JP5887556B2 - Lighting device - Google Patents

Description

  The present invention relates to an illumination device that emits light from a light source through a light guide material.

  Conventionally, as an illuminating device, as shown in Patent Documents 1 and 2, a so-called edge in which light from a light source enters a light guide plate from one end and is irradiated from the other surface (light exit surface) of the light guide plate. There is a light-type lighting device. And in the said illuminating device, the light-incidence side of a light source and a light-guide plate is collectively covered with a reflecting plate, the light of a light source is reflected with a reflecting plate, and it is easy to irradiate a light-incident surface, and the light emission of a light-guide plate The amount of light emitted from the surface to the outside is increased.

JP 2001-312213 A Japanese Patent Laid-Open No. 2004-95390

  By the way, in this type of lighting device, a change or a difference in the longitudinal dimension of the light guide plate is likely to occur due to thermal expansion and contraction or dimensional variation during manufacturing, and if this change occurs, the space surrounded by the reflector plate The position of the light incident surface of the light guide plate in the interior varies. When the position of the light incident surface fluctuates, in the conventional illumination devices such as Patent Documents 1 and 2, the light incident surface of the light guide plate is covered with the reflective plate, so that the light reflected by the reflective plate is incident on the light incident surface. Incident conditions may change from the design time, making it difficult to enter the light incident surface. Further, since the light source is also covered with the reflection plate in the conventional illumination device, the light that is difficult to enter the light incident surface is easily reflected by the reflection plate, etc. The light that reaches the light source is absorbed by the light source. As described above, the conventional lighting device has a problem that when the longitudinal dimension of the light guide plate is changed, the light incident efficiency to the light guide plate is reduced, and the light amount from the light exit surface is reduced.

  Therefore, the present invention has been invented in view of the above-described conventional problems, and the object of the present invention is to enter the light beam when the focal point is located between the light collecting portion and the light incident surface of the light guide material. An object of the present invention is to provide an illuminating device that can easily reduce a decrease in light efficiency.

In order to solve the above-described problems, the present invention includes a light source, a light collecting unit that collects light from the light source, and a light guide material on which the light collected by the light collecting unit is incident from a light incident surface. In addition, a reflecting member having a bottomed cylindrical shape and reflecting the entire inner surface of the peripheral wall of the tube as a reflecting surface is provided on the light incident surface side of the light guide material, and the reflecting member is condensed by the light collecting portion. The bottom portion has a point light transmitting portion that transmits light at the focal point of the light collecting portion, and the reflecting member has the bottom portion opposed to the light incident surface of the light guide material, and the light is guided by the peripheral wall. covering the light incident surface side of the timber, characterized in that it the distance between the bottom portion of the reflecting member and the light guide member and the reflecting member against the light guide member as slidably and variable.

  As the illumination device, the light guide material is formed in a long rod shape, and both end faces in the longitudinal direction of the light guide material are the light incident surfaces, and the light source, the light condensing unit, and the light incident surface for each light incident surface. Preferably, a reflecting member is provided, and the reflecting member has an inner surface of the bottom portion as a reflecting surface in addition to the peripheral wall.

  As this illuminating device, it is preferable that the bottom part has a shape that is closer to the light incident surface as a part away from the point light transmitting part.

  As this illuminating device, a plurality of the light sources are provided side by side along the light incident surface, the light condensing portions are provided between the light incident surfaces of the light sources, and the bottom portions are provided at positions corresponding to the light condensing portions. It is preferable that each of the point light transmitting portions is provided.

The present invention includes the above-described configuration, so that the reflective member can be slid relative to the light guide material even if there is a change or difference in the longitudinal dimension of the light guide plate due to dimensional variation during thermal expansion or contraction or manufacturing. The position of the point light transmitting portion at the bottom of the reflecting member can be positioned at the focal point of the light collecting portion, and at the same time, the substantially entire inner surface covers the light incident surface side of the light guide material with a peripheral wall that is a reflecting surface. For this reason, the light passing through the light transmission part can be reflected on the inner surface of the peripheral wall of the reflecting member and easily irradiated on the light incident surface, and the collected light can be easily incident on the light incident surface. it can. Thereby, the present invention can easily improve the irradiation efficiency from the light exit surface.

It is a perspective view of the reflective member periphery of the illuminating device of a 1st example. (A) is a typical top view same as the above, (b) is CC sectional drawing of Fig.2 (a). It is a figure which shows an optical analysis result same as the above, (a) is a case where the space | interval of a condensing part and a light-incidence surface is narrow, (b) is a case where the said space | interval is wide. It is a figure of the state which removed the reflection member from FIG. 3, (a) is a case where the space | interval of a condensing part and a light-incidence surface is narrow, (b) is a case where the said space | interval is wide. It is a typical top view at the time of reflecting the light radiate | emitted from the light-incidence surface of the 1st example by the bottom part. It is a typical top view of the illuminating device of the 2nd example. (A) is explanatory drawing of the opposing light same as the above, (b) is a figure which shows the optical-analysis result of opposing light. FIG. 7 shows a state in which the reflecting member is removed from FIG. 7, (a) is an explanatory diagram of the counter light, and (b) is a diagram showing an optical analysis result of the counter light. It is a figure which shows the optical-analysis result of the illuminating device of a 3rd example, (a) is a case where it is a pyramid shape, (b) is a case where it is a hemisphere shape. FIG. 10 is a schematic plan view when light emitted from the light incident surface in the case of FIG. 9A is reflected at the bottom. It is a perspective view of the reflective member periphery of the illuminating device of the 4th example.

  Embodiments of the present invention will be described below.

  As illustrated in FIG. 1, an illuminating device 1 exemplified in the first embodiment includes a light source 2, a condensing unit 3 that condenses and emits light from the light source 2, and a transparent device. The light guide material 4 which has optical property, and the reflection member 10 (details are mentioned later) are provided. The light source 2 is a so-called point light source having a light emitter such as an LED (light emitting diode). The condensing unit 3 is formed by, for example, a light incident lens (condensing lens). As shown in FIG. 2, the condensing part 3 condenses the light emitted from the light source 2 in a predetermined direction (see the condensing direction D1 in the figure) by refraction or reflection. The condensed light has a focal point S1 at a predetermined distance from the light collecting unit 3 in the light collecting direction D1.

  The light guide 4 has a rectangular bar shape (square bar shape) that is long in the light collecting direction D1. The light guide material 4 has a planar shape in which both end faces (end faces of the bars) in the longitudinal direction along the light collecting direction D1 are substantially orthogonal to the light collecting direction D1. The light guide member 4 has one end face facing the light source 2 and the light collecting section 3 in the light collecting direction D1, and the light condensed by the light collecting section 3 enters the end face. In other words, in the light guide material 4, one end surface in the longitudinal direction is a light incident surface 4a for entering light from the light source 2 into the light guide material 4, and the light source is located at a position facing the light incident surface 4a. 2 and the condensing part 3 are provided.

  Furthermore, the light guide material 4 has a substantially uniform cross section in the light collecting direction D1 (longitudinal direction). Of the four peripheral surfaces 5 (surfaces other than the end surfaces) that are long in the longitudinal direction, one of the peripheral surfaces 5 (first surface 5a) emits light from the light incident surface 4a (externally). The light exit surface 4b is irradiated. As described above, the light guide 4 has a direction in which the direction of the light exit surface 4b is substantially orthogonal to the direction of the light entrance surface 4a. And the light emission surface 4b radiate | emits light in the direction (refer the irradiation direction D2 in FIG. 1) substantially orthogonal to the condensing direction D1.

Moreover, the light guide 4 has the light-diffusion part 6 in the surrounding surface 5 (2nd surface 5b) which turns away from the 1st surface 5a in the irradiation direction D2. For example, the light diffusing unit 6 is formed by coating the second surface 5b by printing, plating, uneven processing, or a member having a light transmittance different from that of the light guide material 4 by coating such as two-color molding. These are provided on the two surfaces 5b. The light diffusing unit 6 reflects or diffuses the light in the light guide material 4 to suppress emission (light leakage) from the second surface 5b, or the light in the light guide material 4 to the first. surface 5a or easily reach the (light emitting surface 4b) side. Hereinafter, of the four peripheral surfaces 5 of the light guide material 4, the remaining two peripheral surfaces 5 other than the first surface 5a and the second surface 5b are side surfaces 5c as shown in FIG. It is difficult to leak light by reflecting or diffusing light.

  Thus, the lighting device 1 arranges the light source 2 so as to face the longitudinal direction of the light guide material 4 and emits the light of the light source 2 from the peripheral surface 5 intersecting the longitudinal direction of the light guide material 4. It is an edge light type lighting device. In addition, it is preferable that the illuminating device 1 further provides the light-diffusion part 6 in the end surface on the opposite side to the light-incidence surface 4a of the light guide material 4, and suppresses the light leakage from the said opposite end surface.

  By the way, as shown in FIG. 4A, when the light incident surface 4a is positioned less than a predetermined distance from the focal point S1 in the light condensing direction D1, the light guide material 4 can easily obtain high light incident efficiency. However, as shown in FIG. 4B, the light incident surface 4a may be positioned away from the focal point S1 by more than the predetermined distance due to thermal expansion and contraction, dimensional variation during manufacturing, or the like. is there. In this case, some of the light that has passed through the focal point S1 is outside of the light incident surface 4a before reaching the light incident surface 4a (based on an imaginary straight line along the condensing direction D1 and passing through the focal point S1). The outer surface of the light incident surface 4a in the radially outward direction. And since this one part light which spread | diffused outward becomes difficult to be irradiated to the light-incidence surface 4a (it becomes difficult to enter light), the illuminating device 1 is light incident compared with the case where it is less than the said predetermined distance. Efficiency is reduced. On the other hand, in this example, as shown in FIG. 3, by providing the reflecting member 10, the outwardly spread light can easily enter the light incident surface 4a.

  Specifically, as shown in FIGS. 1 to 3, the reflecting member 10 has a bottomed cylindrical shape with a rectangular cross section. And the reflecting member 10 has the bottom part 11 of the cylinder and the opening end of the cylinder aligned in the condensing direction D1, and the bottom part 11 side is located closer to the condensing part 3 side than the opening end side in the condensing direction D1. . The inside of the opening end is substantially the same shape and size as the light guide 4 when viewed in the light collecting direction D1. In other words, the reflecting member 10 has a rectangular box shape in which one end in the light collecting direction D <b> 1 is opened with approximately the same shape and the same size as the light guide material 4.

  The bottom part 11 is located between the light source 2 (light collecting part 3) and the light incident surface 4a of the light guide member 4 in the light collecting direction D1. And the bottom part 11 is a rectangular plate shape, and the inner surface 11a (plate surface inside the cylinder) faces the light incident surface 4a. Therefore, the illuminating device 1 is arranged in order of the light source 2, the condensing part 3, the bottom part 11 of the reflection member 10, and the light-incidence surface 4a (light guide material 4) in the condensing direction D1.

  Further, the bottom portion 11 is provided with a point light transmitting portion 13 at a position on an imaginary straight line along the light collection direction D1 and passing through the focal point S1. The point translucent part 13 can transmit the light condensed by the condensing part 3 (light of the light source 2), and the reflecting member 10 positions the point translucent part 13 at the focal point S1, The light gathering at the focal point S1 can be introduced into the cylinder. The point transmissive part 13 is smaller than the bottom part 11, the condensing part 3, and the light incident surface 4 a of the light guide material 4, for example, penetrating through the bottom part 11 along the condensing direction D <b> 1. It is a hole 13a. The through-hole 13a is provided substantially at the center of the bottom portion 11, and is rectangular when viewed in the light condensing direction D1 and smaller than the light condensing portion 3 and the light incident surface 4a of the light guide member 4 or the like. It has become.

  Further, in the reflecting member 10, substantially the entire inner surface 12 a (inner peripheral surface) of the cylindrical peripheral wall 12 is a reflective surface capable of reflecting light. Accordingly, the reflecting member 10 can easily irradiate the light incident surface 4a of the light guide member 4 with light introduced into the reflecting member 10 directly or by reflection on the inner surface 12a of the peripheral wall 12.

  In the reflecting member 10, the peripheral wall 12 is attached to the light incident surface 4 a side of the light guide material 4, and the peripheral wall 12 covers the site on the light incident surface 4 a side. In other words, the reflecting member 10 has the light incident surface 4a side of the light guide material 4 arranged inside the cylinder, and the peripheral wall 12 defines the light incident portion side of the light guide material 4 as the four peripheral surfaces 5 (four rounds). Covering.

  Further, the reflecting member 10 is slidable in the light collecting direction D1 with respect to the light guide material 4. Accordingly, the reflecting member 10 can change the position of the bottom portion 11 between the light source 2 and the light guide material 4. In other words, the reflecting member 10 is attached to the light guide member 4 with the position of the bottom 11 being variable in the light collecting direction D1.

  Thus, the illuminating device 1 arrange | positions the point light transmission part 13 in the focus S1 located between the condensing part 3 and the light guide material 4 in the condensing direction D1. Accordingly, the lighting device 1 can easily irradiate the light incident surface 4a by reflecting the light that is difficult to irradiate the light incident surface 4a on the inner surface 12a of the peripheral wall 12. Therefore, the illuminating device 1 can make it easy to enter the condensed light into the light-incident surface 4a, and can improve the light-incidence efficiency to the light guide material 4. FIG. In other words, the illuminating device 1 can easily reduce a decrease in light incident efficiency when the focal point S <b> 1 is located between the light collecting unit 3 and the light incident surface 4 a of the light guide member 4. Therefore, the illuminating device 1 can easily reduce the amount of light from the light exit surface 4b due to the generation of light that is difficult to be irradiated, and can easily improve the irradiation efficiency from the light exit surface 4b. it can.

  And since the reflection member 10 is located in the light-guide material 4 side from the light source 2 or the condensing part 3, the illuminating device 1 can make the light reflected by the reflection member 10 difficult to reach the light source 2, and the said reflection It is possible to prevent the generated light from reaching the light source 2 and being absorbed. Thereby, the illuminating device 1 can make it easy to suppress the light quantity fall from the light emission surface 4b by the light absorption by the light source 2, and can make it easy to improve the irradiation efficiency from the light emission surface 4b.

  Furthermore, the illuminating device 1 can adjust the position of the bottom part 11 (point translucent part 13) in the condensing direction D1 by sliding the reflecting member 10 with respect to the light guide material 4. Thereby, the illuminating device 1 can make it easy to position the point light transmission part 13 in the focus S1, and can make it easy to introduce the light condensed by the light source 2 into the reflecting member 10.

  The lighting device 1 may be slidable with respect to the reflecting member 10 in addition to the sliding movement. In this case, when the light guide member 4 is thermally expanded or contracted, the illuminating device 1 sets the position of the light incident surface 4a in the condensing direction D1 in the state where the point light transmitting portion 13 is located at the focal point S1. Can be changed. In other words, in the lighting device 1, the position of the light incident surface 4 a changes with respect to the reflecting member 10 in a state where the point light transmitting portion 13 is located at the focal point S <b> 1 during the thermal expansion / contraction or the like. In this case, since the illuminating device 1 suppresses the light leakage outward from the light incident surface 4a by the reflecting member 10, the light incident efficiency to the light guide material can be made substantially the same as before the change of the position. . Thereby, the illuminating device 1 can make it easy to improve the irradiation efficiency from the light emission surface 4b.

  Further, in this type of lighting device 1, light that does not enter the light incident surface 4 a due to reflection or diffusion on the light incident surface 4 a, reflection or diffusion on the side surface 5 c of the light guide material 4 or the light diffusion portion 6, or the like. May cause light L1 and the like emitted from the light incident surface 4a. In this example, as shown in FIG. 5, the reflecting member 10 also forms the reflecting surface on the inner surface 11 a of the bottom portion 11, and the inner surface 11 a of the bottom portion 11 can reflect the light in the reflecting member 10. Yes. Therefore, the illuminating device 1 irradiates the light incident surface 4a with the light that does not enter or the light L1 emitted from the light incident surface 4a, for example, by being reflected by the inner surface 11a of the bottom 11, and the light incident surface 4a (guide light). The light material 4) can be easily incident. Thereby, the illuminating device 1 can easily reduce the decrease in the amount of light due to reflection on the light incident surface 4a, light emitted from the light incident surface 4a, and the like, and improves the irradiation efficiency from the light output surface 4b. Can be made easier.

  Next, a second example is shown as a modification. In addition, the same code | symbol is attached | subjected to the structure which overlaps with the above-mentioned example (1st example), the overlapping description is abbreviate | omitted, and the characteristic etc. of this example (2nd example) are demonstrated hereafter.

  As shown in FIGS. 6 to 8, the lighting device 1 may be arranged with the light sources 2 facing each other at both ends in the longitudinal direction of the light guide material 4. In this case, the illuminating device 1 has the condensing part 3 provided between each edge part of the light guide material 4 in the longitudinal direction and each light source 2 facing it. Therefore, both ends of the light guide material 4 are the light incident surfaces 4a of the light sources 2 facing each other, and the light of the light source 2 collected by the light collecting unit 3 enters from both the longitudinal directions. As a result, the illumination device 1 has a light spot (from the light exit surface 4b) compared to the case where the light source 2 or the like is disposed only in one of the longitudinal directions and only one of the light guide members 4 is used as the light entrance surface 4a. Light spots) can be easily reduced.

  By the way, in the state where the reflection member 10 is not provided, as shown in FIG. 8, a part of the light incident on the light guide material 4 from each light source 2 is incident on the light incident surface 4a (incident on the opposite side of the light source 2). The light incident surface 4a) opposite to the light incident surface 4a may be emitted. Hereinafter, this light is referred to as counter light L2.

  In this example, as shown in FIG. 7, the reflecting members 10 are provided between the light collecting direction D <b> 1 between the light source 2 and the light collecting unit 3 and the light incident surface 4 a of the light guide material 4. In the reflecting member 10, the inner surface 11a of the bottom 11 and the inner surface 12a of the peripheral wall 12 are reflecting surfaces capable of reflecting light. Each of the reflecting members 10 is slidable in the light collecting direction D1 with respect to the light guide material 4.

  Thus, in this example, when the focal point S1 is positioned between the light condensing unit 3 and the light guide member 4, the reflecting member 10 is disposed with the point light transmitting unit 13 positioned at the focal point S1. Thereby, the illuminating device 1 can make it easy to irradiate the said light-incident surface 4a by reflecting the light which is hard to be irradiated to the said light-incidence surface 4a with the inner surface 12a of the surrounding wall 12, etc. FIG. Therefore, the illuminating device 1 can easily reduce the decrease in the light incident efficiency when the focal point S1 is positioned between the light collecting unit 3 and the light incident surface 4a, and the irradiation efficiency from the light emitting surface 4b can be reduced. It can be easily improved.

  The lighting device 1 uses the inner surface 11a of the bottom portion 11 as a reflecting surface, so that the opposing light L2, the light L1 (not shown), and the like are reflected by the inner surface 11a of the bottom portion 11 and the inner surface 12a of the peripheral wall 12 to be guided. Light can be easily incident on the light material 4. Thereby, the illuminating device 1 can make it easy to reduce the decrease in the amount of light due to the counter light L2 and the like, and can easily improve the irradiation efficiency from the light exit surface 4b.

  Furthermore, the illuminating device 1 can adjust the position of the bottom part 11 (point translucent part 13) in the condensing direction D1 by slidingly moving the reflecting member 10 with respect to the light guide member 4. Thereby, the illuminating device 1 can make it easy to position the point light transmission part 13 in the focus S1, and can make it easy to introduce the light condensed by the light source 2 into the reflecting member 10.

  Next, a third example is shown as another modification. Note that the same components as those in the first and second examples described above are denoted by the same reference numerals, and redundant description is omitted. Hereinafter, features of this example (third example) will be described.

  In this example, the bottom part 11 of the reflecting member 10 is shaped so as to be closer to the light incident surface 4a as a part away from the point light transmitting part 13. Specifically, for example, as shown in FIG. 9A, the bottom portion 11 includes a flat plate portion 15 provided with a point light transmitting portion 13 at a substantially center, and an outer peripheral end of the flat plate portion 15 toward the light collection direction D1 side. It has a rising portion 16 that rises, and is convex toward the light source 2 and has a hollow pyramid shape. And as for the bottom part 11, the inner surface 11a is a reflective surface. In other words, the inner surface of the flat plate portion 15 and the rising portion 16 is a reflecting surface.

  The flat plate portion 15 is smaller than the opening end when viewed in the light collecting direction D1, and has a plate surface substantially orthogonal to the light collecting direction D1. And the flat plate part 15 has a space | interval between the surrounding walls 12 of a cylinder in the condensing direction D1, and it stands | starts up between the outer peripheral end of the flat plate part 15, and the edge of the peripheral wall 12 at the bottom part 11 side. They are connected by the part 16.

  The rising portion 16 has a flat plate shape and faces the direction in which the plate surface intersects the plate surface of the flat plate portion 15. The rising portion 16 is inclined toward the rising tip side away from the flat plate portion 15 and closer to the light guide material 4, and the tip is connected to the edge of the peripheral wall 12. In other words, the rising portion 16 is formed so as to be closer to the peripheral wall 12 as it is inclined in the light collecting direction D1 and away from the flat plate portion 15, and has a divergent shape from the flat plate portion 15 toward the peripheral wall 12.

  Therefore, as shown in FIG. 10, the reflecting member 10 reflects the light L1 and the like (light including the opposing light L2 and the like when the light source 2 is arranged facing the light) on the inner surface of the rising portion 16, It is possible to easily enter the light incident surface 4a again (easier to return). The reflecting member 10 has a reflecting surface (inner surface of the rising portion 16) inclined in the condensing direction D1, so that substantially the entire bottom portion 11 is substantially orthogonal to the condensing direction D1 (the entire bottom portion 11 is substantially the same). Compared to the case of a flat plate), the light reflected by the bottom 11 can be easily directed to the light incident surface 4a side.

  In addition, the reflecting member 10 may have a curved surface as well as a bottom 11. For example, in the case shown in FIG. 9B, the reflecting member 10 cut in the light collecting direction D <b> 1 has a U-shaped cross section. It has become. In this case, the bottom 11 has a substantially hemispherical shape that is convex toward the light source 2 and the center of the hemisphere is positioned on a virtual straight line passing through the focal point S1.

  And the point translucent part 13 is provided in the site | part (intersection site | part with the said virtual straight line) on the said virtual straight line which is the front-end | tip part used as the convex part of this hemisphere. Further, the bottom portion 11 changes from an annular shape to a rectangular shape when viewed in the light condensing direction D1 toward the light condensing direction D1 side (light guide material 4 side). The peripheral wall 12 is connected to the edge.

  Therefore, the reflecting member 10 can easily return to the light incident surface 4a by reflecting the light L1 or the like on the inner surface 11a of the bottom portion 11. And when the reflection member 10 has the inner surface 11a (hemispheric inner surface 11a) which approaches the light guide material 4 side, so that the bottom part 11 leaves | separates from the point translucent part 13, when the said bottom part 11 whole is substantially flat plate shape As compared with the above, the light reflected by the bottom portion 11 can be easily directed to the light incident surface 4a side.

  As described above, in this example (third example), the bottom 11 of the reflecting member 10 is shaped so as to be closer to the light incident surface 4a as the part away from the point light transmitting part 13 is reflected at the bottom 11. Light can be easily directed to the light incident surface 4a side. As a result, when returning the light L1 and the like to the light incident surface 4a, the reflecting member 10 is compared with the inner surface 11a until the light returns to the light incident surface 4a as compared with the case where the substantially entire bottom portion 11 is substantially orthogonal. The number of reflections can be easily reduced. Therefore, the lighting device 1 can easily reduce the attenuation of light at the reflecting member 10 such as material absorption or scattering on the reflecting surface, and can easily improve the irradiation efficiency from the light exit surface 4b. .

  Next, an example (fourth example) of the second embodiment will be described. Note that the same components as those in the first embodiment described above are denoted by the same reference numerals, and redundant description is omitted. Hereinafter, features of this example (fourth example) will be described.

  In this example, as shown in FIG. 11, the light guide material 4 has a plate shape having a width in a direction substantially orthogonal to both the light collecting direction D1 and the irradiation direction D2. The light guide member 4 has one light-emitting surface 4b, and the light-entering surface 4a and the light-emitting surface 4b have the same direction and width. In other words, the light guide member 4 has a rod shape having a width on the light incident surface 4a. And as for the light guide material 4, one of the surrounding surfaces which have the width | variety in the same direction as the width | variety of the light-incidence surface 4a among the surrounding surfaces of a stick | rod is the light emission surface 4b. Further, the width is larger than the dimension (width) of the light source 2 and the light collector 3 in the same direction (width direction D3).

  Furthermore, the illuminating device 1 is provided with a plurality of light sources 2 and light collecting units 3 (hereinafter referred to as light source groups). The light source groups are arranged in the direction along the width (width direction D3). The light source sets are arranged in parallel in the light collection direction D1 and directly face the light incident surface 4a in the light collection direction D1, and the focal points S1 of the light source set are positioned side by side in the width direction D3.

  The reflecting member 10 has a width along the width direction D3. In the reflecting member 10, the peripheral wall 12 covers the light incident surface 4a side over substantially the entire width direction D3, and the bottom 11 faces the substantially entire light incident surface 4a, and the inner surface 12a of the peripheral wall 12 and The inner surface 11a of the bottom 11 is a reflecting surface.

  Further, the reflecting member 10 is provided with a point light transmitting portion 13 at a position on an imaginary straight line passing through the focal point S1 of each light collecting portion 3 along the light collecting direction D1 of the bottom portion 11. In other words, the reflection member 10 has the point translucent part 13 for every light source group. Therefore, the light condensed by each condensing part 3 is introduced into the reflecting member 10 (inside the cylinder) via the point translucent part 13 facing (corresponding) for each condensing part 3, The light is incident on the light incident surface 4a by being reflected by the inner surface 12a of the peripheral wall 12 or the like.

  Thus, when the focal point S1 is positioned between the light collecting unit 3 and the light guide member 4, the lighting device 1 reflects light that is difficult to be irradiated on the light incident surface 4a by the inner surface 12a of the peripheral wall 12. The light incident surface 4a can be easily irradiated. Thereby, the illuminating device 1 can make it easy to reduce a decrease in light incident efficiency or the like when the focal point S1 is positioned between the light collecting unit 3 and the light guide member 4, and irradiation from the light exit surface 4b. Efficiency can be easily improved.

  Furthermore, the illuminating device 1 can adjust the position of the bottom part 11 (point translucent part 13) in the condensing direction D1 by slidingly moving the reflecting member 10 with respect to the light guide member 4. Thereby, the illuminating device 1 can make it easy to position the point light transmission part 13 in the focus S1, and can make it easy to introduce the light condensed by the light source 2 into the reflecting member 10.

  Note that the present invention is not limited to the configuration of the above-described embodiment, and within the range intended by the present invention, an appropriate design change or combination of configurations of each example is used. Is possible. The point light transmitting portion 13 may be any material that can transmit light with a dimension such that the edge of the through hole 13a does not block the light from the light collecting portion 3. For example, the point light transmitting portion 13 penetrates as small as a so-called pinhole (needle hole). It may be a hole 13a. In addition, for example, the point light transmitting portion 13 is not limited to the through hole 13a, and is disposed at the focal point S1 so that light from the light collecting portion 3 can be transmitted to the bottom portion 11 by two-color molding or the like. What formed the possible site | part etc. may be used. For example, the point light transmission part 13 may arrange | position optical members, such as a light transmission member and a lens, in the through-hole 13a. Further, for example, the light guide member 4 is not limited to a rectangular bar shape, and the end (second surface 5b) on the opposite side of the light exit surface 4b has a curved shape, or the peripheral surface 5 other than the light exit surface 4b is continuous. It may be one curved surface having a U-shaped cross section.

DESCRIPTION OF SYMBOLS 1 Illuminating device 2 Light source 3 Light-collecting part 4 Light guide material 4a Light incident surface 4b Light-emitting surface 10 Reflective member 11 Bottom part 11a Inner surface of bottom part 12 Peripheral wall 12a Inner surface of peripheral wall 13 Point translucent part 13a Through-hole D1 Condensing direction D2 Irradiation direction D3 width direction S1 focus

Claims (4)

A light source, a light collecting unit for collecting light from the light source, and a light guide material on which the light collected by the light collecting unit is incident from a light incident surface,
A reflecting member having a bottomed cylindrical shape and reflecting the entire inner surface of the peripheral wall of the cylinder on the light incident surface side of the light guide material,
The reflecting member has a point light transmitting part that transmits the light collected by the light collecting part at the focal point of the light collecting part at the bottom,
The reflecting member covers the light incident surface side of the light guide material with the peripheral wall with the bottom portion facing the light incident surface of the light guide material,
Lighting apparatus characterized by being the distance between the bottom portion of the reflecting member and the light guide member as slidable the reflecting member against the light guide member is made variable. The light guide material is formed in the shape of a long bar, both end faces in the longitudinal direction of the light guide material are the light incident surfaces, and the light source, the light condensing unit, and the reflection member are provided for each light incident surface,
The lighting device according to claim 1, wherein the reflecting member has an inner surface of the bottom portion as a reflecting surface in addition to the peripheral wall. The lighting device according to claim 2, wherein the bottom portion has a shape that is closer to the light incident surface as the portion is farther from the point light transmitting portion. A plurality of the light sources are arranged along the light incident surface,
Providing the light condensing part between the light incident surface of each light source;
The lighting device according to any one of claims 1 to 3, wherein each of the point light-transmitting portions is provided at a position of the bottom portion for each of the light collecting portions.

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