JP2010102905A - Planar light source, and liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress brightness deterioration in a gap between neighboring side end faces and improve appearance even if a plurality of light guide plates with LED light sources arranged directly under are arranged in a planar light source and a liquid crystal display. <P>SOLUTION: In a plurality of light units each equipped with the LED light source having a light axis directly upward, and the light guide plates 3 directly under which the LED light sources are arranged, and which transform a light path of light incident from the LED light sources and emit the light planarly from the main face 3a side as an upper face, side end faces 3b of the adjacent light guide plates 3 are inclined with respect to the main face 3a, and the guided light is capable of being emitted in the counter direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a planar light source for illuminating a liquid crystal display panel and the like and a liquid crystal display device including the same.

Liquid crystal display devices for image display are widely used for large displays such as thin television devices and thin monitors. This liquid crystal display device uses a backlight unit that emits light from the back side of the liquid crystal display panel to increase the brightness of the display screen.
The backlight unit includes a light guide plate and a light source such as an LED disposed on a side end surface of the light guide plate, guides light from the light source, and emits the light from the entire main surface toward the liquid crystal display panel. ing.

  In recent years, with the increase in size of liquid crystal television devices, there has been a further demand for weight reduction and thickness reduction. It was. In addition, a backlight unit using a light guide plate with a light source on the side edge surface, when an injection molding method is adopted as a method for producing a large light guide plate, when producing a large area and thin type In addition, there is a limit that the resin is difficult to transfer and fill in the entire shape. In addition, in order to sufficiently fill the resin, it may be solved by increasing the molding machine size and increasing the injection pressure. However, since a large molding machine requires a lot of equipment costs, It is difficult to adopt.

  Therefore, conventionally, for example, in Patent Document 1, a plurality of rectangular flat plate-shaped light guide plates arranged adjacent to each other, an LED light source that is installed below the center portion of each light guide plate and emits light upward, An illuminating device having the above has been proposed. Each light guide plate of the illumination device has a light incident prism having a convex shape inwardly in the center portion directly above the LED light source, and light from the LED light source incident from below is reflected on the reflection surface of the light incident prism. The light is guided inside the light guide plate by reflection.

JP 2006-164625 A (FIGS. 1 and 2)

However, the following problems remain in the conventional technology.
Conventionally, when arranging a plurality of light guide plates adjacent to each other, the light guide plates are arranged close to each other. However, in consideration of a fixing method on mounting, an assembly error, a material thickness, thermal expansion, and the like, an interval between adjacent light guide plates Must be set to a certain clearance and the end faces should be abutted against each other. At this time, as in the technique described in Patent Document 1, when the side end surfaces of the adjacent light guide plates are perpendicular to the main surface, the light guided inside is a vertical end surface. Since it is difficult to be reflected from the inside and emitted from the end surface to the outside of the main surface, there is a disadvantage that a gap between adjacent side end surfaces becomes a dark portion. For this reason, a linear brightness | luminance fall part generate | occur | produced between adjacent light-guide plates, and there existed a problem that the appearance deteriorated.

  The present invention has been made in view of the above-described problems, and even if a plurality of light guide plates with LED light sources arranged directly below are arranged, a reduction in luminance in a gap between adjacent side end surfaces can be suppressed and appearance can be improved. An object is to provide a light source and a liquid crystal display device.

  The present invention employs the following configuration in order to solve the above problems. That is, the planar light source of the present invention is a surface from the main surface side that is the upper surface by converting the light source with the light axis directed right above and the light that is incident and guided from the light source. A plurality of light units each having a plurality of light units, arranged in a plurality of rows with the light guide plates adjacent to each other, and side end surfaces of the light guide plates adjacent to each other. However, it is inclined with respect to the main surface, and the guided light can be emitted in the opposite direction.

  In this planar light source, the side end surfaces of the light guide plates adjacent to each other are inclined with respect to the main surface, and the guided light can be emitted in the opposite direction. Light is emitted obliquely, and the brightness in the gap between the side end faces is improved. Therefore, the brightness in the vicinity of the adjacent side end faces is corrected to suppress a reduction in brightness, and the overall appearance is improved. In addition, since the brightness between the light guide plates is improved, the distance between the light guide plates can be set wider than before, and a design with a margin in consideration of the fixing method, assembly error, material thickness, thermal expansion, etc. is possible. Become.

  Further, the planar light source of the present invention is formed with a reflecting concave portion formed on the main surface of the light guide plate and immediately above the light source, which is gradually formed deeper toward the optical axis of the light source and the surface is inclined. It is characterized by being. That is, in this planar light source, since the main surface of the light guide plate is directly above the light source, a reflecting recess is formed which is gradually formed deeper toward the optical axis of the light source and the surface becomes an inclined surface. The light emitted directly from the light source and incident on the light guide plate is reflected by the inclined surface of the reflecting recess directly above, and the optical path is changed toward the side end face. Therefore, the light incident from directly below the light guide plate is reflected to the surroundings by the reflection concave portion, so that the light is spread to the surroundings to guide the inside of the light guide plate, so that the generation of so-called hot spots directly above the light source is suppressed, and the luminance Uniformity can be improved.

  The planar light source of the present invention is characterized in that a fine optical shape portion is formed on the lower surface of the light guide plate to reflect, refract, or diffuse the light guided inside to the main surface side. . That is, in this planar light source, a fine optical shape portion that reflects, refracts, or diffuses light guided inside is formed on the lower surface of the light guide plate. It is possible to suppress the emission of light from the outside to the outside and efficiently guide the light guided inside to the main surface side, thereby improving the overall luminance.

  Further, the planar light source of the present invention is characterized in that a storage recess for storing the light source is formed on the lower surface of the light guide plate, and the light source is installed in the storage recess. That is, in this planar light source, since the light source is installed in the concave portion for storage formed on the lower surface of the light guide plate, it becomes possible to reduce the overall thickness by at least the height of the light source, It becomes possible to mount the light guide plate directly on the lower reflection sheet or the like. Further, not only the direction directly above the light source but also the light emitted to the surroundings can efficiently enter the light guide plate from the concave portion for storage, and the luminance can be improved.

  The planar light source according to the present invention is characterized in that the light guide plate has a square shape and is arranged in a matrix having a plurality of columns and rows. That is, in this planar light source, since the light guide plate is formed in a square shape and arranged in a matrix shape composed of a plurality of columns and rows, so-called local brightness control is performed by partial luminance control for partially driving the light source for each light guide plate. Dimming can be implemented easily. For example, as local dimming, the backlight brightness is controlled according to the brightness and contrast of the image displayed on the liquid crystal display panel, and the backlight brightness is controlled based on the image data input to the liquid crystal display panel. By adjusting the brightness by controlling the location and time each time, it is possible to reduce power consumption and improve the contrast, moving image followability, and the like.

  The liquid crystal display device of the present invention comprises a liquid crystal display panel and the planar light source of the present invention disposed on the back side of the liquid crystal display panel. That is, in this liquid crystal display device, that is, in this liquid crystal display device, since the planar light source of the present invention is provided, a decrease in luminance between light guide plates arranged directly below the light source is suppressed, and the appearance is large. An image display of the area is obtained.

The present invention has the following effects.
That is, according to the planar light source according to the present invention, the side end surfaces of the light guide plates adjacent to each other are inclined with respect to the main surface, and the guided light can be emitted in the opposite direction. Light is emitted obliquely from the end face toward the opposite direction, a reduction in luminance in the gap between the side end faces is suppressed, and the overall appearance is improved.
Therefore, by installing multiple small-sized light guide plates that do not require a large molding machine or mold processing and can be manufactured easily and at low cost, large sizes can be realized, and the brightness of the adjacent light guide plate edge can be reduced. It is possible to obtain a planar light source which is suppressed and has a good appearance. Moreover, according to the liquid crystal display device provided with this planar light source, it is possible to obtain a large-area image display with a good appearance.

  Hereinafter, a planar light source and a liquid crystal display device according to a first embodiment of the present invention will be described with reference to FIGS. In each drawing used in the following description, the scale is appropriately changed to make each member a recognizable size.

  The planar light source 1 in the present embodiment is a backlight unit of a liquid crystal display device, and as shown in FIGS. 1 to 3, an LED light source (light source) 2 having an optical axis 2a directed upward, and the LED A plurality of light units each including a light source plate 3 disposed immediately below the central portion, and a light guide plate 3 configured to change the optical path of the light incident and guided from the LED light source 2 and to emit the light from the main surface 3a side which is the upper surface. 4 are arranged in a plurality of rows with the light guide plates 3 adjacent to each other.

  The light guide plate 3 has a square shape in a top view and is arranged in a matrix shape including a plurality of columns and rows. In this embodiment, the long side direction is a horizontal row and the short side direction is a vertical row, and the light units 4 are arranged in 8 vertical rows and 4 horizontal rows. The shape of the light guide plate 3 and the number of installed light guide plates 3 may be determined so that the main aspect ratio is 16: 9 with a large-sized backlight.

The four side end surfaces 3b of the light guide plates 3 adjacent to each other are inclined with respect to the main surface 3a, and the guided light can be emitted in the opposite direction. That is, in this embodiment, the four side end surfaces 3b of the light guide plate 3 are all inclined toward the main surface 3a side, and light can be emitted obliquely upward toward the main surface 3a side. Yes. In addition, the inclination angle with respect to the main surface 3a of these side end surfaces 3b is determined according to the brightness | luminance between the adjacent side end surfaces 3b so that the light guided inside may be emitted outside efficiently. For example, the inclination angle of the side end face 3b is set to 45 ° or the like.
In addition, a reflective recess 3c is formed on the main surface 3a of the light guide plate 3 directly above the LED light source 2 and gradually formed deeper toward the optical axis 2a of the LED light source 2 so that the surface is inclined. Yes. That is, the reflecting recess 3c has a circular cross-sectional shape, a mortar shape or a substantially inverted conical shape, and an inclined surface of the surface is a quadratic curved surface. Moreover, you may provide the unevenness | corrugation which makes it easy to reflect, scatter, or radiate | emit by printing etc. in the recessed part 3c for reflection.

  Further, on the lower surface of the light guide plate 3, except for the portion directly above the LED light source 2, there is formed a fine optical shape portion 3d that reflects, refracts, or diffuses light guiding the inside toward the main surface 3a side. As the fine optical shape portion 3d, a prism shape portion constituted by a plurality of groove portions, ridge portions, or the like, a large number of dot shape portions formed by dot printing, or the like can be employed.

The light guide plate 3 is made of, for example, transparent polycarbonate resin or acrylic resin.
The light guide plate 3 is installed at a predetermined distance above the rigid substrate 5 while being fixed to a bezel (not shown), for example. The light guide plate 3 may be fixed by providing a pin on the lower surface of the light guide plate 3 and inserting the pin into a hole provided in the rigid substrate 5.
These adjacent light guide plates 3 are arranged apart from each other by a distance of several millimeters according to assembly errors, luminance near the side end surface 3b, and appearance.
Each LED light source 2 is installed on a rigid board 5 and connected to a flexible printed board (not shown).

  The LED light source 2 is a white LED installed with the optical axis 2a set vertically upward and the light emitting surface facing upward. This white LED is, for example, a semiconductor light emitting element on a substrate sealed with a resin material. As the semiconductor light emitting element, for example, a blue (wavelength λ: 470 to 490 nm) LED element or ultraviolet light (wavelength λ: less than 470 nm). An LED element is formed by laminating a plurality of semiconductor layers of a gallium nitride compound semiconductor (for example, an InGaN compound semiconductor) on an insulating substrate such as a sapphire substrate.

  Further, the resin material for sealing the semiconductor light emitting element is mainly composed of a silicone resin and, for example, a YAG phosphor is added. This YAG phosphor converts white light or ultraviolet light from a semiconductor light emitting element into yellow light and generates white light by a color mixing effect. The LED light source 2 has a reflective frame formed on the side of the resin material other than the tip surface so that light is emitted only from the tip surface. As the white LED, various types other than the above can be adopted.

  Further, the liquid crystal display device 10 of the present embodiment is a display device applied to a liquid crystal display such as a large liquid crystal television device, for example. As shown in FIG. 3, the liquid crystal display panel 11 and the liquid crystal display panel 11 And the planar light source 1 disposed on the back side.

That is, the liquid crystal display device 10 is arranged on the planar light source 1 composed of the plurality of light units 4 and the plurality of light guide plates 3 arranged, and diffuses the light from the light guide plates 3 to achieve in-plane light intensity. Diffusing plate 12A for uniforming, diffusing sheet 12B disposed on the diffusing plate 12A, and upward irradiation light directed to the liquid crystal display panel 11 from the diffusing sheet 12B disposed on the diffusing sheet 12B And the liquid crystal display panel 11 disposed on the prism sheet 13, and the reflection sheet 14 disposed below the light guide plate 3.
In the present embodiment, the screen side of the liquid crystal display panel 11 and the light emission surface (main surface 3a) side of the planar light source 1 are described as the surface side or the upper surface side.

The diffusion plate 12A and the diffusion sheet 12B are, for example, plates and sheets in which silica particles or the like are dispersed in a transparent resin such as an acrylic resin or a polycarbonate resin.
The prism sheet 13 is a transparent sheet-like member for condensing light from the diffusion sheet 12B on the upper surface side, and has a prism portion having a plurality of parallel ridge lines on the upper surface side.

  The reflection sheet 14 is a metal plate, film, foil or the like having a light reflection function, and a film provided with a silver vapor deposition film is employed in the present embodiment. Note that an aluminum metal vapor deposition film or the like may be employed instead of the silver vapor deposition film. The reflection sheet 14 may be a white sheet. The reflection sheet 14 is affixed on the bezel or the rigid substrate 5 by a double-sided tape (not shown) except for the portion where the LED light source 2 is placed.

  The liquid crystal display panel 11 is a transmissive or transflective liquid crystal display panel. For example, in the case of the transmissive liquid crystal display panel 11, a TFT liquid crystal method, an STN liquid crystal method, or a TN device in which a liquid crystal material is sealed in a gap between an upper substrate and a lower substrate each having a transparent electrode, an alignment film, and a polarizing plate. A panel body such as a liquid crystal system is provided.

  As described above, in the planar light source 1 according to the embodiment, the side end surfaces 3b of the light guide plates 3 adjacent to each other are inclined with respect to the main surface 3a, and the guided light is emitted in the opposite direction (main surface 3a side). Therefore, light is emitted obliquely from the side end surface 3b toward the opposite direction, and the luminance in the gap between the side end surfaces 3b is improved. Therefore, the brightness in the vicinity of the adjacent side end face 3b is corrected, the reduction in brightness is suppressed, and the overall appearance is improved. In addition, since the brightness between the light guide plates 3 is improved, the interval between the light guide plates 3 can be set wider than before, and a design with a margin in consideration of the fixing method, assembly error, material thickness, thermal expansion, etc. It becomes possible.

  Further, a reflective recess 3c is formed on the main surface 3a of the light guide plate 3 directly above the LED light source 2 and gradually formed deeper toward the optical axis 2a of the LED light source 2 and the surface thereof becomes an inclined surface. Therefore, the light emitted directly from the LED light source 2 and entering the light guide plate 3 is reflected by the inclined surface of the reflection recess 3c directly above, and the optical path is changed toward the side end face 3b. Therefore, the light incident from directly below the light guide plate 3 is reflected to the surroundings by the reflecting recess 3c, so that the light is spread to the surroundings and guided in the light guide plate 3 to generate a so-called hot spot directly above the LED light source 2. In addition to the suppression, the luminance uniformity can be improved.

  Furthermore, since the fine optical shape portion 3d that reflects, refracts, or diffuses the light guided through the inside to the main surface 3a side is formed on the lower surface of the light guide plate 3, the fine optical shape portion 3d externally It is possible to improve the overall luminance by suppressing the emission of light to the main surface and efficiently guiding the light guided inside to the main surface 3a side.

  In addition, since the light guide plate 3 has a square shape and is arranged in a matrix having a plurality of columns and rows, so-called local dimming is performed by partial luminance control that partially drives the LED light source 2 for each light guide plate 3. It can be easily implemented. For example, as local dimming, the luminance of the backlight is controlled according to the luminance and contrast of the image displayed on the liquid crystal display panel 11, and the luminance of the backlight is adjusted based on the image data input to the liquid crystal display panel 11. By adjusting the brightness by controlling the location of each light guide plate 3 in terms of location and time, it is possible to reduce power consumption and improve contrast, moving image followability, and the like.

  Therefore, in the liquid crystal display device 10 that employs the planar light source 1 as a backlight unit, a decrease in luminance between the light guide plates 3 is suppressed, and a large-area image display with good appearance can be obtained.

  Next, second to fifth embodiments of the planar light source and the liquid crystal display device according to the present invention will be described below with reference to FIGS. In the following description of each embodiment, the same constituent elements described in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The difference between the second embodiment and the first embodiment is that, in the first embodiment, the light guide plate 3 has a square shape in a top view, whereas in the planar light source 21 of the second embodiment, FIG. As shown in FIG. 5, the light guide plate 23 of the light unit 24 has a regular hexagonal shape when viewed from above. That is, the light guide plate 23 of the second embodiment has six side end surfaces 23b, and the light guide plates 23 adjacent to each other are arranged in a honeycomb shape with the side end surfaces 23b facing each other.

  Therefore, also in the planar light source 21 of the second embodiment, as in the first embodiment, the six side end surfaces 23b of the light guide plates 23 adjacent to each other are inclined toward the main surface 23a side. Light is easily emitted from the end surface 23b to the outside on the main surface 23a side, and the luminance in the gap between the side end surfaces 23b is improved.

  The difference between the third embodiment and the first embodiment is that, in the first embodiment, the LED light source 2 is arranged immediately below the center of the lower surface, which is the plane of the light guide plate 3, whereas the third embodiment. In the planar light source 31, as shown in FIG. 6, a housing recess 33 e for housing the LED light source 2 is formed at the center of the lower surface of the light guide plate 33, and the LED light source 2 is installed in the housing recess 33 e. It is a point. That is, in the third embodiment, a housing recess 33e is formed on the lower surface of the central portion of the light guide plate 33 in a shape that can accommodate the LED light source 2 corresponding to the outer shape of the LED light source 2. The light guide plate 33 is also different from the first embodiment in that the light guide plate 33 is directly placed on the reflection sheet 14.

Therefore, in the planar light source 31 of the third embodiment, since the LED light source 2 is installed in the housing recess 33e formed on the lower surface of the light guide plate 33, the overall thickness is at least the height of the LED light source 2. It is possible to reduce the thickness, and it is possible to directly mount the light guide plate 33 on the lower reflection sheet 14 or the like. Further, not only the direction directly above the LED light source 2 but also the light emitted to the periphery such as the direction orthogonal to the optical axis 2a can be efficiently incident into the light guide plate 33 from the housing recess 33e, thereby improving the luminance. Can be planned.
The inner surface shape of the storage recess 33e may be an inclined surface or a curved surface that allows the light incident from the LED light source 2 to change the optical path from the direction directly above to the side end surface 3b.

  The difference between the fourth embodiment and the first embodiment is that, in the first embodiment, the four side end surfaces 3b of the light guide plates 3 adjacent to each other are inclined toward the main surface 3a side. On the other hand, in the light guide plate 43 of the fourth embodiment, as shown in FIG. 7, the four side end surfaces 43b are all inclined toward the lower surface side opposite to the main surface 3a.

That is, in the planar light source 41 of the fourth embodiment, the side end surfaces 43b of the adjacent light guide plates 43 are arranged toward the reflection sheet 14 on the side opposite to the main surface 3a.
Therefore, in the fourth embodiment, the side end face 43b of the adjacent light guide plate 43 is directed to the opposite side of the main surface 3a, and the reflection sheet 14 is provided on the opposite side of the main surface 3a of the light guide plate 43. The light emitted obliquely downward from the side end surface 43b of the light guide plate 43 is reflected to the main surface 3a side by the reflection sheet 14, so that the luminance between the adjacent side end surfaces 43b can be increased.

  The difference between the fifth embodiment and the fourth embodiment is that, in the fourth embodiment, the same light guide plate 43 in which the side end surface 43b is arranged toward the reflection sheet 14 on the opposite side to the main surface 3a is arranged. On the other hand, in the planar light source 51 of the fifth embodiment, as shown in FIG. 8, the light guide plates 3 in the light unit 4 of the first embodiment and the light guide plates 43 in the fourth embodiment are alternately adjacent. It is a point that is arranged.

  That is, in the planar light source 51 of the fifth embodiment, the side end surface 3b of the light guide plate 3 is directed to the main surface 3a side at the side end surface 3b of the light guide plate 3 and the side end surface 43b of the light guide plate 43 that are adjacent to each other. In addition, the side end surface 43b of the light guide plate 43 is directed to the opposite side of the main surface 3a and is disposed above the side end surface 3b of the light guide plate 3. Therefore, the side end face 3b of the adjacent light guide plate 3 and the side end face 43b of the light guide plate 43 are in an opposed state with mutually parallel inclined surfaces.

  Thus, in the planar light source 51 of the fifth embodiment, the side end surface 3b of the light guide plate 3 is directed to the main surface 3a side, and the side end surface 43b of the light guide plate 43 is on the side opposite to the main surface 3a. Since it is directed and disposed above the side end surface 3b of the light guide plate 3, the side end surface 3b of the light guide plate 3 and the side end surface 43b of the light guide plate 43 overlap in a plan view viewed from the main surface 3a side. In this state, the light emitted from both side end faces 3b and 43b is also overlapped, and the luminance between the side end faces 3b and 43b can be improved.

  In addition, this invention is not limited to said each embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.

For example, in each of the above embodiments, a light guide plate having a square shape or a regular hexagonal shape is used in a top view, but a light guide plate formed in another shape such as a rectangular shape or a triangular shape may be used.
In addition, although one LED light source is installed immediately below the center of the lower surface of each light guide plate, a plurality of LED light sources may be installed immediately below the lower surface of each light guide plate.
In addition, a fine optical shape part such as a prism shape is formed on the lower surface of the light guide plate, but the light that guides the inside is also refracted on the upper surface of the light guide plate to change the optical path and emit it. A fine optical shape portion may be formed. For example, a lenticular lens shape portion composed of a plurality of fine kamaboko convex lenses may be formed on the upper surface of the light guide plate as the fine optical shape portion.

In addition, it is possible to emit light of any color using RGB-LEDs as LED light sources. For example, as an RGB-LED, an LED in which a red LED element (R), a green LED element (G), and a blue LED element (B) are mounted in one package is used as a light source, or one light guide plate emits light from each other. Different LED light sources may be arranged. In these cases, by controlling the applied current in each LED, it becomes possible to illuminate with light of various colors for the entire planar light source or for each light unit.
In addition, although the LED light source was employ | adopted as a light source, you may employ | adopt other light sources, such as a fluorescent tube.

  In the backlight unit of each of the embodiments described above, one diffusion plate and one diffusion sheet are used, but either one may be omitted, or a backlight unit using a plurality of at least one may be used. Further, the diffusion plate or the diffusion sheet may be a backlight unit arranged between the prism sheet and the liquid crystal display panel. That is, for the brightness unevenness adjustment, the installation positions and the number of sheets are appropriately set in consideration of the number and haze of these diffusion plates and diffusion sheets.

In addition, although one prism sheet is used, a backlight unit employing two prism sheets may be used.
In each of the above embodiments, a diffusion plate, a diffusion sheet, and a prism sheet having a size corresponding to the size of the liquid crystal display panel are employed, but these are divided into a plurality of light guide plates and arranged side by side. You may employ | adopt the structure to do.

FIG. 3 is a plan view showing a planar light source in the planar light source and the liquid crystal display device according to the first embodiment of the present invention. In 1st Embodiment, it is the top view and side view which show a light-guide plate. In 1st Embodiment, it is an expanded longitudinal cross-sectional view of the principal part which shows the liquid crystal display device except a bezel. It is a top view which shows a planar light source in 2nd Embodiment of the planar light source and liquid crystal display device which concern on this invention. In 2nd Embodiment, it is the top view and side view which show a light-guide plate. In 3rd Embodiment of the planar light source and liquid crystal display device which concern on this invention, it is an expanded longitudinal cross-sectional view of the principal part which shows the liquid crystal display device except a bezel. In 4th Embodiment of the planar light source and liquid crystal display device which concern on this invention, it is an expanded longitudinal cross-sectional view of the principal part which shows the liquid crystal display device except a bezel. In 5th Embodiment of the planar light source and liquid crystal display device which concern on this invention, it is an expanded longitudinal cross-sectional view of the principal part which shows the liquid crystal display device except a bezel.

Explanation of symbols

  1, 2, 31, 41, 51... Planar light source, 2... LED light source (light source), 2 a... Optical axis of LED light source, 3, 23, 33, 43. 3b, 23b, 43b ... side end face of the light guide plate, 3c ... reflective recess, 3d ... fine optical shape part, 4 ... light unit, 10 ... liquid crystal display device, 11 ... liquid crystal display panel, 12A ... diffusion plate, 12B ... Diffusion sheet, 13 ... Prism sheet, 14 ... Reflection sheet, 33e ... Recess for storage

Claims (6)

A light source with the optical axis directed right above,
A plurality of light units each including the light source plate, the light guide plate including a light source plate disposed immediately below and light-guided and guided from the light source to emit light in a plane form from a main surface side that is an upper surface. Is a planar light source composed of a plurality of rows arranged adjacent to each other,
A planar light source characterized in that side end surfaces of the light guide plates adjacent to each other are inclined with respect to the main surface, and the guided light can be emitted in a facing direction. The planar light source according to claim 1,
A planar shape characterized in that a reflecting concave portion is formed on the main surface of the light guide plate and immediately above the light source, the reflection concave portion being formed gradually deeper toward the optical axis of the light source and having an inclined surface. light source. The planar light source according to claim 1 or 2,
A planar light source characterized in that a fine optical shape portion is formed on the lower surface of the light guide plate to reflect, refract, or diffuse light guided inside to the main surface side. In the planar light source according to any one of claims 1 to 3,
A recess for storing the light source is formed on the lower surface of the light guide plate,
A planar light source, wherein the light source is installed in the housing recess. In the planar light source according to any one of claims 1 to 4,
A planar light source characterized in that the light guide plate has a square shape and is arranged in a matrix having a plurality of columns and rows. A liquid crystal display panel;
A liquid crystal display device comprising: the planar light source according to any one of claims 1 to 5 disposed on a back surface side of the liquid crystal display panel.

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