JP2009199850A - Case frame and backlight unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a case frame and a backlight unit, which allow uniform light to be radiated to a light-guide plate by preventing a light-emitting device from being laterally shifted with respect to the light-guide plate. <P>SOLUTION: In a case frame 7 of the backlight unit having a holding part 72 which is mounted on a substrate 21 and houses a linear light source device 2 having one or more light-emitting elements 22 sealed by a resin sealing part 23, and an underframe part 71 which receives light from the light-emitting elements 22 via the side surfaces, and houses the light-guide plate 3 for emitting the received light from the main light-emitting surface as the illumination light, the holding part 72 includes: a floor part 721 on which the substrate 21 is placed in a state that its mounting surface having the light-emitting elements 22 thereon is directed to the side surface of the light-guide plate 3; and a wall part 722 which is located on the mounting surface side of the substrate 21 and is erected on the floor part 721. An opening H fitted to the resin sealing part 23 projectingly installed on the substrate 21 is provided on the wall part 722. An abutting part 723 abutting on the backside opposite to the mounting surface of the substrate 21 is provided at the holding part 72. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light emitting device that serves as a light source, a case frame that accommodates light from the light emitting device from one side surface and a light guide plate that emits light from the main light emitting surface as illumination light, and a backlight using the case frame Regarding the unit.

  In the backlight unit, a light emitting element, which is a point light source mounted on a substrate, is placed on a case frame that surrounds the side surface of the light guide plate so as to irradiate one side of the light guide plate. By entering and exiting from the main irradiation surface of the light guide plate, it functions as a surface light emitting device that illuminates a display panel such as an LCD brightly.

Such a backlight unit is described in Patent Document 1. Patent Document 1 describes a backlight assembly including a white light emitting unit that is a light emitting device, a light guide plate, an optical sheet, and a frame-shaped mold frame that is a case frame as a backlight unit. . The white light emitting unit includes a printed circuit board, a plurality of light emitting diodes mounted on the printed circuit board, and a lens housed in a housing groove of the light guide plate, and is disposed on one side of the upper part of the mold frame. Since the reflection bands are arranged on the upper and lower surfaces of the lens, the light emitted from the lens is reflected into the lens. The substrate of the white light emitting unit is fixed to the mold frame by a stiffener containing a substance having a predetermined adhesive force.
JP 2006-108606 A

  However, in the backlight assembly described in Patent Document 1, the substrate is fixed inside the mold frame. However, in order to place the substrate inside the mold frame, the length of the substrate is set inside the mold frame. Since there is a need to have a margin that is somewhat shorter than the length, there is a risk of being displaced and fixed in the direction along the side surface of the light guide plate (hereinafter, the substrate is displaced in the direction along the side surface of the light guide plate. This is referred to as “lateral slip”.)

  If the substrate is arranged laterally offset from the mold frame, the light emitting device and the light guide plate are also laterally offset, so that the corners of the light guide plate on which the light emitting device is offset become brighter and the light guide on the remote side is guided. The corner of the light plate becomes dark, and the side surface of the light guide plate cannot be uniformly irradiated.

  Accordingly, an object of the present invention is to provide a case frame and a backlight unit capable of irradiating the light guide plate with uniform light by preventing the light emitting device from being laterally displaced with respect to the light guide plate. To do.

  The present invention includes a holding unit that houses a light emitting device provided with one or more light source units each including a light emitting element mounted on a substrate, light from the light source unit is incident from one side surface, and illumination light from a main light emitting surface. In a case frame of a backlight unit in which a frame base portion that stores an outgoing light guide plate is formed, the holding portion has a mounting surface on which the light source portion is mounted facing one side surface of the light guide plate. A light source portion provided on the wall portion, the floor portion on which the substrate is placed; and a wall portion that is located on the mounting surface side of the substrate and is erected on the floor portion. It is characterized in that an opening for fitting is provided.

  According to the present invention, the light source unit protruding from the substrate is fitted into the opening, so that the light emitting device is restricted from moving with respect to the side surface of the light guide plate. In this state, the light emitting device can be prevented from being fixed to the case frame. Therefore, it is possible to irradiate the light guide plate with uniform light.

  According to a first aspect of the present application, a light-emitting device provided with one or more light source units including a light-emitting element mounted on a substrate, and a light from the light source unit are incident from one side and are mainly used as illumination light. In the case frame of the backlight unit in which the frame base portion that stores the light guide plate that emits from the light emitting surface is formed, the holding portion is in a state where the mounting surface on which the light source portion is mounted faces one side surface of the light guide plate. A floor portion on which the substrate is placed and a wall portion that is positioned on the mounting surface side of the substrate and is erected on the floor portion, and the wall portion has an opening that fits into the light source portion protruding from the substrate Is provided.

  The case frame of the backlight unit according to the present invention has a mounting surface on one side surface of the light guide plate, since an opening that fits into the light source unit of the light emitting device is provided in the wall unit standing on the floor of the holding unit. With the substrate facing, the substrate is placed on the floor, and the light source protruding from the substrate is fitted into the opening to restrict the light emitting device from moving relative to the side surface of the light guide plate. can do. Therefore, it is possible to prevent the light emitting device from being fixed to the case frame while being laterally displaced from the light guide plate.

  The second invention of the present application is characterized in that, in the first invention, the holding portion is provided with an abutting portion that abuts against a back surface opposite to the mounting surface of the substrate.

  In the second invention of the present application, since the contact portion is provided in the holding portion when contacting the back surface of the substrate, displacement of the substrate is regulated so that the substrate of the light emitting device is sandwiched between the wall portion and the contact portion. Therefore, not only the lateral shift can be prevented but also the light emitting device can be prevented from being separated from the light guide plate.

  A third invention of the present application is characterized in that, in the first or second invention of the present application, a reflection part that reflects light from the light source part is provided on an edge surface of the opening of the wall part. It is.

  In 3rd invention of this application, the edge surface of the opening of a wall part functions as a reflection part which reflects the light from a light source part, and makes the light from a light source part enter into one side of a light-guide plate efficiently. be able to. Moreover, it is not necessary to provide the light-emitting device with reflecting portions that reflect light from the light-emitting element measurement on both sides of the light-emitting element.

  According to a fourth invention of the present application, a light emitting device provided with one or more light source parts including a light emitting element mounted on a substrate, light from the light source part is incident from one side surface, and is emitted from the main light emitting surface as illumination light. In a backlight unit having a light guide plate, a holding portion that houses a light emitting device, and a case frame on which a frame base portion that houses a light guiding plate is formed, the holding portion of the case frame is a mounting surface on which a light emitting element is mounted. With a floor portion on which the substrate is placed with the light guide plate facing one side of the light guide plate and a wall portion standing on the floor portion, and the wall portion is fitted with a resin portion protruding from the substrate It is characterized in that an opening is provided.

  The backlight unit of the present invention has a mounting surface on one side surface of the light guide plate, since an opening that fits into the light source unit of the light emitting device is provided in the wall unit standing on the floor of the holding unit of the case frame. With the substrate facing, the substrate is placed on the floor, and the light source protruding from the substrate is fitted into the opening to restrict the light emitting device from moving relative to the side surface of the light guide plate. can do. Therefore, it is possible to prevent the light emitting device from being fixed to the case frame while being laterally displaced from the light guide plate.

  According to a fifth invention of the present application, in the fourth invention, the edge surface of the opening of the wall portion is formed substantially perpendicular to the one side surface of the light guide plate, and both end surfaces of the light source portion of the light emitting device are edges. It is characterized by being formed substantially parallel to the surface.

  In the fifth invention of the present application, the edge surface of the opening of the wall portion is formed substantially perpendicular to the one side surface of the light guide plate, and both end surfaces of the light source portion of the light-emitting device are approximately the edge surface. By being formed in parallel, the edge surface and the end surface of the light source unit are fitted to each other, so that it is less likely to be laterally displaced. Therefore, the light emitting device can be accurately placed on the case frame.

  According to a sixth invention of the present application, in the fourth invention, the light source part of the light emitting device is formed with a resin sealing part that seals the light emitting element and is fitted to the opening of the wall part. It is characterized by being formed in a convex lens shape.

  In the sixth invention of the present application, since the resin sealing portion of the light emitting device is formed in a convex lens shape, light directed to the side of the light emitting element is emitted from the resin sealing portion formed in the convex lens shape. In this case, the light can be refracted and directed toward the side surface of the light guide plate, so that the light emission efficiency of the light emitting device can be increased.

  According to a seventh invention of the present application, in any one of the fourth to sixth inventions, the opening surface of the wall portion is provided with a reflection portion that reflects light from the light source portion. is there.

  In 7th invention of this application, the edge surface of the opening of a wall part functions as a reflection part which reflects the light from a light source part, and makes the light from a light source part enter into one side of a light-guide plate efficiently. be able to. Moreover, it is not necessary to provide the light-emitting device with reflecting portions that reflect light from the light-emitting element measurement on both sides of the light-emitting element.

(Embodiment 1)
The configuration of the backlight unit according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view of a backlight unit according to Embodiment 1 of the present invention. FIG. 2 is a plan view showing a linear light source device of a backlight unit as shown in FIG.

  As shown in FIG. 1, the backlight unit 1 includes a linear light source device 2, a light guide plate 3, a light control sheet 4, a light shielding sheet 5, a reflection sheet 6, and a case frame 7, and a liquid crystal display Illumination light is irradiated from the back of the device or the like.

  As shown in FIG. 2, the linear light source device 2 is a light emitting device including a substrate 21, a light emitting element 22, a resin sealing portion 23, and a printed wiring board 24.

  The substrate 21 is a printed wiring board in which a wiring pattern is formed on a long and thin insulating substrate. The insulating substrate can be formed of glass epoxy resin, BT resin (bismaleimide triazine resin thermosetting resin), or the like.

  The light emitting element 22 is formed by stacking a semiconductor layer including a light emitting layer on a conductive substrate formed of a semiconductor or an insulating substrate formed of sapphire. It is mounted on F.

  The resin sealing portion 23 is formed by sealing the light emitting element 22 with an epoxy resin, and is formed in a convex lens shape by gradually decreasing the thickness from the center toward the periphery. The resin sealing portion 23 is formed with a high positional accuracy with respect to the substrate 21 by being formed by a transfer molding method. In the linear light source device 2 according to the first embodiment, a light source unit is configured by the light emitting element 22 and the resin sealing unit 23. Four light source portions are provided on the substrate 21. The resin sealing portion 23 can contain a phosphor that emits light that is excited by light from the light emitting element 22 and wavelength-converted as necessary. For example, if the light emitting element 22 emits blue light, if the phosphor emits light of yellow that is a complementary color of blue, the light source unit may emit blue light by mixing blue and yellow. it can.

  The printed wiring board 24 includes a connection portion 241 formed along the substrate 21 and a wiring portion 242 connected to a connector that supplies power, and is formed of a flexible flexible substrate. The printed wiring board 24 is fixed to the substrate 21 by terminals connected to the electrodes provided on the substrate 21 being electrically connected by solder B.

  As shown in FIG. 1, the light guide plate 3 is one in which light from the linear light source device 2 is incident from the side surface and exits from the main light emitting surface as illumination light. For example, the light guide plate 3 is 0.3 by acrylic resin or polycarbonate resin. A transparent or translucent plate-like body formed to a thickness of about 0.6 mm.

  The light control sheet 4 includes a diffusion sheet 41, a first prism sheet 42, and a second prism sheet 43. The diffusion sheet 41 is made of polyester (PS) resin or polycarbonate (PC) resin and has a rough surface like ground glass. The first and second prism sheets 42 and 43 have prism surfaces in which triangular strips made of acrylic resin are formed on the surface of a polyester resin. This prism surface is formed in a sawtooth shape in a sectional view. The first and second prism sheets 42 and 43 are arranged so that the strip directions overlap in a direction substantially orthogonal to each other.

  The light shielding sheet 5 is formed so as to cover the entire light guide plate 3. A black frame 5 a that shields light is printed on the light shielding sheet 5 so as to surround an illumination region through which light is transmitted.

  The reflection sheet 6 has a function of reflecting light from the bottom surface of the light guide plate 3 toward the light guide plate 3. As the reflection sheet 6, an ESR (Enhanced Specular Reflector) having a high reflectance in the visible light range can be used due to a multilayer film structure using a polyester-based resin, but the light from the light guide plate 3 can be reflected by a metallic luster or the like. Any other material may be used.

  The case frame 7 is formed of, for example, white acrylic resin or polycarbonate resin, and a frame portion 71 (see FIG. 3) that houses the light guide plate 3, the light control sheet 4, the light shielding sheet 5, and the reflection sheet 6, and a line And a holding portion 72 for storing the light source device 2. In the linear light source device 2, the reflective film 8 is affixed to the upper portion of the light guide plate 3 and the resin sealing portion 23 along the linear light source device 2 while being accommodated in the case frame 7. . The printed wiring board 24 connected to the linear light source device 2 is bonded to the holding portion 72 with the adhesive sheet 9. Since the cross section of the underframe portion 71 is formed in an approximately L shape, the light guide plate 3 is positioned and accommodated inside.

  Here, the holding | maintenance part 72 of the case frame 7 is demonstrated in detail based on FIG. 3 and FIG. FIG. 3 is an enlarged view of a main part of the case frame according to Embodiment 1 of the present invention. 4 is an enlarged view of a main part showing a state in which the light guide plate and the linear light source device are arranged on the case frame shown in FIG.

  As shown in FIG. 3, the holding portion 72 includes a floor portion 721 on which the substrate 21 is placed, a wall portion 722 that is positioned on the mounting surface F side of the substrate 21 and is erected on the floor portion 721, and the substrate 21. And an abutting portion 723 that abuts against the back surface R of the lens.

  The floor portion 721 is formed so as to connect the end portions of the frame portion 71, and the substrate 21 of the linear light source device 2 is placed with the mounting surface F facing the side surface of the light guide plate 3. The wall portion 722 is erected on the mounting surface F side of the substrate 21, and an opening H having substantially the same width as the resin sealing portion 23 of the linear light source device 2 is provided. The edge surface 722 a of the opening H is formed to be substantially perpendicular to the side surface of the light guide plate 3. In the first embodiment, the edge surface 722a is formed so as to be substantially perpendicular to the side surface of the light guide plate 3. However, the wall portion 722 gradually approaches the side surface of the light guide plate 3. You may form so that the opening H may spread. By forming the opening H of the wall portion 722 so as to gradually spread toward the side surface of the light guide plate 3, the irradiation light from the light emitting element 22 is reflected on the edge surface 722a or directly irradiated, The light can be incident on the side surface of the light guide plate 3 in a wide range.

  The contact portion 723 is formed in a convex shape by a concave portion 724 for avoiding the rise of the solder B that fixes the substrate 21 of the linear light source device 2 and the printed wiring board 24. The contact portion 723 is formed such that the distance L between the contact portion 723 and the wall portion 722 becomes the thickness of the substrate 21 of the linear light source device 2.

  When the linear light source device 2 is arranged in the holding portion 72 formed in this way, the opening H of the wall portion 722 is formed to have substantially the same width as the resin sealing portion 23 protruding from the substrate 21. Since the resin sealing portion 23 is fitted into the opening of the wall portion 722, the linear light source device 2 is restricted from moving in the direction along the side surface of the light guide plate 3. Therefore, the linear light source device 2 can be prevented from being laterally displaced with respect to the light guide plate 3, so that the light guide plate 3 can be irradiated with uniform light.

  In addition, since the substrate 21 of the linear light source device 2 is sandwiched between the wall portion 722 and the contact portion 723 to prevent the substrate from shifting, the linear light source device 2 is not only prevented from being laterally displaced, but the linear light source device 2 is also prevented. Can be prevented from separating from the light guide plate 3.

  Further, the light traveling toward the side of the light emitting element 22 can be refracted when emitted from the resin sealing portion 23 formed in a convex lens shape, and can be converted into light traveling toward the side surface of the light guide plate 3. The light emission efficiency of the light source device 2 can be increased.

  Furthermore, since the case frame 7 is formed of white acrylic resin, polycarbonate resin, or the like, the light from the resin sealing portion 23 is reflected on the edge surface 722a of the wall portion 722 and directed toward the light guide plate 3. Therefore, the luminous efficiency of the linear light source device 2 can be further improved. Further, since the edge surface 722a of the opening H of the wall portion 722 fitted with the resin sealing portion 23 functions as a reflection portion, the light source formed by the light emitting element 22 and the resin sealing portion 23 of the linear light source device 2 It is not necessary to provide a new reflecting part on both sides of the part.

(Embodiment 2)
A backlight unit according to Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 5 is a plan view showing a linear light source device according to Embodiment 2 of the present invention. FIG. 6 is an enlarged view of a main part showing a state in which the linear light source device shown in FIG. 5 is arranged in the case frame together with the light guide plate. In FIG. 5, the same components as those in FIG. 2 and FIG. 6 in FIG.

  As shown in FIGS. 5 and 6, in the linear light source device 2x according to the second embodiment, the resin sealing portion 23x is formed in a substantially rectangular shape in plan view. That is, since the edge surface 722a of the opening H is formed to be substantially perpendicular to the side surface of the light guide plate 3, both end surfaces of the resin sealing portion 23x are formed substantially parallel to the edge surface 722a. ing. In the second embodiment, the edge surface 722a is formed to be substantially perpendicular to the side surface of the light guide plate 3, and both end surfaces of the resin sealing portion 23x are substantially parallel to the edge surface 722a. However, even if the angle formed between the edge surface 722a and the both end surfaces of the resin sealing portion 23x and the side surface of the light guide plate 3 is not strictly 90 °, the difference in manufacturing error is Can be tolerated.

  The edge surface 722a of the opening H of the wall portion 722 is formed substantially perpendicular to the side surface of the light guide plate 3, and both end surfaces of the resin sealing portion 23x of the linear light source device 2x are opposed to the edge surface 722a. By being formed substantially in parallel, the edge surface 722a and the end surface of the resin sealing portion 23x are fitted to each other, so that it is less likely to be laterally displaced. Accordingly, the linear light source device 2x can be arranged on the case frame 7 with high accuracy.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to the said embodiment. For example, the resin that forms the wall portion 722 is white so that the edge surface 722a functions as a reflecting portion. However, when the wall portion 722 is made of a material having low reflectivity, the reflecting property is reduced. In order to improve this, it is also possible to apply a paint having a white or metallic luster or to attach a seal so that the edge surface 722a functions as a reflecting portion.

  Since the edge surface 722a functions as a reflection part, the reflection part can be omitted in the linear light source devices 2 and 2x. However, even when the reflecting portions 25 are provided on both sides of the resin sealing portion 23y as in the linear light source device 2y shown in FIG. 7, the opening of the wall portion 722y of the case frame 7y shown in FIG. By setting H to a width that allows the reflecting portion 25 to be fitted, it is possible to prevent lateral displacement of the linear light source device 2y.

  In the first and second embodiments, the linear light source devices 2 and 2y are provided with four light source units. However, the number of openings is 1 to 3 or 5 or more. The same effect can be obtained if the wall portion having the is formed in the holding portion.

  In the present invention, since the light emitting device is prevented from being laterally shifted with respect to the light guide plate, it is possible to irradiate the light guide plate with uniform light. It is suitable for a case frame that accommodates a light guide plate that enters from one side surface and exits from a main light emitting surface as illumination light, and a backlight unit using the case frame.

1 is an exploded perspective view of a backlight unit according to Embodiment 1 of the present invention. The top view which shows the linear light source device of the backlight unit shown in FIG. The principal part enlarged view of the case frame which concerns on Embodiment 1 of this invention The principal part enlarged view which shows the state which has arrange | positioned the light-guide plate and the linear light source device to the case frame shown in FIG. The top view which shows the linear light source device which concerns on Embodiment 2 of this invention. The principal part enlarged view which shows the state which has arrange | positioned the linear light source device shown in FIG. 5 in the case frame with the light-guide plate. The top view which shows the linear light source device which concerns on other embodiment The principal part enlarged view which shows the case frame which concerns on other embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Backlight unit 2, 2x, 2y Linear light source device 3 Light guide plate 4 Light control sheet 5 Light-shielding sheet 6 Reflective sheet 7, 7y Case frame 8 Reflective film 9 Adhesive sheet 21 Substrate 22 Light emitting element 23, 23x, 23y Resin sealing Part 24 Printed circuit board 25 Reflection part 41 Diffusion sheet 42 First prism sheet 43 Second prism sheet 71 Base frame part 72 Holding part 721 Floor part 722,722y Wall part 722a Edge surface 723 Abutting part H opening B Solder F Mounting surface R back side

Claims (7)

A holding unit for storing a light emitting device provided with one or more light source units including a light emitting element mounted on a substrate;
In the case frame of the backlight unit in which light from the light source part is incident from one side surface and a frame base part that houses a light guide plate that is emitted from the main light emitting surface as illumination light is formed,
The holding part is located on a floor part on which the substrate is placed in a state where the mounting surface on which the light source unit is mounted is directed to one side surface of the light guide plate, and on the mounting surface side of the substrate, And a wall portion erected on the part,
A case frame of a backlight unit, wherein the wall portion is provided with an opening that fits into a light source portion protruding from the substrate. The case frame of the backlight unit according to claim 1, wherein the holding portion is provided with an abutting portion that abuts against a back surface opposite to the mounting surface of the substrate. The case frame of the backlight unit according to claim 1, wherein a reflection portion that reflects light from the light source portion is provided on an edge surface of the opening of the wall portion. A light emitting device provided with one or more light source units including a light emitting element mounted on a substrate;
A light guide plate from which light from the light source unit is incident from one side surface and emitted from the main light emitting surface as illumination light;
In a backlight unit having a holding unit that stores the light emitting device and a case frame in which a frame base unit that stores the light guide plate is formed.
The case frame holding portion includes a floor portion on which the substrate is placed with a mounting surface on which the light emitting element is mounted facing one side surface of the light guide plate, and a wall portion that is erected on the floor portion. And
The backlight unit according to claim 1, wherein the wall portion is provided with an opening that fits into a resin portion protruding from the substrate. An edge surface of the opening of the wall portion is formed substantially perpendicular to the one side surface of the light guide plate,
The backlight unit according to claim 4, wherein both end surfaces of the light source unit of the light emitting device are formed substantially parallel to the edge surface. The light source part of the light emitting device is formed with a resin sealing part that seals the light emitting element and fits with the opening of the wall part,
The backlight unit according to claim 4, wherein the resin sealing portion is formed in a convex lens shape. The backlight unit according to any one of claims 4 to 6, wherein a reflection portion that reflects light from the light source portion is provided on an opening surface of the wall portion.

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