JP2018198120A - Illumination device - Google Patents

Abstract

An object of the present invention is to improve the uniformity of light on the surface of a light guide plate by suppressing shadows in the light guide plate caused by through holes for mounting. A lighting device (10) has a front surface (output surface (32)), a back surface (reflecting surface (33)) opposite to the front surface, and an incident surface (31) on which light is incident. A light guide plate 30 that guides light, reflects the light by a plurality of concave portions 37 formed on the back surface, and emits the light from the front surface, and the extension of the incident surface 31 so that the light is incident on the incident surface 31. and a plurality of light sources 152 arranged along the installation direction. At the end of the light guide plate 30 on the incident surface 31 side, a plurality of through holes 36 penetrating from the front surface to the back surface are arranged along the incident surface. In the facing region H1 facing at least one of the plurality of through holes 36 via the incident surface 31, the plurality of light sources 152 are arranged more densely than in the non-facing regions h1 and h2. [Selection drawing] Fig. 3

Description

  The present invention relates to a lighting device.

  2. Description of the Related Art Conventionally, an illumination device using a light guide plate that makes light from a light source incident on a side surface of the light guide plate and output from the surface of the light guide plate is known (see, for example, Patent Document 1).

JP-A-5-107542

  In the light guide plate, a through hole for attaching to the fixture body of the lighting device is provided, but the through hole blocks light traveling in the light guide plate and causes a shadow in the light guide plate. When a shadow is generated, the appearance of the surface of the light guide plate during light emission is impaired.

  For this reason, an object of the present invention is to provide an illuminating device that can suppress shadows in the light guide plate due to the mounting through-holes and increase the uniformity of light on the surface of the light guide plate. .

  In order to solve the above problems, a lighting device according to one embodiment of the present invention includes a front surface, a back surface opposite to the front surface, and an incident surface on which light is incident, and guides light incident from the incident surface. And a light guide plate that reflects light at a plurality of concave portions formed on the back surface and emits light from the front surface, and is arranged along the extending direction of the incident surface so that the light is incident on the incident surface And a plurality of through holes penetrating from the front surface to the back surface are arranged along the incident surface, and at least of the plurality of through holes. A plurality of light sources are arranged more densely in the facing region facing each other through the incident surface than in the non-facing region.

  According to the present invention, the uniformity of light on the surface of the light guide plate can be enhanced by suppressing the shadow in the light guide plate due to the mounting through-hole.

FIG. 1 is a perspective view of a lighting device according to an embodiment. FIG. 2 is a cross-sectional view of the illumination device according to the embodiment. FIG. 3 is a top view showing the light guide plate and the light emitting module according to the embodiment. FIG. 4 is an explanatory diagram illustrating an example of a shadow formed in the light guide plate by the through hole. FIG. 5 is an explanatory diagram showing an example of a structure that suppresses the generation of shadows due to through holes. FIG. 6 is an explanatory diagram showing a positional relationship between a light source at one end and a through hole at one end according to the embodiment. FIG. 7 is an enlarged view showing a part of the light guide plate according to the first modification. FIG. 8 is an enlarged view showing a part of the light guide plate according to the second modification. FIG. 9 is an enlarged view showing a part of the light guide plate according to the third modification. FIG. 10 is a cross-sectional view of a lighting device according to Modification 4.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each of the embodiments described below shows a preferred specific example of the present invention. Therefore, the numerical values, shapes, materials, components, arrangement positions and connection forms of the components shown in the following embodiments are merely examples, and are not intended to limit the present invention. Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims showing the highest concept of the present invention are described as optional constituent elements.

  Each figure is a schematic diagram and is not necessarily illustrated strictly. Moreover, in each figure, the same code | symbol is attached | subjected to the substantially same structure, The overlapping description is abbreviate | omitted or simplified.

  Hereinafter, a light guide plate and a lighting device using the light guide plate according to embodiments of the present invention will be described.

[Constitution]
First, the structure of the lighting device according to the embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view of a lighting device 10 according to an embodiment. FIG. 2 is a cross-sectional view of the illumination device 10 according to the embodiment.

  As shown in FIGS. 1 and 2, the lighting device 10 is an edge light type lighting device, and is fixed to the ceiling. Specifically, the lighting device 10 is fixed to the ceiling in a state where it is connected to an external power source (not shown) arranged behind the ceiling.

  The lighting device 10 includes a main body 11, a power supply unit 13, a pair of light emitting modules 15, and a pair of light guide plates 30.

  The main body 11 is formed in a long box shape and accommodates a power supply 13 that is electrically connected to an external power supply. Further, light guide plate support portions 21 are provided on both side portions of the main body portion 11, respectively. In addition, since the light-guide plate support part 21 is equivalent in the both sides of the main-body part 11, only one light-guide plate support part 21 is demonstrated and it abbreviate | omits about the other light-guide plate support part 21. FIG.

  The light guide plate support portion 21 is a rectangular groove portion that is recessed from one side surface of the main body portion 11 toward the other side. A plurality of screw holes 211 for screwing the light guide plate 30 are formed on the top surface of the light guide plate support portion 21. The plurality of screw holes 211 are arranged at predetermined intervals along the longitudinal direction of the main body portion 11. The light guide plate 30 supported by the light guide plate support portion 21 is disposed substantially parallel to the ceiling. Further, the inner surface on the back side of the light guide plate support 21 is substantially orthogonal to the top surface of the light guide plate support 21. A light emitting module 15 is attached to the inner side surface of the light guide plate support 21.

  The light emitting module 15 is disposed in the light guide plate support unit 21 and includes a substrate 151 and a plurality of light sources 152.

  The substrate 151 is a long rectangular plate-shaped substrate. The substrate 151 is installed on the inner surface of the light guide plate support portion 21 so as to be parallel to the longitudinal direction of the main body portion 11.

  The plurality of light sources 152 are so-called SMD (Surface Mount Device) type LED elements. Specifically, the SMD type LED element is a package type LED element in which an LED chip (light emitting element) is mounted in a resin-molded cavity, and a phosphor-containing resin is sealed in the cavity. The light source 152 is controlled to turn on and off by a control unit (not shown) provided in the power supply unit 13. Each light source 152 is subjected to dimming / toning control by the control unit.

  The light emitting module 15 is not limited to such a configuration, and a COB (Chip On Board) type light emitting module in which an LED chip is directly mounted on the substrate 151 may be used. The light emitting element included in the light source 152 is not limited to the LED. For example, a semiconductor light emitting element such as a semiconductor laser, or another solid light emitting element such as an EL element such as an organic EL (Electro Luminescence) or an inorganic EL. It may be.

  The plurality of light sources 152 are disposed between the incident surface 31 of the light guide plate 30 and the inner surface of the light guide plate support 21. The light source 152 is arranged so that the emission direction of emitting light faces the incident surface 31 of the light guide plate 30, and makes the light incident toward the incident surface 31. That is, the emission direction of the light source 152 is substantially perpendicular to the incident surface 31 of the light guide plate 30.

  The light guide plate 30 has a rectangular flat plate shape in plan view. The light guide plate 30 is an optical member that guides light from the light source 152 toward an emission surface 32 described later. The light guide plate 30 is formed from a light-transmitting resin such as polycarbonate or acrylic, but may be formed from other light-transmitting materials.

  The light guide plate 30 is supported by the light guide plate support portion 21 so as to be substantially parallel to the ceiling. One side surface disposed in the light guide plate support portion 21 of the light guide plate 30 is an incident surface 31 on which light from the plurality of light sources 152 is incident. The incident surface 31 extends along the longitudinal direction of the main body 11. A plurality of light sources 152 are arranged at predetermined intervals along the extending direction of the incident surface 31.

  Of the pair of main surfaces of the light guide plate 30, one main surface is a surface facing downward, and is an emission surface 32 that emits light. Of the pair of main surfaces of the light guide plate 30, the opposite main surface is the back surface facing the ceiling, and is a reflection surface 33 that reflects light passing through the light guide plate 30. In the light guide plate 30, an incident surface 31 is provided between the emission surface 32 and the reflection surface 33.

  The entrance surface 31 and the exit surface 32 of the light guide plate 30 are flat. The reflection surface 33 of the light guide plate 30 is a surface opposite to the emission surface 32 of the light guide plate 30.

  FIG. 3 is a top view showing the light guide plate 30 and the light emitting module 15 according to the embodiment. As shown in FIG. 3, the light guide plate 30 includes a mixing area M1 and a reflection area M2.

  The reflection region M2 is a region farther from the light source 152 than the mixing region M1, and is a region where the light from the plurality of light sources 152 is mixed and the luminance is made uniform. As shown in FIGS. 2 and 3, a plurality of recesses 37 that are recessed toward the emission surface 32 are arranged in a matrix in the reflection region M <b> 2 of the reflection surface 33 of the light guide plate 30. In other words, it can be said that the reflective region M2 is a region where a plurality of concave portions 37 are formed.

  The concave portion 37 is a prism recessed in a frustum shape or a cone shape. For example, the specific shape of the concave portion 37 includes a truncated cone shape, a truncated pyramid shape, a cone shape, and a truncated pyramid shape. The light traveling through the light guide plate 30 is reflected by the inner surface of the recess 37 in the light guide plate 30, travels toward the exit surface 32, and exits from the exit surface 32 to become illumination light.

  The mixing region M1 is a region where light from the plurality of light sources 152 incident from the incident surface 31 is not sufficiently mixed. The mixing region M1 is interposed between the incident surface 31 and the reflection region M2. A plurality of through holes 36 penetrating from the emission surface 32 to the reflection surface 33 are formed at the end of the mixing region M1 on the incident surface 31 side. The plurality of through holes 36 are arranged at predetermined intervals along the extending direction of the incident surface 31. The light guide plate 30 is supported by the light guide plate support portion 21 by fastening screws 80 to the screw holes 211 of the light guide plate support portion 21 through the plurality of through holes 36.

[Positional relationship between through hole and light source]
By the way, the screwing through hole 36 blocks light traveling in the light guide plate 30. FIG. 4 is an explanatory diagram illustrating an example of a shadow formed in the light guide plate 30 by the through hole 36. FIG. 4 shows a state where one light source 152 is arranged for one through hole 36. As shown in FIG. 4, the light L emitted from the light source 152 enters the light guide plate 30 from the incident surface 31 and travels through the light guide plate 30. At this time, since part of the light L is blocked by the through hole 36, a shadow S <b> 1 is formed in the light guide plate 30. When such a shadow S1 occurs, the appearance of the surface of the light guide plate 30 during light emission is impaired.

  For this reason, in this Embodiment, the structure which suppresses generation | occurrence | production of shadow S1 is employ | adopted. Specifically, the positional relationship between the plurality of through holes 36 and the plurality of light sources 152 is determined so that the generation of the shadow S1 is suppressed. Hereinafter, the positional relationship between the plurality of through holes 36 and the plurality of light sources 152 will be described in detail.

  FIG. 5 is an explanatory diagram showing an example of a structure that suppresses the generation of the shadow S <b> 1 due to the through hole 36. In FIG. 5, a plurality of light sources 152 are arranged more densely than in the case of FIG. 4 in the facing region H <b> 1 that faces the through hole 36 through the incident surface 31 of the light guide plate 30. The facing area H1 is an area on the substrate 151. Specifically, four light sources 152 are arranged at equal intervals in the facing area H1. Thus, when the plurality of light sources 152 are densely arranged in the facing region H1, the shadow S1 is canceled because the through hole 36 is illuminated by the light L emitted from each light source 152. In FIG. 5, only the shadow S1 caused by light from one light source 152 is shown. Actually, a plurality of shadows are formed by the light from all the light sources 152 in the facing region H1, but these shadows are also canceled by the light from the other light sources 152.

  Here, the center of the opposing region H1 is the same position as the center of the through hole 36, and the width of the opposing region H1 is obtained by Expression (1).

  Here, as shown in FIG. 3, α is an angle that is half the irradiation angle of the light source 152. Specifically, α is 42 degrees. The side A is a straight line that intersects the normal line passing through the center of the light source 152 located at the extreme end of the opposed region H1 at an angle α, and is a straight line tangent to the through hole 36. The side B is a normal line of the incident surface 31 and is a straight line passing through the center of the through hole 36. The side C is a straight line connecting the intersection of the incident surface 31 on the side A and the intersection of the incident surface 31 on the side B. The width of the counter area H1 is obtained by doubling the side C. The width of the facing area H1 may be equal to or less than the value obtained by the expression (1).

  Further, the interval between adjacent light sources 152 arranged in the facing region H <b> 1 is smaller than the diameter of the through hole 36. If this distance is greater than or equal to the diameter of the through hole 36, the number of light sources 152 that can be installed in the facing region H1 decreases, and the amount of cancellation of the shadow S1 decreases. In addition, the minimum value of this space | interval is 2 mm. Further, this interval may be the interval between the center positions of the adjacent light sources 152 or may be the gap interval between the adjacent light sources 152.

  In the present embodiment, as shown in FIG. 3, the region facing the through holes 36 other than the through holes 36 at both ends through the incident surface 31 among the plurality of through holes 36 is the facing region H1. On the other hand, the region facing the incident surface 31 in the through holes 36 at both ends is an unmounted region H2 where the light source 152 is not mounted. A region between the plurality of facing regions H1 is a non-facing region h1 that does not face the through hole 36. A region between the facing region H1 and the unmounted region H2 is a non-facing region h2 that does not face the through hole 36. In the present embodiment, since one light source 152 is arranged at the boundary between the unmounted region H2 and the non-facing region h2, the light source 152 partially enters the unmounted region H2. Even in this case, it is assumed that the light source 152 is not mounted in the unmounted region H2.

  Here, also in the non-facing regions h1 and h2, if a plurality of light sources 152 are arranged at the same density as the facing region H1, the number of light sources 152 to be installed increases, resulting in an increase in cost. For this reason, in the non-facing regions h1 and h2, it is required to arrange a plurality of light sources 152 with a density lower than that of the facing region H1. At this time, if a plurality of light sources 152 are evenly arranged in the non-opposing regions h1 and h2, the luminance changes sharply at the boundary portion with the opposing region H1 in which the light sources 152 are densely arranged, resulting in luminance unevenness. It will stand out. In order to suppress this luminance unevenness, the arrangement of the plurality of light sources 152 in the non-facing regions h1 and h2 is appropriate.

  For example, the plurality of light sources 152 arranged in the non-facing region h1 are arranged so that the interval increases as the distance from the facing region H1 increases. Since the non-opposing region h1 is a region sandwiched between the two opposing regions H1, the interval between the plurality of light sources 152 is the largest in the middle and the interval between both ends is the smallest. As shown in FIG. 3, when the six light sources 152 are arranged in the non-facing region h1, the relationship between the middle distance d3, the distance d1 between both ends, and the distance d2 between them is d1 <d2 <d3. The interval d1 is larger than the interval between the plurality of light sources 152 in the facing region H1.

  In addition, the plurality of light sources 152 arranged in the non-opposing area h2 are arranged so that the interval increases as the distance from the opposing area H1 increases. As shown in FIG. 3, when five light sources 152 are arranged in the non-facing area h2, assuming that the distance d4, the distance d5, the distance d6, and the distance d7 are in order of increasing distance from the facing area H1, these relationships are , D4 <d5 <d6 <d7. The interval d4 is larger than the interval between the plurality of light sources 152 in the facing region H1.

  In this way, in the non-opposing areas h1 and h2, the plurality of light sources 152 are arranged so that the intervals increase as they move away from the facing area H1, and therefore the luminance gradually decreases as they move away from the facing area H1. Become. That is, it is possible to suppress a sharp change in luminance at the boundary between the facing region H1 and the non-facing regions h1 and h2, and to suppress the unevenness in luminance.

  Next, the positional relationship between the light sources 152 at both ends and the through holes 36 at both ends will be described.

  FIG. 6 is an explanatory diagram showing a positional relationship between the light source 152 at one end and the through hole 36 at one end according to the embodiment. In addition, since the positional relationship between the light source 152 and the through hole 36 is the same as that on the one end side on the other end side, the description thereof is omitted here.

  As shown in FIG. 6, among the plurality of light sources 152, the light source 152 at one end in the extending direction is a shadow S <b> 2 formed when light is irradiated to the through hole 36 at one end among the plurality of through holes 36. Is arranged at a position within the mixing region M1 of the light guide plate 30. Accordingly, it is possible to prevent the shadow S2 caused by the through hole 36 at one end from entering the reflection region M2 without providing the light source 152 densely in the unmounted region H2.

[Effects, etc.]
As described above, the illumination device 10 according to the present embodiment has the front surface (the exit surface 32), the back surface opposite to the front surface (the reflective surface 33), and the incident surface 31 on which light is incident. The light incident from the surface 31 is guided, the light is reflected by the plurality of concave portions 37 formed on the back surface, and the light is incident on the incident surface 31 and the light guide plate 30 that emits light from the front surface. And a plurality of light sources 152 arranged along the extending direction of the incident surface 31. At the end of the light guide plate 30 on the incident surface 31 side, a plurality of through holes 36 penetrating from the front surface to the back surface are arranged along the incident surface. In the facing region H1 that faces at least one of the plurality of through holes 36 via the incident surface 31, the light sources 152 are arranged more densely than the non-facing regions h1 and h2.

  According to this, since the plurality of light sources 152 are arranged more densely in the facing region H1 than in the non-facing regions h1 and h2, the through hole 36 is illuminated by the plurality of light sources 152. As a result, the shadow S <b> 1 formed when irradiated by one light source 152 is canceled by the light from the other light sources 152. Therefore, it is possible to suppress the shadow S1 in the light guide plate 30 due to the mounting through-hole 36, and it is possible to improve the uniformity of light on the emission surface 32 of the light guide plate 30.

  In addition, the plurality of light sources 152 arranged in the facing area H1 are arranged at equal intervals, and the plurality of light sources 152 arranged in the non-facing areas h1 and h2 are arranged such that the distance increases as the distance from the facing area H1 increases. It is arranged.

  According to this, in the non-facing regions h1 and h2, the plurality of light sources 152 are arranged so that the intervals increase as they move away from the facing region H1, and thus the luminance gradually decreases as they move away from the facing region H1. become. That is, it is possible to suppress a sharp change in luminance at the boundary between the facing region H1 and the non-facing regions h1 and h2, and to suppress the unevenness in luminance.

  In addition, among the plurality of light sources 152, the light sources 152 at both ends in the extending direction have shadows S <b> 2 formed when light is irradiated on the through holes 36 at both ends of the plurality of through holes 36. It is arranged at a position within the mixing area M1.

  According to this, since the shadow S2 caused by the through holes 36 at both ends is within the mixing region M1 of the light guide plate 30, the shadow S2 is added to the reflection region M2 without providing the light source 152 densely in the unmounted region H2. It is possible to prevent entry. Accordingly, it is possible to improve the uniformity of light on the exit surface 32 of the reflection region M2.

  In the plurality of through holes 36, the plurality of light sources 152 are arranged more densely than the non-opposing areas h 1 and h 2 in the plurality of facing areas H 1 that face the through holes 36 other than the through holes 36 at both ends.

  According to this, since the plurality of light sources 152 are arranged more densely than the non-facing regions h1 and h2 in all of the plurality of facing regions H1, shadows caused by the through holes 36 other than the through holes 36 at both ends are caused. Can be suppressed. Therefore, the uniformity of light on the surface of the light guide plate 30 can be further improved.

[Modification 1]
In the above embodiment, the case where the plurality of recesses 37 are arranged in a matrix on the reflection surface 33 of the light guide plate 30 is illustrated. In Modifications 1 to 3, other layout examples of the plurality of recesses 37 will be described. In the following description, the description of the same part as the above embodiment may be omitted.

  FIG. 7 is an enlarged view showing a part of the light guide plate 30A according to the first modification. In FIG. 7, among the light emitted from each of the plurality of light sources 152, the light reaching the through hole 36 and the shadow formed when the light is blocked by the through hole 36 are indicated by a pair of virtual lines L <b> 2 and L <b> 3. ing. That is, in the portion sandwiched between the pair of virtual lines L2 and L3, the light from the through hole 36 to the light source 152 shows light, and the opposite side portion shows a shadow.

  As shown in FIG. 7, in the light guide plate 30 </ b> A, the coverage of the plurality of recesses 37 per unit area on the reflection surface 33 a is a region that overlaps the shadow of the through hole 36 formed by the light from each of the plurality of light sources 152. It is higher than other areas. Here, the region superimposed on the shadow of the through hole 36 is a region showing a shadow sandwiched between the pair of virtual lines L2 and L3. Thus, in the reflective region M2 of the reflective surface 33a, the coverage of the region sandwiched between the pair of virtual lines L2 and L3 is higher than the other regions. In the first modification, the coverage of the region superimposed on the shadow is constant, and the coverage of other regions is also constant.

  Here, the coverage is the ratio of the portion occupied by the plurality of recesses 37 per unit area. When the plurality of recesses 37 have the same shape, the coverage can be said to be the density of the recesses 37. In addition, the coverage can be adjusted by changing the size of the recess 37. In a portion where the coverage is high, a large amount of light is reflected toward the emission surface 32 by the plurality of concave portions 37, so that the luminance is increased. That is, even if a shadow is generated, the luminance in the area is increased, and the difference in luminance from other areas is reduced. Therefore, the uniformity of the light at the exit surface 32 of the light guide plate 30 can be further improved.

[Modification 2]
FIG. 8 is an enlarged view showing a part of the light guide plate 30B according to the second modification. FIG. 8 corresponds to FIG. In the modification 1, the case where the coverage of the area | region superimposed on a shadow is constant was illustrated. In the second modification, the case where the coverage of the region superimposed on the shadow is changed depending on the location will be exemplified.

  Here, the shadow caused by the through hole 36 becomes thinner as the distance from the incident surface 31 increases. That is, in the portion far from the incident surface 31, the difference in luminance from other regions is small. For this reason, in the area | region which overlaps with the shadow of the through-hole 36 in the reflective surface 33b of the light-guide plate 30B, a coverage rate is made low so that it leaves | separates from the entrance plane 31, and the brightness nonuniformity in the extending direction of a shadow is suppressed. In this case, the lower limit value of the coverage may be set to a value that reflects the light in the light guide plate 30B without uneven brightness. That is, it is better not to reduce the coverage to zero.

  In addition, at both ends of the region superimposed on the shadow, the shadow is faded by light from the other region, and the difference in luminance from the other region is small. For this reason, the luminance unevenness in the width direction of the shadow is suppressed by increasing the coverage at the central portion of the region superimposed on the shadow and lowering the coverage at the both end portions as compared with the central portion. Further, the coverage does not change steeply at the boundary portion between the region superimposed on the shadow and the other region (the vicinity of the pair of virtual lines L2 and L3). Thereby, the uncomfortable feeling by the difference in the coverage of the area | region superimposed on a shadow and another area | region can be suppressed.

  In the second modification, the case where both the luminance unevenness countermeasure in the shadow extending direction and the luminance unevenness countermeasure in the shadow width direction are both exemplified is illustrated, but even if only one countermeasure is taken. Good.

[Modification 3]
FIG. 9 is an enlarged view showing a part of the light guide plate 30 </ b> C according to the third modification. FIG. 9 corresponds to FIG. In the first modification, the case where the coverage is different between the inside and outside of the region superimposed on the shadow is exemplified. In the third modification, a case where the coverage is changed depending on the location regardless of the region superimposed on the shadow is illustrated.

  As shown in FIG. 9, in the reflection surface 33 c of the light guide plate 30 </ b> C according to the third modification, the plurality of concave portions 37 are arranged so as to form a horizontal stripe pattern in a portion close to the incident surface 31. Specifically, the plurality of concave portions 37 in each row in the portion close to the incident surface 31 are wider than the other portions. As described above, the shadow caused by the through hole 36 becomes thinner as the distance from the incident surface 31 increases. For this reason, if the pattern which can be visually recognized only in the part close | similar to the entrance plane 31 is formed in the some recessed part 37, the said pattern can be conspicuous and the illusion that a shadow does not exist can be given to a user.

  Note that the plurality of recesses 37 may form a pattern other than that exemplified in Modification 3 as long as an illusion can be made that there is no shadow in the pattern formed by the plurality of recesses 37.

[Modification 4]
In the said embodiment, the case where the light-guide plate 30 was flat form was illustrated. In the fourth modification, the case where the end portion on the incident surface side of the light guide plate 30D is bent will be described as an example.

  FIG. 10 is a cross-sectional view of a lighting device 10D according to Modification 4. As shown in FIG. 10, the light guide plate 30 </ b> D provided in the lighting device 10 </ b> D has an end on the incident surface 31 side bent, and the incident surface 31 faces downward. The light emitting module 15 is installed on the bottom surface of the light guide plate support portion 21 so that the plurality of light sources 152 face the incident surface 31 of the light guide plate 30D.

  In the facing region H1 in the above embodiment, the case where the plurality of light sources 152 and the through holes 36 are linearly opposed is illustrated, but in the facing region according to the fourth modification, the plurality of light sources 152 and the through holes 36 are penetrated. The hole 36 is opposed in a curved manner. In any case, in the facing region, the plurality of light sources 152 and the through holes 36 face each other in the traveling direction of the light incident from the incident surface 31 into the light guide plates 30 and 30D. Also in the illuminating device 10D which concerns on this modification 4, there can exist an effect similar to the illuminating device 10 which concerns on the said embodiment.

[Others]
As mentioned above, although the illuminating device 10 and the light-guide plate 30 which concern on this invention were demonstrated based on the said embodiment and the modifications 1-4, this invention is limited to said embodiment and the modifications 1-4. It is not something.

  For example, in the above-described embodiment, the case where the light source 152 is not mounted as the unmounted region H2 in the region facing the through holes 36 at both ends among the plurality of through holes 36 is illustrated. However, even in the region facing the through holes 36 at both ends, it may be a facing region where the light source 152 is arranged more densely than the non-facing regions h1 and h2. Thereby, it is possible to suppress the occurrence of shadows due to the through holes 36 at both ends.

  Moreover, in the said embodiment, although the case where the some light source 152 was arrange | positioned densely rather than the non-opposing area | region h1, h2 in all the three opposing area | regions H1 was illustrated, in at least 1 opposing area | region H1, It is only necessary that the plurality of light sources 152 be arranged more densely than the non-facing regions h1 and h2.

  Moreover, in the said embodiment, the case where the some light source 152 arrange | positioned in the non-facing area | region h1 and h2 was arranged so that an interval became large as it left | separated from the opposing area | region H1 was illustrated. However, the non-opposing regions h1 and h2 may have any layout of the light sources 152 as long as the density is lower than that of the opposing region H1. For example, in the non-facing regions h1 and h2, a plurality of light sources 152 may be arranged at equal intervals.

  In addition, the embodiment can be realized by arbitrarily combining the components and functions in each embodiment without departing from the scope of the present invention, or a form obtained by subjecting each embodiment to various modifications conceived by those skilled in the art. Forms are also included in the present invention.

10, 10D Illumination device 30, 30A, 30B, 30C, 30D Light guide plate 31 Entrance surface 32 Exit surface (surface)
33, 33a, 33b, 33c Reflective surface (back surface)
36 Through-hole 37 Recessed portion 152 Light source h1, h2 Non-opposing region H1 Opposing region L Light M1 Mixing region S1, S2 Shadow

Claims (6)

It has a front surface, a back surface opposite to the front surface, and an incident surface on which light is incident, guides light incident from the incident surface, and reflects the light at a plurality of recesses formed on the rear surface. A light guide plate for emitting light from the surface;
A plurality of light sources arranged along the extending direction of the incident surface so that light is incident on the incident surface;
A plurality of through holes penetrating from the front surface to the back surface are arranged along the incident surface at an end portion on the incident surface side of the light guide plate,
The illuminating device, wherein the plurality of light sources are arranged more densely in a facing region facing at least one of the plurality of through holes via the incident surface than in a non-facing region. A plurality of light sources arranged in the facing region are arranged at equal intervals,
The illuminating device according to claim 1, wherein the plurality of light sources arranged in the non-opposing region are arranged so that the interval increases as the distance from the opposing region increases. Among the plurality of light sources, light sources at both ends in the extending direction have shadows formed when light is irradiated to the through holes at both ends of the plurality of through holes in the mixing region of the light guide plate. The lighting device according to claim 1, wherein the lighting device is disposed at a position to be accommodated. The said several light source is arrange | positioned more densely than the said non-opposing area | region in the said some opposing area | region which opposes through-holes other than the through-hole of the said both ends among these several through-holes. Lighting device. 5. The coverage of the plurality of recesses on the back surface is higher in the region overlapping with the shadow of the through hole formed by light from each of the plurality of light sources than in other regions. The lighting device according to one item. The illuminating device according to any one of claims 1 to 5, wherein a coverage of the plurality of concave portions on the back surface decreases as the distance from the incident surface side increases.

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