JP4326888B2 - Illumination device - Google Patents

Description

The present invention relates to an illuminating device that can ensure a wide light emitting surface, and more particularly to an illuminating device that can be mounted on a small device .

  In portable electronic devices, etc., an operation button or a surface light emitter formed of a light guide and a light source is provided on the back side of the liquid crystal display panel so that the operation button emits light or illuminates the liquid crystal display panel. There is.

  In the planar light emitting device shown in the following Patent Document 1, light sources are respectively provided adjacent to both sides of a plate-like light guide plate. Each light source is a fluorescent tube, and is arranged along the edge of the light guide plate. The light emitted from each light source is incident on the plate-shaped light guide plate, and the light is emitted to the illumination side of the plate-shaped light guide plate. Reflects at right angles.

Also, in the following Patent Document 2, a rod-shaped light guide is provided on the side surface of the plate-shaped light guide, and light from a light source is incident from an end surface of the rod-shaped light guide. The light introduced into the rod-shaped light guide is reflected toward the plate-shaped light guide by the reflecting surface provided on the side surface of the rod-shaped light guide, and the light incident on the plate-shaped light guide is vertical. The liquid crystal display unit that is reflected on the plate-like light guide and provided on the plate-like light guide is illuminated.
JP-A-5-203947 JP 2003-162915 A

  However, in the above-mentioned Patent Document 1, the light sources provided on both sides of the plate-shaped light guide plate are elongated and protrude from the side of the plate-shaped light guide plate, so that they are mounted on small devices. When this is done, the area facing the illumination side of the fluorescent tube becomes a non-light emitting area, resulting in useless space. Further, since a light source such as a fluorescent tube consumes a large amount of power, for example, when it is mounted on a portable electronic device, the battery driving time is shortened.

  The thing shown in patent document 2 aims at low power consumption using LED for a light source. However, since the light incident on the rod-shaped light guide is reflected to the plate-shaped light guide by the reflecting surface provided on the side surface of the rod-shaped light guide, the peripheral portion of the liquid crystal display panel is separated from the plate-shaped light guide. It must be arranged so that it does not protrude, that is, the peripheral edge does not overlap the rod-shaped light guide.

  Some combinations of a plate-like light guide and a rod-like light guide cover the rod-like light guide with a metal case in order to connect the plate-like light guide and the rod-like light guide. In this case, the area covered with the case is a non-light emitting area, and the outer frame is positioned in the case of a liquid crystal display panel, and the width dimension of the outer frame needs to be set large.

  Further, in the case of introducing light into the plate-shaped light guide through the rod-shaped light guide, it is necessary to introduce light from the light source to the entire edge of the plate-shaped light guide along which the rod-shaped light guide is aligned. It is necessary to set the length of the rod-shaped light guide to be equal to or greater than the width of the plate-shaped light guide.

The present invention solves the above-described conventional problems, can be mounted on a small device, can reduce the formation of a non-light emitting area outside the light emitting surface, and can reduce the installation space. An object of the present invention is to provide an illumination device capable of increasing the degree of freedom in design.

Illumination device of the present invention, the surface is light-emitting surface, the first light guide body and the first light guide body main reflection surface that reflects light toward the light emitting surface to the bottom surface is provided Y A second light guide whose width dimension in the X direction perpendicular to the Y direction is shorter than the width dimension in the X direction of the first light guide, and adjacent to the side surface extending in the direction ; and a light source which light is incident from an end face facing in the Y direction of the optical member to the inside of the second light guide body,
The surface of the second light guide is a light emitting surface, and the light from the light source is guided to the side surface extending in the Y direction on the opposite side of the surface adjacent to the first light guide. the first reflecting surface is provided for reflecting the body, a second reflecting surface for reflecting light from the light source toward the light emitting surface of the second light guide body have been found on the bottom surface ,
A plurality of operation buttons that are each illuminated with light from the light source are provided on the operation unit disposed on the front side of the first light guide and the second light guide, and the operation buttons are a region facing the light emitting surface of the first light guide member, and is characterized in that it is located in both areas of the region opposed to the light emitting surface of the second light guide body.

Moreover, the illumination device of the present invention includes a first light guide having a light emitting surface on the surface, and a main reflection surface that reflects light toward the light emitting surface on a bottom surface, and the first light guide. Adjacent to the side surface extending in the Y direction, a second light guide whose width in the X direction perpendicular to the Y direction is shorter than the width in the X direction of the first light guide, and the second A light source for allowing light to be incident on the inside of the second light guide from an end surface facing the Y direction of the light guide,
The surface of the second light guide is a light emitting surface, and the light from the light source is guided to the side surface extending in the Y direction on the opposite side of the surface adjacent to the first light guide. A first reflecting surface that reflects toward the body is provided, and a second reflecting surface that reflects light from the light source toward the light emitting surface of the second light guide is provided on the bottom surface;
A display panel that transmits light is provided on the front side of the first light guide and the second light guide, and the display panel faces the light emitting surface of the first light guide. It arrange | positions over the area | region of both the area | region and the area | region facing the said light emission surface of a said 2nd light guide.

In the illumination device of the present invention , the entire surfaces of the first light guide and the second light guide can emit light, so that even when mounted on a small device, a useless space is formed by a non-light emitting region. Can be reduced.

  In addition, the length of the second light guide is shorter than the width of the first light guide adjacent to the second light guide, and the second light guide and It is preferable that the light source is disposed so as not to protrude from both ends in the width direction of the first light guide.

  In this case, it is preferable that the first reflecting surface is provided with emitting means for radially spreading light into the first light guide.

  Thereby, a 2nd light guide and a light source do not protrude from the both ends of a 1st light guide, and the freedom degree of design can be raised.

  In addition, it is preferable that at least a connection portion between the first light guide and the second light guide is connected by an adhesive film having transparency or light diffusibility.

The first light guide and the second light guide may be connected in a state of being housed in a case having a predetermined shape.
The light source is preferably a light emitting diode.

  In the present invention, since the entire surfaces of the first and second light guides facing the illumination side can emit light, the non-light-emitting region can be set small, and the degree of design freedom can be increased. Therefore, even if it is mounted on a small device, a useless space is not formed largely. When mounted on a small display panel, the width of the outer frame provided on the display panel can be reduced.

  FIG. 1 is a plan view of the surface light emitter according to the first embodiment of the present invention when viewed from the illumination side, FIG. 2 is a view taken in the direction of the arrow 2 in FIG. 1, and FIG. . In the present embodiment, the illustrated Z1 direction is the illumination side.

  As shown in FIG. 1, the surface light emitter 1 </ b> A includes a first light guide 10, a second light guide 11, and a light source 12.

  The said 1st light guide 10 is a plate shape from which an XY planar view becomes a rectangle. The first light guide 10 is formed of a transparent member such as acrylic resin, polycarbonate resin, or glass. Further, as shown in FIG. 2, a main reflection surface 10a is formed on the bottom surface of the first light guide 10, and the main reflection surface 10a is cut into a triangular prism shape along the Y direction. It is a shape formed in parallel with the direction.

  The second light guide 11 is formed of the same transparent member as the first light guide 10, and the shape thereof is a rod shape (square column shape) extending in the Y direction (longitudinal direction). The length of the second light guide 11 is substantially the same as the width of the first light guide 10 in the Y direction. In addition, as shown in FIG. 1, a first reflecting surface in which a plurality of notches formed in a triangular prism shape in the Z direction are formed in parallel in the Y direction on the side surface on the X2 side of the second light guide 11. 11a is formed. Further, as shown in FIG. 3, the second light guide 11 has a bottom surface (a surface on the Z2 side) in which a plurality of notches that are notched in a triangular prism shape in the X direction are arranged in parallel in the Y direction. Two reflecting surfaces 11b are formed.

  The light source 12 is provided at the end of the second light guide 11 on the Y2 side. The light source 12 is small and has low power consumption, for example, a light emitting diode 12a. Although not shown, a reflecting plate is provided around the diode 12a on the side opposite to the second light guide 11, that is, on the Y2 side shown in FIG. 1, and emitted from the diode 12a toward the Y2 side. Control may be performed so that the reversely directed light is reflected to the second light guide 11 side.

  As shown in FIG. 2, the first reflective surface 11 a and the second reflective surface 11 b provided on the second light guide 11 have white reflective sheets 13 a and 13 b formed in a strip shape covering the uneven surface. 13b is provided in an overlapping manner. Similarly, a white reflective sheet 14 is also provided on the main reflective surface 10a of the first light guide 10 in an overlapping manner. Thereby, when the light from the light source 12 reaches the first reflecting surface 11a and the second reflecting surface 11b and the light is reflected to the opposite side to the first light guide 10, the X1 side And Z1 can be reflected respectively. In addition, illustration of the said reflective sheet is abbreviate | omitted in FIG. 1 and FIG.

  In place of the reflection sheets 13a, 13b, 14, a reflection layer made of white paint is printed along the uneven surfaces of the first reflection surface 11a, the second reflection surface 11b, and the main reflection surface 10a. It may be formed. Moreover, a mirror surface may be sufficient.

  As a method of joining the first light guide body 10 and the second light guide body 11, as shown in FIG. 1, along the connection portion S between the first light guide body 10 and the second light guide body 11. A transparent adhesive film 15 is provided. The transparent adhesive film 15 is formed in a belt shape with, for example, polyethylene terephthalate, polypropylene, polyethylene or the like. However, the transparent adhesive film 15 is not limited to the shape along the connection portion S as shown in FIG. 1, but on the illumination side of the first light guide body 10 and the second light guide body 11. It may be provided on the entire surface facing and joined. Moreover, in order to relieve the bright line emitted in the joining part S, you may use a light-diffusion adhesive film instead of a transparent adhesive film.

  As another bonding method, there is a method of providing a case 16 having an opening 16a on the illumination side around the first light guide 10 and the second light guide 11, as shown in FIG. The case 16 is made of synthetic resin or metal, and has a shape in which the inner surface of the case 16 and the first light guide body 10, the second light guide body 11, and the light source 12 are positioned without gaps. At this time, the connection portion S that is the boundary between the first light guide 10 and the second light guide 11 is formed so as to be in close contact. In addition, as another joining method, the method of adhering and fixing the 1st light guide 10 and the 2nd light guide 11 is mentioned, for example. In this case, the light emitted from the second light guide 11 can be effectively incident on the first light guide 10, so that the first and second light guides 10 and 11 are partially bonded. It is preferable to do.

  In the surface light emitter 1A formed as described above, when the diode 12a of the light source 12 emits light, the light from the diode 12a travels toward the second light guide 11. As shown in FIG. 1, the first reflection surface 11 a is reflected toward the first light guide 10, and the light spreads over the entire first light guide 10. The light hitting the main reflecting surface 10a is reflected on the Z1 side which is the illumination side.

  Further, in the present embodiment, the light incident on the second light guide 11 from the light source 12 is illuminated on the Z1 side as shown in FIGS. 2 and 3 by the second reflecting surface 11b. Reflected towards.

  Therefore, in the surface light emitter 1A of the present embodiment, the flat surface 10t facing the Z1 side of the first light guide 10 from which the light H1 (see FIG. 2) reflected by the main reflection surface 10a is emitted, and the first The plane 11t facing the Z1 side of the second light guide 11 from which the light H2 reflected by the second reflecting surface 11b (see FIGS. 2 and 3) is emitted functions as an effective light emitting surface. Therefore, in the conventional device, the surface of the second light guide 11 facing the illumination side is a non-light emitting region, and the second light guide 11 can function as a light emitting surface. Therefore, the non-light-emitting surface is only the area of the light source 12, and the formation of useless space can be reduced.

FIG. 4 is a plan view showing a surface light emitter according to a second embodiment of the present invention.
In the surface light emitter 1B, a bar-shaped second light guide 17 extending in the Y direction is provided adjacent to an edge of the first light guide 10 on the X2 side. The length of the second light guide 17 is shorter than the width W of the first light guide 10 in the Y direction, and further includes the second light guide 17 and the light source 12. The length dimension L is shorter than the width dimension W. Furthermore, the Y2 side end of the light source 12 and the Y1 side end of the second light guide 17 protrude in the Y direction from the Y direction ends 10e and 10f of the first light guide 10, respectively. It is positioned so as not to.

  The first reflecting surface 17 a formed on the second light guide 17 is a surface that reflects light toward the first light guide 10, and the first reflecting surface 17 a includes the light source 12. A light emitting means for emitting light incident from the light radially is provided. As the emitting means, a white reflecting sheet may be provided on the opposite side to the reflecting direction as shown in FIG. 2, and the emitting means may be white along the uneven surface of the first reflecting surface 17a. It may be formed by printing, or may be one that can be emitted radially by adjusting the shape of the triangular prism-shaped notch shown by the first reflecting surface 11a, or the triangular prism-shaped notched surface. Further, it may be provided with a diffusion shape that is further roughened. When the above-described emitting means is provided, even if the length of the second light guide 17 is shorter than the width W of the first light guide 10, the light from the light source 12 is emitted. The light is diffusely reflected by the first reflecting surface 17 a and transmitted to the entire first light guide 10.

  Further, as shown in FIG. 5, which is a view taken in the direction of the arrow 5 in FIG. 4, the second reflecting surface 17b can be provided with the emission means similar to the first reflecting surface 17a. Therefore, even if the length of the second light guide 17 is shorter than the width of the first light guide 10, the Y1 direction is longer than the length of the second light guide 17. It can be diffused widely in the Y2 direction. Therefore, the region of the first light guide 10 outside the both end portions of the second light guide 17 can also function as a light emitting surface.

  6 is a plan view showing a mobile phone as an example of an electronic device equipped with the surface light emitter 1A, FIG. 7 is a sectional view taken along line 7-7 in FIG. 6, and FIG. 8 is 8-8 in FIG. It is sectional drawing when cut | disconnecting with a line.

  As shown in FIG. 6, the cellular phone 20 is provided with an operation button group 21 including a dial button by pressing type and other buttons, and a display unit 30. Inside the cellular phone 20, the surface light emitter 1 </ b> A is provided on the back side of the operation button group 21. The surface light emitter 1 </ b> A is arranged so that the operation button group 21 faces the plane 10 t of the first light guide 10 and the plane 11 t of the second light guide 11. The operation button 21a of the unit faces the plane 11t.

  As shown in FIG. 7, the cellular phone 20 is provided with a substrate 23 that is laminated on the surface on the illumination side of the surface light emitter 1A. The substrate 23 is made of a synthetic resin such as PET and is transparent and has high light transmittance. A predetermined circuit pattern is formed on the substrate 23, and a tact switch 24 for generating an operation feeling is fixed as a detection means at a position facing each operation button of the operation button group 21. However, the detection means is not limited to the tact switch 24, and may be formed of a metal contact formed in a dome shape or an elastic member provided with a contact.

  In the mobile phone 20, light emitted from the light source 12 (not shown) is reflected by the first light guide 10 by the first reflecting surface 11 a of the second light guide 11, and the first The light is reflected by the main reflection surface 10 a of the light guide 10, is emitted from the flat surface 10 t on the illumination side, and passes through the substrate 23. The transmitted light illuminates the back side of the operation button group 21 and causes the operation button group 21 to emit light. The light from the light source 12 is reflected by the second reflecting surface 11b of the second light guide 11 and emitted from the flat surface 11t to illuminate the back side of the operation button 21a.

  By mounting such a surface light emitter 1A at a predetermined position of the mobile phone 20, it is possible to secure a wider light-emitting surface for illuminating than before, and when forming the casing of the mobile phone 20. The formation of useless space can be reduced.

  The surface light emitters 1A and 1B can also be applied as a member for illuminating the thin display unit 30. FIG. 8 is a cross-sectional view showing an example of the display unit 30. The display unit 30 can be installed in an electronic notebook such as a PDA (Personal Digital Assistant), an electronic dictionary, or other electronic devices.

  As shown in FIG. 8, a rectangular display window 40a is formed in the housing 40, and a protective plate 41 made of a transparent resin such as acrylic resin is fitted in the display window 40a.

  A liquid crystal display panel 42 is provided inside the housing 40. The liquid crystal display panel 42 has a pair of detection substrates 31 and 32 formed of transparent glass or synthetic resin, and an X electrode 31x and a Y electrode 32y are arranged in a matrix on the opposing surfaces of the detection substrates 31 and 32. Is formed. The X electrode 31x and the Y electrode 32y are each formed of a transparent electrode such as ITO (indium tin oxide), and liquid crystal is sealed between the detection substrates 31 and 32.

  A diffusion plate 43 is provided on the back side of the liquid crystal display panel 42. The diffusion plate 43 is made of, for example, a glass sheet or a plastic sheet having a light diffusing function by forming a rough surface such as ground glass, or a light transmitting material such as plastic, acrylic or polymethyl methacrylate (PMMA). It is made of a sheet-like synthetic resin in which a milky white pigment is contained in an excellent resin. When the diffusion plate 43 is interposed, the back surface of the liquid crystal display panel 42 provided on the front surface can be illuminated uniformly.

  Then, the surface light emitter 1A or 1B of the present embodiment is disposed on the back side of the diffusion plate 43. The display unit 30 may be colored by providing a color filter or the like between the detection substrates 31 and 32 as necessary.

  In the display unit 30 thus formed, the light emitted from the light source 12 is emitted from the Z1 plane 10t of the first light guide 10 and Z1 of the second light guide 11. The light is emitted from the side plane 11t. Therefore, since the area of the liquid crystal display panel 42 facing the flat surface 11t of the second light guide 11 can also be illuminated, a wide illumination area can be secured and the width dimension S1 of the outer frame of the housing 40 can be reduced. It becomes possible to set.

  In the surface light emitters 1A and 1B of the respective embodiments, the light source 12 is provided on both sides of the second light guide 11 so that light is introduced from both end faces of the second light guide 11. May be.

The top view when the surface-emitting body of the 1st Embodiment of this invention is seen from the illumination side, 2 arrow view of FIG. FIG. The top view which shows the surface light-emitting body of the 2nd Embodiment of this invention, View from arrow 5 in FIG. A plan view showing a state when mounted on a mobile phone as an application example of a surface light emitter, Sectional drawing when cut | disconnected by 7-7 of FIG. Sectional drawing when cut along line 8-8 in FIG.

Explanation of symbols

1A, 1B Surface light emitter 10 First light guide 10a Main reflection surface 10e, 10f Both end portions 11, 17 Second light guide 11a, 17a First reflection surface 11b, 17b Second reflection surface 12 Light source 12a Light emitting diodes 13a, 13b, 14 Reflective sheet 15 Transparent film 16 Case 16a Opening

Claims (8)

Surface is the light emitting surface, adjacent to the side surface extending in the Y direction of the first and light body guide, the first light guide body main reflection surface that reflects light toward the light emitting surface to the bottom surface is provided Then , the width dimension in the X direction orthogonal to the Y direction is shorter than the width dimension in the X direction of the first light guide, and the second light guide is oriented in the Y direction of the second light guide. and a light source through which light enters the inside of the second light guide body from the end face,
The surface of the second light guide is a light emitting surface, and the light from the light source is guided to the side surface extending in the Y direction on the opposite side of the surface adjacent to the first light guide. the first reflecting surface is provided for reflecting the body, a second reflecting surface for reflecting light from the light source toward the light emitting surface of the second light guide body have been found on the bottom surface ,
A plurality of operation buttons that are each illuminated with light from the light source are provided on the operation unit disposed on the front side of the first light guide and the second light guide, and the operation buttons are An illumination device , wherein the illumination device is arranged in both of a region facing the light emitting surface of the first light guide and a region facing the light emitting surface of the second light guide. Adjacent to a first light guide having a light emitting surface and a main reflecting surface provided on the bottom surface for reflecting light toward the light emitting surface, and a side surface extending in the Y direction of the first light guide. Then, the width dimension in the X direction orthogonal to the Y direction is shorter than the width dimension in the X direction of the first light guide, and the second light guide is oriented in the Y direction of the second light guide. A light source for allowing light to enter the second light guide from the end surface;
The surface of the second light guide is a light emitting surface, and the light from the light source is guided to the side surface extending in the Y direction on the opposite side of the surface adjacent to the first light guide. A first reflecting surface that reflects toward the body is provided, and a second reflecting surface that reflects light from the light source toward the light emitting surface of the second light guide is provided on the bottom surface;
A display panel that transmits light is provided on the front side of the first light guide and the second light guide, and the display panel faces the light emitting surface of the first light guide. An illumination device, wherein the illumination device is arranged over both the region and the region facing the light emitting surface of the second light guide. The illumination according to claim 2, wherein a diffusion plate that diffuses light is provided between the light emitting surface of the first light guide, the light emitting surface of the second light guide, and the display panel. apparatus. On the first reflecting surface, a plurality of concavo-convex portions that reflect light from the light source toward the first light guide body extend in the Z direction orthogonal to both the X direction and the Y direction and are in the Y direction. And a plurality of concavo-convex portions that reflect light from the light source toward the light emitting surface of the second light guide body, and extend in the X direction. A plurality of concavo-convex portions are provided at intervals in the Y direction, and the main reflection surface reflects light reflected by the first reflection surface toward the light emitting surface of the first light guide. The illumination device according to any one of claims 1 to 3, wherein the illumination device extends in the Y direction and is spaced apart in the X direction. A length dimension of the second light guide in the Y direction is shorter than a width dimension of the first light guide in the Y direction , and the second light guide and the light source are The illumination device according to any one of claims 1 to 4, wherein the illumination device is arranged so as not to protrude from a side surface extending in the X direction of one light guide. The illumination device according to claim 5 , wherein the first reflecting surface spreads and reflects light radially toward the first light guide. The illumination device according to any one of the first to the light guide and the second light guide body claims 1 are connected through an adhesive film having a transparent or light diffusing 6. The first light guide body and the second light guide body housed in a casing, according to claim 1, the side surface each other of the first light guide body and the second light guide member is brought into close contact The illumination device according to any one of Items 7 to 7 .

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