JPS6210781Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel display device. For more information,
A display body such as characters or symbols is formed in a light-transmissive manner, a light guide plate is placed on the back side of this display body, and the light introduced into this light guide plate is emitted toward the display body, thereby displaying In a display device whose body is illuminated, the production of a mold for manufacturing the light guide plate is facilitated by devising a means for directing the light introduced into the light guide plate toward the display body. The aim is to provide a new display device.

FIG. 1 shows an example of a conventional display device. A is a display board, and a light-shielding film d is provided on the surface of a transparent substrate b, except for the portion that will become a display body c for characters, symbols, etc., thereby forming a light-transmitting display body c. There is. Denoted at e is a light guide plate made of a transparent material, which is placed on the back side of the display panel a, one end surface f of which serves as a light receiving surface, and the light receiving surface f faces the light bulb g. Further, a large number of conical recesses h are formed on the back surface of the light guide plate e corresponding to the display body c. Thus, the light from the light bulb g enters the light guide plate e from the light receiving surface f and is propagated within the light guide plate e by internal reflection. Of the light that enters the light guide plate e, the light that hits the conical concave point h is reflected by the concave point h and is emitted to the front of the light guide plate e, onto the display panel a. It passes through the display body c. Therefore, when viewing the display panel a from the front, the display body c appears to be shining. The amount of light that enters the light guide plate e and propagates within its thickness is large near the light receiving surface and decreases as it moves away from the light receiving surface f.
The formation density of the conical concave points h is increased at locations corresponding to the display bodies c that are far from the display body to prevent imbalance in brightness between the respective display bodies.

However, if the light intensity is controlled by the formation density of the conical recesses h as described above, it is technically extremely difficult to manufacture the part of the mold that corresponds to the conical recesses h, and requires a skilled technician. It takes time.
In addition, once the light guide plate is created using a mold, it is difficult to adjust the amount of light, and even if it is necessary to modify the relevant part of the mold (i.e., the part corresponding to the conical concave point), it is difficult to modify the mold. It also has some drawbacks.

Therefore, the present invention aims to solve the above-mentioned problems and provide a new display device in which a mold for molding a light guide plate can be easily manufactured and can be easily modified. A display body such as characters or symbols is formed in a light-transmissive manner, a transparent light guide plate is arranged on the back side of the display body, and a light source that supplies light is provided in the light guide plate, and the display body of the light guide plate is On the back surface corresponding to the body, a frosted surface consisting of frost-like fine irregularities is formed, and the number of fine irregularities per unit area is increased on the frosted surface far from the light source. It is characterized in that a frosted surface consisting of frost-like fine irregularities is also formed on the front surface of the light plate.

The details of the display device of the present invention will be explained below with reference to the embodiments shown in the accompanying drawings.

Reference numeral 1 designates a display board, which is formed by applying a light-shielding film 4 to the surface of a transparent substrate 2 made of a transparent material such as acrylic resin, except for portions that will become display bodies 3 such as characters and symbols. Thereby, the display body 3 is formed in a light-transmissive state.

Reference numeral 5 denotes a light guide plate made of a transparent material such as acrylic resin, one end surface 6 of which serves as a light receiving surface, and a light bulb 7 is disposed corresponding to this light receiving surface 6. or,
On the back surface of the light guide plate 5 at a location corresponding to the display body 3, there is a frosted surface 8 made of fine frost-like unevenness.
The fine unevenness constituting the frosted surface 8 is coarse nearer to the light-receiving surface 6 and finer farther from the light-receiving surface 6. That is, the number of microscopic asperities per unit area increases as the distance from the light receiving surface 6 increases. A frosted surface 9 made of fine frost-like unevenness is also formed on the front surface of the light guide plate 5 corresponding to the frosted surface 8 furthest from the light receiving surface 6.

Therefore, in such a display device, the light that enters the light guide plate 5 from the light receiving surface 6 passes through the frosted surface 8.
The light is reflected by the fine irregularities there, emitted forward, and then transmitted through the display body 3 formed on the display panel 1. Therefore, when viewing the display panel 1 from the front, the display body 3 appears to be shining due to the transmitted light. On the frosted surface 8 far from the light-receiving surface 6, the number of fine irregularities formed therein per unit area is increased.
Even though the amount of light reaching here is smaller than that near the light-receiving surface 6, the ratio of the light reflected by the fine irregularities to the amount of arriving light is high, and the unit area of light reflected toward the display body is The amount of hits is balanced. Furthermore, since a frosted surface 9 is formed on the front surface of the light guide plate 5 corresponding to the frosted surface 8 furthest from the light receiving surface 6, a portion of the light that has reached the frosted surface 9 is directed toward the display body 3. This can contribute to the brightness of the display body 3 that is farthest from the light source 7. That is, on the frosted surface 9, even light that would be internally reflected if it were a flat surface can be emitted to the outside of the light guide plate. The light can be emitted to the outside, and the brightness of a display body far from the light source 7 can be covered.

As described above, in the display device of the present invention, as a means of controlling the amount of light directed toward the light-transmissive display element, the frosted surface consisting of concave and convex portions is used as a means for controlling the amount of light directed toward the light-transmitting display. This makes it extremely easy to manufacture a mold for molding a light guide plate. That is, for example, an etching method can be used to form the portion corresponding to the frosted surface, and the size of the fine irregularities can be easily controlled by, for example, controlling the etching time. Furthermore, the work is easy when modifying the mold. In addition, a frosted surface consisting of fine frost-like unevenness is formed on the front surface of the light guide plate corresponding to the frosted surface far from the light source, making it easier to control the uniformity of brightness between each display element. can do.

In order to obtain a more uniform display, the front frosted surface 9 may be formed not only to correspond to the display body furthest from the light source, but also to correspond to the display body on the light source side. Alternatively, it goes without saying that the degree of roughness of the unevenness may be changed.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing an example of a conventional display device, and FIG. 2 is a vertical sectional view showing an example of an implementation of the display device of the present invention. Explanation of symbols, 3...Display body, 5...Light guide plate, 7
...Light source, 8...Frost surface on the back, 9...Frost surface on the front.

Claims (1)

[Scope of utility model registration request] A display body such as characters or symbols is formed in a light-transmissive manner, a transparent light guide plate is arranged on the back side of the display body, and a light source that supplies light is provided in the light guide plate, and the display body of the light guide plate is A frosted surface consisting of frost-like fine irregularities is formed on the back surface corresponding to the body, and the number of fine irregularities per unit area is increased on the frosted surface far from the light source, and a light guide plate corresponding to the frosted surface farther from the light source is formed. A display device characterized in that a frosted surface made of fine frost-like unevenness is also formed on the front surface.