JP3209438U - Lighting device - Google Patents

Abstract

Provided is an edge light type illumination device capable of suppressing luminance unevenness in the vicinity of a joint between end surfaces of adjacent light guide plates even in a configuration in which end surfaces of a plurality of light guide plates are connected to each other. An edge light type illumination device in which a light emitting unit is installed on an incident end face of a light guide plate, wherein the light guide plate 2 includes a plurality of concave stripes formed on the bottom surface at a predetermined pitch and parallel to the X-axis direction. And a plurality of ridges parallel to the Y-axis direction formed at a predetermined pitch on the exit surface, and the ridges formed on the bottom surface of the light guide plate 2 have a V-shaped cross section and an apex angle of 65 °. When a plurality of lighting devices are connected along the X-axis direction, a gap of 1 to 2 mm is provided at the joint A between the end surfaces along the Y-axis direction of adjacent light guide plates. The LED 8 is installed at a predetermined interval on the incident end surface 2a side that is held and is not provided near the incident end surface 2a in the vicinity of the joint portion A and is separated from the joint portion A by a predetermined distance (d1). [Selection] Figure 13

Description

  The present invention provides an edge light in which light is incident on a light guide plate from a primary light source such as an LED disposed on at least one side surface of the light guide plate, and light is emitted from one main surface (output surface) of the light guide plate. More specifically, the present invention relates to an edge light type illumination device having a configuration in which the end faces of a plurality of light guide plates are connected to each other to be elongated.

  In large-scale facilities such as department stores, home appliance mass retailers, and shopping centers, escalators are installed between the lower floor and the upper floor to facilitate the user's floor movement.

  Generally, an escalator that descends to the lower floor side and an escalator that rises to the upper floor side are installed so as to overlap in the vertical direction. For this reason, an illuminating device for illuminating the lower side (around the escalator located on the lower side) on the lower surface of the escalator located on the upper side (for example, the escalator rising to the upper floor side) along the longitudinal direction of the escalator (For example, refer to Patent Document 1).

  Patent Document 1 discloses an edge light type lighting device (lighting fixture) provided on the lower surface of an escalator. The edge-light type illumination device allows light to enter the light guide plate from a primary light source (LED or the like) disposed on at least one side surface of the light guide plate, and light from the entire main surface (outgoing surface) of the light guide plate. Can be emitted.

  In addition, in the passage on the same floor, it is necessary to illuminate the user's feet brightly from the viewpoint of safety. Therefore, an illumination device represented by a fluorescent lamp is continuously or discontinuously installed on the ceiling of the passage. Yes.

Japanese Unexamined Patent Application Publication No. 2004-189478 (FIGS. 1, 7 and the like)

  By the way, a transparent plate-shaped light guide plate made of a transparent polymer such as PMMA (polymethyl methacrylate) is installed in the edge light type illumination device, and white dots (scattering dots) are formed on the bottom surface of the light guide plate. By adjusting the size, density, etc. of the dots printed, a part of the light propagating in the light guide plate is scattered when it hits the white dots, and moves in the direction of viewing (exiting surface). Emitted. Further, a diffusion plate is installed on the light exit surface of the light guide plate in order to improve the surface quality by uniformly scattering the light emitted from the light guide plate.

  However, optically, it is difficult to increase the illuminance in the direction directly below the illumination device, so that it is emitted from a direct illumination device, such as a fluorescent lamp, as a light source rather than an edge light illumination device. A configuration in which a decorative plate is placed on the surface side is the mainstream.

  Moreover, the length of the longitudinal direction of an illuminating device is about 1000-1500 mm at the maximum from the handleability at the time of construction. For this reason, when installing an illuminating device in the bottom part of an escalator with a full length of about 10-15 m, for example, it is necessary to connect and elongate several illuminating devices over the full length of an escalator.

  By the way, when the above-described fluorescent lamp is used as a direct illumination system, there are metal caps at both ends of the fluorescent lamp, so that it cannot emit light here. For this reason, the joint (joint) between adjacent illuminating devices becomes a dark part, and looks worse.

  Therefore, the present invention is capable of brightly illuminating the direct light direction even in the case of an edge light type illumination device, and even in a configuration in which the end surfaces of a plurality of light guide plates are connected to each other, the joint between the end surfaces of adjacent light guide plates is used. An object of the present invention is to provide an edge light type illumination device capable of suppressing uneven luminance in the vicinity.

  In order to achieve the above object, in the illumination device according to claim 1, a primary light source is installed on at least one side surface of a light guide plate made of a resin material, and the light guide plate faces an emission surface and the emission surface. An edge light type illumination device having an incident end face for allowing light emitted from the primary light source provided on a bottom surface and at least one side surface to be incident, and is configured by an X axis and a Y axis orthogonal to the X axis The primary light source is arranged parallel to the X axis, the normal line of the XY plane being the Z axis, the light guide plate is arranged parallel to the XY plane, and the incident end face of the light guide plate is The light guide plate is parallel to the XZ plane, and the light guide plate has a plurality of concave stripe patterns parallel to the X-axis direction formed at a predetermined pitch on the bottom surface, and a Y-axis direction formed at a predetermined pitch on the emission surface. The light guide plate having a plurality of parallel ridge patterns The concave stripe pattern formed on the bottom surface has a V-shaped cross section and an apex angle of 65 ° to 105 °, and the adjacent illumination device is connected when a plurality of the illumination devices are connected along the X-axis direction. The primary light source is not provided in the vicinity of the side surface of the light guide plate along the X-axis direction of the joint portion between the light guide plates of the illumination device, and the light guide plate of the light guide plate along the X-axis direction separated from the joint portion by a predetermined distance is provided. The primary light source is installed on a side surface at a predetermined interval.

  In the illumination device according to claim 2, a primary light source is installed on at least one side surface of a light guide plate made of a resin material, and the light guide plate has an emission surface, a bottom surface facing the emission surface, and at least one side surface. An illuminating device of an edge light system having an incident end face for allowing light emitted from the provided primary light source to enter, and a normal line of an XY plane composed of an X axis and a Y axis orthogonal to the X axis Is the Z axis, the primary light source is arranged parallel to the X axis, the light guide plate is arranged parallel to the XY plane, and the incident end face of the light guide plate is parallel to the XZ plane. And the light guide plate includes a plurality of concave stripe patterns parallel to the X-axis direction formed on the bottom surface at a predetermined pitch and a plurality of convex stripe patterns parallel to the Y-axis direction formed on the emission surface at a predetermined pitch. And the concave formed on the bottom surface of the light guide plate. The pattern has a V-shaped cross section and an apex angle of 120 ° to 150 °. When a plurality of the lighting devices are connected along the X-axis direction, the pattern is formed between adjacent light guide plates of the lighting devices. The primary light source is not provided in the vicinity of the side surface of the light guide plate along the X-axis direction of the joint portion, and the primary light source is disposed at a predetermined interval on the side surface of the light guide plate along the X-axis direction that is a predetermined distance away from the joint portion. It is characterized by being installed in.

  The illumination device according to claim 3 is characterized in that the convex stripe pattern formed on the exit surface of the light guide plate has a trapezoidal shape, a lenticular lens shape, or a parabolic shape in cross section.

  The illumination device according to claim 4 has a reflection sheet that reflects light on a bottom surface side of the light guide plate, and a diffusion sheet that uniformly diffuses light on an emission surface side of the light guide plate. It is characterized by that.

  The illuminating device of Claim 5 has the reflective sheet which reflects light in the bottom face side of the said light-guide plate, It is characterized by the above-mentioned.

  The lighting device according to claim 6, wherein a distance from an intermediate portion along the X-axis direction of the joint portion to the primary light source provided at a position closest to the joint side of the side surface of one of the adjacent light guide plates Is characterized by being 1 to 5 mm.

  According to the lighting device according to the present invention, when a plurality of lighting devices are connected along the X-axis direction, in the vicinity of the side surface of the light guide plate along the X-axis direction of the joint portion between the light guide plates of adjacent lighting devices. Even if the primary light source is installed at a predetermined interval on the side surface of the light guide plate along the X-axis direction that is a predetermined distance away from the joint portion without providing a primary light source, Interference between the end faces of the adjacent light guide plates at the joint is prevented, and the brightness near the side surface on the side where the primary light source is provided is suppressed near the joint, so that the joint near the joint is suppressed. The luminance unevenness along the direction can be reduced.

The schematic perspective view which shows the lower surface side of the escalator provided with the illuminating device which concerns on embodiment of this invention. The disassembled perspective view which shows the illuminating device of the edge light system which concerns on embodiment of this invention. FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. The schematic side view which shows the short side of the illuminating device which concerns on this embodiment. In the illumination device according to the present embodiment, the exit surface of the light guide plate when the apex angle of the V-shaped cross-section formed on the bottom surface of the light guide plate is 70 ° and no diffusion sheet is provided on the exit surface side The figure which showed the measurement result of the luminous intensity distribution of the light radiate | emitted from. (A) is a figure which shows the output surface side of the light-guide plate of the illuminating device which concerns on this embodiment, (b) is the BB sectional drawing of Fig.6 (a). In the illumination device according to the present embodiment, the exit surface of the light guide plate when the apex angle of the V-shaped cross-section formed on the bottom surface of the light guide plate is 70 ° and a diffusion sheet is provided on the exit surface side The figure which showed the measurement result of the luminous intensity distribution of the light radiate | emitted from. The schematic side view which shows the short side of the illuminating device which concerns on the modification of this embodiment. In the illuminating device according to the modification of the present embodiment shown in FIG. 8, the light emitted from the exit surface of the light guide plate when the apex angle of the V-shaped recess formed on the bottom surface of the light guide plate is changed. The figure which showed the measurement result of the luminous intensity distribution. (A) is a figure which shows the output surface side of the light-guide plate of the illuminating device which concerns on the modification of this embodiment, (b) is CC sectional view taken on the line of Fig.10 (a). In the lighting device according to the modification of the present embodiment, the light guide plate when the vertical angle of the V-shaped cross-section formed on the bottom surface of the light guide plate is 130 ° and the diffusion sheet is provided on the exit surface side The figure which showed the measurement result of the luminous intensity distribution of the light radiate | emitted from the output surface. The schematic sectional drawing which shows the state which hold | maintained the illuminating device which concerns on embodiment of this invention on the lower surface side surface of the escalator. The top view which shows the seam vicinity between the end surfaces of each adjacent light-guide plate in embodiment (Example 1) of this invention. The top view which shows the seam vicinity between the end surfaces of each adjacent light-guide plate in the comparative example 1. FIG. It is the figure which showed the measurement result of the brightness | luminance along the longitudinal direction of the light-guide plate of the vicinity of the seam between the end surfaces of each adjacent light-guide plate in embodiment (Example 1) of this invention, (a) is the clearance gap between seams. (B) is the measurement result when the seam gap is 2 mm, and (c) is the measurement result when the seam gap is 5 mm. It is the figure which showed the measurement result of the brightness | luminance along the longitudinal direction of the light-guide plate of the vicinity of the joint between the end surfaces of each adjacent light-guide plate in the comparative example 1, (a) is a measurement result when the clearance gap of a joint is 0 mm (B) is the measurement result when the gap of the seam is 2 mm, and (c) is the measurement result when the gap of the seam is 5 mm. (A) is a side view which shows the seam vicinity between the end surfaces of each adjacent light-guide plate in the comparative example 2, (b) is the top view. (A) is a side view which shows the joint vicinity between the end surfaces of each adjacent light-guide plate in the comparative example 3, (b) is the top view. It is the figure which showed the measurement result of the brightness | luminance along the longitudinal direction of the light-guide plate of the vicinity of the seam of the edge surfaces of each adjacent light-guide plate in the comparative example 2, (a) is a measurement result when the width | variety of a seam is 10 mm. , (B) are measurement results when the width of the seam is 5 mm. It is the figure which showed the measurement result of the brightness | luminance along the longitudinal direction of the light-guide plate of the vicinity of the joint between the end surfaces of each adjacent light-guide plate in the comparative example 3, (a) is a measurement result when the width | variety of a joint is 10 mm. , (B) are measurement results when the width of the seam is 5 mm. (A) is a side view showing the vicinity of a joint between end faces when adjacent light guide plates are held at a predetermined angle in the first modification of the embodiment of the present invention, and (b) is a plan view thereof. . (A) is a side view showing the vicinity of a seam between end faces when adjacent light guide plates are held at a predetermined angle in a second modification of the embodiment of the present invention, and (b) is a plan view thereof. . The figure which showed the measurement result of the brightness | luminance along the longitudinal direction of the light-guide plate of the 1st modification of embodiment of this invention shown in FIG. 21 near the seam between the end surfaces of each adjacent light-guide plate.

  FIG. 1 is a schematic perspective view showing a lower surface side of an escalator provided with a lighting device according to an embodiment of the present invention. In the illumination device according to the present embodiment, light enters a light guide plate from a primary light source (LED) disposed on at least one side surface of the light guide plate, and one main surface (outgoing surface) of the light guide plate as a whole. This is an edge light type illumination device that emits planar light by emitting light from the light source.

  As shown in FIG. 1, for example, the first escalator 10 for descending to the lower floor side and the second escalator 11 for climbing to the upper floor side are installed so as to overlap in the vertical direction, and are positioned on the upper side. On both sides of the lower surface 11a of the second escalator 11, there is an edge light type illumination device (hereinafter simply referred to as “illumination device”) 1 for illuminating the periphery of the first escalator 10 on the lower side thereof. 11 are installed so as to be connected in plural along the longitudinal direction.

  In this way, by connecting the end surfaces of the plurality of lighting devices 1 along the longitudinal direction of the second escalator 11, it is thinned to emit long planar light along the longitudinal direction of the second escalator 11. The long illuminating device is configured.

(Configuration of lighting device 1)
FIG. 2 is an exploded perspective view showing the lighting device according to the embodiment of the present invention, and FIG. 3 is a cross-sectional view taken along line AA of FIG. In the illumination device according to the present embodiment, the normal line of the XY plane composed of the X axis and the Y axis orthogonal to the X axis is the Z axis, and the Z axis direction is the light emission direction.

  As shown in FIGS. 2 and 3, the lighting device 1 according to the present embodiment includes a light guide plate 2 that is a transparent structure formed of a transparent resin (for example, acrylic resin), and the Y-axis direction of the light guide plate 2. Of the light emitting unit 3 disposed on one end face (hereinafter referred to as “incident end face”) 2a side, the reflection sheet 4 disposed on the back side (hereinafter referred to as “bottom face”) 2b side of the light guide plate 2, and the light guide plate 2 A diffusion sheet 5 installed on the front surface (hereinafter referred to as “emission surface”) 2c side is provided as a main constituent member.

  As shown in FIG. 2, the light guide plate 2 of the illumination device 1 has a long side in the X-axis direction, and the light emitting unit 3 is arranged along one long side (X-axis direction). In addition, as shown in FIG. 1, when installing this illuminating device 1 on both sides of the lower surface 11a of the 2nd escalator 11, the reflective sheet 4 side (bottom surface 2b side) is located in the surface of the lower surface 11a side, Light is emitted from the diffusion sheet 5 side (emission surface 2c side) downward (first escalator 10 side).

  On the bottom surface 2b of the light guide plate 2, a plurality of recesses 6 extending in the X-axis direction (long side direction) are formed at a predetermined pitch. A plurality of patterns of ridges 7 extending in the Y-axis direction (short side direction) are formed at a predetermined pitch on the emission surface 2c of the light guide plate 2 (details of the light guide plate 2 will be described later).

  The light emitting unit 3 as a primary light source is disposed along the X-axis direction on the incident end surface 2a of the light guide plate 2, and within the light emitting unit 3, a predetermined interval linearly along the X-axis direction of the light guide plate 2 A plurality of LEDs 8 as light sources are arranged. The arrangement interval of the LEDs 8 is, for example, about several mm to 20 mm. As this LED 8, white light (white LED) is mainly used.

  Light emitted from each LED (light source) 8 of the light emitting unit 3 is incident in the Y-axis direction in the light guide plate 2 from the incident end surface 2 a of the light guide plate 2.

  The reflection sheet 4 has a function of causing the light emitted from the bottom surface 2 b of the light guide plate 2 out of the light incident from the incident end surface 2 a side of the light guide plate 2 to enter the light guide plate 2 again. It is desirable that the reflection sheet 4 has a reflectance of 95% or higher because of high light utilization efficiency. Examples of the material of the reflection sheet 4 include metal foils such as aluminum, silver, and stainless steel, white coating, and foamed PET (polyethylene terephthalate) resin.

  The diffusion sheet 5 installed on the light emission surface 2c side, which is the front surface side of the light guide plate 2, makes the light emitted from the light emission surface 2c of the light guide plate 2 moderately uniform, suppresses unevenness in brightness and darkness, and improves the appearance. It has a function to make it.

  Since the lighting device 1 installed on the lower surface of the escalator as described above, the ceiling surface of an office or a house, etc. directly recognizes the light emitting surface of the lighting device 1, the appearance quality is emphasized. One or more sheets may be used. The diffusion sheet 5 may be a plate-like material (for example, PMMA, PC, etc.) made of a resin having diffusibility, or may be a protective cover shape obtained by thermoforming these plates into a three-dimensional shape. Good.

  Note that the installation of the diffusion sheet 5 on the light exit surface 2c side of the light guide plate 2 is not essential, and the diffusion sheet 5 may be omitted depending on the installation location, application, and the like of the lighting device 1.

  Moreover, in order to arrange | position the several illuminating devices 1 along the longitudinal direction of the 2nd escalator 11 (both sides of the lower surface 11a) shown in FIG. 1, it is each light guide plate of the illuminating device 1 which adjoins. The two end surfaces are connected to each other (the detailed configuration of the vicinity of the joint between the end surfaces of the respective light guide plates 2 of the adjacent lighting devices 1 that is a feature of the present invention will be described later). The lighting device 1 may be used in a state where a plurality of lighting devices 1 are integrated.

(Configuration of light guide plate 2)
As shown in FIG. 2, the bottom surface 2b of the light guide plate 2 is formed with recesses 6 formed at a predetermined pitch. The recess 6 has a V-shaped (V-groove) cross-sectional shape and extends in the X-axis direction. As shown in FIG. 4, in this embodiment, the apex angle (θ) of the recess 6 having a V-shaped cross section is set in a range of 65 ° to 105 °, and more preferably in a range of 70 ° to 100 °. Is set to Moreover, the height (depth) of the concave strip 6 is set within a range of about 0.001 to 0.1 mm, and more preferably within a range of 0.003 to 0.02 mm.

  In the illuminating device 1 shown in FIG. 2, among the light incident from the incident end surface 2 a side of the light guide plate 2, the main light emitted from the output surface 2 c of the light guide plate 2 is formed on the bottom surface 2 b of the light guide plate 2. The cross-sectional shape is the light that is totally reflected by the inclined surface of the V-shaped concave strip 6 and is emitted in the substantially front direction (Z-axis direction) of the emission surface 2c.

  Further, in the present embodiment, ridges 7 having a lenticular lens cross-sectional shape are formed at a predetermined pitch on the emission surface 2c of the light guide plate 2 and extend in the Y-axis direction. The ridges 7 of the emission surface 2c transmit and emit light that is emitted substantially in the front direction (Z-axis direction) of the emission surface 2c, and from the concave 6 side of the bottom surface 2b to the substantially front direction (Z The light incident on the ridge 7 at an angle other than (axial direction) is totally reflected within the ridge 7 and returned to the light guide plate 2. Then, the cross-sectional shape formed on the bottom surface 2b of the light guide plate 2 is again totally reflected by the inclined surface of the V-shaped concave strip 6, and is emitted in a substantially front direction (Z-axis direction) of the emission surface 2c.

  Thus, the luminous intensity of the light emitted from the substantially front direction (Z-axis direction) of the emission surface 2c can be improved by the ridge 7 having a lenticular lens shape in cross section formed on the emission surface 2c of the light guide plate 2. .

  In addition, although the cross-sectional shape of the protruding item | line 7 formed in the output surface 2c of the light-guide plate 2 was a lenticular lens shape in this embodiment, a cross-sectional shape may be trapezoid shape or parabolic shape besides this.

  FIG. 5 shows a cross section formed on the bottom surface 2b of the light guide plate 2 with the aspect ratio of the lenticular lens-shaped ridges 7 formed on the light exit surface 2c of the light guide plate 2 set to 20%. It is a measurement result of the luminous intensity distribution of the light emitted from the emission surface 2c of the light guide plate 2 when the apex angle (θ) of the letter-shaped recess 6 is set to 70 °.

  The aspect ratio is defined as r / 2R (%), where R is the radius of a circle tracing the vertical cross section of the lenticular lens and r is the distance from the apex of the arc forming the lenticular lens to the chord. In this measurement, the diffusion sheet 5 on the emission surface 2c side is removed.

  In the measurement result of the luminous intensity distribution shown in FIG. 5, as shown in FIGS. 6A and 6B, the central portion c of the light guide plate 2 is a measurement point, and the front direction of the emission surface 2 c of the light guide plate 2 ( (Z-axis direction) is an emission angle of 0 °, and on the ZY plane, the angle between the Z axis and the + (plus) Y axis is -90 °, and the angle between the Z axis and the-(minus) Y axis is + 90 °. FIG. 6B is a cross-sectional view taken along the line BB in FIG. In FIG. 6B, the direction of arrow A is the emission direction of the light (illumination light) emitted from the emission surface 2c, and slightly toward the light emitting unit 3 with respect to the front direction (Z-axis direction) of the emission surface 2c. It is.

  In this way, a concave strip 6 having a V-shaped cross section with an apex angle of 70 ° is formed on the bottom surface 2b of the light guide plate 2, and the cross section of the light exit surface 2c of the light guide plate 2 is a lenticular lens shape (or a trapezoidal cross section). Or parabolic ridges 7 are formed, planar light is emitted from the exit surface 2c of the light guide plate 2, and light having a high intensity is emitted in a substantially front direction (Z-axis direction) of the exit surface 2c. Can be made.

  When the diffusion sheet 5 is arranged on the light exit surface 2c side of the light guide plate 2 under the same conditions (see FIG. 2), as shown in FIG. 7, in the substantially front direction (Z-axis direction) of the light exit surface 2c. The emitted light can be appropriately diffused, the luminous intensity distribution can be smoothed, and light having a high luminous intensity can be emitted in a substantially front direction (Z-axis direction) of the emission surface 2c.

  In the measurement of the luminous intensity distribution described above, the apex angle of the recess 6 having a V-shaped cross section formed on the bottom surface 2b of the light guide plate 2 is set to 70 °, but the apex angle of the recess 6 is set to 65 ° to 105 °. Even in the case where the range is set to about °, planar light is similarly emitted from the emission surface 2c of the light guide plate 2, and light having high luminous intensity is emitted substantially in the front direction (Z-axis direction) of the emission surface 2c. I was able to.

  Therefore, by arranging and connecting a plurality of the lighting devices 1 on both sides of the lower surface 11a of the second escalator 11, light having a high intensity (from the emission surface 2c of each lighting device 1 to the first escalator 10 below ( Illumination light) can be emitted to illuminate the periphery of the first escalator 10 brightly.

  Moreover, as shown in FIG. 1, in this embodiment, the illuminating device 1 is provided in the both sides of the lower surface 11a of the 2nd escalator 11 located in an upper side. For this reason, in order to illuminate the vicinity of the center of the lower first escalator 10 more brightly, it has a high directivity from the exit surface of the illumination device to the vicinity of the center of the first escalator 10 (anisotropy in the luminous intensity distribution). It is necessary to emit light having a high luminous intensity.

  Therefore, when emitting light having anisotropy in the luminous intensity distribution and high luminous intensity from the emission surface of the illuminating device, it is formed on the bottom surface 2b of the light guide plate 2 as in the illuminating device 1a shown in FIG. The apex angle (θ) of the groove 6 having a V-shaped cross section is set in the range of 120 ° to 150 °. Other configurations are the same as those of the lighting device 1 shown in FIGS.

  FIG. 9 shows a V-shape formed on the bottom surface 2b of the light guide plate 2 by setting the aspect ratio of the lenticular lens-shaped ridges 7 formed on the light exit surface 2c of the light guide plate 2 to 20%. It is a measurement result of the luminous intensity distribution of the light radiate | emitted from the output surface 2c of the light-guide plate 2, when changing the apex angle ((theta)) of the groove 6 of this (it changes between 120 degrees-150 degrees).

  This aspect ratio is defined as r / 2R (%), where R is the radius of a circle tracing the vertical cross section of the lenticular lens and r is the distance from the apex of the arc forming the lenticular lens to the chord. In this measurement, the diffusion sheet 5 on the emission surface 2c side is removed.

  In the measurement result of the luminous intensity distribution shown in FIG. 9, as shown in FIGS. 10A and 10B, the central portion c of the light guide plate 2 is a measurement point, and the front direction of the light exit surface 2 c of the light guide plate 2 ( In the ZY plane, the light emitting unit 3 side in the Y axis direction is −90 ° and the side opposite to the light emitting unit 3 in the Y axis direction is + 90 °. In addition, FIG.10 (b) is CC sectional view taken on the line of Fig.10 (a). In FIG. 10B, the direction of arrow A is the emission direction of light (illumination light) from the emission surface 2c (the obliquely downward direction opposite to the light emitting unit 3).

  In FIG. 9, a is the apex angle (θ) of the groove 6 is 120 °, b is the apex angle (θ) of the groove 6 is 130 °, c is the apex angle (θ) of the groove 6 is 140 °, d Is a luminous intensity distribution when the apex angle (θ) of the concave strip 6 is 150 °, and is normalized by the maximum luminous intensity value when the apex angle (θ) of the concave strip 6 is 120 °.

  As is apparent from the measurement results shown in FIG. 9, the luminous intensity distribution is obtained by setting the apex angle (θ) of the V-shaped concave strip 6 formed on the bottom surface 2b of the light guide plate 2 to 120 ° to 150 °. Light (illumination light) having anisotropy and high luminous intensity can be emitted from the emission surface 2c.

  When the diffusion sheet 5 is arranged on the light exit surface 2c side of the light guide plate 2 under the same conditions (see FIG. 8), the direction from the light exit surface 2c of the light guide plate 2 to the direction of arrow A (the diagonally lower side opposite to the light emitting unit 3). When the luminous intensity distribution of the light (illumination light) emitted in the lateral direction was measured, a measurement result as shown in FIG. 11 was obtained.

  In the measurement of the luminous intensity distribution, the apex angle (θ) of the V-shaped recess 6 formed on the bottom surface 2b of the light guide plate 2 is 130 °, and the lenticular lens shape formed on the exit surface 2c of the light guide plate 2 is used. The aspect ratio of the ridges 7 is set to 20%.

  In the measurement result of the light intensity distribution shown in FIG. 11, the central portion c (see FIG. 10A) of the light guide plate 2 is the measurement point, and the light is emitted in the front direction (Z-axis direction) of the light exit surface 2 c of the light guide plate 2. The angle is 0 °, and in the ZY plane, the light emitting unit 3 side in the Y axis direction is −90 °, and the opposite side to the light emitting unit 3 in the Y axis direction is + 90 °.

  As is apparent from the measurement results shown in FIG. 11, by disposing the diffusion sheet 5 on the light exit surface 2c side of the light guide plate 2, the light emitted from the light exit surface 2c is diffused and the light intensity distribution having anisotropy is obtained. The range can be smoothed.

  Therefore, by arranging a plurality of the lighting devices 1a on both sides of the lower surface 11a of the second escalator 11, a particularly high directivity from the exit surface of the lighting device 1a to the vicinity of the center of the first escalator 10 below. It is possible to emit light having a high luminous intensity (having anisotropy in the luminous intensity distribution) and illuminate the vicinity of the center of the first escalator 10 more brightly.

(Detailed configuration near the joint between the end faces of the adjacent light guide plates 2)
As shown in FIG. 1, a plurality of lighting devices 1 (the lighting device 1 a in FIG. 8 is the same) are arranged on both sides of the lower surface 11 a of the second escalator 11 along the longitudinal direction of the second escalator 11. In order to obtain a long illuminating device, the end faces of the respective light guide plates 2 of the adjacent illuminating devices 1 are connected and held.

  For example, as shown in FIG. 12, this lighting device 1 (the same applies to the lighting device 1 a in FIG. 8) is attached along the longitudinal direction of the second escalator 11 on both sides of the lower surface 11 a of the second escalator 11. It is held and fixed in the holding member 12, and a plurality of lighting devices 1 are arranged along the longitudinal direction of the second escalator 11. In addition, the reflection sheet 4 on the bottom surface 2b side and the diffusion sheet 5 on the emission surface 2c side of the light guide plate 2 are formed long along the longitudinal direction of the second escalator 11, and end surfaces of the adjacent light guide plates 2 It is preferable to arrange so as to cover the gap (seam portion).

  In FIG. 1, a solid line is drawn between the end surfaces (joint portions) of the respective light guide plates 2 of the adjacent lighting devices 1, but the reflection sheet 4 and the diffusion sheet 5 on the exit surface 2 c side are connected to the adjacent light guide plates 2. By arranging so as to cover between the end faces (joint portion), the joint portion is actually very difficult to see from the outside.

  However, depending on the construction method and the like, any of the joints of the reflection sheet 4, the light guide plate 2, and the diffusion sheet 5 may overlap. In particular, the joints of the light guide plate 2 and the diffusion sheet 5 do not overlap. Is preferable.

  As shown in FIG. 13, in the present embodiment, the end surfaces of the adjacent light guide plates 2 are connected with a predetermined gap d. When the length of each light guide plate 2 in the longitudinal direction is L, the gap d is preferably about 0.001 · L (mm) in consideration of the linear expansion of the light guide plate 2. For example, in the case where L is 1200 mm, it is preferable to arrange them with a gap of 1 to 2 mm. In the present embodiment, both side corners in the vicinity of the end surface of one of the light guide plates 2 among the adjacent end surfaces of the light guide plates 2 so that elongation by linear expansion occurs on one side in the longitudinal direction of the light guide plate 2 ( Or the corner | angular part of one side) is being fixed by the fixing member (not shown) in the said holding member 12 (refer FIG. 12).

  Therefore, in the adjacent light guide plate, the light guide plate can be brought into close contact (no gap) at a location where the expansion due to linear expansion can be opposed (for example, bent at a predetermined angle in FIG. 1 described later). Connection at seam A).

  On one side surface (incident end surface 2a) of the light guide plate 2, LEDs 8 as light sources are arranged at a predetermined interval. Specifically, as shown in FIG. 13, there is no LED (light source) in the vicinity of the side surface of the joint portion A between the end surfaces of the adjacent light guide plates 2, and from the end surfaces (joint portions A) of the adjacent light guide plates 2. LED8 is arrange | positioned at the side surface of the position a little away.

  As shown in FIG. 13, a predetermined clearance (q) is usually provided between the incident end face 2 a of the light guide plate 2 and the light emitting surface of the LED 8, and at this time, d <b> 1 (joint portion A in FIG. 13). The distance between the LED 8 closest to the intermediate portion along the light guide plate longitudinal direction and the joint portion A side is set to d / 2 + q ≦ d1 <d2.

  For example, when the gap d between the end surfaces of the adjacent light guide plates 2 (the joint portion A) is 1 to 2 mm, the intermediate portion along the light guide plate longitudinal direction of the joint portion A and the joint A side are closest to each other. The distance d1 between the LEDs 8 is set to 0.8 to 5 mm. The distance d2 between the LEDs 8 arranged on the side surface (incident end surface 2a) of the light guide plate 2 is 2 to 10 mm.

  As described above, in this embodiment, the gap d between the end surfaces of the adjacent light guide plates 2 (the seam portion A) is set to 1 to 2 mm, and no LED (light source) is disposed near the side surface of the seam portion A. The distance d1 is set to be about half of the distance d2.

  Next, evaluation of the effect of reducing luminance unevenness in the vicinity of the joint A by the joint configuration (see FIG. 13) between the end faces of each light guide plate 2 of the present embodiment described above is described in the following Example 1 and Comparative Example 1. Based on ~ 3. In Example 1 and Comparative Examples 1 to 3 below, the V-shaped concave stripe described above is formed on the bottom surface of the light guide plate 2 (longitudinal length is 1000 mm, width is 200 mm, and thickness is 3 mm). For example, lenticular lens-shaped ridges are respectively formed, a reflection sheet is disposed on the bottom surface side, and a diffusion sheet is disposed on the emission surface side.

Example 1
As shown in FIG. 13, in Example 1, the gap d between the end surfaces of the adjacent light guide plates 2 (the joint portion A) is 0 to 5 mm, the intermediate portion of the joint portion A and the side surface of the light guide plate 2 (incident). The distance d1 between the LEDs 8 arranged on the end surface 2a) side was set to 3 mm, and the distance d2 between the LEDs 8 arranged on the side surface (incident end surface 2a) of the light guide plate 2 was set to 6.4 mm.

(Comparative Example 1)
As shown in FIG. 14, in Comparative Example 1, the gap d between the end surfaces of the adjacent light guide plates 2 (the joint portion A) is set to 0 to 5 mm, and the LED 8 is provided near the side surface on the incident end surface 2 a side of the joint portion A. The distance d2 between the LEDs 8 arranged near the side surface of the joint A and the LEDs 8 arranged on the incident end surface 2a of the light guide plate 2 was set to 6.4 mm. A predetermined clearance (q) is provided between the incident end surface 2 a of the light guide plate 2 and the light emitting surface of the LED 8.

15A, 15 </ b> B, and 15 </ b> C show the case where each LED 8 disposed on the side surface (incident end surface 2 a) of the light guide plate 2 is caused to emit light and light enters the light guide plate 2 in the first embodiment. It is the measurement result of the brightness | luminance in the seam part A vicinity of the light radiate | emitted from the output surface side (surface side of the light-guide plate 2 of FIG. 13). 15A, 15B, and 15C, the horizontal axis indicates the measurement range along the longitudinal direction of the light guide plate 2 including the vicinity of the joint A (the range of L1 to L2 in FIG. 13), and the vertical axis. Is the luminance (cd / m ² ).

  FIG. 15A shows an example in which the gap d between the end surfaces of the adjacent light guide plates 2 (the joint A) is 0 mm (there is no gap in the joint A). FIG. When the gap d between the two end surfaces (the joint portion A) is 2 mm, FIG. 15C shows the case where the gap d between the end surfaces of the adjacent light guide plates 2 (the joint portion A) is 5 mm. In FIGS. 15A, 15B and 15C, a is a measurement result of luminance at a position 6 mm inward slightly from the incident end face 2a side (LED8 side) of the light guide plate 2, and b is the light guide plate. 2 is a measurement result of luminance at a position that is 1/4 of the short side length from the incident end surface 2a (50 mm from the light incident end surface), and c is a substantially intermediate position (from the light incident end surface) in the short side direction of the light guide plate 2. 100 mm) is a measurement result of luminance.

  As in Example 1, when the LED 8 is not installed between the end faces (the joint A) of the light guide plates 2 and the LED 8 is installed across the joint A, the gap d is set to 0 mm and 2 mm. (FIGS. 15A and 15B), the luminance unevenness along the seam direction in the vicinity of the seam portion A was small.

  If the gap d between the end surfaces of the adjacent light guide plates 2 (the joint portion A) is 0 mm (FIG. 15A), the light guide plate 2 may be deformed by linear expansion in the longitudinal direction. It is not preferable in terms of structure.

  Further, when the gap d between the end surfaces of the adjacent light guide plates 2 (the joint portion A) is 5 mm (FIG. 15C), the luminance near the joint portion A is lower than when the gap d is 2 mm. Thus, the vicinity of the seam portion A appears darker (the luminance unevenness along the seam direction in the vicinity of the seam portion A was small).

  Further, when the gap d between the end surfaces of the adjacent light guide plates 2 (the joint portion A) was 3 mm, the measurement result was substantially the same as that shown in FIG.

16A, 16 </ b> B, and 16 </ b> C, in Comparative Example 1, each LED 8 disposed on the side surface (incident end surface 2 a) side of the light guide plate 2 is caused to emit light and light is incident on the light guide plate 2. It is a measurement result of the brightness | luminance in the seam part A vicinity of the light radiate | emitted from the output surface side (surface side of the light-guide plate 2 of FIG. 14). 16A, 16B, and 16C, the horizontal axis indicates the measurement range along the longitudinal direction of the light guide plate 2 including the vicinity of the joint A (the range of L1 to L2 in FIG. 14), and the vertical axis. Is the luminance (cd / m ² ).

  FIG. 16A shows an example in which the gap d between the end surfaces of the adjacent light guide plates 2 (the seam portion A) is 0 mm (there is no gap in the seam portion A). When the gap d between the end surfaces of the optical plate 2 (the joint portion A) is 2 mm, FIG. 16C shows the case where the gap d between the end surfaces of the adjacent light guide plates 2 (the joint portion A) is 5 mm. 16A, 16B, and 16C, a is a measurement result of luminance at a position 6 mm inward from the incident end face 2a side (LED8 side) of the light guide plate 2, and b is a light guide plate. 2 is a measurement result of luminance at a position that is 1/4 of the short side length from the incident end surface 2a (50 mm from the light incident end surface), and c is a substantially intermediate position (from the light incident end surface) in the short side direction of the light guide plate 2. 100 mm) is a measurement result of luminance.

  When the LED 8 is disposed on the joint A on the incident end face 2a side of the light guide plate 2 as in Comparative Example 1, the luminance distribution at the position a close to the incident end face 2a (FIGS. 16A and 16B). In (c) a), the luminance is high protruding from the seam portion A, and at b and c far from the light incident end face 2a, the luminance in the vicinity of the seam portion A is lowered and darkened. The brightness unevenness along the seam direction is large.

(Comparative Example 2)
17A is a side view showing the vicinity of the end face (joint portion A) of each adjacent light guide plate 2 in Comparative Example 2, and FIG. 17B is the end face of each adjacent light guide plate 2 in Comparative Example 2 (FIG. 17B). It is a top view which shows the seam part A) vicinity.

  As shown in FIGS. 17 (a) and 17 (b), in Comparative Example 2, the flat end portions 2d and 2e are formed by cutting out the upper and lower ends of the adjacent light guide plates 2 by half the thickness. Yes. The width of the semi-thick planar end portions 2d, 2e in the longitudinal direction (left-right direction in the figure) is 10 mm. At the joint portion A, the front end sides of the planar end portions 2d and 2e are overlapped and brought into contact with each other. Further, there is no LED (light source) near the side surface of the joint portion A (contact portion on the front end side of the planar end portions 2d and 2e) between the end surfaces (planar end portions 2d and 2e) of the adjacent light guide plates 2 and adjacent to each other. LED8 is arrange | positioned at the side surface (incident end surface 2a) of the position a little away from the end surface (joint part A) of each light-guide plate 2 to perform. In addition, the distance between each LED8 arrange | positioned at the incident end surface 2a of the light-guide plate 2 was set to 9.4 mm.

(Comparative Example 3)
18A is a side view showing the vicinity of the end surface (joint portion A) of each adjacent light guide plate 2 in Comparative Example 3, and FIG. 18B is the end surface of each adjacent light guide plate 2 in Comparative Example 3 ( It is a top view which shows the seam part A) vicinity.

  As shown in FIGS. 18 (a) and 18 (b), in Comparative Example 3, the upper and lower sides of the end surfaces of the adjacent light guide plates 2 are cut out by half the thickness to form planar end portions 2d and 2e. Yes. The width of the semi-thick planar end portions 2d, 2e in the longitudinal direction (left-right direction in the figure) is 10 mm. At the joint portion A, the front end sides of the planar end portions 2d and 2e are overlapped and brought into contact with each other. And LED8 is arrange | positioned in the side surface vicinity of the joint part A (contact part of the front end side of the plane edge parts 2d and 2e) of the edge surfaces (plane edge part 2d, 2e) of each adjacent light-guide plate 2. As shown in FIG. In addition, the distance between each LED8 arrange | positioned at the incident end surface 2a of the light-guide plate 2 was set to 9.4 mm.

19 (a) and 19 (b) are emission surfaces when the LEDs 8 arranged on the side surface (incident end surface 2a) of the light guide plate 2 emit light and light enters the light guide plate 2 in Comparative Example 2. FIG. It is the measurement result of the brightness | luminance in the seam part A vicinity of the light radiate | emitted from the side (surface side of the light-guide plate 2 of Fig.17 (a), (b)). 19 (a) and 19 (b), the horizontal axis represents the measurement range along the longitudinal direction of the light guide plate 2 including the vicinity of the joint A (the range of L1 to L2 in FIG. 17 (b)), and the vertical axis represents It is luminance (cd / m ² ).

  FIG. 19A shows a case where the width D (see FIG. 17A) of the joint portion A between the end surfaces (plane end portions 2d and 2e) of the adjacent light guide plates 2 is 10 mm. This is when the width D of the joint A is 5 mm. In FIGS. 19A and 19B, a is a measurement result of luminance at a position 6 mm inward slightly from the incident end face 2a side (LED8 side) of the light guide plate 2, and b is an incident end face of the light guide plate 2. As a result of measuring the luminance at a position that is within 1/4 of the short side length from the 2a side (50 mm from the light incident end face), c is a substantially intermediate position in the short side direction of the light guide plate 2 (100 mm from the light incident end face). It is a measurement result of the brightness | luminance.

  Even if the LEDs 8 are arranged on both sides in the vicinity of the joint A where the respective light guide plates overlap as in the comparative example 2, the brightness at the width D part of the joint A (a in FIGS. 19A and 19B). ) Was prominently high.

20 (a) and 20 (b) are emission surfaces when the LEDs 8 arranged on the side surface (incident end surface 2a) of the light guide plate 2 emit light and light enters the light guide plate 2 in Comparative Example 3. It is the measurement result of the brightness | luminance in the seam part A vicinity of the light radiate | emitted from the side (surface side of the light-guide plate 2 of Fig.18 (a), (b)). 20A and 20B, the horizontal axis represents the measurement range along the longitudinal direction of the light guide plate 2 including the vicinity of the joint A (the range of L1 to L2 in FIG. 18B), and the vertical axis represents It is luminance (cd / m ² ).

  20A shows a case where the width D (see FIG. 18A) of the joint portion A between the end surfaces (plane end portions 2d and 2e) of the adjacent light guide plates 2 is 10 mm. This is when the width D of the joint A is 5 mm. 20A and 20B, a is a measurement result of luminance at a position 6 mm inward slightly from the incident end face 2a side (LED8 side) of the light guide plate 2, and b is an incident end face of the light guide plate 2. As a result of measuring the luminance at a position that is within 1/4 of the short side length from 2a (50 mm from the light incident end face), c is a substantially intermediate position in the short side direction of the light guide plate 2 (100 mm from the light incident end face). It is a measurement result of luminance.

  When the LED 8 is arranged on the joint A as in Comparative Example 3, the brightness (a in FIGS. 20A and 20B) protrudes and becomes high in the width D part of the joint A, resulting in uneven brightness. Was very big.

  By the way, for example, the lower surface on the front end side along the longitudinal direction of the escalator 11 shown in FIG. 1 is provided with a seam portion (A in FIG. 1) bent at a predetermined angle. For this reason, it is necessary to arrange each adjacent light guide plate at a predetermined angle in the vicinity of the joint A.

  Therefore, in the present embodiment, for example, as shown in FIG. 21A, the light guide plate 2 on the other side (the right side in FIG. 21A) is the other side (the left side in FIG. 21A). The light guide plate 2 ′ is disposed at a predetermined angle θ (for example, 150 degrees), and is held and fixed so that the sloped end surface of the light guide plate 2 ′ is in contact with the sloped end surface of the light guide plate 2 ′. In FIG. 21 (a), the arrow L indicates the light emission direction from the light guide plates 2, 2 '. The angle direction of the light guide plate 2 ′ shown in FIG. 21A (the light guide plate on the left side of FIG. 21A) is guided at the bent seam A on the lower surface of the escalator 11 shown in FIG. The direction is opposite to the angle direction of the optical plate.

  Further, as shown in FIG. 21B, there is no LED (light source) in the vicinity of the side surface of the joint portion A between the end surfaces of the adjacent light guide plates 2 and 2 ′. The LEDs 8 are arranged at a predetermined interval on the side surface (incident end surface 2a) at a position slightly away from the end surface (joint portion A). In FIG.21 (b), distance d1 between LED8 arrange | positioned on the both sides with respect to the end surface (joint part A) of each adjacent light-guide plate 2, 2 'shall be 3 mm, and distance between each other LED8. Was set to 6.4 mm.

  As shown in FIGS. 22 (a) and 22 (b), the end surfaces (seam portions A) of the light guide plates 2 and 2 ′ arranged at a predetermined angle θ (for example, 150 degrees) are formed in a vertical plane shape. It may be. Even in this case, similarly, the distance d1 between the LED 8 disposed on both sides of the end faces (joint portion A) of the adjacent light guide plates 2, 2 ′ is 3 mm, and the distance between the other LEDs 8 is It is set to 6.4 mm.

FIG. 23 shows the emission surface side (FIG. 21 (b) when the LEDs 8 arranged on the side surfaces (incident end surface 2a) of the light guide plates 2 and 2 ′ emit light and light enters the light guide plates 2 and 2 ′. ) In the vicinity of the joint A of the light emitted from the light guide plate 2, 2 ′) (substantially the same measurement result in the case of FIGS. 22A and 22B). there were). Note that the horizontal axis of FIG. 22 is the measurement range along the longitudinal direction of the light guide plates 2 and 2 ′ including the vicinity of the joint A (the range of L1 to L2 in FIG. 21B), and the vertical axis is the luminance (cd / m ² ).

  In FIG. 23, a is a measurement result of luminance at a position 6 mm inward slightly from the incident end face 2a side (LED8 side) of the light guide plates 2 and 2 ′, and b is the incident end face 2a of the light guide plates 2 and 2 ′. The luminance measurement result at a position that is within 1/4 of the short side length from the light (50 mm from the light incident end face), c is a substantially intermediate position in the short side direction of the light guide plate 2, 2 ′ (100 mm from the light incident end face) It is a measurement result of the brightness at.

  As is apparent from the measurement results, the luminance unevenness along the joint direction in the vicinity of the joint portion A was small.

  Thus, for example, when a plurality of lighting devices 1 (or lighting devices 1a) are arranged along the longitudinal direction of the second escalator 11 (both sides of the lower surface 11a) shown in FIG. The adjacent end faces of each light guide plate 2 of the adjacent lighting device 1 (or lighting device 1a) are simply rectangular in the XZ cross section, and are provided with a gap of 1 to 2 mm at the joint between the end surfaces. When arranging the LEDs 8 at a predetermined interval on one side surface (incident end surface 2a) of the light plate 2, by not arranging the LED (light source) near the side surface of the joint portion A of each adjacent light guide plate 2, The luminance unevenness along the joint direction in the vicinity of the joint portion A can be reduced.

  Further, since the gap of the joint portion A is as small as 1 to 2 mm, a change in luminance between the joint A portion and the exit surface of the light guide plate 2 can be suppressed to a small value. Accordingly, the vicinity of the joint portion A of each adjacent light guide plate 2 can be illuminated so as to be inconspicuous, so that the appearance can be improved.

  Furthermore, since a gap d of 1 to 2 mm is provided in the joint portion A between the end surfaces of the adjacent light guide plates 2, the end surfaces of the light guide plates 2 are prevented from interfering with each other even if the light guide plate 2 is linearly expanded. can do.

  Moreover, since the said illuminating device 1 (illuminating device 1a) which concerns on this embodiment is an edge light system of the structure which provided the light emission unit 3 in the one side surface (or both side surface) of the light-guide plate 2, it is an illuminating device. The overall weight and thickness can be reduced. Therefore, in order to set it as a long illuminating device, the end surface of each light-guide plate 2 of the adjacent illuminating device 1 can be connected, and a lightweight and thin long illuminating device can be provided.

  In addition, in the said embodiment, although it was the example which applied the illuminating device 1 (or illuminating device 1a) to the illuminating device of an escalator, it is installed in an office, a factory, etc. besides this, without being limited to this. The present invention can be similarly applied to a long illumination device.

  Moreover, in the illuminating device of the said embodiment, although it was the structure which has arrange | positioned the light emission unit 3 (LED8) in one side surface (incident end surface 2a) along the X-axis direction of the light-guide plate 2, X-axis of the light-guide plate 2 is used. The present invention can be similarly applied to a configuration in which the light emitting units 3 (LEDs 8) are arranged on both side surfaces along the direction.

DESCRIPTION OF SYMBOLS 1, 1a Illuminating device 2, 2 'Light guide plate 2a Incident end surface 2b Bottom surface 2c Output surface 3 Light emitting unit 4 Reflecting sheet 5 Diffusion sheet 6 Concave (concave pattern)
7 Projections (projection pattern)
8 LED (Primary light source)
10 First escalator 11 Second escalator 11a Lower surface A Seam

Claims (6)

A primary light source is installed on at least one side surface of a light guide plate made of a resin material, and the light guide plate is emitted from an output surface, a bottom surface facing the output surface, and the primary light source provided on at least one side surface. An illumination device of an edge light system having an incident end face for entering light,
The primary light source is arranged in parallel to the X axis, with the normal line of the XY plane composed of the X axis and the Y axis orthogonal to the X axis as the Z axis, and the light guide plate is the XY plane. The incident end surface of the light guide plate is parallel to the XZ plane,
The light guide plate has a plurality of concave stripe patterns parallel to the X-axis direction formed at a predetermined pitch on the bottom surface and a plurality of convex stripe patterns parallel to the Y-axis direction formed at a predetermined pitch on the emission surface. And
The concave stripe pattern formed on the bottom surface of the light guide plate has a V-shaped cross section and an apex angle of 65 ° to 105 °,
When a plurality of the lighting devices are connected along the X-axis direction, the primary light source is not provided in the vicinity of the side surface of the light guide plate along the X-axis direction of the joint portion between the light guide plates of the adjacent lighting devices. The lighting device is characterized in that the primary light sources are installed at predetermined intervals on a side surface of the light guide plate along the X-axis direction that is a predetermined distance away from the joint portion. A primary light source is installed on at least one side surface of a light guide plate made of a resin material, and the light guide plate is emitted from an output surface, a bottom surface facing the output surface, and the primary light source provided on at least one side surface. An illumination device of an edge light system having an incident end face for entering light,
The primary light source is arranged in parallel to the X axis, with the normal line of the XY plane composed of the X axis and the Y axis orthogonal to the X axis as the Z axis, and the light guide plate is the XY plane. The incident end surface of the light guide plate is parallel to the XZ plane,
The light guide plate has a plurality of concave stripe patterns parallel to the X-axis direction formed at a predetermined pitch on the bottom surface and a plurality of convex stripe patterns parallel to the Y-axis direction formed at a predetermined pitch on the emission surface. And
The concave stripe pattern formed on the bottom surface of the light guide plate has a V-shaped cross section and an apex angle of 120 ° to 150 °,
When a plurality of the lighting devices are connected along the X-axis direction, the primary light source is not provided in the vicinity of the side surface of the light guide plate along the X-axis direction of the joint portion between the light guide plates of the adjacent lighting devices. The lighting device is characterized in that the primary light sources are installed at predetermined intervals on a side surface of the light guide plate along the X-axis direction that is a predetermined distance away from the joint portion.   3. The lighting device according to claim 1, wherein the convex stripe pattern formed on the light exit surface of the light guide plate has a trapezoidal shape, a lenticular lens shape, or a parabolic shape in cross section.   4. The light guide plate has a reflection sheet that reflects light on a bottom surface side, and a light diffusion plate that uniformly diffuses light on an output surface side of the light guide plate. The lighting device according to any one of the above.   4. The lighting device according to claim 1, further comprising a reflection sheet that reflects light on a bottom surface side of the light guide plate. 5.   The distance from the intermediate portion along the X-axis direction of the joint portion to the primary light source provided at the position closest to the joint side of the side surface of one of the adjacent light guide plates is 1 to 5 mm. The lighting device according to any one of claims 1 to 5.