaying a screen. The backlight can be classified into a side edge type and a direct type according to the position of the light source with respect to the array cell substrate. The direct type backlight is composed of a lamp house with a reflecting plate inside, a plurality of fluorescent lamps housed therein, a diffusion plate, an optical sheet, etc. What is the display surface of the array cell substrate? A part of the liquid crystal display device is attached to the reverse back surface. The fluorescent lamp needs to be stably held in the lamp house even when the liquid crystal display device is moved or when vibration occurs in the installed state.

  There are two types of fluorescent lamps, a linear type in which electrodes are formed at both ends of a rod-like light emitting part, and a U-shaped or folded type that is folded at the center of the light emitting part so as to form a U-shape. The folded type has the advantage that the number of electrodes relative to the number of light emitting portions is halved compared to the linear type, and thus has the advantage of reducing the number of power supply parts and facilitating assembly, and is therefore used in many backlights. The backlight needs to irradiate the array cell substrate with light as uniform as possible, but the tube axis direction of the folded portion is different from the tube axis direction of the straight line portion that is the main light source, so the light distribution characteristics are It changes and appears as uneven brightness on the array cell substrate. Brightness unevenness also appears near the electrodes of the fluorescent lamp.

  In order to improve the luminance unevenness generated at the end portion of the array cell substrate, a light shielding plate called a side frame is conventionally provided in the lamp house. FIG. 4 shows a light shielding structure of a backlight using a conventional side frame. 4A is a plan view with the diffuser plate and the optical sheet removed, and FIG. 4B is a plan view with the side frames 15 and 17 removed from FIG. 4A, and FIG. These are sectional drawings which show the side surface of the folding | turning part vicinity of the fluorescent lamp seen from the AA arrow of FIG. 4 (A). 4A and 4B, three folded fluorescent lamps 13 are accommodated in the lamp house 11. The fluorescent lamp 13 has a linear portion 13a, which is a portion that effectively uses emitted light, fitted and fixed to the lamp support 19 at the center, and a folded portion 13b, which is a portion that blocks the emitted light, is attached to the lamp support 23. It is fitted and fixed.

  The electrodes provided at the ends of the straight portions 13a and 13b are connected to connectors 21 and 23, respectively. The side frames 15 and 17 are configured so that the folded portions 13b and the connectors 21 and 23 cannot be seen from the array cell substrate side at portions other than the cutout portions 15a, 15b, 17a, and 17b through which the straight portions 13a and 13b pass. It has become. Therefore, the light emitted from the folded portion 13b does not reach the array cell substrate. Patent Document 1 discloses a lighting device for a display device that illuminates a liquid crystal panel with a uniform luminance distribution by covering a folded portion of a folded fluorescent lamp with a lamp frame and shielding it. Patent Document 2 discloses a light shielding method for making the luminance distribution uniform at the bent portion of the folded fluorescent lamp. The method of this document discloses a structure in which a bent portion holding member is provided on a side plate on the bent portion side of a fluorescent lamp, and the bent portion is held from above by the bent portion holding member and light from the bent portion is shielded.

International Publication No. 2005-66704 JP 2006-164839 A

  In recent years, removal of side frames has been studied to reduce the cost of the backlight. The side frame has a light shielding function at the end of the fluorescent lamp, a pedestal function for the array cell substrate, the diffusing plate and the optical sheet, and a function for pressing and fixing the connector. If it can be easily realized without depending on the frame, the side frame on the side of the folded portion can be omitted.

  Accordingly, an object of the present invention is to provide a light shielding structure for a folded portion of a folded fluorescent lamp in a backlight. A further object of the present invention is to provide a light shielding structure with a reduced number of parts. A further object of the present invention is to provide a light shielding structure having a simple structure. Furthermore, the objective of this invention is providing the backlight and liquid crystal display device which employ | adopted such a light-shielding structure.

  The present invention provides a light-blocking structure for a folded-type fluorescent lamp in a backlight used for a flat panel display. The fluorescent lamp includes a first straight portion and a second straight portion that communicate with the folded portion. The lamp support is disposed between a grip portion that fits a fluorescent lamp and is fixed to the bottom surface of the lamp house, and a first straight portion and a second straight portion, and shields light from the folded portion. Part. Therefore, the number of parts can be reduced because the lamp support also serves as a light shielding structure. Further, the structure can be made simpler than the conventional lamp support.

  The gripping part may be fitted with the folded part of the fluorescent lamp, or may be fitted with a straight part near the folded part. The light shielding portion can be formed so that the plate-shaped member is inclined in the side surface direction of the lamp house. Further, the light shielding portion may be formed such that the plate-like member has a vertical portion perpendicular to the bottom surface of the lamp house and an inclined portion that is connected to the vertical portion and is inclined in the side surface direction. Further, the light shielding portion may be formed to have a vertical portion perpendicular to the bottom surface of the lamp house and a horizontal portion that communicates with the vertical portion and extends horizontally in the side surface direction.

  According to the present invention, it is possible to provide a light shielding structure for a folded portion of a folded fluorescent lamp in a backlight. Furthermore, according to the present invention, a light shielding structure with a reduced number of parts could be provided. Furthermore, according to the present invention, a light shielding structure having a simple structure could be provided. Further, according to the present invention, a backlight and a liquid crystal display device employing such a light shielding structure could be provided.

1 is a schematic side view of a direct backlight type liquid crystal display device according to an embodiment of the present invention. It is a figure which shows the light-shielding structure of the fluorescent lamp concerning this Embodiment. It is a figure which shows the other example of the light-shielding structure concerning this Embodiment. A conventional backlight shading structure using a side frame is shown.

  Throughout this specification, the same reference numerals are assigned to the same elements, and descriptions thereof are omitted. FIG. 1 is a schematic side view of a direct-type backlight type liquid crystal display device according to the present embodiment. The liquid crystal display device 61 includes an array cell substrate 51 and a backlight 59. In the array cell substrate 51, a liquid crystal material is enclosed in a cell gap formed between an array substrate and a color filter (CF) substrate that are arranged in parallel to face each other. The array cell substrate 51 corresponds to the active matrix system, and includes a scanning line driving IC chip and a data line driving IC chip (both not shown). The backlight 59 houses a fluorescent lamp in a lamp house 101 having a reflection sheet on the inner surface, and a diffusion plate 55 and an optical sheet 53 are provided on the light emission surface.

  FIG. 2 is a diagram showing a light shielding structure of the fluorescent lamp according to the present embodiment. 2A is a plan view of the backlight 59 in a state where the flat display panel 51, the optical sheet 53, and the diffusion plate 55 are removed, and FIG. 2B is a cross-sectional view taken along line AA in FIG. FIG. 6 is a partial side cross-sectional view including the array cell substrate 51, the optical sheet 53, and the diffusion plate 55 as viewed from the direction of the arrows. The lamp house 101 includes a bottom surface 101a, a side surface 101b, and a bent portion 101c, and can be formed by pressing a metal plate. The array cell substrate 51 is fixed to the bent portion 101c, and the optical sheet 53 and the diffusion plate 55 are fixed to the side surface 101b by a support member (not shown).

  The lamp house 101 accommodates three folded fluorescent lamps 103. In the fluorescent lamp 103, linear portions 103b and 103c communicate with both sides of the folded portion 103a. Electrodes are formed at the ends of the straight portions 103b and 103c, and the electrodes are connected to the connectors 121 and 123, respectively. The terminals of the connectors 121 and 123 are connected to an inverter circuit board provided on the back surface of the lamp house 101. The folded portion 103 a is fixed to the bottom surface 101 a of the lamp house 101 by the lamp support 200. The fluorescent lamp 103 is further fixed to the bottom surface 101a by fitting the central portions of the straight portions 103b and 103c into the holding portions of the lamp supports 119 and 120. The fluorescent lamp 103 is held in parallel with the bottom surface 101a at a predetermined distance from the bottom surface 101a of the lamp house by connectors 121, 123 and lamp supports 119, 120, 200.

  The lamp support 200 includes a pedestal part 205, a grip part 203 a, a protrusion part 207, and a light shielding part 201. The lamp support 200 can be integrally formed by injection molding or extrusion molding using plastic as a raw material. The lamp support 200 can be fixed by inserting a protrusion 207 communicating with the pedestal 205 into an opening formed in the bottom surface 101a. A gripping portion 203 a extends from the pedestal portion 205 in the direction of the array cell substrate 51. The folded portion 103a is fitted and fixed to the grip portion 203a.

  In the vicinity of the folded portion 103a, the light shielding portion 201 disposed between the straight portions 103a and 103b extends from the pedestal portion 205 in an inclined manner toward the side surface 101b of the lamp house 101. The light shielding portion 201 is formed in a plate shape, and shields light emitted from the folded portion 103a toward the array cell substrate 51. Therefore, the array cell substrate 51 is not affected by the light from the folded portion 103a having a different orientation distribution from the linear portions 103b and 103c, so that the display quality at the end can be maintained. The three fluorescent lamps 103 have the same structure, and the folded portion 103a is fixed and shielded by the lamp support 200.

  FIG. 3 is a diagram showing another structure of the lamp support. 3A is a plan view, and FIGS. 3B and 3C are cross-sectional views. The lamp support 300 in FIG. 3A includes a pedestal portion 305 and a light shielding portion 301 as in the lamp support 200, except that two gripping portions 303a and 304a are provided. The gripping portion 303a and the gripping portion 304a can be fitted and fixed to the straight portions 103b and 103c in the immediate vicinity of the folded-back portion 103a.

  In the lamp support 400 shown in FIG. 3B, a plate-shaped light shielding portion 401 disposed between the straight portions 103a and 103b extends perpendicularly from the pedestal portion 405 to the bottom surface 101a, and further toward the side surface 101b. It extends at an angle. In the lamp support 500, a plate-shaped light-shielding portion 501 disposed between the straight portions 103a and 103b extends perpendicularly from the pedestal portion 505 to the bottom surface 101a and further extends parallel to the bottom surface 101a toward the side surface 101b. ing. Although the gripping portion is omitted from the lamp supports 400 and 500, the gripping portion having the structure shown in FIG. 2 or FIG. 3 (A) can be adopted. In the present embodiment, the conventional side frame is removed by using the lamp supports 200, 300, 400, and 500 that also serve to shield the folded portion 103a of the fluorescent lamp 103 and to fix to the bottom surface 101a of the lamp house 101. can do.

  Although the present invention has been described with the specific embodiments shown in the drawings, the present invention is not limited to the embodiments shown in the drawings, and is known so far as long as the effects of the present invention are achieved. It goes without saying that any configuration can be adopted.

51 ... Array cell substrate 59 ... Backlight 61 ... Liquid crystal display device 101 ... Lamp house 103 ... Folded fluorescent lamp 103a ... Folded portion 103b, 103c ... Linear portion lamp support ... 109, 200, 300, 400, 500
Light-shielding part ... 201, 301, 401, 501
Grip part ... 203a, 303a

Claims (8)

A light blocking structure of a fluorescent lamp in a backlight used for a flat panel display,
A lamp house with a bottom and sides;
A folded fluorescent lamp that is housed in the lamp house and includes a folded portion, a first straight portion that communicates with the folded portion, and a second straight portion;
Light that is fixed between the bottom surface and is disposed between the first straight portion and the second straight portion, and the light emitted from the folded portion is fixed to the flat portion. A light shielding structure having a lamp support having a light shielding portion for removing an influence on a panel display.   The light-shielding structure according to claim 1, wherein the grip portion is fixed by fitting the folded portion.   The light-shielding structure according to claim 1, wherein the grip portion is fitted and fixed to the straight portion near the folded portion.   The light shielding structure according to any one of claims 1 to 3, wherein the light shielding portion is formed such that a plate-like member is inclined in the side surface direction.   The said light-shielding part is formed so that a plate-shaped member may have a vertical part perpendicular | vertical with respect to the said bottom face, and the inclination part which connects this vertical part and inclines in the said side surface direction. The light shielding structure according to any one of the above.   The said light-shielding part is formed so that it may have a perpendicular | vertical part perpendicular | vertical with respect to the said bottom face, and a horizontal part connected to this perpendicular | vertical part and extended horizontally in the said side surface direction. The light shielding structure described. A diffusion plate attached to the lamp house;
The backlight which has the optical sheet laminated | stacked on the said diffusion plate, and the light-shielding structure in any one of Claims 1-6. A liquid crystal display device comprising an array cell substrate and the backlight according to claim 7.

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