JPH11134917A - Annular lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an annular lighting system that realizes a uniform annular illumination effect with a minimum light source. SOLUTION: This annular lighting system is equipped with an annular light guiding plate 1 and a light source 2 illuminating from its back side, and thus illuminates annularly. The annular light guiding plate 1 is equipped with a light guiding hole 7 composed of a surface 1a that is vertical and parallel to its normal direction and a projecting surface 1b formed on its outer circumferential edge at a certain angle, and a light guiding surface 1c that is tilted in the circumferential direction so as to reflect the incident light from the light guiding hole 7 formed on the back side of the annular light guiding plate 1. The projecting surface 1b of the light guiding hole 7 is formed protrusively more than the periphery of the annular light guiding plate 1 and uneven parts are formed on the light guiding surface 1c; the light source 2 is structure so as to face the projecting surface 1b of the light guiding hole 7 and to be placed out of the projecting range of the light guiding surface 1c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an annular illumination device which is effective for illuminating a periphery of a push button provided on a front panel portion of an audiovisual apparatus such as a radio-cassette, a mini-computer, and a video.

[0002]

2. Description of the Related Art Conventionally, an annular illuminator of this type is configured to uniformly illuminate a light source disposed within a projection range of a light guide surface of an annular light guide plate by using a light guide plate containing a diffusing material.

FIG. 3 shows the structure of a conventional annular illuminating device. In FIG. 3, a light source 17 is disposed within a projection range of a light guide surface of an annular light guide plate 16 containing a diffusing material. The light plate 16 is held between the front panel 13 and the printed wiring board 14 via a boss 13 a and an elastic locking piece 13 b provided on the front panel 13, and is fixed by screws 14.

[0004]

In order to obtain a uniform illumination effect in such an annular illumination device, a light source 17 must be used.
There is a demand for a light guide plate having a sufficient distance from the light source, having a diffusion effect containing a diffusion material, and a large number of light sources.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional problems, and has as its object to provide a ring-shaped lighting device that realizes a uniform ring-shaped lighting effect with a minimum number of light sources.

[0006]

SUMMARY OF THE INVENTION In order to solve this problem, an annular illuminating device according to the present invention comprises an annular light guide plate and a light source illuminating from the back side thereof so as to illuminate annularly. The annular light guide plate includes a light guide opening formed of a surface that is vertical and parallel to the radiation direction and a protruding surface formed at an outer peripheral edge thereof at a predetermined angle, and the light guide opening formed on the back side of the annular light guide plate. A light guide surface inclined in the circumferential direction so that light incident from the light port is reflected, and a protruding surface of the light guide port is formed to protrude from an outer periphery of the annular light guide plate, and the light guide surface has irregularities. Is formed, and the light source is arranged outside the projection range of the light guide surface in opposition to the projecting surface of the light guide opening. Thereby, a uniform annular illumination effect can be obtained with a minimum number of light sources.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present invention is an annular illumination device which is provided with an annular light guide plate and a light source illuminating from the back side thereof to illuminate annularly.
The annular light guide plate includes a light guide opening formed of a surface that is perpendicular and parallel to the radiation direction and a protruding surface formed at an outer peripheral edge thereof at a constant angle, and a light guide opening formed on the back side of the annular light guide plate. A light guide surface inclined in the circumferential direction so that the incident light is reflected, the projecting surface of the light guide opening is formed to protrude from the outer periphery of the annular light guide plate, and the light guide surface has irregularities. The light source is arranged outside the projection range of the light guide surface in opposition to the projecting surface of the light guide opening, and has a uniform annular illumination effect with a minimum number of light sources.

According to a second aspect of the present invention, in the annular light guide plate, a plurality of light guide openings are provided in a circumferential direction thereof, and a light source is arranged corresponding to the light guide openings. It has the function of illuminating uniformly.

According to a third aspect of the present invention, a rib is provided on the outer periphery of the annular light guide plate, and the annular light guide plate is inserted into a groove formed in a panel, thereby mounting and positioning the annular light guide plate. This has the effect of reducing the number of work steps.

According to a fourth aspect of the present invention, the inclined light guide surface of the annular light guide plate has irregularities in a direction intersecting the inclined direction, and the joint between the start end and the end of the light guide surface is made uniform. It has the effect of doing.

An embodiment of the present invention will be described below with reference to FIGS. (Embodiment 1) FIG. 1 shows a ring-shaped illumination device according to an embodiment of the present invention, where (a) is a rear view and (b)
Shows a side view, and (c) shows a perspective view.

In the figure, 1 is a transparent annular light guide plate, 2 is a light source, and the annular light guide plate 1 is illuminated by the light source 2. The annular light guide plate 1 has a boss 3 on the front panel 3.
a, between the printed circuit board 5 and the front panel 3 attached by screws 4 via the elastic locking pieces 3b,
It is arranged on the outer periphery of the operation component 6 attached to the printed wiring board 5 and is illuminated.

The ring-shaped light guide plate 1 has a light guide opening 7 composed of a surface 1a perpendicular to and parallel to the radiation direction and a protruding surface 1b formed at an outer peripheral edge thereof at a predetermined angle α, and a back surface of the ring-shaped light guide plate 1. And a light guide surface 1c that is formed on the side and is inclined in the circumferential direction so that light incident from the light guide opening 7 is reflected. The protruding surface 1b of the light guide opening 7 is formed to protrude from the outer periphery of the annular light guide plate 1, and the light guide surface 1c is formed with irregularities in a direction intersecting the inclined direction. Further, a rib 1d is provided on the outer periphery of the annular light guide plate 1, and when the annular light guide plate 1 is attached to the mounting hole 3c formed in the front panel 3 and the cylindrical portion 3d formed on the periphery thereof, The insertion position of the annular light guide plate 1 is determined by being inserted into the formed groove 3e.

The light source 2 has a protruding surface 1 b of the light guide port 7.
The light source 2 is mounted outside the projection range of the light guide surface 1c and soldered to the printed wiring board 5. Further, in the illustrated embodiment, the annular light guide plate 1 has a configuration in which two light guide ports 7 are provided in the circumferential direction thereof, and two light sources 2 are arranged corresponding to the light guide ports 7.

The operation of the annular illumination device of the first embodiment configured as described above will be described below.

First, light from the light source 2 disposed outside the projection range of the light guide surface 1c is incident from the light guide opening 7. At this time, the light from the light source 2 is emitted from the parallel surface 1a which is the starting end of the light guide port 7.
The light is projected on the inclined light guide surface 1c formed on the back surface of the annular light guide plate 2 and is guided in the circumferential direction until the end of the light guide surface 1c is formed on the light guide surface 1c. The light is diffused by the irregularities and the light guide surface 1c emits light. Thereby, the annular light guide plate 1 can be visually recognized from the beginning to the end of the light guide without any border.

As described above, according to the present embodiment, an annular illumination device having a uniform light guide surface can be realized, and the annular light guide plate can be easily positioned and fixed, so that the number of work steps can be reduced.

(Embodiment 2) FIG. 2 shows the annular light guide plate 1.
Of the parallel surface 1a and the protruding surface 1b constituting the light guide port 7 of
This is an example in which the parallel surface 1a is an uneven surface. As shown in FIG. 2, the light from the light source 2 arranged so that the light ray A is incident on the protruding surface 1b from a substantially right angle direction, while the light ray B on the parallel surface 1a is incident on the oblique direction. In this way, by forming the unevenness on the parallel surface 1a, the light B incident obliquely is also taken into the light guide surface 1c, and as a result, the portion 8 where the light A from the protruding surface 1b is difficult to be taken. To the light, and the lighting effect of this part is enabled.

[0019]

As described above, according to the present invention, there is provided an annular illuminating device which is provided with an annular light guide plate and a light source for illuminating the annular light guide plate from the back side thereof so as to illuminate annularly. A light guide opening formed of a surface that is perpendicular and parallel to the radiation direction and a protruding surface formed at an outer peripheral edge thereof at a fixed angle, and a light formed on the back side of the annular light guide plate and reflected from the light guide opening is reflected. A light guide surface inclined in the circumferential direction so as to be formed, the projecting surface of the light guide opening is formed to protrude from the outer periphery of the annular light guide plate, the light guide surface is formed with irregularities, and the light source is
It is arranged so as to face out of the projection range of the light guide surface in opposition to the projecting surface of the light guide opening, and a uniform annular illumination effect can be obtained with a minimum number of light sources.

Further, since the positioning can be easily performed by inserting into the groove formed in the panel, the number of working steps can be reduced.

[Brief description of the drawings]

FIG. 1A is a rear view of an annular illumination device according to a first embodiment of the present invention, FIG. 1B is a side view thereof, and FIG.

FIG. 2 is an enlarged view of a light guide opening of the annular illumination device according to the second embodiment of the present invention.

FIG. 3 (a) is a front view of a conventional annular lighting device, and FIG. 3 (b) is a side view thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Annular light guide plate 1a Parallel surface 1b Projection surface 1c Light guide surface 1d Rib 2 Light source 3 Front panel 3a Boss 3e Groove 5 Printed wiring board 7 Light guide port

Claims (4)

[Claims] 1. An annular illuminating device comprising an annular light guide plate and a light source illuminating from the back side thereof to illuminate annularly, wherein said annular light guide plate has a surface which is vertical and parallel to a radiation direction, and A light guide port formed of a protruding surface formed at a constant angle on the outer peripheral edge; and a light guide formed on the back side of the annular light guide plate and inclined in the circumferential direction so that light incident from the light guide port is reflected. A light surface, and a projection surface of the light guide opening is formed to protrude from an outer periphery of the annular light guide plate, and an unevenness is formed on the light guide surface. The light source faces the projection surface of the light guide opening. An annular illuminating device configured to be arranged outside a projection range of a light guide surface. 2. The annular illuminating device according to claim 1, wherein the annular light guide plate has a plurality of light guide openings provided in a circumferential direction thereof, and a light source is arranged corresponding to the light guide openings. 3. A structure in which a rib is provided on an outer periphery of the annular light guide plate, and the annular light guide plate is mounted and positioned by inserting the annular light guide plate into a groove formed in the front panel when attaching the annular light guide plate to the front panel. The annular illumination device according to claim 1, wherein the annular illumination device is provided. 4. The annular illumination device according to claim 1, wherein the inclined light guide surface of the annular light guide plate has irregularities in a direction intersecting the inclination direction.