JPH0616979U - display - Google Patents

Abstract

(57) [Abstract] [Purpose] The shape of the light-emitting element is difficult to see, and a complete composite color light-emitting display can be obtained clearly, and the display directivity is good and the dot density is high and the display can be miniaturized. The purpose is to provide a container. [Structure] A circuit board 1 on which a plurality of light emitting elements 3 are mounted,
A light-transmissive cover body 2 provided on the upper surface of the circuit board 1.
A plurality of concave portions 21 for accommodating the light emitting elements 3 for one dot are provided in the surface of the light transmissive cover body 2, and the surface of each concave portion 21 is used as the light diffusing rough surface 21a. It has a feature.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a display device that is installed in a control device or an information guide device and displays various variable information.

[0002]

[Prior art]

 Conventionally, various types of display devices are known. For example, the display device shown in FIG. 5 includes a circuit board 61 on which a plurality of light emitting elements 62 are mounted, and a transparent resin case body 63 that is provided by being attached to the upper surface of the circuit board 61. Has a plurality of through holes (accommodation vacant chambers) 64 corresponding to one dot of the light emitting element 62. In each of the through holes 64, the light emitting elements 62 that form a pair of a red light emitting element 62a and a green light emitting element 62b are fitted and individually housed. A transparent film sheet 65 is attached to the upper surface of the transparent resin case body 62 to close the upper opening surface of each through hole 62a. Further, the display shown in FIG. 6 includes a circuit board 71 on which a plurality of light emitting elements 72 are mounted, and an upper surface of the circuit board 71, that is, a plurality of light emitting elements forming a pair of a red light emitting element 72a and a green light emitting element 72b. The transparent resin coating layer 73 integrally coats the surface including 72. In each of the above display devices, the light emitting element blinks in response to a signal from the circuit board to display various kinds of information.

[0003]

[Problems to be solved by the device]

 In all of the above conventional displays, the light emitting element is covered with a cover body (transparent resin film layer) made of transparent resin. Therefore, the shape of the light emitting element itself, the pattern of the circuit board, the wiring wire, and the like are directly exposed, which is not preferable as a display device. In addition, in a color display in which multiple light-emitting elements of different emission colors are used as the same display dot, for example, when it is necessary to turn on the red light-emitting element and the green light-emitting element at the same time and display with a composite color of orange light, In such a structure in which the light emitting element is simply surrounded by the transparent cover body as described above, the red and green light emitting points (light source points) are directly visible. In other words, in addition to the orange light, the red and green light source points can be seen in detail, and the orange light, which is the originally emitted color, becomes incomplete, resulting in a poor display quality as a whole. Further, in recent years, there has been a demand for a display device which has a large number of dots in the same area and is compact and capable of precise display. By the way, with the current light emitting diode mounting technology, it is easy to densely mount small light emitting elements. However, since the conventional transparent resin cover body shown in FIG. 5 has a structure in which a large number of through holes are formed in the surface, there is a limit to the dot density in the resin molding technology, and the desired miniaturization can be realized. Absent. On the other hand, in the method of forming the transparent resin coating layer shown in FIG. 6, since the resin is simply interrupted, the problem of difficulty in miniaturization does not occur, but the coating layer is transparent. Each light source point is visible and complete mixed color light cannot be obtained, and there are disadvantages such that the light emission between dense light emitting elements interferes with each other.

The present invention solves the above problems, makes it difficult to form the shape of a light emitting element and the like, can clearly obtain a complete synthetic color light emitting display, and has a high dot density and can be miniaturized. The purpose is to provide.

[0005]

[Means and Actions for Solving the Problems]

 In order to achieve this purpose, the display device of this invention has the following configuration. The display device is composed of a circuit board on which a plurality of light emitting elements are mounted and a light transmissive cover body provided on the upper surface of the circuit board. One dot of the light emitting element is provided in the surface of the light transmissive cover body. It is characterized in that a plurality of recesses for accommodating the are provided, and the surface of each recess is a rough surface for light diffusion.

In the display device having such a structure, a large number of recesses are formed inwardly in the surface of the transparent resin cover body, and the surfaces of the recesses are roughened. A light emitting element for one dot (for example, two light emitting elements for red and green) is housed in each of the recesses. Therefore, the form of the light emitting element or the like surrounded by the concave and convex rough surface cannot be visually observed accurately in appearance. Further, the lighting light of each light emitting element does not directly pass through the transparent cover body, but becomes diffused light on the rough surface of the concave and convex portions and goes out of the transparent cover body. Therefore, the light source point where the light emitting element is turned on cannot be seen, and when two light emitting elements are simultaneously illuminated, a complete mixed color light of red and green (orange light) is obtained, and the overall display is excellent. . In addition, since the surface of the light emitting element is surrounded by the concave and convex portions having the rough surface, the display directivity angle is wide and the display can be seen well in the lateral direction, and the directivity of the display is improved. Furthermore, since a plurality of recesses are formed on the inner surface of the transparent resin plate, resin molding is easier and dot density can be increased, and a compact and highly accurate display device can be obtained as compared with forming through holes. it can.

[0007]

【Example】

 FIG. 1 is a perspective view for explaining a main part of a concrete embodiment of a display device according to the present invention.

The display includes a circuit board 1 and a light-transmitting cover body 2 provided on the upper surface of the circuit board 1. The circuit board 1 is a well-known printed wiring board, which has a wiring pattern on its surface, and a plurality of light emitting elements (light emitting diodes) 3 are mounted on this wiring pattern. In the embodiment, the red light emitting diode 3a and the green light emitting diode 3b are set as one set and have the same display dot. Each of the light emitting diodes 3a and 3b is electrically connected to the wiring pattern of the substrate 1 by the electrode portion 31 and the wire bonding 32. Further, as shown in FIGS. 1 and 3, common and individual leads (pins) 33 are projecting outward from the substrate 1 in each light emitting element 3.

The light-transmitting cover body 2 is made of a hard or soft transparent resin plate (acrylic resin plate, polycarbonate resin plate, etc.) and is formed to have substantially the same size as the circuit board 1. The transparent resin cover body 2 is a transparent plate having a constant thickness and has a plurality of inwardly facing recesses 21 provided in the surface thereof. In the embodiment, as shown in FIG. 4, 16 × 16 recesses 21 are provided in the vertical and horizontal directions to form a total of 256 recesses 21. The surface of each recess 21 is formed as a rough surface 21a (see FIG. 2). That is, the surface of each recess 21 is processed to have a satin finish, and, for example, the portion directly above the light emitting element 3 is set to have a concave lens shape. The recess 21 has a hemispherical cross section and is formed in a size to accommodate the light emitting element (3a, 3b) 3 and is set so as to individually surround each light emitting element 3.

In the display device having such a configuration, a large number of recesses 21 recessed inward are provided in the surface of the transparent resin cover body 2, and the surface of the recesses 21 is formed as the rough surface 21a. Then, one dot of the light emitting element (red light emitting element 3a and green light emitting element 3b) 3 is housed in each recess 21a. Therefore, the form of the light emitting element 3 itself, which is covered by the concave portion (rough surface 21a), the wiring pattern of the circuit board 1, and the presence of the bonding wire 32 cannot be seen accurately from the outside, and the display device is not displayed. The appearance is good. When the red light emitting element 3a and the green light emitting element 3b are turned on at the same time, the projected light of each light emitting element 3a, 3b does not directly pass through the transparent cover body 2 but is formed by the rough surface 21a of the recess 21. It becomes diffused light and goes out of the transparent cover 2. Therefore, not only the lighting light source points of the light emitting elements 3a and 3b cannot directly appear, but also complete mixed color light (orange light) is projected to the outside, and the overall display feeling is improved. Further, since the light emitting element 3 is surrounded by the concave and convex portions 21 having a rough surface, the display directivity angle is wide and the display can be seen well in the lateral direction, and the directivity of the display is improved. Further, since the plurality of recesses 21 are formed on the inner surface of the transparent resin plate, the resin molding is easier and the dot density can be increased as compared with the formation of the through holes, and a compact and highly accurate display device can be obtained. it can.

In the embodiment, the recess 21 having a hemispherical cross section is shown. However, in practice, the recess 21 may be a substantially square hole instead of the hemisphere.

[0012]

[Effect of device]

 In this invention, as described above, a plurality of recesses for accommodating one dot of light emitting elements are provided on the inner surface of the light-transmitting cover body that covers the upper surface of the circuit board on which the plurality of light emitting elements are mounted. Since the concave-convex rough surface is formed, the concave portion of the rough concave-convex surface cannot reveal the form of the light emitting element itself, the wiring pattern, the presence of the bonding wire, and the like, and the appearance is good as a display. In addition, since the light emitted from the light emitting element is diffused by the uneven rough surface and then projected outward, the light source point of the light emitting element cannot be seen from the outside, and a perfect mixed color light (orange light) is emitted to the outside. And the overall display feeling becomes good. In addition, since the surface has a structure in which the light emitting element is surrounded by concave and convex portions having a rough surface, the display directivity angle is wide and the display can be seen well from the lateral direction, and the directivity of the display is improved. Furthermore, since only a large number of recesses are formed in the transparent resin plate, the resin molding technology is simple, the dot density can be increased, and a compact and accurate display device can be obtained. It has an excellent effect achieved.

[Brief description of drawings]

FIG. 1 is a partial perspective view showing a partial cross section of a display according to an embodiment.

FIG. 2 is a cross-sectional view of a main part showing an example display device.

FIG. 3 is a side view showing an example display.

FIG. 4 is a plan view showing a transparent resin cover body of an example display.

FIG. 5 is a cross-sectional view of a main part of a conventional display device.

FIG. 6 is a cross-sectional view of an essential part showing another conventional display device.

[Explanation of symbols]

 1 Circuit Board 2 Transparent Resin Cover 3 Light-Emitting Element 21 Recess 21a Rough Surface

Claims (1)

[Scope of utility model registration request] 1. A circuit board on which a plurality of light-emitting elements are mounted and a light-transmissive cover body provided on the upper surface of the circuit board, and one dot of light is emitted within the surface of the light-transmissive cover body. A display device characterized in that a plurality of recesses for accommodating elements are provided, and the surface of each recess is a rough surface for unevenness for light diffusion.