JP2009059501A - Light emitting device using lightguide rod - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting device using a lightguide rod emitting light with good directivity and accurately illuminating a target region. <P>SOLUTION: The light emitting device with a lightguide rod 1 is equipped with a lightguide rod 2 which has an approximately circular shape in section and is formed of a transparent material and a light emitting element 3 which is disposed at an end portion of the lightguide rod 2. A reflection sheet 4 whose surface on the lightguide-rod side serves as a reflection surface is wrapped around the periphery of the lightguide rod 2 except a part thereof along the circumference direction. In the part of the periphery of the lightguide rod 2 that is not covered with the reflection sheet 4, a reflection processing portion 2a is provided to reflect light applied to the lightguide rod 2 from the light emitting element 3 to the outside of the lightguide rod 2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light emitting device using a light guide rod, in particular, a staircase, in which light from a light source is introduced into the light guide rod from one end of the light guide rod, and is emitted from the outer peripheral surface of the light guide rod to the outside of the light guide rod. The present invention relates to a light-emitting device using a light guide rod suitable for use as a foot lamp or the like.

As a light emitting device using this type of light guide rod, a light source such as a light emitting element is disposed at one end of a light guide rod made of a transparent material, and light introduced from the light source into the light guide rod is transmitted to the outer peripheral surface of the light guide rod. In other words, a light-reflecting portion formed along the longitudinal direction of the light-guide rod is reflected so as to be emitted from the outer peripheral surface of the light-guide rod excluding the reflection-processed portion (for example, Patent Document 1). , 2). FIG. 6 shows a cross-sectional view of the light guide rod in an example of the light emitting device having such a configuration. In this example, a reflection sheet 14 having a reflection surface on the light guide rod 12 side is wound around the outer periphery of the light guide rod 12 except for a part in the circumferential direction. A reflection processing portion 12a is formed in a part of the peripheral area around which the reflection sheet 14 is wound around the light guide rod 12, and the light reflected by the reflection processing portion 12a is reflected on the reflection sheet on the outer periphery of the light guide rod 12. 14 is emitted from the portion exposed from the light guide rod 11.
In the light emitting device having such a configuration, various measures are taken as the reflection processing portion 12a in order to prevent the light introduced into the light guide rod 12 from being attenuated with the distance from the light source. For example, in the thing disclosed in Patent Document 2, the area of the reflection processing portion 12a is increased according to the distance from the light source.
Japanese Patent Laid-Open No. 11-273435 JP 2004-226624 A

However, in the light-emitting device using the light guide rod having the above-described configuration, the light reflected by the reflection processing portion 12a on the outer periphery of the light guide rod 12 is a transparent material that is the material of the light guide rod 12, as shown in FIG. Since it passes through the inside and is radiated to the outside from the other part of the outer periphery of the light guide rod 12, the light diffuses over a wide range when passing through the transparent material.
When such a light emitting device using a light guide bar is installed on the underside of a step board at each step of a staircase and used as a foot lamp, for example, the illuminance unevenness increases in the width direction of the tread board and functions as a safe night light. I wonder if I get.
Also, when used as main lighting for a pendant or the like, there is a risk that the illuminance will be uniform in the depth direction on the step board of the staircase, and the stepped portion is difficult to understand.

  An object of the present invention is to provide a light-emitting device using a light guide bar that has good directivity of emitted light and excellent illumination.

The light-emitting device using the light guide rod of the present invention has a light-emitting element disposed at the end of a light-guide rod having a substantially circular cross section made of a transparent material, except for a part in the circumferential direction on the outer periphery of the light guide rod, A reflection film having a reflection surface on the light guide bar side is provided, and the light irradiated from the light emitting element to the light guide bar is reflected outside the light guide bar at a portion exposed from the reflection film on the outer periphery of the light guide bar A processing part is provided. The reflective film is wound around a light guide rod using a reflective sheet, for example.
According to this configuration, the light irradiated from the light emitting element into the light guide rod and reflected by the reflection processing portion does not pass through the transparent material that is the material of the light guide rod for a long time, and is almost directly outside the light guide rod. To be emitted. Therefore, the radiated light is not diffused over a wide range, the directivity of the radiated light from the light emitting device is improved, and the illumination property is excellent.

For example, the reflection processing unit is provided with a plurality of slits that are inclined with respect to the longitudinal direction of the light guide bar in the longitudinal direction. Each of these slits is inclined in a direction to reflect the light emitted from the light emitting element into the light guide bar toward the part exposed from the reflective film, with the boundary surface inside and outside the light guide bar serving as a reflection surface. is doing. The plurality of slits have a greater depth of cut as the slit is farther from the light emitting element.
When the reflection processing portion is formed with a plurality of slits in this way, the boundary surface inside and outside the light guide rod of the slit becomes a reflection surface, and light emitted from the light emitting element into the light guide rod is transmitted from the exposed portion without the reflection film. It can be reflected out of the light guide bar. Since a plurality of the slits are provided side by side in the longitudinal direction of the light guide bar, the slits can be reflected from each part in the longitudinal direction of the light guide bar. At this time, since each slit has a deeper cut depth as the slit is farther from the light emitting element, a portion facing the light emitting element is generated without being blocked by the slit on the near side with respect to the light emitting element. It is possible to reflect an average amount of light over the entire length direction.

  In the present invention, the light guide rod may be installed on the back of a step board. In the case of this configuration, since the directivity of the emitted light of the light emitting device using the light guide rod is good, it can be installed so that the illumination is concentrated on a portion slightly in the depth direction on the surface of the step board at each step portion. As a result, in each step, there is a contrast between the relatively dark nose part on the surface of the upper step board and the relatively bright part on the surface of the lower step board, so that the step part can be clearly recognized. it can.

  The light-emitting device using the light guide rod of the present invention has a light-emitting element disposed at the end of a light-guide rod having a substantially circular cross section made of a transparent material, except for a part in the circumferential direction on the outer periphery of the light guide rod, A reflection film having a reflection surface on the light guide bar side is provided, and the light irradiated from the light emitting element to the light guide bar is reflected outside the light guide bar at a portion exposed from the reflection film on the outer periphery of the light guide bar Since the processing portion is provided, the directivity of the emitted light is improved and the illuminating property is improved.

An embodiment of the present invention will be described with reference to FIGS. FIG. 1 (A) shows a front view of the light emitting device using a light guide rod of this embodiment. The light-emitting device 1 using a light guide rod includes a light guide rod 2 having a substantially circular cross section made of a transparent material such as acrylic resin, and a light-emitting element 3 such as an LED disposed at one or both ends of the light guide rod 2. Is provided. The light emitting element 3 is attached to the light guide rod 2 via a case 7 (FIG. 2), and is connected to a power source by wiring.
FIG. 1B is an enlarged cross-sectional view taken along the line IB-IB in FIG. As shown in the drawing, a reflection sheet 4 having a reflection surface on the light guide bar 2 side is wound around the outer periphery of the light guide bar 2 except for a part in the circumferential direction, and a reflection film is formed by the reflection sheet 4 is doing. The reflection sheet 4 is made of, for example, aluminum foil. Instead of the reflection sheet 4, a reflection film made of a vapor deposition layer or the like may be provided.

A reflection processing portion 2 a that reflects the light emitted from the light emitting element 3 into the light guide rod 2 to the outside of the light guide rod 2 is provided in the portion 2 b exposed from the reflection sheet 4 in the outer peripheral portion of the light guide rod 2. .
The reflection processing unit 2 a guides light that has directly reached the reflection processing unit 2 a from the light emitting element 3 in the light guide rod 2, and light that has been irradiated from the light emitting element 3 into the light guide rod 2 and reflected by the reflection sheet 4. Any structure may be used as long as it has a function of reflecting out of the rod 2, and various configurations can be adopted.

  FIG. 2 is a cutaway front view showing the reflective sheet 4 and the case 7 broken and the light guide bar 2 exposed. In this example, the reflection processing portion 2a is provided with a plurality of slits 2aa that are inclined with respect to the longitudinal direction of the light guide rod 2 and are arranged over the substantially entire length in the longitudinal direction. The slit 2aa is formed by laser processing or the like, but it is preferable to narrow the gap between the opposing surfaces on both sides of the slit 2aa. Each of these slits 2aa has a reflection surface at the boundary surface inside and outside the light guide rod of the slit 2aa, and reflects the light emitted from the light emitting element 3 into the light guide rod 2 toward the exposed portion 2b from the reflection sheet 4. It is inclined in the direction to make it. In addition, the slits 2aa that are farther from the light emitting element 3 have a greater depth of cut in the plurality of slits 2aa. The formation range of each slit 2aa is an arc-shaped portion along the exposed portion 2b of the light guide rod 2, as shown by hatching in FIG. 1B, and extends in the circumferential direction at a certain depth. .

  In using the light emitting device 1 using the light guide bar, the portion exposed from the reflection sheet 4 on the outer periphery of the light guide bar 2 is installed in the direction in which light is desired.

According to the light emitting device 1 using the light guide bar having this configuration, as shown in FIG. 3 (A), the light a irradiated from the light emitting element 3 and introduced into the light guide rod 2 is generated on the outer periphery of the light guide rod 2. The light is reflected by the reflection processing portion 2 a provided in the portion 2 b exposed from the reflection sheet 4 and emitted to the outside of the light guide rod 2. Specifically, the light is reflected by each slit 2aa constituting the reflection processing portion 2a and radiated out of the light guide bar 2. Reflection in each slit 2aa is performed by a portion that passes from the inside of the light guide rod 2 to the surface of the slit 2aa and a portion that passes through the slit 2aa and hits the surface on the opposite side of the slit 2aa. It is also good. Light that has been introduced into the light guide rod 2 and reflected by the reflection sheet 4, or reflected by the reflection processing portion 2 a in the light guide rod 2 and reflected again by the reflection sheet 4 is also reflected by the reflection processing portion 2 a. And emitted to the outside of the light guide rod 2.
Reflection at the reflection processing portion 2a is performed at each slit 2aa as described above. Since the slit 2aa is farther from the light emitting element 3, the depth of the cut is deepened. Uniform reflection is performed over a wide area, and uniform illumination can be achieved.

As described above, in the light emitting device 1, the light reflected by the reflection processing unit 2 a is directly emitted outside the light guide bar 2 without passing through the transparent material that is the material of the light guide bar 2. Therefore, the emitted light is not diffused over a wide range, and the directivity of the emitted light from the light emitting device 1 is improved. That is, as shown in comparison with FIGS. 3A and 3B, in the conventional example (FIG. 3B), since the light reflected by the reflection processing portion 12a passes through the transparent material, diffusion occurs. In this embodiment, directivity is improved because the light is directly reflected from the reflection processing portion 2a as shown in FIG. Thus, since directivity improves, the target illumination area can be illuminated effectively.
The light emitting elements 3 may be provided at both ends of the light guide rod 2, but because of excellent illumination properties as described above, necessary illumination is possible even when provided at only one end. When the light emitting element 3 is disposed only at one end, it is not necessary to provide wiring between both ends of the light guide rod 2, and the wiring system can be simplified.

4 and 5 show examples in which the light-emitting device 1 using the light guide rod is used as a step lamp for stairs. In this case, the light emitting device 1 is installed on the front surface side of the kick plate 6 on the back surface of the stepping plate 5 in each step portion, and the portion exposed from the reflection sheet 4 on the outer periphery of the light guide bar 2 (FIG. 1B) The surface of the lower step board 5 is directed to a part (a portion shown by hatching in FIG. 5) 5a slightly closer to the back.
As described above, when the light emitting device 1 using the light guide bar is installed, the directivity of the radiated light is good, so that the illumination is concentrated on a part of the step plate 5 on the surface of the step board 5 that is slightly in the depth direction. As a result, in each stepped portion, a contrast is generated between a relatively dark nose portion on the surface of the upper stepping plate 5 and a relatively bright kicked portion on the surface of the lower stepping plate 5, and the stepped portion is clearly recognized. be able to.

  The light-emitting device 1 using the light guide bar is not limited to the use example as shown in FIG. 4 used as a foot lamp, but is used for a portion where a line of sight is to be guided, such as a rising wall of a front door or other stepped portions, or for a normal production. It can also be used as a lighting.

(A) is a front view of the light-emitting device using a light guide rod according to one embodiment of the present invention, and (B) is an enlarged cross-sectional view taken along arrow IB-IB in (A). It is a partially broken front view along the longitudinal direction of the light guide bar. (A) is explanatory drawing of the light reflection in the light guide rod of the embodiment, (B) is explanatory drawing of the light reflection in the light guide rod of a prior art example. It is explanatory drawing of the usage example which used the light-emitting device using the same light guide rod as a step lamp of the stairs. It is the perspective view which looked down at the same staircase from the upper side. It is an expanded sectional view of the light guide bar in a conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Light-emitting device using light guide rod 2 ... Light guide rod 2a ... Reflection processing part 2aa ... Slit 2b ... Exposed part 3 ... Light emitting element 4 ... Reflective sheet 5 ... Tread board

Claims (3)

  A light-emitting element is arranged at the end of a light guide rod having a substantially circular cross section made of a transparent material, and a reflection film having a reflection surface on the light guide rod side is provided on the outer periphery of the light guide rod except for a part in the circumferential direction. And a reflection processing portion for reflecting light emitted from the light emitting element to the light guide rod to the outside of the light guide rod at a portion exposed from the reflection film on an outer periphery of the light guide rod. Light-emitting device using a light rod.   In Claim 1, the said reflective process part is provided with the slit which inclines with respect to the longitudinal direction of a light guide rod in order to arrange in the said longitudinal direction, and these each slit is a boundary inside and outside the light guide rod of this slit. The surface is a reflective surface, and is inclined in a direction in which light emitted from the light emitting element into the light guide rod is reflected toward a portion exposed from the reflective film, and the plurality of slits are formed in the light emitting element. Light-emitting device using a light guide rod with the depth of cut deeper as the slit is farther away.   The light-emitting device using a light guide rod according to claim 1 or 2, wherein the light guide rod is installed on the back of a step board.

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