JP2010287556A - Lighting device and display including the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting device that achieves uniform luminance by preventing emission lines caused by outgoing light of an oblique component leaked from a gap of each overlapped part in the lighting device in which a plurality of light-guide bodies are arrayed in a planar shape by providing each overlapped part. <P>SOLUTION: It is configured to use the light-guide body that emits much light having a component vertical to a light outgoing surface. A light-incident part 2e of the light-guide body 2 is composed of a light-incident surface provided with each recess 2f, and a paraboloid 2g formed on a parabola in a light-outgoing direction from a light-outgoing part of a light source 1. By this, light vertically hits a reflective structure provided on a lower surface of the light-guide body, thereby allowing vertical outgoing light to be emitted from the light-outgoing surface. Alternatively, a plurality of concave micro-prisms are formed on the lower surface of the light-guide body and arranged such that a bottom face of a reflecting surface of each micro-prism becomes vertical to an optical path of light from the light source. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a flat backlight device used for illuminating a liquid crystal display device or the like from the back and a liquid crystal display device using the same.

  A liquid crystal display device composed of a liquid crystal display panel and a flat backlight arranged on the back surface of the liquid crystal display panel is widely used. In recent years, with the increase in size of liquid crystal display panels, the size of flat backlights has also been increasing. Functions required for a large flat backlight include high brightness and uniform brightness over the entire light emitting surface, being thin and lightweight, and suppressing an increase in manufacturing cost. In particular, the increase in the size of the constituent members increases the assembly line, increases the capital investment, and increases the manufacturing cost when defective products occur.

  Conventionally, a structure in which divided portions of a light guide divided in parallel to a line light source are bonded with an adhesive or a structure in which a plurality of adjacent light guides are arranged in a planar shape is known ( For example, see Patent Document 1 or Patent Document 2.)

Japanese Patent Laid-Open No. 5-158035 JP 2008-192395 A

  In the conventional lighting device in which the divided portions of the light guide are connected with an adhesive, when a defect such as a scratch or a dirt is found, the entire connected light guide must be replaced. There was a problem that it was not possible to make use of the advantage of dividing. Further, there is a problem that light is reflected at the interface connected by the adhesive and uniform light is not emitted.

  In contrast, there has been proposed an illuminating device in which a plurality of light guides are arranged in a planar shape so that a light source part of a light guide and an end part of an adjacent light guide overlap. However, since the light is diffused and emitted from the emission surface of the light guide, the emitted light contains a large amount of light components in the oblique direction. For this reason, light leaks obliquely from the gap between the overlapping portions of the light guide end and the light incident portion, and a bright line is generated at the connection portion of the adjacent light guide to prevent uniform surface light emission. occured.

  Therefore, an object of the present invention is to realize an illumination device and a display device that can emit uniform light and can be enlarged.

  In order to solve the above-described problem, in the lighting device of the present invention, a plurality of adjacent light guides are arranged in a plane with overlapping portions, and the light guide is perpendicular to the light guide exit surface. A structure that emits a large amount of light of various components is adopted. In the overlapping part of the plurality of light guides, the upper surface of the light incident part of the light guide and the upper surface of the light source corresponding to the light incident part are arranged so as to overlap the end part of the other adjacent light guides. The Furthermore, in the overlapping part of the light guide, a light shielding film for preventing light leakage is disposed so as to cover the upper surfaces of the light source and the light incident part.

  According to the present invention, by arranging a plurality of light guides that emit a large amount of light in a component perpendicular to the light exit surface of the light guide, high brightness can be achieved without generating bright lines at the connection part of the light guide. In addition, uniform illumination light can be obtained. In addition, since a plurality of light guides are arranged, when a defect occurs, only the light guide including the defect needs to be replaced, and the manufacturing cost can be reduced.

It is a schematic diagram which shows the structure of the illuminating device of this invention. It is a schematic diagram which shows the cross section of the illuminating device of this invention. It is an enlarged view explaining the light-incidence part of the illuminating device of this invention. It is a schematic diagram which shows the cross-sectional structure of the illuminating device of this invention. It is a schematic diagram which shows a part of structure of the illuminating device of this invention. It is a schematic diagram which shows a part of structure of the illuminating device of this invention. It is a schematic diagram which shows the cross-sectional structure of the display apparatus of this invention. It is a schematic diagram which shows the structure of the illuminating device of this invention. It is a schematic diagram which shows a part of structure of the illuminating device of this invention. It is a schematic diagram which shows an example of a structure of the microprism of this invention. It is a schematic diagram which shows the cross-sectional structure of the illuminating device of this invention. It is an enlarged view explaining the light-incidence part of the illuminating device of this invention.

  The lighting device of the present invention has a configuration in which a plurality of adjacent light guides are arranged in a plane with overlapping portions, and each light guide introduces light from a light source into a light incident portion. The light is emitted in the vertical direction. The light guide has a light incident part facing the light source and an end opposite to the light incident part. The upper surface of the light incident part and the upper surface of the light source facing the light incident part are adjacent to each other. It arranges so that it may overlap with the edge of a light body. A light-shielding film may be provided at the place where the light guides overlap (overlapping part) so as to cover the light source and the light incident part, thereby blocking the light.

  Furthermore, the light incident part of the light guide has a light incident surface facing the light output part of the light source and a parabolic surface formed in a parabolic shape in the light output direction of the light source. A concave portion is formed on the light incident surface. Further, a reflective structure is provided on the lower surface on the back side of the exit surface of the light guide. With such a configuration, the light from the light source is aligned in the light incident portion and reflected when perpendicular to the reflecting structure, and thus is emitted in a direction perpendicular to the emission surface.

  Alternatively, a plurality of concave microprisms having one reflecting surface that reflects light from the light source and a plurality of other side surfaces may be formed on the lower surface of the light guide. The base of the reflecting surface of the microprism is disposed at an angle of approximately 90 degrees with respect to the optical path of any one of the plurality of light sources, and the base of the side surface is other than 90 degrees with respect to the optical paths of the plurality of light sources. Arranged at an angle. With such a configuration, the light from the light source is reflected perpendicularly to the reflection surface of each microprism, and is emitted in a direction perpendicular to the emission surface.

  The display device of the present invention is configured to illuminate a non-self-luminous display element with the illumination device having any one of the above-described configurations.

  The illumination device of the present embodiment will be described with reference to FIGS. FIG. 1 is a top view of the illumination device of the present embodiment. As shown in FIG. 1, the illuminating device of a present Example is provided with the light source 1 and several light guides 2a-2d arranged adjacent to planar shape. Each of these light guides 2a to 2d has basically the same shape and configuration, and guides the light of the light source 1 from the light incident part 2e to emit light from the emission surface. Although not shown, the light incident portion of the light guide 2a, the light incident portion of the light guide 2c, and the light sources corresponding to these light incident portions are the back surfaces of the end portions of the light guide 2b and the light guide 2d, respectively. It is arranged to overlap. Each light guide is formed with a reflecting structure such as a prism or a dot. The light that has entered each light guide is emitted from the exit surface by being directed to the reflecting structure while being guided.

  FIG. 2 is a cross-sectional view of the illumination device of the present embodiment. As shown in the figure, a light guide 2 a that guides light from the light source 1 and emits a large amount of light having a component perpendicular to the emission surface, and a light guide 2 b are housed in a frame 7. The light guide 2a and the light guide 2b are arranged so that the end of the light guide 2b overlaps the light incident part of the light guide 2a and the light source facing the light incident part. In the overlapping part of the light guide 2a and the light guide 2b, the light shielding film 6 is disposed so as to cover the light incident part of the light guide 2a and the light source facing the light incident part. A reflection sheet 4 is disposed between the lower surface of the light guide 2 a and the light guide 2 b and the frame 7.

  In FIG. 3, the shape of the light incident part 2e of the light guide 2 is enlarged and shown. As shown in the drawing, a trapezoidal concave portion 2 f is provided on the light incident surface facing the light source 1. The short side of the trapezoid is 0.2 to 0.6 mm, the long side is about 1.0 to 1.2 mm, the height is about 0.5 to 1.0 mm, and the optimum value depends on the light distribution characteristics of the light source 1 and the like. . In addition, a parabolic surface 2g extends in a parabolic shape from the light output portion of the light source 1 along the light output direction. The curve of the paraboloid 2g is determined by the focal position of the parabola that forms the paraboloid 2g, and the focal position is in the range of approximately 0.5 to 0.7 mm horizontally from the light source 1 along the emission surface. The shape of the recess, the parabola and the focal position thereof are optimized according to the light distribution characteristics of the light source 1. In this embodiment, the concave shape is trapezoidal, but the same effect can be obtained even if the shape is a semicircle, a triangle, or a polygon.

  Reflective structures such as prisms and dots are formed on the exit surface and bottom surface of the light guide 2. The light that has entered the light guide 2 travels while guiding the inside of the light guide, and exits from the exit surface of the light guide 2 by hitting the reflection structure. The light incident part 2e of the present embodiment causes more light components that exit perpendicularly from the exit surface (in other words, toward the observer) to enter the light guide when hitting the reflecting structure. Can do. The light incident portion 2e has a function of converting the direction of some components while dividing the light of the light source 1 into three directions. The light emitted from the light source 1 collides with the trapezoidal concave portion 2f, enters the light guide 2 from the short side of the trapezoid, and refracts from the two oblique sides of the trapezoid, and the linear component 3a that travels almost linearly. It is divided into components that enter light. This component hits the paraboloid 2g, and many of the components are totally reflected to become the reflection component 3b, and travel in substantially the same direction as the straight component 3a. That is, by providing the trapezoidal concave portion 2f and the parabolic surface 2g on the light incident surface of the light incident portion, the direction of light from the light source 1 can be aligned. The focal length of the paraboloid 2g is about 0.5 to 0.7 mm from the light source 1. The light of the rectilinear component 3a and the reflection component 3b hits the reflection structure formed on the light guide 2 and is emitted from the emission surface. In this embodiment, the paraboloid 2g is a curved surface. However, the paraboloid 2g may be formed by a plurality of planes combined at an angle to have a polygonal shape. When the paraboloid 2g has a polygonal shape, the light distribution of the lighting device can be easily controlled.

  Next, FIG. 4 schematically shows a main part of an illumination device in which a lower prism is formed on the lower surface of the light guide as a reflective structure. Since the above-described light incident portion 2 e is formed in the light guide 2, most of the light emitted from the light source 1 is a component perpendicular to the lower prism 5. Light in a direction perpendicular to the top line of the lower prism 5 is reflected by the lower prism 5 and is emitted perpendicularly from the emission surface. Therefore, the light output efficiency from the light guide can be made extremely high.

  FIG. 5 schematically shows a cross-sectional configuration of the illumination device having the light guide 2 on which the lower prism 5 is formed. The light guide 2 has an exit surface 2e and a facing surface, and a reflection sheet 4 is installed below the facing surface. The reflection sheet 4 is often a type in which silver or aluminum is vapor-deposited on a transparent film such as PET, white PET, ESR manufactured by Sumitomo 3M, or the like.

  The lower prism 5 is a recess formed on the lower surface of the light guide 2 and is composed of at least two surfaces. Of these two surfaces, the surface close to the light source 1 is the reflecting surface 2i. As described above, the light incident on the light guide 2 from the light source 1 is divided into the straight component 3a and the reflection component 3b, and hits the lower prism 5 perpendicular to the top line of the lower prism 5. Therefore, many components are easily emitted from the emission surface 2h. Further, if the prism angle (the angle formed by the reflecting surface 2i of the lower prism 5 and the exit surface 2h of the light guide) is in the range of 40 to 50 degrees, many components are reflected on the reflecting surface 2i of the lower prism 5 and the light guide. 2 is totally reflected in the direction perpendicular to the exit surface 2h. In this embodiment, the pitch of the lower prism 5 is set to be equal and the height is changed. The lower the prism 5 is, the lower the distance from the light source 1, and the higher the distance from the light source 1. When used in combination with a light guide formed with a prism and a liquid crystal panel, there may be a prism pitch that easily interferes with the dot pitch of the liquid crystal panel. If the pitch is constant as in this embodiment, there is an advantage that it is easy to avoid interference with the liquid crystal panel.

  On the other hand, when the surface farther from the light source 1 among the surfaces constituting the lower prism 5 is referred to as an inclined surface, the inclined surface does not contribute much to the light emitted from the light guide 2. Therefore, emphasizing the manufacture of the mold, the angle between the inclined surface of the prism and the light exit surface of the light guide is made smooth, and the bottom of the reflecting surface of the lower lower prism and the base of the inclined surface of the lower lower prism are in contact with each other. You may form as follows. By adopting such a shape, the mold is neither convex nor concave and is easy to manufacture. Further, the mold can be manufactured by a conventional machining technique, and the size can be easily increased.

  Further, when the height of the lower prism 5 must be very small depending on the thickness and size of the light guide 2, the height of the lower prism is constant, and the pitch is narrowed as the distance from the light source 1 increases. Even if it is such a structure, the same effect can be acquired.

  Next, a configuration in which a prism is formed on the exit surface of the light guide 2 is schematically shown in FIG. As shown in the drawing, an upper prism 8 having an arrangement direction orthogonal to the arrangement direction of the lower prism 5 is formed on the exit surface of the light guide 2. By forming the upper prism 8 as described above, light unevenness and the like can be reduced. As shown in the figure, a triangular prism is used as the upper prism 8. The apex angle of the upper prism may be set in a wide range of 40 ° to 170 °. Basically, high brightness can be aimed at increasing the apex angle, and wide viewing angle can be aimed at reducing the apex angle. In addition, by arranging a plurality of upper prisms 8 instead of a single apex angle, light is scattered at various angles, which is effective in reducing unevenness. At this time, the upper prism 8 is formed not only on the entire surface of the light emitting portion of the light guide 2 but also on the upper surface of the light incident portion 2e. It is desirable to form as close to the light source 1 as possible. By forming the upper prism 8 up to the upper surface of the light incident part 2e, the linear component 3a and the reflection component 3b can be mixed more uniformly. The optimum value of the top prism apex angle for uniformly mixing the straight component 3a and the reflection component 3b is often different from the optimum value of the top prism apex angle for reducing unevenness on the light guide 2. It is more preferable to individually optimize the upper prism shape provided on the upper surface of the light portion 2e (the light guide 2 near the light source 1) and the upper prism shape provided on the light emitting portion of the light guide 2. That is, the apex angle of the prism formed on the upper surface of the light incident part near the light source is set so as to align the direction of the light emitted from the light incident part, and the apex angle of the prism formed on the upper surface of the light emitting part is the output surface It is set so as to reduce the unevenness. In this embodiment, the upper prism 8 is a triangular prism, but it may be a semicircular prism. In the case of a semicircular prism, the direction in which light scatters is not stepwise as compared to a triangular prism, and the unevenness may be further reduced. In addition, the upper prism does not need to be formed in parallel with the outgoing direction of the light source, and may be formed to have two kinds of angles with respect to the outgoing direction of the light source 1.

  FIG. 7 is a cross-sectional view of a display device provided with the illumination device of this embodiment. The light from the light source 1 enters the light guide 2 and is emitted from the exit surface by the lower prism provided on the light guide 2 to illuminate the liquid crystal panel 11. By covering the light guide 2 with the frame 7, a display with very high luminance can be realized. Here, the diffusion film 9 is disposed on the light guide 2, and the BEF sheet manufactured by Sumitomo 3M or the prism sheet 10 manufactured by Mitsubishi Rayon is disposed on the diffusion film 9, but this is not an essential component. A plurality of diffusion films 8 and prism films 9 may be arranged. Alternatively, the prism film 9 may be disposed on the emission surface, and the diffusion film 8 may be disposed on the prism film 9.

  In the present embodiment, the light source 1 is a point light source, and a side view type pseudo white LED is assumed. However, a top view, a bullet type, or a color other than white may be used. Furthermore, in order to improve the color reproducibility of the display device, an LED light source other than pseudo white may be used. In particular, a liquid crystal panel having a three-wavelength spectral distribution adapted to the spectral transmission characteristics of the color filter of the liquid crystal panel is preferable. Specifically, there is an LED light source including a blue LED element having an emission peak at 420 nm to 480 nm, a green LED element having an emission peak at 500 nm to 560 nm, and a red LED element having an emission peak at 620 nm to 680 nm in one package. Can be mentioned. Further, a near ultraviolet LED having an emission peak at 380 nm to 420 nm is used as excitation light, a blue phosphor having an emission peak at 420 nm to 480 nm, a green phosphor having an emission peak at 500 nm to 560 nm, and a red having an emission peak at 620 nm to 680 nm. An LED light source containing a phosphor is exemplified. In addition to the above two types, a blue LED element having an emission peak at 420 nm to 480 nm is used as excitation light, a green phosphor having an emission peak at 500 nm to 560 nm, and a red phosphor having an emission peak at 620 nm to 680 nm. The LED light source included is mentioned. By using any one of the light sources described above, the color reproducibility of the display device can be improved.

  Furthermore, as a method for suppressing the light emitted from the phosphor from being absorbed by another phosphor, a blue-green LED light source combining a blue LED element and a green phosphor, and a blue LED element and a red phosphor are combined. A method using a purple LED light source can be mentioned. In this method, since the green light emitted from the green phosphor is not absorbed as the excitation light of the red phosphor, the light emission efficiency can be improved as compared with the case where two types of phosphors are mixed.

  The light guide 2a, the light guide 2b, the light guide 2c, and the light guide 2d are molded products of transparent resin such as ZEONOR, PMMA, and PC.

  The present embodiment is different from the first embodiment in the shape of the light guide, but the other configurations are the same. In the first embodiment, the shape of the light incident portion is characterized so that the light from the light source is aligned in a certain direction and is perpendicular to the lower prism. In this embodiment, a regular triangular pyramid-shaped microprism formed on the opposing surface of the light guide is arranged so that the bottom surface of the reflection surface of the microprism is perpendicular to the optical path of light from the light source. With such a configuration, it is possible to irradiate light from the light source perpendicularly to the microprism without aligning the direction of light entering the light guide from the light source, and to emit light vertically from the emission surface.

  The structure of the illumination device of the present embodiment will be described below with reference to FIGS. FIG. 8 is a top view of the illumination device of this embodiment. As shown in FIG. 8, the illumination device of the present embodiment includes a light source 1, and a light guide 2a, a light guide 2b, a light guide 2c, and a light guide 2d arranged adjacent to each other in a planar shape. . These light guides 2a to 2d have basically the same shape and configuration, and guide the light from the light source 1 to the inside from the light incident part 2e to emit light from the emission surface. Although not shown, the light guide 2a and the light guide 2b are arranged so that the end of the light guide 2b overlaps the light incident part of the light guide 2a and the light source facing the light incident part. Yes. Similarly, the light guide 2c and the light guide 2d are arranged so that the end of the light guide 2d overlaps the light incident part of the light guide 2c and the light source facing the light incident part.

  FIG. 9 schematically shows a part of the lighting apparatus of the present embodiment. A light guide 2 that guides light emitted from the light sources 1a and 1b is disposed in front of the light sources 1a and 1b. The light incident portion 2e of the light guide 2 is formed with a light incident surface provided with a semicircular recess corresponding to each light source, and the light source 1a and the light source 1b are arranged so as to correspond to the light incident surface. Is done. The light emitted from the light source 1a and the light source 1b is introduced into the transparent light guide 2 in the region of the light incident portion 2e, and is irradiated to the liquid crystal panel side from the emission surface which is the liquid crystal side surface.

  Innumerable microprisms 13 a and 13 b are formed on the lower surface of the light guide 2. The microprism 13a and the microprism 13b correspond to the light source 1a and the light source 1b, respectively. Further, the microprisms 13a and 13b are arranged alternately. These microprisms 13a and 13b have a regular triangular pyramid shape and are provided with a reflecting surface that reflects light from the light source. In the present embodiment, the surface that reflects light from the light source is used as the reflecting surface of the microprism. When viewed from the front, the microprism 13a and the microprism 13b are arranged such that the direction of the reflecting surface differs depending on the location. The bottom side of the reflecting surface of the microprism 13a is arranged so as to be approximately 90 degrees with respect to the optical path 12a when a straight line connecting the light source 1a and the microprism 13a is defined as the optical path 12a. Further, the bottom of the reflection surface of the microprism 13b is also arranged at approximately 90 degrees with respect to the optical path 12b, where a straight line connecting the light source 1b and the microprism 13b is the optical path 12b.

  By arranging the microprisms in this way, the light from the plurality of light sources hits the reflection surface of the microprism corresponding to each light source and is emitted in the vertical direction from the emission surface of the light guide. Therefore, the lighting device can increase the light use efficiency. In the present embodiment, the number of light sources is two, but even in the case of three or more, if a microprism is arranged corresponding to each light source, the same function as in the present embodiment can be exhibited.

  In the present embodiment, each microprism is a regular triangular pyramid having a height of about 1 to 10 μm and an angle between a straight line connecting the base and the apex and a bottom surface of about 40 to 60 degrees. If the microprism is a triangular pyramid shape, the microprism does not have a plurality of bases that form 90 degrees with the optical path, and has only one reflecting surface, so that an illumination device without uneven brightness can be realized.

  In this embodiment, the shape of the microprism is a regular triangular pyramid, but the bottom of the reflection surface of the microprism forms an angle of approximately 90 degrees with respect to the optical path of one of the light sources. The shape of the microprism is not limited to this as long as the bottom of the side surface does not form an angle of 90 degrees with respect to any of the optical paths of the plurality of light sources.

  For example, as shown in FIG. 10A and FIG. 10B, a side surface other than the reflecting surface of the microprism may be a curved surface. Even if light is irradiated on the side surface depending on conditions such as the LED arrangement position and the light guide size, the curved surface diffuses light, so that the reflection surface of the microprism can be made completely one. In this case, the R of the curved surface of the diffusing surface 14 can be obtained by applying an R of 10 μm to 50 μm when the bottom of the microprism is about 10 μm to 30 μm and the height is about 3 μm to 5 μm. Further, the same effect can be obtained even if the shape is such that R is given in the minus direction to make it indented. Further, the diffusion surface is not limited to a curved surface, and the same effect can be obtained by roughening the surface by providing irregularities.

  FIG. 11 shows a cross-sectional view of the illumination device of this embodiment. Light from the light source 1 enters the light guide 2, strikes the reflecting surface of the microprism 13, and exits vertically from the exit surface. The microprism 13 is formed in a concave shape on the lower surface of the light guide 2. All of the light hitting the microprism 13 is reflected by the reflecting surface and is not emitted from the emitting surface. Some of the light passes through the reflecting surface and is refracted on the other side of the microprism and again. Incident on the light guide 2. In that case, it is preferable that the angle formed by the other side surface and the bottom surface is the same as the angle formed by the reflection surface and the bottom surface. In this embodiment, the angle formed by the reflection surface and the bottom surface is approximately 45 degrees.

  Furthermore, by arranging a plurality of upper prisms on the exit surface of the light guide 2, it is possible to reduce the generation of bright lines. The plurality of upper prisms have apex angles of about 120 to 170 degrees and are formed in parallel with the light traveling direction of the light source. Further, if the exit surface is partially or entirely roughened by a blasting method or the like instead of the upper prism, or if a diffusion layer is formed by a printing method or the like, the effect of reducing the bright line can be obtained as in the case of the upper prism.

  In the present embodiment, a blue-green LED light source and a purple LED light source are used as light sources, and the configuration of the light incident portion 2e of the light guide is different from that of the first embodiment, but other configurations are the same as those of the first embodiment.

  When a blue-green LED light source and a purple LED light source are disposed adjacent to each other as a light source, the parabolic surface 2g at the boundary between the adjacent light incident portions is applied when the configuration of the light incident portion shown in FIG. This prevents color mixing of light from each LED light source.

  Therefore, in this embodiment, the parabolic surface 2g at the boundary between the adjacent light incident portions is eliminated, so that the light incident portion area is unified, and the light from each LED light source is mixed to enter the light guide. It can be so. That is, the light incident part of the present embodiment has a configuration in which two concave portions adjacent to the light incident surface are provided, and the light emitting portions of the blue-green LED and the violet LED are arranged so as to correspond to these concave portions, respectively.

  FIG. 12 is a diagram schematically illustrating a light incident portion of the present embodiment. The light incident portion 2e has a light incident surface in which two adjacent concave portions 2f and 2f 'are formed, and a parabolic surface 2g. The blue-green LED light source 15 and the violet LED light source 16 which are light sources are arranged adjacent to each other, and the blue-green LED light source 15 and the violet LED light source 16 are arranged so that the light output portions face the recesses 2f and 2f ′, respectively. The The light of the blue-green LED light source 15 entering from the light incident part 2f is reflected by the side surface of the recess 2f 'and the parabolic surface 2g on the purple LED light source 16 side, and enters the light guide. Similarly, the light of the purple LED light source 16 entering from the concave portion 2f 'is reflected by the side surface of the concave portion 2f and the paraboloid 2g on the blue-green LED light source 15 side, and enters the light guide. In this way, the light emitted from the blue-green LED light source 15 and the light emitted from the purple LED light source can be uniformly mixed in the area of the light incident portion 2e and can enter the light guide. The arrangement of the LED light sources does not have to be the same as in FIG. 12, and the positions of the blue-green LED light source 15 and the purple LED light source 16 may be switched.

  Further, the light emitted from the blue-green LED light source 15 and the purple LED light source 16 becomes more color-mixing as the pitch between the two recesses of the recess 2f and the recess 2f ′ in FIG. 12 is smaller. However, since the width dimension of a normal side view type LED light source is about 2.4 mm to 4.5 mm, the applicable pitch distance is limited. Therefore, the LED light source to be used should have a width of about 2.4 mm to 3.5 mm and be 4 mm or less. As described above, an illumination device with high color reproducibility can be realized by the configuration based on the present embodiment.

  The lighting device and the display device according to the present invention can be applied to display devices such as a car navigation system and a television. It can also be applied to equipment lighting equipment such as a residence or office.

DESCRIPTION OF SYMBOLS 1 Light source 2a, 2b, 2c, 2d Light guide 2e Light incident part 2f Recessed part 2g Parabolic surface 2h Outgoing surface 2i Reflective surface 3a Straight component 3b Reflective component 4 Reflective sheet 5 Lower prism 6 Light shielding film 7 Frame 8 Upper prism 9 Diffusion Film 10 Prism film 11 Liquid crystal panel 12 Optical path 13 Microprism 14 Diffusion surface 15 Blue-green LED light source 16 Purple LED light source

Claims (12)

A plurality of light guides for emitting light introduced into the inside from the light incident part in a vertical direction from the emission surface;
A plurality of light sources respectively disposed facing the light incident portions of the plurality of light guides,
The plurality of light guides are arranged adjacent to each other with overlapping portions,
In the overlapping portion, the lighting device is arranged such that an end portion of an adjacent light guide overlaps an upper surface of the light incident portion and an upper surface of the light source. The light incident part has a light incident surface provided with a recess so as to face the light emission part of the light source, and a parabolic surface extending in a parabolic shape from the light emission part of the light source in the light emission direction,
The lighting device according to claim 1, wherein a reflective structure is formed on a lower surface of the light guide.   The lighting device according to claim 2, wherein a plurality of prisms are formed on the emission surface in a direction orthogonal to the light incident surface.   The illumination device according to claim 3, wherein the prism is also formed in the light incident portion, and the shape of the prism formed on the light exit surface is different from that of the prism formed on the light incident portion.   The said light source contains the blue-green LED light source which combined the blue LED element and the green fluorescent substance, and the purple LED light source which combined the blue LED element and the red fluorescent substance, The any one of Claims 2-4 characterized by the above-mentioned. The lighting device according to item.   6. The light incident surface is provided with two adjacent concave portions, and the blue-green LED light source and the purple LED light source are disposed to face the concave portions, respectively. Lighting device. A plurality of concave microprisms are formed on the lower surface of the light guide,
The microprism includes a reflective surface that reflects light from the light source and a plurality of other side surfaces.
The bottom surface of the reflecting surface is disposed at an angle of 90 degrees with respect to the light path of any one of the plurality of light sources, and the bottom surface of the side surface is disposed at an angle other than 90 degrees with respect to the light paths of the plurality of light sources. The lighting device according to claim 1.   The illumination device according to claim 7, wherein the microprism has a triangular pyramid shape.   The lighting device according to claim 7, wherein a side surface other than the reflection surface of the microprism is a curved surface. The light incident part has a light incident surface provided with a semicircular recess so as to face the light emission part of the light source, and a parabolic surface extending in a parabolic shape from the light emission part of the light source in the light emission direction.
The lighting device according to any one of claims 7 to 9, wherein the bottom surface of the reflection surface of the microprism is arranged so as to be perpendicular to the light path of the light from the light incident surface.   The lighting device according to claim 1, wherein a light-shielding film is disposed on the light source and the surface of the light incident portion in the overlapping portion. A plurality of light guides for emitting light introduced into the inside from the light incident part in a vertical direction from the emission surface;
A plurality of light sources respectively disposed facing the light incident portions of the plurality of light guides;
A non-self-luminous display element disposed on the exit surface of the light guide,
The plurality of light guides are arranged adjacent to each other with overlapping portions,
The display device, wherein the overlapping portion is arranged so that an end portion of an adjacent light guide overlaps an upper surface of the light incident portion and an upper surface of the light source.

Images