JPH09129078A - Operation button lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the lighting of an operation button from differing by applying a specified structure to a plate-like light guide plate arranged on the back part of the operation button. SOLUTION: A plate light guide plate 22 is arranged on the back part of an operation button, and a lamp 21 is inserted to the hole 23 of the light guide plate 22. A conical inclined surface 26 is formed around the hole 23 on the back surface of the light guide plate 22, and concentric knurls 27 are formed around the hole 23 on the inclined surface 26. Since the same optical path is formed to the emitting direction of the light of the lamp 21 because of the formation of the concentric knurls around the hole 23 for inserting the lamp 21, the luminance of the light reflected by the inclined surface 26 and reaching the upper part is made constant, and the lighting of the operation button arranged above the light guide plate 22 is uniformed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation button lighting device used for an on-vehicle audio equipment or the like.

[0002]

2. Description of the Related Art FIG. 1 shows the front of an on-vehicle audio device. In FIG. 1, 1 is a device main body, 2 is a front plate of the device main body 1, 3 is an operation button that also serves as a power switch and a volume control, 4 is a cassette insertion slot for inserting a cassette, and 5 is a reception frequency band during radio reception. A display device for displaying (AM, FM), a reception frequency and the like, and displaying an operation mode, a tape running direction and the like when the cassette deck is operating, 6-1.
Reference numeral 1 is an operation button for preset tuning, 12 to 17 are operation buttons for controlling each operation of the radio receiver or cassette deck, and 18 and 19 are operation buttons for sound quality adjustment.

5 to 8 show a conventional operation button illumination portion. 5 to 8, 6 and 7 are operation buttons for preset tuning, 20 is a printed circuit board fixed in the apparatus main body 1, and a lamp 21 is soldered to the printed circuit board 20. There is. Reference numeral 22 denotes a plate-shaped light guide plate that guides the light emitted from the lamp 21 to the back side of the operation buttons 6, 7, and 8. The light guide plate 22 has a hole 23 into which the lamp 21 is inserted. ing. 24 is a light guide plate 2
2 is a plane-shaped sloping surface formed on the lower surface side, and on this sloping surface 24, linear knurls 25 are formed on both sides of the hole 23, as shown in FIGS. The light emitted from the lamp 21 directly illuminates the back surface of the operation buttons 6, 7, and 8, and the light incident on the light guide plate 22 is reflected upward by the inclined surface 24 on which the knurls 25 are formed to be reflected. It reaches the upper surface of 22 and illuminates the rear surface of the operation buttons 6, 7, and 8.

[0004]

However, in the above-mentioned conventional operation button lighting device, since the linear knurl 25 is formed on the flat inclined surface 24 of the light guide plate 22, the light emitted from the lamp 21 is emitted. There is a problem that the brightness of the light that illuminates the operation buttons 6, 7, and 8 via the guide plate 22 varies depending on the radiation direction of the light, resulting in uneven illumination. That is, in FIG. 5, light emitted from the lamp 21 in the X-axis (FIG. 6) direction and reflected by the inclined surface 24 and light emitted in the Y-direction that is different from the X-axis by a predetermined angle and reflected by the inclined surface 24. However, the illumination of the operation buttons 6, 7, and 8 was different from that of.

The present invention solves the above-mentioned conventional problems, and provides an operation button illumination device in which the illumination of the operation buttons does not vary.

[0006]

In order to achieve the above object, the present invention provides a plate-shaped light guide plate arranged on the back of an operation button, and a lamp inserted in a hole of the light guide plate. It is characterized by comprising a conical inclined surface formed on the back surface of the light guide plate with the hole as the center, and a knurl formed concentrically on the inclined surface with the hole as the center.

As described above, it is possible to provide the operation button illumination device in which the illumination of the operation button does not vary.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is a plate-shaped light guide plate arranged on the back of an operation button, a lamp inserted into a hole of the light guide plate, and the above-mentioned light guide plate. A conical inclined surface formed on the back surface of the guide plate with the hole as the center, and a knurl formed concentrically on the inclined surface with the hole as the center, the lamp insertion hole of the light guide plate. Since the concentric knurls are formed on the inclined surface centered at, the optical path of the light emitted from the lamp and incident on the light guide plate is the same regardless of the light emission direction of the lamp. The brightness of the light reflected by the inclined surface of the plate and reaching the back surface of the operation button is the same, the illumination of the operation button is uniform, and there is no variation in brightness.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. (Embodiment 1) The present embodiment and the conventional example are different from each other in the shape of the inclined surface formed on the light guide plate 22 and the shape of the knurl formed on this inclined surface. Description of the configuration is omitted. 2 to 4, 22 is a plate-shaped light guide plate, 23 is a hole formed in the light guide plate 22, and 26 is a conical inclined surface formed on the back side of the light guide plate 22. Holes 23 in the inclined surface 26
A knurl 27 having a concentric circle centered at is formed.

FIG. 3 is an enlarged view showing a sectional shape of a concentric knurl 27 formed on the inclined surface 26 of the light guide plate 22. FIG. 4 is a bottom view of the light guide plate 22, in which concentric knurls 27 are formed concentrically around the hole 23.

In FIG. 2, the light emitted from the lamp 21 directly illuminates the rear surface of the operation buttons 6, 7, and 8, and
The light incident on the light guide plate 22 has concentric knurls 27.
The light guide plate 2 is reflected upward by the inclined surface 26 on which the light guide plate 2 is formed.
2 reaches the upper surface and illuminates the rear surfaces of the operation buttons 6, 7, and 8.

By forming concentric knurls 27 around the hole 23 into which the lamp 21 is inserted, the same light path is formed in the light emitting direction of the lamp 21 on the inclined surface 26. Therefore, the brightness of the light reflected by the inclined surface 26 and reaching the upper part becomes the same, and the illumination of the operation buttons 6, 7, 8 arranged above the light guide plate 22 becomes uniform.

As described above, in the above-described embodiment, the knurls 27 that are concentric with the hole 23 into which the lamp 21 is inserted are formed on the inclined surface 26, and the knurls 27 are the same in the light emitting direction of the lamp 21. By forming the light path, the brightness of the light reflected by the inclined surface 26 and reaching the upper part can be made uniform, and the illumination of the operation buttons 6, 7, 8 arranged above the light guide plate 22 is uniform. It will be.

[0014]

As described above, according to the present invention, the brightness of the light reaching the back surface of the operation button through the light guide plate becomes the same, and the operation button can be uniformly illuminated.

[Brief description of the drawings]

FIG. 1 is a front view of a vehicle-mounted audio device that employs an operation button lighting device according to an embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the same embodiment.

FIG. 3 is an enlarged view of a main part of the embodiment shown in FIG.

FIG. 4 is a bottom view of the light guide plate of the same embodiment.

FIG. 5 is a top view of a conventional operation button lighting device.

FIG. 6 is a sectional view of the conventional example.

FIG. 7 is an enlarged view of a main part of a conventional example.

FIG. 8 is a bottom view of the conventional light guide plate.

[Explanation of symbols]

 6,7,8 Operation button 21 Lamp 22 Light guide plate 23 Hole 26 Slope 27 Knurled

Claims (1)

[Claims] 1. A plate-shaped light guide plate disposed on the back of the operation button, a lamp inserted into a hole of the light guide plate, and a cone formed around the hole on the back surface of the light guide plate. An operation button lighting device comprising an inclined surface and a knurl formed concentrically around the hole on the inclined surface.