JPH073363Y2 - Light guide plate lighting device - Google Patents

Description

The present invention relates to a light guide plate illuminator, and more particularly to an illuminator that is used in audio equipment such as a car stereo and has an improved illumination effect with a simple structure.

[Conventional technology]

2. Description of the Related Art Conventionally, a light guide plate illumination device used for a display and an operation panel of a car stereo or the like is made of an illumination source 1 such as a lamp and a transparent material such as acrylic resin as shown in FIG. A light guide plate 2, a reflector plate 4 such as a printer paper or an art paper arranged on the back surface of the light guide plate 2, and a display pattern screen arranged on the front surface of the light guide plate 2 with characters or patterns. It was composed of 5 mag. Reference numeral 6 denotes a light shielding plate for preventing the light from the illumination source 1 from directly illuminating the front surface.

In the light guide plate illumination device as described above, the light emitted from the illumination source 1 is reflected by the inner wall of the light guide plate 2 and guided along the length direction of the light guide plate. Then, a part of the light illuminates the pattern screen 5 on the front surface of the light guide plate to display characters and patterns. Further, in the apparatus shown in FIG. 2, a reflection plate 4 made of printable paper or bright colored art paper is provided on the back surface of the light guide plate 2, and the light leaked from the back surface of the light guide plate 2 is reflected to front face the light guide plate. The amount of light passing through is increased, the illumination effect by the light guide plate 2 is increased, and the display contrast of the design and characters on the pattern screen 5 is increased.

However, in such a conventional type, since the reflecting plate 4 made of art paper or printic paper is provided as a separate component on the back surface of the light guide plate, the number of assembling steps of the apparatus becomes complicated and the cost becomes high. was there.

In addition, the above art paper or printer paper,
Since the reflection coefficient is relatively small, all the light leaked from the back surface of the light guide plate 2 is not reflected but partially absorbed.

[Problems to be solved by the device]

In view of the above-mentioned problems in the conventional type, the present invention, in a light guide plate illuminator, substantially completely reflects the light leaked from the back surface of the light guide plate to improve the illumination effect, reduce the number of assembly steps of the device, and reduce the cost. The purpose is to reduce.

[Means for Solving the Problems]

According to the present invention, in order to solve the above-mentioned problems in the conventional type, a reflection coefficient much larger than that of an insulator is provided at a portion of the printed circuit board arranged on the back surface of the light guide plate, facing the back surface of the light guide plate. A structure is used that forms a conductive pattern layer that has and that reflects light almost completely.

[Action]

In the present invention, a conductive pattern layer that is usually used for connecting a plurality of circuit components on a printed circuit board is used as it is, and is used as a reflective layer having the same function as that of a conventional reflector (FIG. 2). There is. In general, since the conductive pattern layer is formed of a metal such as copper foil, its reflection coefficient is much larger than that of a reflection plate made of an insulating material such as art paper or print paper. Therefore, the reflection efficiency is improved, and the light leaked from the back surface of the light guide plate is almost completely reflected without being absorbed.

Thus, in the present invention, the loss of illumination light is almost eliminated, and the illumination effect of the light guide plate is improved as compared with the conventional case. Further, since it is not necessary to purposely provide art paper or printable paper, it is possible to reduce the number of assembly steps of the apparatus and the cost.

Furthermore, since the conductive pattern layer has conductivity, it is possible to prevent static electricity resulting from the operation of the operation switch provided on the printed board.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. Figure 1a
1 illustrates a light guide plate lighting device according to an embodiment of the present invention.
The apparatus shown in FIG. 1 includes an illumination source 1 such as a lamp, a light guide plate 2 formed of a transparent resin, a printed circuit board 3 on which, for example, operation switches (not shown) and other circuit components are attached, a pattern on which characters and patterns are applied. The screen 5, the light shielding plate 6, and the conductive pattern layers 7 and 7 ′ formed on the printed circuit board 3 are configured.

FIG. 1 b is a front view showing the printed circuit board 3. On the printed circuit board 3, a conductive pattern layer 7 (here, an example is shown) for connecting the circuit components to each other and a conductive pattern layer 7'used as a reflection layer are simultaneously formed in the same step. It Reference numeral 11 is a switch mounting hole, and 12 is a through hole of the lamp 1.

In the light guide plate illumination device as described above, the light emitted from the illumination source 1 passes through the light guide plate 2 and irradiates the pattern screen 5 to illuminate and display characters and patterns on the pattern screen 5. In this case, the conductive pattern layer 7'provided on the printed circuit board 3 is also used to illuminate the pattern screen 5 because the light that has escaped to the back surface of the light guide plate 2 is almost completely reflected and is used to irradiate the pattern screen 5. Instead, it becomes possible to effectively illuminate with the light guide plate.

As a result, in the case of realizing display illumination with a predetermined brightness (illuminance), it is not necessary to use the illumination source 1 having a large luminance. Therefore, the illumination source 1 may be a relatively small one, the area occupied by the illumination source 1 can be reduced, and the power consumption can be reduced.

[Effect of device]

As described above, according to the present invention, the conductive pattern layer that is normally used for connecting circuit components on a printed circuit board can be used as it is as a reflective layer without using a separate component such as print paper or art paper. Is possible,
The light guide plate can be effectively illuminated by the small-sized and low power consumption illumination source, and the number of assembling steps of the light guide plate illumination device can be reduced and the cost can be reduced. Further, according to the present invention, by utilizing the conductivity of the conductive pattern layer, it is possible to prevent static electricity due to the operation of the operation switch provided on the printed board.

[Brief description of drawings]

FIG. 1a is an explanatory view showing an outline of a light guide plate illuminating device according to an embodiment of the present invention, FIG. 1b is a front view showing a printed circuit board used in the device of FIG. 1a, and second. The figure is an explanatory view showing a conventional light guide plate illumination device. DESCRIPTION OF SYMBOLS 1 ... Illumination source, 2 ... Light guide plate, 3 ... Printed circuit board, 4 ... Reflector plate, 5 ... Pattern screen, 6 ... Light shielding plate, 7,7 '... Conductive pattern layer, 11 ... Switch mounting hole, 12 ... Illumination source penetration hole.

Claims (1)

[Scope of utility model registration request] 1. An illumination source, a light guide plate for guiding light from the illumination source,
A printed circuit board arranged on the back surface of the light guide plate; and a display pattern screen provided on the front surface of the light guide plate,
A light guide plate, characterized in that a conductive pattern layer having a reflection coefficient much larger than that of an insulator and almost completely reflecting light is formed on a portion of the printed board facing the back surface of the light guide plate. Lighting equipment.