JP2015011278A - Internal illumination type bulletin device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an internal illumination type bulletin device which can easily change light arrangement characteristic of the illumination device without luminance unevenness (deterioration of luminance uniformity) even the device size is increased.SOLUTION: Both end parts positioned on both sides of a width direction of a circuit board 21 of a light diffusion film 30 having size for covering an upper space of an LED array formed of plural LEDs 23, are held by a pair of movement inhibition tools 41 forming a film fitting structure 40, and in the state, are fitted to a substrate 5. At least one of the pair of movement inhibition tools 41, 41 is configured so as to change its position freely for changing distance to the LED group in a horizontal or a vertical direction.

Description

  The present invention relates to a hollow-type internally lit display device.

  Conventionally, as an internal lighting type display device used for a signboard, a sign, a traffic information board, etc., a fluorescent lamp type device in which a plurality of fluorescent lamps are arranged on the back side of the display plate has been used. However, electroluminescence (hereinafter referred to as EL), such as a light emitting diode (hereinafter referred to as LED), a thin film EL element (organic EL, inorganic EL), etc. has a long life and can reduce power consumption. With the progress of the light source, recently, an internal lighting type display device in which an EL light source is arranged has been mainly used. In particular, LEDs are widely used in internally illuminated display devices because of the variety of light sources and the price reduction in addition to the above-mentioned special choices.

  As an internal lighting type bulletin board device using LEDs or the like as a light source, a direct-type internal lighting type bulletin board device in which a plurality of LEDs or the like are arranged on the back side of the display plate, and a light guide plate arranged on the back side of the display plate. An edge-lighted internal lighting type display device in which a light source composed of a plurality of LED rows is arranged on the side surface, and a hollow type internal-lighting type display device in which a light guide plate is removed from the edge-lighted internal lighting type display device are known. It has been.

  Each of these three methods has its characteristics, and the method of use is selected according to its advantages and disadvantages. Directly-directed internal-illuminated bulletin board devices are often used for large-sized guide plates such as signboards and high-luminance signboards because they are easy to handle in size and easily adjust the amount of light. However, in the direct-lighting type internal bulletin board, when the thickness of the internal lighting type bulletin board is reduced, a see-through phenomenon in which a light source such as an LED can be seen through the display board and luminance unevenness are likely to occur. In particular, when a sufficient depth for installation cannot be secured, luminance unevenness tends to occur on the display panel. In addition, the large direct-lighting type internal bulletin board has a problem that the manufacturing cost and the running cost increase because of the large number of light sources. The edge-lit internal lighting type display device has an advantage that there is little luminance unevenness and it is easy to make the device thin because it uses a light guide plate. However, there is a problem in that the size of the light guide plate is limited, the light guide plate is relatively expensive, and in the case of a large-sized device, the light guide plate and the casing need strength reinforcement.

  On the other hand, the hollow-type internally-illuminated display device has a problem that unevenness in luminance is likely to occur and it is difficult to increase the luminance, as compared with the direct method and the edge light method, and it is difficult to increase the size. However, there is no need for an installation plate such as an LED or a diffusion plate compared to the direct type, and there are fewer light sources such as LEDs, and there is no need for a light guide plate compared to the edge light method, so manufacturing costs and running costs are low. Has good advantages. Further, there is an advantage that both display surfaces can be internally illuminated by a group of LEDs. For this reason, when replacing a conventional fluorescent lamp type internally illuminated display device such as a station guide plate having a height of 500 mm or less with an internally illuminated display device using LEDs or the like as a light source, a hollow with little unevenness in luminance is provided. There is a desire for an internally illuminated display device of the type.

  Japanese Patent Application Laid-Open No. 2011-180278 (Patent Document 1) adjusts the irradiation direction of light emitted from a linear light source by providing a light diffusion lens to a linear light source composed of a plurality of LEDs attached to a housing. Thus, there is disclosed a hollow-type internally-illuminated bulletin board device in which the display surface is irradiated with light uniformly so as not to cause uneven brightness by providing appropriate light distribution characteristics.

JP 2011-180278 A

  In the internally-illuminated bulletin board described in Patent Document 1, since the light condensed from the light source has an appropriate light distribution characteristic by the light diffusing lens, the uneven luminance of the display unit can be eliminated to some extent. However, in the structure disclosed in Patent Document 1, when the size of the internal lighting type display device is changed, in order to increase the luminance uniformity with the size, an illumination device (LED module) including a light source and a light diffusion lens is used. ) Need to be changed. Therefore, it is necessary to prepare an illuminating device for each size of the internally illuminated display device, and the manufacturing cost of the internally illuminated display device cannot be sufficiently reduced.

  An object of the present invention is to provide an internally-illuminated bulletin board with high luminance uniformity.

  Another object of the present invention is to provide an internally illuminated display device that can easily change the light distribution characteristics of a lighting device and can cope with a difference in the size of a housing.

  Still another object of the present invention is to provide an internally illuminated display device that has high luminance uniformity and can reduce the manufacturing cost and running cost.

  The internally-illuminated bulletin board according to the present invention includes a housing, a lighting device attached to a base body provided in the housing and housed in the housing, and light emitted from the lighting device provided in the housing is transmitted. And a display unit provided to do so. The illumination device of the present invention includes a light source, a light diffusion member, and a diffusion state changing unit. The light diffusing member is disposed with a space between the light source and diffuses light emitted from the light source. The diffusion state changing means changes the diffusion state of light emitted from the light source by changing the attachment state of the light diffusion member.

  In the internal illumination type bulletin board apparatus of the present invention, the diffusion state changing means for changing the diffusion state of the light by changing the attachment state of the light diffusion member is provided, so that the diffusion state of the light emitted from the light source can be changed as necessary. You can change the light distribution characteristics. That is, even when the shape of the casing and the shape and size of the display unit are changed, the luminance uniformity of the display unit can be easily increased only by changing the mounting state of the light diffusion member. Also, the average luminance is improved. As a result, according to the present invention, it is not necessary to prepare a dedicated lighting device every time the size of the internally illuminated display device is different, and the manufacturing cost of the internally illuminated display device can be reduced. Furthermore, since the light distribution characteristics can be changed by changing the type of the light source of the illuminating device and changing the mounting state of the light diffusing member by the diffusion state changing means, Even if it is an illuminating type | mold display apparatus, it can suppress that a brightness | luminance nonuniformity (namely, fall of brightness | luminance uniformity) generate | occur | produces.

  Note that in this specification, a housing is a structure having a space for housing a lighting device and provided with a display portion. This housing includes both a case where the display unit is integrally formed and a case where a separate display unit is attached to a mounted structure such as a frame structure. Moreover, although this housing | casing is provided with the wall part to which a base | substrate is attached, it cannot be overemphasized that this wall part may comprise a base | substrate.

  The specific diffusion state changing means can be constituted by, for example, a light diffusing member attachment structure for attaching the light diffusing member to the base. In this case, the light diffusing member mounting structure is configured to change the mounting position of the light diffusing member with respect to the base. When the mounting position of the light diffusing member with respect to the base is changed, the shape of the light diffusing member is changed. As a result, the light distribution characteristic of the light diffusing member changes based on the change in the shape of the light diffusing member, and the light diffusion from the light diffusing member also changes based on the change in the distance between the light diffusing member and the light source. appear. Therefore, by changing the mounting position of the light diffusing member with respect to the base, it is possible to easily change the diffusion state of the light emitted from the light source by causing a change in the light distribution characteristics and the diffusion state.

  The light diffusing member can be, for example, a flexible sheet-like light diffusing member. In this case, the light diffusing member mounting structure is configured to include a pair of movement blocking devices that are arranged so as to sandwich the light source therebetween and block the movement of the end portion of the sheet-like light diffusing member. And at least one of a pair of movement prevention tools is made into the structure which can change a position so that the distance between light sources may be changed. If comprised in this way, since a sheet-like light-diffusion member deform | transforms by the change of the distance of the movement prevention tool which can change a position, and a light source, the light distribution characteristic of a sheet-like light-diffusion member changes, and a sheet-like light-diffusion member and The distance to the light source can be easily changed. Of course, even when the position of the other of the pair of movement preventing tools is changed, the shape of the sheet-like light diffusing member can be changed. Therefore, when such a configuration is adopted, variations in the diffusion state that can be changed can be increased.

  Moreover, it is preferable that both of a pair of movement prevention tools have the structure which can change a position. If comprised in this way, the variation of the diffusion state which can be changed can be increased further.

  The light source can be, for example, a light emitting diode group (LED group) in which a plurality of light emitting diodes (LEDs) are arranged at intervals. In this case, the LED group preferably includes one or more LED rows arranged such that a plurality of LEDs form at least one row. In this case, the sheet-like light diffusing member is configured to have a rectangular shape when not deformed. Then, the sheet-like light diffusing member is attached so that the pair of opposing sides are prevented from moving by the pair of movement preventing tools in a state of being curved and deformed so as to protrude in the direction away from the base. If comprised in this way, a sheet-like light-diffusion member can be changed into a dome shape. Therefore, the distance between the sheet-like light diffusing member and the LED group in the direction in which the LED group emits light can be gradually changed using the distance between the apex of the dome as a reference distance. As a result, it is possible to diffuse light without unevenness around the sheet-like light diffusing member. In the dome-shaped sheet-shaped diffusion member, openings are formed at both ends in the direction in which the LED group extends. Since the display unit is configured so as not to be opposed to the opening in the housing, the presence of such an opening is not particularly problematic.

  An optical lens for controlling the diffusion and directivity of light emitted from the plurality of LEDs may be further provided between the plurality of LEDs and the light diffusion member. With this configuration, the light diffusibility can be changed both by selecting the optical lens and changing the shape of the light diffusing member. Therefore, it is difficult to respond by simply changing the mounting state of the light diffusing member. It is possible to cope with the shape and the shape and size of the display unit.

  When an optical lens is used, a plurality of LEDs can be fixed on a common circuit substrate, and the optical lens can be individually attached to the plurality of LEDs. And you may comprise as a module in which several LED, the circuit base | substrate, and the optical lens were integrated. If comprised in this way, an assembly of an internally-illuminated bulletin board will become easy.

It is a disassembled perspective view for demonstrating schematic structure of the guide plate of the double-sided display to which the internal illumination type | mold notice apparatus of this invention is applied. It is a longitudinal cross-sectional view which shows the specific internal structure of guide plate 1 '. It is a top view of the illuminating device and the base | substrate of the state which removed the light-diffusion film. It is a figure explaining the state which fixes the edge part of a diffusion film. It is a figure explaining the deformation | transformation of the light-diffusion film of the guide plate of this Embodiment. It is a figure which shows typically the relationship between an LED module and a diffusion film.

  Hereinafter, an example of an embodiment of a hollow-type internally-illuminated posting apparatus according to the present invention will be described in detail with reference to the drawings. FIG. 1 is an exploded perspective view for explaining a schematic configuration of a double-sided display guide plate 1 to which the internally illuminated display device of the present embodiment is applied. An embodiment having a specific structure is shown in FIG. Therefore, the structure of FIG. 1 and the structure shown in FIG.

  As shown in FIG. 1, the guide plate 1 includes a housing 3, a base 5, a display unit 7 including two display plates 7 </ b> A and 7 </ b> B provided in the housing 3, and a base 5. And an illuminating device 9 attached thereto. The housing 3 has a frame shape formed of a metal plate such as a steel plate, a stainless steel plate, or an aluminum alloy, and includes a substantially rectangular upper wall portion 3a and a pair of substantially rectangular side wall portions 3b and 3c. The upper wall 3a and the bottom wall 3d facing each other are formed. In the detailed structure shown in FIG. 2 and subsequent figures, the base 5 also serves as the bottom wall 3d, but may be the upper wall 3a, the side wall 3b, or 3c. The material of the housing 3 can be arbitrarily selected depending on the strength of the housing, the heat dissipation of the LED, the appearance, the cost, and the like.

  FIG. 2 is a longitudinal sectional view showing a specific internal structure of the guide plate 1 ′. In FIG. 2, hatching indicating a cross section is omitted. FIG. 3 is a plan view of the illumination device 9 and the substrate 5 with the light diffusion film removed. In the specific embodiment shown in FIG. 2, a pair of edge portions 3e and 3f to which the pair of side wall portions 3b and 3c of the upper wall portion 3a are not connected are extended toward the bottom wall portion 3d side. A pair of standing wall portions 13 and 15 extending along the portions 3e and 3f are formed, respectively. Groove portions 11A and 11B that open toward the bottom wall portion 3d are formed in the pair of standing wall portions 13 and 15. The grooves 11A and 11B have a length extending along the edges 3e and 3f. Similarly, a pair of edge portions 5a and 5b to which the pair of side wall portions 3b and 3c of the base 5 constituting the bottom wall portion 3d is not connected extend toward the upper wall portion 3a and the edge portions 5a and 5b. A pair of upright wall portions 13 ′ and 15 ′ extending along the line are formed. Grooves 11′A and 11′B that open toward the upper wall 3a are formed in the pair of upright walls 13 ′ and 15 ′. The groove portions 11′A and 11′B have a length extending along the edge portions 5a and 5b. The depths of the groove portions 11A and 11B and the groove portions 11′A and 11′B are determined by inserting the upper end portions of the display plates 7A and 7B into the groove portions 11A and 11B, and then setting the lower end portions of the display plates 7A and 7B to the groove portion 11 It is determined to have dimensions allowing insertion into 'A and 11'B.

  In addition, in order to use the light from an illuminating device effectively, it is desirable to stick a reflective sheet on the inner surface side of the housing.

  The two display plates 7A and 7B constituting the display unit are formed of a light-transmitting material such as acrylic or polycarbonate. In the present embodiment, the display boards 7A and 7B have milky white color for diffusing light. Characters, symbols, designs, and the like are printed on the surfaces of the display boards 7A and 7B to form guide boards. In addition, you may stick the sheet | seat which printed the character, the symbol, the design, etc. on the surface of the display boards 7A and 7B.

  The base 5 constituting the bottom wall portion 3d of the housing 3 is formed of a metal plate such as a steel plate, a stainless steel plate, or an aluminum alloy, like the other wall portions constituting the housing 3. An illuminating device 9 is provided on the surface facing the upper wall portion 3a of the base 5.

  The illuminating device 9 has the LED module 20, the light diffusion film 30 which comprises a sheet-like light-diffusion member, and the film attachment structure 40 which comprises a light-diffusion member attachment structure. The LED module 20 includes a circuit board 21 formed in a substantially rectangular shape, a plurality of LEDs 23 mounted on the surface of the circuit board 21 so as to form a row at intervals in the longitudinal direction of the circuit board 21, and a plurality of LEDs 23 And a plurality of optical lenses 25 provided respectively. In the present embodiment, a commercially available LED unit called a lens-equipped LED is used. In order to obtain a necessary amount of light, a plurality of LED elements may be accommodated in one LED unit. On the circuit board 21, a power supply circuit pattern (not shown) to which power is supplied from a power supply unit (not shown) is formed. Since the detailed configuration of the power supply unit is not related to the gist of the present invention, the description thereof is omitted. The power supply circuit pattern on the circuit board 21 is configured so that a DC voltage can be applied to each of the plurality of LEDs 23. In the present embodiment, the circuit board 21 is fixed to the base body 5 using a double-sided taping member so that the plurality of LEDs 23 face the upper wall portion 3a. The circuit board 21 may be fixed to the base body 5 with other fastening members such as screws. In the present embodiment, the LEDs 23 are arranged on the circuit board 21 at intervals of 50 mm to configure the LED group. In the present embodiment, one LED row is used, but it goes without saying that the LED group may be constituted by a plurality of LED rows. The optical lens 25 has a function of controlling the diffusion and directivity of light emitted from the LED 23.

  The light diffusing film 30 is formed into a sheet shape from a flexible polymer material having light diffusibility, and the shape when not deformed is rectangular. As the light diffusion film 30 of the present embodiment, for example, PET nano buckling NB-AD3303-100 manufactured and sold by Oji Paper Co., Ltd. (thickness 90 μm, total light transmittance 91%, diffusion angle 33 ° / 3 °) ) Can be used. The light diffusion film 30 has a size that completely covers the upper space of the LED array composed of the plurality of LEDs 23. The light diffusing film 30 is attached to the base 5 in a state where both end portions located on both sides in the width direction of the circuit board 21 are held by two movement blocking devices 41 constituting the film attachment structure 40. The light diffusion film 30 is bent between the plurality of LEDs 23 in a state of being bent and deformed in a dome shape so as to protrude in a direction away from the base body 5 with both ends held by the two movement blocking devices 41. They are arranged at intervals. In this configuration, the distance between the sheet-like light diffusing member and the LED group in the direction in which the LED group emits light can be gradually changed using the distance between the apex of the dome as a reference distance, It is also possible to gradually change the distance between the movement inhibitor and the movement blocking tool as a reference distance. . As a result, it is possible to diffuse light without any unevenness around the light diffusion film 30. When the dome-shaped light diffusion film 30 is used, openings are formed at both ends in the direction in which the LED group extends. However, in the present embodiment, since these openings do not face the display panels 7A and 7B, there is no particular problem. As shown in FIG. 4, a plurality of through holes 31 are formed in the pair of end portions held by the pair of movement blocking devices 41 of the light diffusion film 30 with a predetermined interval in the direction in which the LED row extends. Yes.

  Each of the pair of movement blocking devices 41 includes an elongated angle 43 having an L-shaped cross section in a direction orthogonal to the longitudinal direction. As shown in FIG. 4, a plurality of through holes 45 are formed in the first wall portion 43 </ b> A extending in the vertical direction of the angle 43 at a predetermined interval in the longitudinal direction. A bolt (not shown) is inserted into the plurality of through holes 45 in a state in which the plurality of through holes 31 formed at the end of the light diffusion film 30 are aligned, and a nut (not shown) is screwed into the bolts. The light diffusion film 30 is fixed to the first wall 43A of the angle 43. A through hole 31 and a through hole 45 are formed at both ends in the longitudinal direction of the light diffusion film 30 and the first wall portion 43A of the angle 43, and a through hole is formed at the same position as the first wall portion 43A of the angle 43. A formed pressing plate having substantially the same length may be prepared, and a light diffusion film may be attached between the angle and the pressing plate with a bolt and a nut. Alternatively, the light diffusion film 30 may be attached to the first wall 43A with an adhesive or the like without forming the through holes 31 and the through holes 45 in the light diffusion film 30 and the first wall 43A of the angle 43.

  As shown in FIGS. 3 and 4, the second wall 43 </ b> B extending in the horizontal direction of the angle 43 is formed with through holes 47 at both ends in the longitudinal direction.

  As shown in FIG. 4, the angle 43 is slidable in the width direction of the circuit board 21 with respect to the base body 5 by the mounting structure 50 using the through holes 47 provided at both ends of the second wall portion 43 </ b> B. Fixed. A mounting structure 50 provided for one through-hole 47 shown in FIG. 4 includes a bolt member 53 fitted to a guide rail 51 fixed to the base 5 so as to be orthogonal to the angle 43, and a second of the angle 43. Two nuts 55 and 57 that are screwed into the threaded portion of the bolt member 53 that passes through the through-hole 47 formed in the wall portion 43B. The guide rail 51 is formed of a steel plate, a stainless steel plate, an aluminum alloy plate, or the like, and is fixed to the base body 5 by welding or the like, and a pair of upright walls standing from both ends of the bottom wall portion 51 in the width direction. Parts 51B and 51C. The tip portions of the pair of standing wall portions 51B and 51C are folded inward to form a pair of spring portions 51D and 51E. The pair of spring portions 51 </ b> D and 51 </ b> E are formed continuously in the longitudinal direction of the guide rail 51. The bolt member 53 is integrally provided with a seat portion 53A that slides on the bottom wall portion 51A of the guide rail 51 on the base 5 side. The seat portion 53A has a thickness that is slightly larger than a gap (hereinafter referred to as a “main gap”) between the tip end portions of the pair of spring portions 51D and 51E of the guide rail 51 and the bottom wall portion 51A. When the seat 53A of the bolt member 53 is pushed into the gap, the gap is widened, and the seat 53A is fixed to the guard rail 51 by the reaction force. The magnitude of the reaction force is determined by the difference between the thickness of the seat portion 53A and the gap, the material of the guide rail, and the like, and becomes a force for fixing the bolt member 53. However, it is preferable to set the magnitude of the reaction force to such an extent that the bolt member 53 can be slid on the guide rail 51 by human power. Next, the nut 55 is screwed into the bolt member 53, the through hole 47 of the second wall portion 43 </ b> B of the angle 43 is inserted into the bolt member 53, and the nut 57 is further screwed to fix the angle 43.

  By setting it as such a structure, adjustment of the distance of a light-diffusion film and LED can be performed with the following two methods. In the first method, the position of the angle 43 can be moved closer to or away from the illumination device 9 by sliding the bolt member seat 53A in the longitudinal direction of the guide rail 51 to adjust the position. The second method is to adjust the longitudinal position of the bolt member 53 of the nut 55 and the nut 57 to change the height of the angle 43 so as to bring the distance between the light diffusion film and the LED closer to or away from each other. be able to. When the mounting structure 50 is used, the height of the angle 43 can be changed by tightening and releasing the nut 55 and the nut 57, and the light diffusion film can be moved closer to or away from the lighting device 9. In addition, by sliding the bolt member 53 on the guide rail 51, the horizontal position of the angle 43 can be moved closer to or away from the lighting device 9. When moving one angle 43, the bolt members 53 of the two mounting structures 50 provided at both ends of the angle 43 in the longitudinal direction are operated.

  If the position of at least one of the pair of movement blocking devices 41, 41 is changed so as to change the horizontal and vertical distances between the LED groups as in the present embodiment, the light diffusion film 30 is deformed. The light distribution characteristics of the light diffusion film 30 can be changed, and the distance between the light diffusion film 30 and the LED group can be easily changed. Therefore, when such a configuration is adopted, variations in the diffusion state that can be changed can be increased. In addition, as shown in FIG. 5, if the structure which changes both the fixed positions of a pair of movement prevention tools 41 and 41 is employ | adopted, the variation of the diffusion state which can be changed can be increased further.

  Next, in order to confirm the effect of the present invention, examples and comparative examples of a hollow-type internally-illuminated bulletin board manufactured according to the present embodiment will be described. In addition, this invention is not restrict | limited to the following Example.

[Components of Examples and Comparative Examples]
Details of the constituent members used in the examples and comparative examples are as follows.

-LED with lens: LED “TYGA-350-300” with a lens manufactured by First System Co., Ltd. (width dimension: 37.5 mm)
LED device: LED device “NESW157B” manufactured by Nichia Corporation (width 3 mm)
・ Light diffusion film: “Nano Buckling” manufactured by Oji Paper Co., Ltd.
-Display board: Milky white acrylic board (thickness 5mm)
[Measurement method of illuminance of guide plate]
About the produced guide board, the illumination intensity of the display board surface was measured by Konica Minolta Co., Ltd. CL-200A in the state which light-emitted LED. The measurement of illuminance was performed at 50 mm intervals in the height direction with respect to the base at the center in the length direction of the display unit, and the illuminance uniformity and average illuminance were calculated.

  In addition, when noting the brightness of a light-emitting body, it is common to use a brightness | luminance. However, in this measurement, the measurement site is on the surface of the display board. In such a case, the luminance and the illuminance are in a one-to-one relationship, so measurement was performed with an illuminometer.

<Example 1>
A guide plate having a height dimension of 500 mm, a width dimension of 150 mm, and a length dimension of 900 mm from the base to the upper wall is prepared, and an LED with a lens is provided at the center in the width direction of the base 5 along the longitudinal direction of the base 5. Arranged. As schematically shown in FIG. 6, this lens-equipped LED was covered in a dome shape with a diffusion film having a width of 100 mm and a length of 900 mm. The light diffusion film was attached at a position where the distance from the lens-equipped LED was 20 mm. A reflective sheet was attached to the inner wall of the upper wall. A milky white acrylic plate was attached as a display part.

<Example 2>
The specifications were the same as those of the guide plate of Example 1 except that the light diffusion film was attached to the lens-equipped LED without leaving a gap.

<Comparative Example 1>
The specifications were the same as those of the guide plate of Example 1 except that the light diffusion film was removed.

The measurement results and calculation results of Examples 1 and 2 and Comparative Example 1 are shown in Table 1. In the table, “measurement position” is the distance in the height direction from the substrate, “average illuminance” is the average value of illuminance at each measurement position, and “uniformity” is the minimum value of illuminance as the maximum value of illuminance. It is a value obtained by multiplying the divided number by 100.

  As shown in Table 1, in Example 1 and Example 2 in which the LED with lens was covered with a light diffusing film in a dome shape, the average illuminance was 84 lx or more in comparison with Comparative Example 1 in which the light diffusing film was not used. Improved by up to 8%.

<Examples 3 to 4 and Comparative Example 2>
Except that the height from the base to the upper wall was changed to 350 mm, the guide plate had the same specifications as in Examples 1 and 2 and Comparative Example 1, and the same measurement as in Examples 1 and 2 and Comparative Example 1 Calculated.

  As shown in Table 2, in Example 3 and Example 4 in which the LED with lens was covered with a diffusing film in a dome shape, the average illuminance was 45 lx or more and the uniformity was higher than that in Comparative Example 2 in which no light diffusing film was used. Improved by up to 20%.

<Examples 5 to 6 and Comparative Example 3>
Except changing the width dimension of the guide plate to 200 mm, the guide plate has the same specifications as those of Examples 1 and 2 and Comparative Example 1, and the same measurements and calculations as in Examples 1 and 2 and Comparative Example 1 were performed.

  As shown in Table 3, in Example 5 and Example 6 in which the LED with lens was covered with a diffusing film in a dome shape, the average illuminance was improved by 132 lx or more compared to Comparative Example 3 in which no light diffusing film was used, The uniformity is improved by up to 20%.

<Examples 7 to 8 and Comparative Example 4>
Except that the height from the base to the upper wall was changed to 350 mm, the guide plate had the same specifications as in Examples 5 to 6 and Comparative Example 3, and the same measurements as in Examples 5 to 6 and Comparative Example 3 Calculated.

  As shown in Table 4, in Example 7 and Example 8 in which the LED with lens was covered with a diffusing film in a dome shape, the average illuminance was 92 lx or more and the uniformity was higher than that in Comparative Example 4 in which no light diffusing film was used. Up to 4% improvement.

  As described above, as can be seen from Tables 1 to 4, by attaching the light diffusion film of the present invention to the LED with a lens, in addition to the width 200 × height 350 in which the uniformity exceeded 70% even without the light diffusion film. A uniformity of 70% or more was obtained even with a width of 200 × height of 500 and a width of 150 × height of 350. Moreover, the average illuminance was improved in all sizes.

  Next, it experimented by changing LED with a lens into the LED device.

<Example 9>
A guide plate having a height dimension of 500 mm, a width dimension of 150 mm, and a length dimension of 900 mm from the base to the upper wall is prepared, and an LED device is arranged along the longitudinal direction of the base 5 in the center of the width of the base 5 did. As schematically shown in FIG. 6, this LED device was covered in a dome shape with a diffusion film having a width of 30 mm and a length of 900 mm. The light diffusion film was attached at a position where the distance from the LED device was 20 mm. A reflective sheet was attached to the inner wall of the upper wall. A milky white acrylic plate was attached as a display part.

<Example 10>
The specifications were the same as those of the guide plate of Example 9, except that the light diffusing film was attached to the LED device without any gap.

<Comparative Example 5>
The specifications were the same as those of the guide plate of Example 9 except that the light diffusion film was removed.

Table 5 shows the measurement results and calculation results of Examples 9 to 10 and Comparative Example 5.

  As shown in Table 5, in Example 9 and Example 10 in which the LED device was covered with a light diffusion film in a dome shape, the uniformity was improved by up to 15% compared to Comparative Example 5 in which no light diffusion film was used. .

<Examples 11 to 12 and Comparative Example 6>
The guide plate has the same specifications as those in Examples 9 to 10 and Comparative Example 5 except that the height dimension from the base to the upper wall is changed to 350 mm, and the same measurement as in Examples 9 to 10 and Comparative Example 5 Calculated.

  As shown in Table 6, in Example 11 and Example 12 in which the LED device was covered with a light diffusion film in a dome shape, the uniformity was improved by up to 22% compared to Comparative Example 6 in which no light diffusion film was used. .

<Examples 13 to 14 and Comparative Example 7>
Except that the width of the guide plate was changed to 200 mm, the guide plate had the same specifications as those of Examples 9 to 10 and Comparative Example 5, and the same measurements and calculations as in Examples 9 to 10 and Comparative Example 5 were performed.

  As shown in Table 7, in Example 13 and Example 14 in which the LED device was covered with a diffusion film in a dome shape, the uniformity was improved by up to 20% compared to Comparative Example 7 in which no light diffusion film was used.

<Examples 15 to 16 and Comparative Example 8>
A guide plate having the same specifications as those of Examples 13 to 14 and Comparative Example 7 except that the height dimension from the base to the upper wall portion was changed to 350 mm, and the same measurement as in Examples 13 to 14 and Comparative Example 7 Calculated.

  As shown in Table 8, in Example 15 and Example 16 in which the LED device was covered with a light diffusion film in a dome shape, the uniformity was improved by up to 27% compared to Comparative Example 8 in which no light diffusion film was used. .

  As can be seen from Tables 5 to 8, even in the LED device, the uniformity is improved by using the light diffusing film regardless of the size of the guide plate. If the guide plate size is appropriately selected, the uniformity can be increased to 70% or more. .

  In this example, the setting conditions of the light diffusing film that covers the LED and LED device with a lens in a dome shape were not changed, but the setting conditions were changed by changing the position of the movement blocking tool and the size of the light diffusing film. If the conditions are optimal, the uniformity can be improved and the average illuminance can also be improved.

  In the description of the above embodiment, the double-sided light emitting type internal bulletin board has been described. However, it is needless to say that the present invention may be applied to a single-sided light emitting type internal lighting type bulletin board having one surface as a reflection surface.

  In the description of the above embodiment, the example using the LED module having the bottom wall portion as the base has been described, but it is needless to say that the LED module may be provided using the top wall portion as the base.

  In the description of the above embodiment, both the pair of movement blocking devices 41 have a structure capable of changing the position, but only one movement blocking device 41 may have a structure capable of changing the position.

  Furthermore, in the above-described embodiment, the base body constitutes a part of the casing, but it is needless to say that the base body does not necessarily constitute a part of the casing.

  Moreover, although the light-diffusion member was comprised from the light-diffusion film, it is good also as a plate-shaped light-diffusion member with resin etc. In this case, both ends of the plate-like light diffusing member may be attached to the movement preventing tool with a deformable connector.

  Furthermore, it goes without saying that an optical lens such as a linear Fresnel lens for controlling the diffusion and directivity of light emitted from the plurality of LEDs may be provided between the plurality of light emitting diodes and the light diffusion member.

  Furthermore, it goes without saying that a light source such as a cold cathode tube or a thin film EL element can be applied instead of the LED group.

  According to the present invention, since the diffusion state of the light emitted from the LED group can be changed, the brightness uniformity of the internally illuminated display device can be increased as compared with the conventional case. In addition, since the light distribution characteristics can be changed by the diffusion state changing means, it is not necessary to prepare a lighting device for each size of the internally illuminated display device, and the manufacturing cost of the internally illuminated display device can be sufficiently reduced. it can. Furthermore, since the light distribution characteristics can be changed by changing the type of LED of the lighting device and the diffusion state changing means, even in an internally-illuminated display device having a larger size than before, luminance unevenness (brightness uniformity) Can be prevented from occurring.

DESCRIPTION OF SYMBOLS 1 Guide plate 3 Housing | casing 3a Upper wall part 3b, 3c Side wall part 3d Bottom wall part 3e, 3f Edge part 5 Base | substrate 5a, 5b Edge part 7A, 7B Display board 9 Illuminating device 11 Groove part 13 Standing wall part 15 Standing wall part 20 LED module 21 Circuit board 23 Light emitting diode 25 Optical lens 30 Light diffusing film 31 Through hole 40 Film mounting structure 41 Movement prevention tool 43 Angle 43A First wall portion 43B Second wall portion 45 Through hole 47 Through hole 50 Mounting structure 51 Guide rail 51A Bottom wall portion 51B, 51C Standing wall portion 51D, 51E Spring portion 53 Bolt member 53A Seat portion 55, 57 Nut

Claims (8)

A housing, a lighting device attached to a base body provided in the housing and housed in the housing, and a display provided in the housing so as to transmit light emitted from the lighting device An internally illuminated display device having a
The lighting device includes a light source,
A light diffusing member arranged to be spaced from the light source and diffusing light emitted from the light source;
An internally illuminated posting apparatus comprising: a diffusion state changing unit that changes a diffusion state of light emitted from the light source by changing a mounting state of the light diffusion member. The diffusion state changing means comprises a light diffusion member attachment structure for attaching the light diffusion member to the base,
2. The internally illuminated posting apparatus according to claim 1, wherein the light diffusing member mounting structure is configured such that a mounting position of the light diffusing member with respect to the base is changeable. The light diffusing member is composed of a flexible sheet-like light diffusing member,
The light diffusing member mounting structure includes a pair of movement preventing tools that are arranged so as to sandwich the light source therebetween and prevent movement of an end portion of the sheet-like light diffusing member,
The internally illuminated posting apparatus according to claim 2, wherein at least one of the pair of movement preventing tools has a structure that can be repositioned so as to change a distance between the light source.   The internally illuminated posting apparatus according to claim 3, wherein both of the pair of movement blocking tools have a structure whose position can be changed.   5. The internally illuminated display device according to claim 1, wherein the light source is a light emitting diode group in which a plurality of light emitting diodes are arranged at intervals. 6. The light source is a light emitting diode group in which a plurality of light emitting diodes are arranged at intervals.
The light emitting diode group includes one or more light emitting diode rows arranged such that the plurality of light emitting diodes form at least one row,
The sheet-like light diffusing member has a rectangular shape when not deformed, and in a state where the sheet-like light diffusing member is curved and deformed so as to protrude in a direction away from the base, a pair of opposing sides is formed by the pair of movement blocking tools. The internally illuminated display device according to claim 3, wherein movement is prevented.   The internal illumination according to claim 5 or 6, further comprising an optical lens for controlling diffusion and directivity of light emitted from the plurality of light emitting diodes between the plurality of light emitting diodes and the light diffusion member. Type posting device.   The plurality of light emitting diodes are fixed on a common circuit substrate, and the optical lens is individually attached to the plurality of light emitting diodes, and these are integrated into a module. Illuminated display device.

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