WO2014129369A1 - Lighting device, display device, and television receiver - Google Patents

Abstract

A backlight device (24) is provided with an LED (28), a light guide plate (20), a casing (34), and an optical sheet (18). The light guide plate (20) includes a light-emitting surface (20b) on a front surface, an opposing surface (20c) on a rear surface, and a light absorption surface (20a) on a side surface, the light guide plate (20) guiding light from the LED (28), and the light absorption surface (20a) being disposed opposite the LED (28). The casing includes at least a plate surface, and houses the LED (28) and the light guide plate (20). The plate surface is disposed opposite the opposing surface (20c). The optical sheet (18) is disposed opposite the light-emitting surface (20b), the optical sheet (18) supplying an optical function to light emitted from the light guide plate (20), and describing a square shape. The optical sheet (18) includes multiple bent sections (19) provided at two adjacent sides, the bent sections extending further outward than the edge of the light-emitting surface (20b) and bending toward the opposing surface (20c) so as to lock into the side surface of the light guide plate (20).

Description

Lighting device, display device, and television receiver

The present invention relates to a lighting device, a display device, and a television receiver.

In recent years, display elements of image display devices such as television receivers are shifting from conventional cathode ray tubes to thin display devices to which thin display elements such as liquid crystal panels and plasma display panels are applied. Is possible. The liquid crystal display device requires a backlight device as a separate illumination device because the liquid crystal panel used for this does not emit light. As an example of such a backlight device, there is known an edge light type backlight device in which a light incident surface is provided on a side surface of a light guide plate, and a light source such as an LED is arranged to face the light incident surface. Yes.

In the edge light type backlight device, an optical sheet for imparting an optical function to light emitted from the light guide plate may be disposed on the light exit surface side of the light guide plate. Such an optical sheet is positioned with respect to the light guide plate by being attached to the light guide plate using an adhesive tape or the like. However, when an adhesive tape or the like is used, the member cost increases and a process for attaching the adhesive tape in the manufacturing process is required.

Therefore, Patent Document 1 discloses a liquid crystal display device capable of positioning an optical sheet with respect to a light guide plate without using an adhesive tape or the like. In this liquid crystal display device, a protrusion that is bent on at least one side of the optical sheet is provided, and a recess is provided on a side surface of the light guide plate. And the structure by which an optical sheet is positioned with respect to a light-guide plate is implement | achieved because the said protrusion is engaged with the said recessed part.

JP 2011-186179 A

(Problems to be solved by the invention)
However, in the liquid crystal display device of Patent Document 1, a step for processing the light guide plate is required in the manufacturing process in order to provide the light guide plate with the recess. Moreover, since the light guide plate is provided with the recesses in this way, there is a concern about light leakage from the recesses, and thus the light guide performance of the light guide plate may be deteriorated.

The technology disclosed in this specification has been created in view of the above problems. In this specification, it aims at providing the technique which can position an optical sheet with respect to a light-guide plate by simple structure.

(Means for solving the problem)
The technology disclosed in this specification includes a light source, a light emitting surface provided on one plate surface, an opposite surface provided on a plate surface opposite to the light emitting surface, and at least one side surface. A light incident surface provided, wherein the light incident surface is arranged in a shape facing the light source, and a light guide plate for guiding light from the light source, and in a shape facing the opposite surface. At least a plate surface disposed, a housing member that houses at least the light source and the light guide plate, and a light emitting surface that is disposed opposite to the light emitting surface, and imparts an optical function to the light emitted from the light guide plate In addition, an optical sheet having a rectangular shape, provided on at least two adjacent sides, extends outward from an edge of the light emitting surface and is bent toward the opposite surface side. Has multiple bent parts locked to the side of the light guide plate An optical sheet, a lighting device comprising a.

In the illuminating device described above, the optical sheet is moved vertically with respect to the light guide plate by engaging the bent portions provided on at least two adjacent sides of the optical sheet having a rectangular shape with the side surfaces of the light guide plate. The relative movement is restricted for any lateral movement. As a result, the optical sheet is positioned in the vertical direction and the horizontal direction with respect to the light guide plate. As described above, in the above lighting device, the optical sheet can be positioned with respect to the light guide plate with a simple configuration without using an adhesive tape or the like or processing the light guide plate.

A reflection sheet having light reflectivity and arranged in a shape facing the opposite surface, and having a rising portion that extends outward from an edge of the opposite surface and rises toward the light emission surface side The bending part may be arranged in a shape sandwiched between a side surface of the light guide plate and the rising part.
According to this configuration, the bent portion is fixed by being sandwiched between the side surface of the light guide plate and the rising portion. As a result, the bent portion can be hardly separated from the state of being locked to the side surface of the light guide plate, and the optical sheet can be effectively positioned with respect to the light guide plate.

A reflection sheet having light reflectivity and arranged in a shape facing the opposite surface, and having a rising portion that extends outward from an edge of the opposite surface and rises toward the light emission surface side And a surrounding member disposed so as to surround a side surface of the light guide plate, and the bent portion may be sandwiched between the rising portion and the surrounding member.
According to this configuration, the bent portion is fixed by being sandwiched between the rising portion and the surrounding member. As a result, the bent portion can be hardly separated from the state of being locked to the side surface of the light guide plate, and the optical sheet can be effectively positioned with respect to the light guide plate.

The light source may be disposed between the light incident surface and the rising portion.
According to this configuration, light directed from the light source toward the opposite surface side and light directed toward the opposite side to the light incident surface side are reflected by the rising portions and directed toward the light incident surface side. . Thereby, the light incident efficiency with respect to the light-incidence surface of the light radiate | emitted from the light source can be improved.

The optical sheet may have a plurality of the bent portions on the same side.
According to this configuration, since the plurality of bent portions are locked to one side surface of the light guide plate, the optical sheet can be effectively positioned with respect to the light guide plate.

The optical sheet is composed of a plurality of sheet members, and each of the plurality of sheet members may be provided with the bent portion.
According to this configuration, when the optical sheet is composed of a plurality of sheet members, each sheet member is locked to the side surface of the light guide plate by the bent portion, so that the optical sheet is effectively attached to the light guide plate. Can be positioned.

The bent portion provided in each of the plurality of sheet members may be arranged so as not to overlap in the thickness direction of the light guide plate.
According to this configuration, when the optical sheet is composed of a plurality of sheet members, a bent portion provided in one sheet member can be prevented from interfering with a bent portion provided in another sheet member.

The optical sheet is composed of a plurality of sheet members having the same size, and the bent portion may be provided only in the sheet member disposed at a position farthest from the light emitting surface.
According to this configuration, the sheet member disposed farthest from the light emitting surface is locked to the side surface of the light guide plate by the bent portion, and the edge of the other sheet member is bent inside the bent portion. It is addressed to the department. As a result, the other sheet member is positioned with respect to the light guide plate by the bent portion, and is positioned with respect to the sheet member disposed at the position farthest from the light emitting surface. For this reason, when the optical sheet is composed of a plurality of sheet members, the number of the bent portions is reduced while realizing a configuration in which each sheet member is positioned with respect to the light guide plate, thereby simplifying the manufacturing process and cost. Can be reduced.

The bent portion may be provided so as to be locked to any one of the side surfaces of the light guide plate other than the side surface that is the light incident surface.
According to this configuration, the light emitted from the light source and directed toward the light incident surface can be prevented from being blocked by the bent portion, and the light incident efficiency with respect to the light incident surface of the light emitted from the light source can be increased. it can.

The technology disclosed in this specification can also be expressed as a display device including a display panel that performs display using light from the above-described lighting device. A display device in which the display panel is a liquid crystal panel using liquid crystal is also new and useful. A television receiver provided with the above display device is also new and useful.

(The invention's effect)
According to the technique disclosed in this specification, the optical sheet can be positioned with respect to the light guide plate without being attached to the light guide plate.

1 is an exploded perspective view of a liquid crystal display device 10 according to Embodiment 1. FIG. Sectional drawing of the cross section which cut | disconnected the liquid crystal display device 10 at the YZ plane Sectional drawing of the cross section which cut | disconnected the liquid crystal display device 10 by XZ plane 3 is an enlarged sectional view in which the vicinity of the bent portion 19 is enlarged. A perspective view of the optical sheet 18 and the light guide plate 20 in the vicinity of the bent portion 19. FIG. 6 is an exploded perspective view of a liquid crystal display device 110 according to the second embodiment. Sectional drawing of the cross section which cut | disconnected the liquid crystal display device 210 which concerns on Embodiment 3 in XZ plane The expanded sectional view which expanded the vicinity of the bending part 219 in FIG. 4 is an exploded perspective view of a liquid crystal display device 310 according to Embodiment 4. FIG. A perspective view of the optical sheet 318 and the light guide plate 320 in the vicinity of the bent portion 319.

<Embodiment 1>
Embodiment 1 will be described with reference to the drawings. In the present embodiment, a liquid crystal display device (an example of a display device) 10 including the cover panel 12 is illustrated. A part of each drawing shows an X-axis, a Y-axis, and a Z-axis, and each axis direction is drawn in a common direction in each drawing. Further, with respect to the vertical direction, FIGS. 1 to 3 are used as a reference, and the upper side of the figure is the front side and the lower side of the figure is the back side.

As shown in FIG. 1, the liquid crystal display device 10 has a vertically long rectangular shape as a whole, and a liquid crystal panel (an example of a display panel) 16 whose front side plate surface is a display surface for displaying an image, and liquid crystal A cover panel 12 arranged to face the display surface with respect to the panel 16 and an external light source arranged on the opposite side of the cover panel 12 with the liquid crystal panel 16 interposed therebetween and supplying light to the liquid crystal panel 16 And a backlight device (an example of a lighting device) 24. Furthermore, the liquid crystal display device 10 includes a casing (an example of a housing member) 34 that houses the cover panel 12, the liquid crystal panel 16, and the backlight device 24. Of the components of the liquid crystal display device 10, the cover panel 12 and the casing 34 constitute the appearance of the liquid crystal display device 10. The liquid crystal display device 10 according to the present embodiment includes a portable information terminal (such as a mobile phone, a smartphone, and a tablet notebook computer), an in-vehicle information terminal (such as a stationary car navigation system and a portable car navigation system), and a portable game. It is used for various electronic devices such as a machine. For this reason, the screen size of the liquid crystal panel 16 and the cover panel 12 constituting the liquid crystal display device 10 is about several inches to several tens of inches, and is generally sized to be classified as small or medium-sized.

First, the liquid crystal panel 16 will be described. As shown in FIG. 1, the liquid crystal panel 16 has a vertically long rectangular shape as a whole, and is formed between a pair of transparent (translucent) glass substrates 16a and 16b and both the substrates 16a and 16b. And a liquid crystal layer (not shown) including liquid crystal molecules which are interposed and whose optical characteristics change with application of an electric field. Both substrates 16a and 16b are bonded together with a sealing agent (not shown) while maintaining a gap corresponding to the thickness of the liquid crystal layer. Of the two substrates 16a and 16b, the back side (back side) is the array substrate 16b, and the front side (front side) is the CF substrate 16a. The array substrate 16b is provided with a switching element (for example, TFT) connected to a source wiring and a gate wiring orthogonal to each other, a pixel electrode connected to the switching element, an alignment film, and the like. Are provided with a color filter in which colored portions such as R (red), G (green), and B (blue) are arranged in a predetermined arrangement, a counter electrode, and an alignment film. Among these, as shown in FIG. 1, the CF substrate 16a has a short side dimension substantially equal to that of the array substrate 16b, but a long side dimension smaller than that of the array substrate 16b. Then, they are bonded together with one end in the long side direction aligned. Therefore, the other end of the array substrate 16b in the long side direction is in a state where both the front and back plate surfaces are exposed to the outside, and a driver 17 for driving the liquid crystal panel 16 or a panel side flexible A mounting area for a substrate (not shown) is secured. As a result, image data and various control signals necessary for displaying an image from a drive circuit board (not shown) are supplied to the source wiring, the gate wiring, the counter electrode, and the like. A polarizing plate (not shown) is disposed outside both substrates.

The cover panel 12 is arranged so as to cover the entire area of the liquid crystal panel 16 from the front side, whereby the liquid crystal panel 16 can be protected. A liquid crystal panel 16 is attached to the center side portion of the cover panel 12 via an adhesive 15 (see FIG. 2) on the plate surface on the back side. The cover panel 12 has a vertically long rectangular shape, similar to the liquid crystal panel 16, and the size of the cover panel 12 as viewed in a plane is slightly larger than the substrates 16 a and 16 b forming the liquid crystal panel 16. Almost the same level. Therefore, the outer peripheral side portion of the cover panel 12 protrudes outward in a bowl shape from the outer peripheral end of the liquid crystal panel 16. The cover panel 12 is formed with a light shielding portion 12a that shields light around it. The light shielding portion 12a is provided by printing means such as screen printing or ink jet printing. The light-shielding portion 12a is also formed on the outer peripheral side portion that protrudes outward from the outer peripheral end of the liquid crystal panel 16, thereby forming a vertically long substantially frame shape (substantially frame shape), thereby the backlight device 24. Can be shielded by the light shielding portion 12a at a stage before entering the plate surface on the back side of the cover panel 12 around the liquid crystal panel 16.

The casing 34 is made of a synthetic resin material or a metal material, and has a substantially box shape opened toward the front side as shown in FIG. The bottom plate portion 34a that forms the bottom plate of the casing 34 and the side wall that rises from the edge of the bottom plate portion 34a to the front side are used. The cover panel 12, the liquid crystal panel 16, and the backlight device 24 are accommodated in an accommodation space held inside the casing 34. Therefore, the casing 34 covers the backlight device 24 from the back side, and covers the backlight device 24 and the cover panel 12 from the side over the entire circumference, thereby forming the appearance of the back side and the side surface side of the liquid crystal display device 10. ing. On the bottom plate portion of the casing 34, the frame 22 described later is placed along the circumferential direction. Further, in a space between the casing 34 and the back side of the backlight device 24, substrates (not shown) such as a control board for controlling driving of the liquid crystal panel 16 and an LED driving board for supplying driving power to the LEDs 28 described later. Etc. are accommodated.

Next, the backlight device 24 will be described. The backlight device 24 includes an LED (Light） Emitting Diode) 28 that is a light source, a flexible substrate 30 on which the LED 28 is mounted and having flexibility, a light guide plate 20 that guides light from the LED 28, and the light guide plate 20. The optical sheet 18 stacked on the upper side, the reflection sheet 26 stacked below the light guide plate 20, the light guide plate 20 and the optical sheet 18 are surrounded, and the liquid crystal panel 16 is on the back side (the side opposite to the cover panel 12 side). And a frame-like frame (an example of an enclosing member) 22 that is supported from above. The backlight device 24 is a so-called edge light type (side light type) in which the LEDs 28 are unevenly distributed at the outer peripheral end of the liquid crystal panel 16. Hereinafter, each component of the backlight device 24 will be described.

The light guide plate 20 is made of a synthetic resin material (for example, acrylic resin such as PMMA or polycarbonate) having a refractive index sufficiently higher than that of air and substantially transparent (excellent translucency). As shown in FIG. 1, the light guide plate 20 has a horizontally long rectangular shape when seen in a plan view, as in the liquid crystal panel 16, and has a plate shape that is thicker than an optical sheet 18 described later. In the light guide plate 20, the short side direction on the plate surface coincides with the X-axis direction, the long side direction coincides with the Y-axis direction, and the plate thickness direction orthogonal to the plate surface coincides with the Z-axis direction. As shown in FIGS. 1 to 3, the light guide plate 20 is disposed at a position directly below the liquid crystal panel 16 and the optical sheet 18 in a state surrounded by a frame 22 described later.

Of the plate surfaces of the light guide plate 20, the surface facing the front side (the surface facing the liquid crystal panel 16 and the optical sheet 18) transmits the internal light to the optical sheet 18 and the liquid crystal panel 16 as shown in FIGS. 1 to 3. It becomes the light-projection surface 20b radiate | emitted toward the side. On the other hand, the plate surface (back surface) opposite to the light emitting surface 20b is an opposite surface 20c. Of the outer peripheral end surfaces adjacent to the plate surface of the light guide plate 20, one end surface (the right side shown in FIGS. 1 and 2) of both end surfaces provided along the X-axis direction is flexible as will be described later. Each LED 28 mounted on the substrate 30 is opposed to each other, and this is a light incident surface 20a on which light emitted from each LED 28 is incident. Of the both end surfaces of the light guide plate 20 provided along the X-axis direction, the side surface opposite to the light incident surface 20a is a first end surface 20d. In addition, both end surfaces of the light guide plate 20 provided along the Y-axis direction are second end surfaces 20e. The light guide plate 20 introduces light emitted from each LED 28 from the light incident surface 20a, and rises toward the optical sheet 18 side (front side, light emission side) while propagating the light inside, thereby emitting the light. It has the function to emit from 20b.

The frame 22 is made of synthetic resin. As shown in FIG. 1, the frame 22 has a vertically long substantially frame shape whose outer shape is substantially the same as that of the cover panel 12, and the liquid crystal panel 16, the light guide plate 20, and the optical sheet are disposed inside the frame 22. 18 is accommodated. The frame 22 includes a pair of short side portions extending along the X-axis direction and a pair of long side portions extending along the Y-axis direction. The frame 22 is opposed to the outer peripheral end portion of the cover panel 12 where the light shielding portion 12a is formed and the plate surface on the back side of the liquid crystal panel 16 and can support the plate surface from the back side over the entire circumference. . As shown in FIGS. 2 and 3, the frame 22 has a substantially stepped shape with a cross-sectional shape of three stages, and a part of the lowest first step part 22 a forms the long side of the flexible substrate 30. The end portion is supported, the second lowest step portion 22b supports the outer peripheral end portion of the liquid crystal panel 16 through the panel adhesive tape 27, and the highest third step portion 22c is the outer periphery of the cover panel 12. The end is supported from the back side.

The reflection sheet 26 is a sheet-like member having light reflectivity, and is sandwiched between the opposite surface 20c of the light guide plate 20 and the bottom plate portion 34a of the casing 34, and the edge thereof is on the light emission surface 20b side ( By forming the rising portion 26a to rise to the front side), a box shape is formed. The rising portion 26 a of the reflection sheet 26 is provided along the inner periphery of the frame 22. The rising portion 26 a of the reflection sheet 26 rises from a position extending outward from the opposite surface 20 c of the light guide plate 20. In particular, on the light incident surface 20a side of the light guide plate 20, the light incident surface 20a, the LED 28, and the surroundings are arranged so as to surround the reflection sheet 26, thereby improving the light incident efficiency on the light incident surface 20a. It is possible to do. Note that a scattering portion (not shown) that scatters the light in the light guide plate 20 is provided on at least one of the light exit surface 20b and the opposite surface 20c of the light guide plate 20 or on the surface of the reflection sheet 26. Patterning is performed so as to have an in-plane distribution, whereby the light emitted from the light emitting surface 20b is controlled so as to have a uniform distribution in the surface.

The flexible substrate 30 is formed of a film-like base material made of a synthetic resin material having insulation properties and flexibility (for example, polyimide resin), and is near the end of the light guide plate 20 on the light incident surface 20a side. It is arranged. The flexible substrate 30 has a horizontally long rectangular shape when seen in a plane, and its long side direction coincides with the X-axis direction, and its short side direction coincides with the Y-axis direction. The front surface of the flexible substrate 30 is directed to the liquid crystal panel 16 side (front side), the back surface thereof is directed to the reflection sheet 26 side, and the mounting surface on which the LEDs 28 are mounted. One end of the both ends forming the long side of the flexible substrate 30 is supported by an edge located on the light incident surface 20a side of the light emitting surface 20b of the light guide plate 20, and the other end is The substrate 22 is fixed by the substrate adhesive tape 25 while being supported by the first step 22 a of the frame 22.

A plurality of LEDs 28 are mounted on the mounting surface 30a of the flexible substrate 30 along the long side direction (X-axis direction) of the flexible substrate 30 in parallel. Each LED 28 is arranged in parallel on the mounting surface of the flexible substrate 30 such that the light emitting surface thereof faces the light incident surface 20 a side of the light guide plate 20. Out of both ends forming the long side of the flexible substrate 30, an end portion on the side supported by the frame 22 is provided with an extension portion (not shown) extending outward from a part thereof. The extension portion is provided with a connection terminal at the tip thereof, and the connection terminal is electrically connected to a power circuit board (not shown) so that power is supplied to the LED 28 and the drive of the LED 28 is controlled. Is done.

The plurality of LEDs 28 are mounted in parallel on the mounting surface of the flexible substrate 30, and the LED chip (not shown) is sealed with a resin material on the substrate portion fixed to the flexible substrate 30. The The LED chip mounted on the substrate unit has one main emission wavelength, and specifically, one that emits blue light in a single color is used. On the other hand, the resin material that seals the LED chip is dispersed and blended with a phosphor that emits a predetermined color when excited by the blue light emitted from the LED chip, and generally emits white light as a whole. It is said. In addition, as the phosphor, for example, a yellow phosphor that emits yellow light, a green phosphor that emits green light, and a red phosphor that emits red light are used in appropriate combination, or any one of them is used. It can be used alone. These LEDs 28 are of a so-called side light emitting type in which one side surface is a light emitting surface when the surface mounted on the flexible substrate 30 is the front surface (or the back surface). Each LED 28 has a light emitting surface close to the light incident surface 20a of the light guide plate 20 on the mounting surface of the flexible substrate 30 as described above, along the long side direction (X-axis direction) of the flexible substrate 30. A plurality are arranged in parallel (linearly) in a row with a predetermined interval.

Next, the configuration of the optical sheet 18 that is a main part of the present embodiment will be described in detail. The optical sheet 18 has flexibility, and has a horizontally long rectangular shape when seen in a plane, like the liquid crystal panel 16 and the bottom plate portion 34a of the casing 34, as shown in FIG. The optical sheet 18 is composed of a plurality of sheet members. Specifically, the optical sheet 18 is formed by laminating a first diffusion sheet 18a, a lens sheet 18b, and a second diffusion sheet 18c in order from the light guide plate 20 side. The optical sheet 18 is disposed between the liquid crystal panel 16 and the light guide plate 20 so as to transmit the light emitted from the light guide plate 20 and to perform a predetermined optical action such as a condensing function on the transmitted light. The light is emitted toward the liquid crystal panel 16 while being applied. The optical sheet 18 is arranged in a form slightly spaced from the liquid crystal panel 16.

Two adjacent sides of the edge of the optical sheet 18, specifically, one side of both sides along the long side direction and one side of both sides along the short side direction, A bent portion 19 that extends outward from the edge of the light emitting surface 20b of the light guide plate 20 is provided. Among these, one side along the short side direction where the bent portion 19 is provided is a side located on the side opposite to the light incident surface 20 a side of the light guide plate 20. Each bent portion 19 extends from a part of the edge forming the edge of the optical sheet 18 and is bent to the opposite surface 20c side of the light guide plate 20 (the bottom plate portion 34a side of the casing 34). Yes.

The bending portion 19 is provided on each of the three sheet members 18a, 18b, and 18c constituting the optical sheet 18. Hereinafter, the bent portions 19 corresponding to each of the first diffusion sheet 18a, the lens sheet 18b, and the second diffusion sheet 18c are sequentially referred to as a first bent portion 19a, a second bent portion 19b, and a third bent portion 19c. As shown in FIG. 1, the bent portions 19a, 19b, and 19c provided on two adjacent sides of each sheet member 18a, 18b, and 18c sandwich one corner of each sheet member 18a, 18b, and 18c. They are provided at symmetrical positions in pairs.

As shown in FIG. 5, the bent portions 19 a, 19 b, 19 c of the optical sheet 18 extend to the vicinity of the bottom plate portion 34 a of the casing 34, have the same size, and the thickness direction (Z-axis) of the light guide plate 20. In the direction). Thereby, each bending part 19a, 19b, 19c is in the state (an example of latching) which is addressed and hooked to the side surface (first end surface 20d, second end surface 20e) of the light guide plate 20, respectively. Each of the bent portions 19a, 19b, and 19c is provided between the side surface (first end surface 20d, second end surface 20e) of the light guide plate 20 and the rising portion 26a of the reflection sheet 26, as shown in FIGS. It is arranged in a sandwiched form.

As described above, in the backlight device 24 according to the present embodiment, the bent portions 19a, 19b, and 19c provided on the two adjacent sides of the optical sheet 18 having the rectangular shape are provided on the side surfaces (the first sides) of the light guide plate 20. The first end face 20d and the second end face 20e) are respectively hooked. Therefore, the optical sheet 18 can move relative to the light guide plate 20 with respect to both the vertical movement (movement along the Y-axis direction) and the horizontal movement (movement along the X-axis direction). It is a regulated structure. As a result, the optical sheet 18 is positioned in the vertical direction (Y-axis direction) and the horizontal direction (X-axis direction) with respect to the light guide plate 20 by the bent portions 19a, 19b, and 19c. As described above, in the backlight device 24 according to the present embodiment, the optical sheet 18 is positioned with respect to the light guide plate 20 with a simple configuration without using an adhesive tape or the like or processing the light guide plate 20. be able to.

Further, the backlight device 24 according to the present embodiment has a rising portion 26a that extends outward from the edge of the opposite surface 20c of the light guide plate 20 and rises toward the light emitting surface 20b side (front side). 26. And each bending part 19a, 19b, 19c of the optical sheet 18 is distribute | arranged in the form clamped between the side surface (1st end surface 20d, 2nd end surface 20e) of the light-guide plate 20, and the standing part 26a. Thus, the structure by which the bending part 19 was fixed is implement | achieved by pinching the bending part 19 between the side surface of the light-guide plate 20, and the standing part 26a. As a result, it is possible to make it difficult to separate the bent portion 19 from the state of being hooked (locked) on the side surface of the light guide plate 20, and to effectively position the optical sheet 18 with respect to the light guide plate 20. Can do.

Further, in the backlight device 24 according to the present embodiment, the LED 28 is disposed between the light incident surface 20 a of the light guide plate 20 and the rising portion 26 a of the reflection sheet 26. With this configuration, the light emitted from the LED 28 toward the opposite surface 20c and the light toward the opposite side of the light incident surface 20a are reflected by the rising portion 26a. Then, it goes to the light incident surface 20a side. Thereby, the light-incidence efficiency with respect to the light-incidence surface 20a of the light radiate | emitted from LED28 can be improved.

In the backlight device 24 according to the present embodiment, the optical sheet 18 is composed of a plurality of sheet members 18a, 18b, and 18c, and a bent portion 19a is formed on each of the plurality of sheet members 18a, 18b, and 18c. , 19b, 19c are provided. With such a configuration, the sheet members 18a, 18b, and 18c are hooked on the side surfaces of the light guide plate 20 by the bent portions 19a, 19b, and 19c, so that the optical sheet 18 is attached to the light guide plate 20. It can position effectively with respect to it.

In the backlight device 24 according to the present embodiment, the bent portions 19a, 19b, and 19c provided in each of the plurality of sheet members 18a, 18b, and 18c forming the optical sheet 18 are arranged in the thickness direction of the light guide plate 20 ( (Z-axis direction) is arranged so as not to overlap in the direction. With such a configuration, the bent portion 19a (19b, 19c) provided in one sheet member 18a (18b, 18c) is bent in the other sheet member 18b (18a, 18c). (19a, 19c) may not be interfered.

In the backlight device 24 according to the present embodiment, each of the bent portions 19a, 19b, and 19c has two side surfaces (the first end surface 20d and the first end surface 20d) other than the side surfaces of the light guide plate 20 that are the light incident surfaces 20a. Two end faces 20e) are provided so as to be hooked. With such a configuration, the light emitted from the LED 28 and directed toward the light incident surface 20a can be prevented from being blocked by each of the bent portions 19a, 19b, and 19c, and emitted from the LED 28. The light incident efficiency with respect to the light incident surface 20a can be increased.

<Embodiment 2>
A second embodiment will be described with reference to the drawings. The second embodiment is different from the first embodiment in the arrangement of the bent portions 119. Since the other configuration is the same as that of the first embodiment, the description of the structure, operation, and effect is omitted. In FIG. 6, the parts obtained by adding the numeral 100 to the reference numerals in FIG. 1 are the same as the parts described in the first embodiment.

In the backlight device 124 according to the second embodiment, as shown in FIG. 6, two bent portions 119a (119b, 119c), 119a1 (119b1, 119c1) is provided. Specifically, among the sides of the sheet members 118a, 118b, and 118c of the optical sheet 118, another side of the light guide plate 120 on the side of the second end face 120e (hereinafter referred to as an auxiliary folding unit). ) 119a1 (119b1, 119c1) is provided. The auxiliary bent portion 119a1 (119b1, 119c1) is provided at a position near the light incident surface 120a on the side on the second end surface 120e side, and has the same configuration as the other bent portions 119a (119b, 119c). And size.

The backlight device 124 according to the second embodiment is configured as described above, so that two bent portions 119a (119b and 119c) are formed with respect to one side surface (second end surface 120e) of the light guide plate 120. Since 119a1 (119b1, 119c1) is locked, the optical sheet 118 can be effectively positioned with respect to the light guide plate 120.

<Embodiment 3>
Embodiment 3 will be described with reference to the drawings. The third embodiment is different from the first embodiment in the arrangement of the bent portions 219. Since the other configuration is the same as that of the first embodiment, the description of the structure, operation, and effect is omitted. 7 and FIG. 8, the part obtained by adding the numeral 200 to the reference numerals in FIG. 3 and FIG. 4 is the same as the part described in the first embodiment.

In the backlight device 224 according to the third embodiment, as illustrated in FIGS. 7 and 8, the bent portion 219 of the optical sheet 218 is configured to be sandwiched between the rising portion 226 a of the reflective sheet 226 and the frame 222. ing. In the backlight device 224 of the present embodiment, the bent portion 219 is fixed by holding the bent portion 219 between the rising portion 226a and the frame 222 in this manner. As a result, the bent portion 219 can be made difficult to separate from the state of being hooked on the side surface of the light guide plate 220, and the optical sheet 218 can be effectively positioned with respect to the light guide plate 220.

<Embodiment 4>
Embodiment 4 will be described with reference to the drawings. The fourth embodiment is different from the first embodiment in the number and size of the bent portions 319c2. Since the other configuration is the same as that of the first embodiment, the description of the structure, operation, and effect is omitted. 9 and FIG. 10, the part obtained by adding the numeral 300 to the reference numerals in FIG. 1 and FIG. 5 is the same as the part described in the first embodiment.

In the backlight device 324 according to the fourth embodiment, as illustrated in FIGS. 9 and 10, the three sheet members 318 a, 318 b, and 318 c constituting the optical sheet 318 are positioned farthest from the light emitting surface 320 b. A bent portion 319c2 is provided only on the disposed sheet member 318c, that is, the second diffusion sheet 318c. Further, as shown in FIG. 10, the bent portion 319c2 in the present embodiment is slightly larger than the bent portions 19a, 19b, and 19c in the first embodiment.

In the backlight device 324 according to the fourth embodiment, the sheet member (second diffusion sheet) 318c arranged at the position farthest from the light exit surface 320b of the light guide plate 320 is configured as described above. The bent portion 319c2 is engaged with the side surface of the light guide plate 320. Furthermore, the edges of the other sheet members (first diffusion sheet, lens sheet) 318a and 318b are directed to the bent portion inside the bent portion 319c2. As a result, the other sheet members 318a and 318b are positioned with respect to the light guide plate 320 by the bent portion 319c2, and are also positioned with respect to the sheet member 318c disposed at the position farthest from the light emitting surface 320b. It will be. Therefore, when the optical sheet 318 includes a plurality of sheet members 318a, 318b, and 318c as in the present embodiment, the configuration in which the sheet members 318a, 318b, and 318c are positioned with respect to the light guide plate 320 is realized. By reducing the number of the bent portions 319c2, the manufacturing process can be simplified and the cost can be reduced.

The modifications of the above embodiments are listed below.
(1) In each of the above embodiments, the configuration in which the bent portion is provided on two adjacent sides of the optical sheet is exemplified, but the configuration in which the bent portion is provided on three sides of the optical sheet may be used. The part provided in all the sides of the optical sheet may be sufficient.

(2) In each of the above-described embodiments, the optical sheet is exemplified by three sheet members. However, the configuration of the optical sheet is not limited.

(3) In each of the above embodiments, the configuration in which the surrounding member is a frame is illustrated, but the present invention is not limited to this. The enclosing member may be a member arranged so as to surround the side surface of the light guide plate.

(4) In each of the embodiments described above, the configuration in which one or two bent portions are provided on one side of the optical sheet is exemplified, but the number of bent portions provided on one side of the optical sheet is not limited. .

(5) In each of the above embodiments, the liquid crystal display device classified as small or medium-sized was exemplified, but the present invention is also applied to a liquid crystal display device classified into large size, for example, a liquid crystal display device used in a large television receiver. The invention is applicable.

(6) In each of the above embodiments, a so-called cabless type liquid crystal display device that does not include a cabinet has been illustrated, but the present invention can also be applied to a liquid crystal display device that includes a cabinet.

(7) In addition to the above embodiments, the number, arrangement, size, and the like of the bent portions can be changed as appropriate.

(8) In each of the above embodiments, a liquid crystal display device using a liquid crystal panel as the display panel has been exemplified. However, the present invention can be applied to a display device using another type of display panel.

(9) In each of the above embodiments, the television receiver provided with a tuner has been exemplified. However, the present invention can also be applied to a display device that does not include a tuner.

As mentioned above, although each embodiment of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

Further, the technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

10, 210, 310 ... Liquid crystal display device, 12, 212, 312 ... Cover panel, 16, 116, 216, 316 ... Liquid crystal panel, 18, 118, 218, 318 ... Optical sheet, 18a, 118a, 218a, 318a ... No. 1 diffusion sheet, 18b, 118b, 218b, 318b ... lens sheet, 18c, 118c, 218c, 318c ... second diffusion sheet, 19, 119, 219, 319c2 ... bent portion, 19a, 119a, 119a1, 219a ... first bent Part, 19b, 119b, 119b1 ... second bent part, 19c, 119c, 119c1 ... third bent part, 20, 120, 220, 320 ... light guide plate, 20a, 120a, 220a, 320a ... light incident surface, 20b, 120b , 220b, 320b ... light exit surface, 20c, 120c, 2 0c, 320c ... opposite surface, 22, 122, 222, 322 ... frame, 24, 124, 224, 324 ... backlight device, 26, 126, 226, 326 ... reflective sheet, 27, 127, 227, 327 ... for panels Adhesive tape, 28, 128, 228, 328 ... LED, 30, 130, 230, 330 ... Flexible substrate, 34, 134, 234, 334 ... Casing

Claims (12)

A light source;
A light emitting surface provided on one plate surface, an opposite surface provided on a plate surface opposite to the light emitting surface, and a light incident surface provided on at least one side surface, A light incident surface disposed in a shape facing the light source, and a light guide plate for guiding light from the light source;
A housing member that has at least a plate surface arranged to face the opposite surface, and that houses at least the light source and the light guide plate;
An optical sheet that is arranged in a shape facing the light emitting surface, imparts an optical function to the light emitted from the light guide plate, and has a rectangular shape, and is provided on at least two adjacent sides. An optical sheet that has a plurality of bent portions that extend outward from the edge of the light exit surface and are bent toward the opposite surface side to be locked to the side surface of the light guide plate;
A lighting device comprising: A reflection sheet having light reflectivity and arranged in a shape facing the opposite surface, and having a rising portion that extends outward from an edge of the opposite surface and rises toward the light emission surface side A reflective sheet having
The illuminating device according to claim 1, wherein the bent portion is arranged in a shape sandwiched between a side surface of the light guide plate and the rising portion. A reflection sheet having light reflectivity and arranged in a shape facing the opposite surface, and having a rising portion that extends outward from an edge of the opposite surface and rises toward the light emission surface side A reflective sheet having
A surrounding member disposed in a shape surrounding the side surface of the light guide plate, and
The lighting device according to claim 1, wherein the bent portion is sandwiched between the rising portion and the surrounding member. The lighting device according to claim 2 or 3, wherein the light source is disposed between the light incident surface and the rising portion. The lighting device according to any one of claims 1 to 4, wherein the optical sheet has a plurality of the bent portions on the same side. The lighting device according to any one of claims 1 to 5, wherein the optical sheet is composed of a plurality of sheet members, and each of the plurality of sheet members is provided with the bent portion. The lighting device according to claim 6, wherein the bent portion provided in each of the plurality of sheet members is disposed so as not to overlap in a thickness direction of the light guide plate. The optical sheet is composed of a plurality of sheet members having the same size, and the bent portion is provided only in the sheet member disposed at a position farthest from the light emitting surface. Item 6. The lighting device according to any one of Items 5. The said bending part is provided in the form latched by any side surfaces other than the side surface made into the said light-incidence surface among the side surfaces of the said light-guide plate. The lighting device described in 1. A display device comprising: the illumination device according to any one of claims 1 to 9; and a display panel that performs display using light from the illumination device. The display device according to claim 10, wherein the display panel is a liquid crystal panel using liquid crystal. A television receiver comprising the display device according to claim 10 or 11.

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