JPH08185130A - Dot matrix light emitting display with light shielding louver - Google Patents

Abstract

PURPOSE: To provide a dot matrix light emitting display with a highly reliable light shielding louver which does not entail the mispositioning and deficiency of strength of the light shielding louver on the front surface of a display, has the good heat radiatability from the light shielding louver, eliminates the possibility for the occurrence of the destruction and disconnection of light emitting elements and the warpage, distortion, crack, peel, etc., of the light emitting display by a difference in the coefft. of thermal expansion and contributes to an additional improvement in visibility. CONSTITUTION: A mask plate 2 of a rubber elastic material formed with many through-holes 21 and a convex lens assembly plate 3 of a rubber elastic material formed with many convex lenses 31 are adhered in superposition on the front surface of a wiring board 1 arranged with the many LED light emitting elements 6. Further, light shielding eaves plate 43 are disposed between the top end edges and upper and lower openings of opening plate 42 formed with many openings 41 to form the light shielding louver 4. The opening plates 42 of the light shielding louver 4 are adhered to the front surface of the convex lens assembly plate 3. Thermal stresses are absorbed by the mask plate 2 of the rubber elastic material and the convex lens assembly plate 3 and the thermal conductivity of the light shielding louver 4 is improved by adhesion of the opening plates 42. The visibility is improved by the convex lens assembly plate 3 and the light shielding louver 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dot matrix light emitting display with a light-shielding louver, which has improved visibility, heat dissipation, warpage, distortion and the like.

[0002]

2. Description of the Related Art Various types of dot-matrix light-emitting displays have been developed so far, and the applicant of the present invention has developed a large number of L
A dot matrix light emitting display in which a mask plate having a large number of through holes is adhered to the front surface of a wiring board provided with ED light emitting elements, and each LED light emitting element is housed in each through hole to form a large number of light emitting dots. The body has already been developed.

This dot-matrix light-emitting display has the advantage of good visibility because it has a large apparent light-emitting dot despite the use of a small LED light-emitting element, but it can be used outdoors in bright places. In the case of use, it is necessary to attach a light-shielding louver made of a metal plate or the like to the front surface of the light emitting display to shield the direct sunlight so that the visibility is not impaired.

[0004]

However, when the light-shielding louver made of a metal plate or the like is attached to the front surface of the light-emitting display body with an adhesive, the internal stress due to the temperature environment change due to the difference in thermal expansion coefficient between the two. Occurs, which may cause breakage or disconnection of the light emitting element, and easily cause warping, distortion, cracks, peeling, etc., so far, it was decided to attach the four corners of the light shielding louver with screws, etc. Since a large loose hole or the like can absorb the difference in thermal expansion and contraction, there is a problem that the light shielding louver is easily displaced.

When the light-shielding louver is attached with screws or the like as described above, the light-shielding louver itself must have a certain level of strength, but if the light-emitting display has a small dot size, the thickness of the light-shielding louver is small. I have no choice but to thin
There is a problem that the strength and mounting strength of the light shielding louver itself are insufficient. Moreover, when the light-shielding louver is attached with a screw or the like, the light emitting display and the light-shielding louver do not come into close contact with each other, so that the thermal conductivity is poor, and therefore, there is a problem that heat generated from the LED light-emitting element is difficult to be radiated through the light-shielding louver.

Further, in the above-mentioned light emitting display, since it is difficult to collect the light emitted from the LED light emitting element, there is room for improvement so that the brightness is increased by the light collection to further improve the visibility.

The present invention has been made in view of the above problems, and it is an object of the present invention to prevent displacement of the light-shielding louver and lack of strength and to provide good heat dissipation from the light-shielding louver. Destruction and disconnection of the light emitting element due to the difference in thermal expansion coefficient, and warpage, distortion, cracks, peeling, etc. of the light emitting display body do not occur, and the visibility can be further improved.
An object of the present invention is to provide a highly reliable dot matrix light emitting display with a light-shielding louver.

[0008]

In order to achieve the above object, a dot matrix light emitting display with a light-shielding louver according to the present invention has a large number of through holes formed on the front surface of a wiring board on which a large number of LED light emitting elements are arranged. A mask plate made of a rubber elastic body is adhered, the LED light-emitting element is housed in each through hole, and a convex lens collective plate made of a rubber elastic body having a large number of convex lenses corresponding to each through hole is adhered to the mask plate. Along with
A shading louver is formed by providing a shading louver between at least the upper edge of the opening having a large number of openings and the upper and lower openings, and the shading louver's opening is adhered to a convex lens assembly plate to attach the convex lens to the opening of the opening. It is characterized by having faced to.

Preferably, the mask plate and the convex lens collective plate are formed of a rubber elastic body having a Young's modulus of 500 g / mm ² or less, and the thickness of the mask plate and the flat plate portion of the convex lens collective plate on which the convex lens is not formed. The total thickness is 0.5 mm or more and 3.0 mm or less.

[0010]

According to the present invention, a mask plate made of a rubber elastic body is provided on the front surface of the wiring board, and a convex lens collecting plate made of a rubber elastic body is also provided.
When the opening plates of the light-shielding louver are overlapped and adhered, the stress due to the thermal expansion and contraction of the wiring board and the light-shielding louver opening plate is absorbed and alleviated by the mask plate and the convex lens collective plate, so even if the four members are adhered, warp, distortion, Does not cause cracks or peeling. In particular, when the mask plate and the convex lens assembly plate are made of a rubber elastic body having a Young's modulus of 500 g / mm ² or less and the total thickness of both is 0.5 mm or more and 3.0 mm or less, stress absorption and relaxation effects Is remarkable.

Further, since the above-mentioned adhesion improves the thermal conductivity, the heat generated in the LED light emitting element of the wiring board is conducted through the mask plate, the convex lens collective plate and the aperture plate of the light shielding louver, and the heat radiating fins. The light-shielding louver, which also functions as a heat-shielding louver, efficiently radiates heat to the outside air and suppresses temperature rise to a low level. On the other hand, since the light emitted from the LED light emitting element is condensed by the convex lens of the convex lens collecting plate, the brightness is increased, and the visibility is further improved in combination with the effect of blocking the external light by the light shielding louver.

Further, since the light shield louver is integrated with the convex lens collective plate by adhering the aperture plate to the convex lens collective plate, the strength of the light shield louver is sufficient even if the light shield louver aperture plate and the light shielding eaves plate are thin. Reserved.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view showing an embodiment of a dot matrix light emitting display with a light-shielding louver according to the present invention, FIG. 2 is a partially enlarged vertical sectional view of the same embodiment, and FIG. 3 is a mask plate of the same embodiment. It is a partial cross-sectional view of a convex lens assembly plate.

This light-emitting display with a light-shielding louver comprises a wiring substrate 1, a mask plate 2, a convex lens collective plate 3 and a light-shielding louver 4 which are bonded and integrated, and 16 × 16 light emitting dots 10 are formed vertically and horizontally. An example is shown. That is, this light-emitting display with a light-shielding louver has a through hole 21 on the front surface of the wiring board 1 in which 16 × 16 LED light-emitting elements 6 are arranged vertically and horizontally.
Adhere the mask plate 2 formed by 16 × 16 vertically and horizontally,
While accommodating each LED light emitting element 6 in each through hole 21,
A convex lens 31 corresponding to each through hole 21 is provided in the vertical and horizontal directions 16 × 16.
The convex lens collecting plate 3 formed individually is adhered to the front surface of the mask plate 2, and the opening plate 42 of the light-shielding louver 4 in which 16 × 16 openings 41 are formed vertically and horizontally is adhered to the front surface of the convex lens collecting plate 3, By exposing the convex lens 31 to each opening 41, 16 × 16 light emitting dots 10 are formed vertically and horizontally.

The wiring board 1 has a vertical 16-axis structure on the front surface of a copper-clad laminate or ceramic board using glass epoxy resin as a base material.
Book conductive pattern (for example, Y pattern group on the cathode side)
Is formed by means such as etching, and a horizontal 16
Book conductive pattern (for example, X pattern group on the anode side)
As shown in FIG. 2, the conductive pattern 11b on the back surface is led out to the front surface of the wiring substrate 1 for each light emitting dot 10 through the through hole 12. Then, the LED light emitting element 6 is fixed on the lead-out portion with a conductive paste such as silver paste, and is connected to the conductive pattern 11a on the surface of the substrate by the bonding wire 7, and XY
It constitutes a matrix lighting control circuit. Further, on the back surface of the wiring board 1, the leads 7 of the conductive patterns 11a and 11b are provided in a protruding manner.

The mask plate 2 and the convex lens assembly plate 3 adhered to the front surface of the wiring board 1 are made of a rubber elastic body, preferably a rubber elastic body having a Young's modulus (elastic modulus) of 500 g / mm ² or less. The total thickness T of the plate 2 and the flat plate portion of the convex lens assembly plate 3 on which the convex lens is not formed is 0.5 mm or more and 3.0 mm or less, preferably 0.8 mm or more and 2.0 mm or less. Is set to. The Young's modulus of the mask plate 2 and the convex lens collective plate 3 is 50
When it is made of a so-called high-rigidity material larger than 0 g / mm ² ,
When the thermal expansion coefficients of the wiring substrate 1, the mask plate 2, the convex lens collective plate 3, and the light shielding louver 4 are different, thermal stress is generated due to the change in temperature environment, and warping, distortion, cracks, peeling, and the like occur. Even if the mask plate 2 and the convex lens collective plate 3 are formed of a rubber elastic body, if the total thickness T is less than 0.5 mm, the mask plate 2 and the convex lens collective plate 3 have insufficient stress absorbing and relaxing action. Similarly, since warp, distortion, crack, peeling and the like are likely to occur, it is difficult to achieve the object of the present invention in any case. Specific examples of the rubber elastic body having a low Young's modulus as described above include silicone rubber, neoprene rubber, urethane rubber and the like. Among them, silicone rubber is excellent in heat resistance and weather resistance, and Young's modulus changes with time. It is particularly preferably used because it has a small amount.

The through hole 21 of the mask plate 2 efficiently reflects and emits the light from the LED light emitting element 6 to the front surface.
It is formed in a mortar shape with a forward spread as shown in FIGS. 2 and 3, and its inner peripheral surface is a white or silver-based light reflecting surface. Then, in order to improve the display contrast, the surface of the mask plate 2 is a black light non-reflective surface. In addition, a transparent encapsulating material 9 is filled into the through hole 21 and hardened so that the mounting portion of the LED light emitting element 6 and the wire bonding portion in the through hole 21 are sealed so as not to be corroded by an external gas or moisture. are doing. As with the mask plate 2, silicone rubber is suitable for the sealing material 9.

The thickness and size of the through hole 21 are the same as those of the LE.
It is preferable that the volume of the D light emitting element 6 is set to the minimum required for sealing and sealing because the front emission of light becomes higher. Then, as shown in FIG. 3, the front opening angle α of the through hole 21 is set to 3
It is desirable that the thickness t of the mask plate 2 is within a range of 0 to 60 ° and that the thickness t of the mask plate 2 is within a range of 0.4 to 2.5 mm. In this case, if the thickness t of the mask plate 2 is less than 0.4 mm,
Since the through holes 21 are shallow and have a flat mortar shape, there is a possibility that the sealing material 9 may not sufficiently seal the LED light emitting elements 6 and the like. On the other hand, when the thickness t of the mask plate 2 is larger than 2.5 mm, the reflection efficiency of the light in the through hole is lowered, the luminance of the light emitting dot is lowered, the amount of the rubber elastic body used as the material is increased, and the light emitting Only the inconvenience such as an increase in the thickness size of the whole display body is caused, and there is almost no further merit in terms of absorption and relaxation of stress, sealing property and the like. The through hole 21 may accommodate a plurality of LED light emitting elements 6 depending on the case.

The convex lens assembly plate 3 adhered to the front surface of the mask plate 2 is made of the same rubber elastic body as the mask plate 2, and a transparent material is most suitable. This convex lens assembly plate 3
The convex lenses 31 corresponding to the through holes 21 of the mask plate 2 are formed by arranging 16 × 16 vertically and horizontally, and each convex lens diameter R is
The area ratio of the light emitting display surface is set to be in the range of about 30 to 50%. In this case, each of the convex lenses 31 has better light-converging properties in the up-and-down direction than in the left-right direction, and is preferably formed in a horizontally-long substantially hemispherical shape capable of converging light in the height range of the obliquely downward viewpoint. . When the convex lens 31 having such a shape is used, the visibility at the practical viewing position is significantly improved. The thickness of the flat plate portion of the convex lens assembly plate 3 is 0.1 mm or more, preferably about 0.4 mm. This is because if the thickness is too thin, the adhesion workability deteriorates, and if it is too thick, light leakage to adjacent dots occurs.

The light-shielding louver 4 adhered to the front surface of the convex lens assembly plate 3 is made of a metal such as aluminum or a heat resistant plastic such as polycarbonate or Noryl resin, and corresponds to the convex lens 31 of the convex lens assembly plate 3 in 16 ×.
A structure is provided in which a light shielding eaves plate 43 is provided between the upper edge of an opening plate 42 having 16 openings 41 formed vertically and horizontally and the upper and lower openings.
The entire surface is made of a black light absorbing surface to improve the display contrast and prevent the visibility from being impaired by the reflection of light.

As described above, the through hole 2 is formed in one light emitting dot 10.
In the example in which 1 and the convex lens 31 correspond to each pair, 16
The x16 dot structure is suitable for a light emitting display body having a relatively small dot size of about 40 mm square to 200 mm square.

The aperture plate 42 of the light shielding louver 4 and the light shielding eaves plate 43
The plate thickness of is preferably 0.5 mm or less for a light-emitting display having a small dot size with a light-emitting dot pitch of 4 mm or less. Even if it is thin as described above, it is sufficiently bonded and integrated with the convex lens collective plate 3. It is possible to obtain excellent practical strength. Further, it is desirable that the protruding length of the light-shielding eaves plate 43 be set to be approximately the same as the mutual distance between the light-shielding eaves plates. If the protruding length of the light-shielding eaves plates 43 is longer than the mutual interval of the light-shielding eaves plates, the light-shielding eaves plate 43 becomes an obstacle when the light-emitting display body is looked up from diagonally below, but the light-shielding eaves plate 43 is not used.
If the projecting length is too short, absorption and blocking of direct sunlight from above will be insufficient, and in either case, it will be difficult to satisfactorily improve visibility. Note that the light-shielding eaves plate 43 may be provided with a slight slanting inclination.

As the adhesive for adhering the wiring board 1, the mask plate 2, the convex lens collective plate 3, and the light-shielding louver 4 to each other, a silicone rubber-based adhesive or an epoxy resin-based adhesive is used. When the convex lens assembly plate 2 and the convex lens assembly plate 3 are made of silicone rubber, a silicone rubber adhesive is preferably used.

When the light-shielding louver 4 as described above is adhered to the front surface of the convex lens assembly plate 3 and the convex lens 31 is made to face the opening 41 of the aperture plate 42 to form the light-emitting dot 10, direct sunlight or the like from above will shield the light-shielding louver. Since the light-shielding eaves plate 43 of No. 4 absorbs and blocks the light, the display relative brightness of the light-emitting display body is increased and the display contrast is improved. Moreover, since the heat conductivity to the light shielding louver 4 is improved by the adhesion, the heat generated in the LED light emitting element 6 of the wiring board 1 is applied to the mask plate 2 and the convex lens collective plate 3.
Also, heat is efficiently radiated to the outside air from each light-shielding eaves plate 43 that conducts through the opening plate 42 of the light-shielding louver 4 and also serves as a heat radiation fin. In particular, when the light-shielding louver 4 is made of a metal-based material such as aluminum having a high thermal conductivity, the heat radiation property is significantly improved. Therefore, the arrangement density of the LED light emitting elements 6 is increased to form a light emitting display body having high brightness, or the LED light emitting elements 6 are used.
It is possible to obtain a more reliable light-emitting display body in which the temperature rise is suppressed to a low level while maintaining the arrangement density. Also,
As described above, the stress caused by the thermal expansion / contraction difference among the wiring board 1, the mask plate 2, the convex lens collective plate 3, and the light-shielding louver 4 is different from that of the mask plate 2 made of a rubber elastic body having a low Young's modulus. Since it is sufficiently absorbed and relaxed by the convex lens collecting plate 3, even if the four members are bonded together, the LED light emitting element is not damaged or broken, and the light emitting display body is not warped, distorted, cracked or peeled. Of course, there is no displacement of the light-shielding louver as in the case of conventional screw fastening,
From these points as well, the reliability can be greatly improved.

In the above embodiment, 16 × 16 openings 4 are provided.
The light-shielding louver 4 having the number 1 is adhered to the convex lens assembly plate 3. For example, four light-shielding louvers having 8 × 8 openings 41, which are divided into four, are arranged side by side and adhered. You may make it adhere side by side.

On the contrary, one light shielding louver 4
On the other hand, the wiring board 1, the mask plate 2, and the convex lens collective plate 3 may each be configured as a plurality to form an integrated light-emitting display. Further, one opening 41 of the light-shielding louver 4 may be provided with a plurality of convex lens collective plates 3. The LED light emitting elements 6, the through holes 21, and the convex lenses 31 may be formed in an array so that the convex lenses 31 of FIG.

FIG. 4 and FIG. 5 are an exploded perspective view and a partially enlarged sectional view showing such a second embodiment, which is an example suitable for a large dot size of about 150 mm square or more with an 8 × 8 dot configuration. is there.

That is, the light-emitting display body with the light-shielding louver is
The mask plates 2 are adhered to the four wiring boards 1 respectively, and the four convex lens assembly plates 3 are adhered to each mask plate 2 to form four light emitting display bodies. The convex lens collective plate 3 is adhered to the aperture plate 42 of one light-shielding louver 4 so that the plurality of convex lenses 31 face one aperture 41.

The light-shielding louver 4 has 8 × 8 large square rectangular openings 41 arrayed in the aperture plate 42 so that the 8 × 8 light-emitting dots 10 are formed, and the light-shielding louver 4 emits four light. A structure in which a frame wall is integrally formed around the opening plate 42 so as to also serve as a case of the display body, and the light-shielding eaves plate 42 is provided so as to project obliquely downward between the upper edge of the opening plate 42 and the upper and lower openings. Has become. Then, a plurality of LED light emitting elements 6 are assembled and arranged on the wiring board 1 so that a plurality of LED light emitting elements 6 correspond to one opening 41 of the light shielding louver 4 and form one light emitting dot. Similarly, the mask plate 2 formed by collecting a plurality of through holes 21 and the four convex lens collecting plates 3 formed by collecting a plurality of convex lenses 31 are adhered to each other, and 4 × 4 dot light emission is performed. A convex lens aggregate plate 3 is formed by forming a display body and arranging four of the light emitting display bodies.
Is integrated with the aperture plate 42 of the light-shielding louver 4 to form a light-emitting display body with a light-shielding louver of 8 × 8 dots. When one light emitting dot 10 is composed of a plurality of through holes 21 and convex lenses 31 as in the second embodiment, the through hole size and the convex lens diameter can be set regardless of the dot size. At this time, the LED light emitting element 6, the through hole 21, and the convex lens 31 all correspond to each other at a ratio of 1: 1 and the through hole size is set to the minimum necessary for housing and sealing one LED light emitting element. It is preferable from the viewpoint of improving the front reflection efficiency. Further, the convex lens diameter R is preferably set so that the area ratio of the light emitting display surface is 30% or less as low as possible from the viewpoint of improving the visibility of the display. Further, by mixing LED light emitting elements having different light emitting colors in the set of LED light emitting elements, it is possible to obtain a display body in which light emitting dots emit light in various colors.

Since the specific structures of the wiring board 1, the mask plate 2, the convex lens collecting plate 3 and the like are the same as those in the above-mentioned embodiment, the same members are designated by the same reference numerals in FIGS. 4 and 5.
Description is omitted.

Such a light emitting display with a light-shielding louver also
Visibility is improved by the convex lens 31 and the light-shielding louver 4,
The heat dissipation from the light shielding eaves plate 41 of the light shielding louver is good,
It goes without saying that the stress absorption and relaxation of the mask plate 2 and the convex lens assembly plate 3 can prevent warpage, distortion, cracks, peeling, and the like of the light emitting display.

[0033]

As is clear from the above description, the dot matrix light emitting display with a light-shielding louver according to the present invention has the light-shielding louver's light-shielding function and the convex lens assembly even if it is installed outdoors in a bright place. Visibility is good due to the light condensing action, and because the heat dissipation through the light-shielding louver is good,
It is possible to increase the arrangement density of the LED light emitting elements to obtain a high-luminance light emitting display, or to keep the arrangement density of the LED light emitting elements unchanged to provide a highly reliable light emitting display that suppresses a temperature rise. Moreover, since the stress due to the thermal expansion / contraction difference between the wiring board and the light-shielding louver is sufficiently absorbed and relaxed by the mask plate and the convex lens assembly plate, warping, distortion, cracks, peeling, etc. do not occur, and in the case of conventional screw fastening As a result, the light-shielding louver will not be displaced, and even if the light-shielding louver has a small thickness, sufficient practical strength can be obtained by adhering it to the mask plate. It has various remarkable effects such as being preferably applicable to a light emitting display having a small light emitting dot size.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a dot matrix light emitting display with a light-shielding louver according to the present invention.

FIG. 2 is a partially enlarged vertical sectional view of the embodiment.

FIG. 3 is a partial cross-sectional view of a mask plate and a convex lens collective plate of the same embodiment.

FIG. 4 is an exploded perspective view showing another embodiment of the dot matrix light emitting display with a light-shielding louver of the present invention.

FIG. 5 is an enlarged partial sectional view of the embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Wiring board 2 Mask plate 21 Through hole 3 Convex lens assembly plate 31 Convex lens 4 Light-shielding louver 41 Opening 42 Opening plate 43 Light-shielding eaves plate 6 LED light emitting element T Total thickness of mask plate and flat lens part of convex lens assembly plate 10 Luminous dot

Claims (2)

[Claims] 1. A mask plate made of a rubber elastic body having a large number of through holes is bonded to the front surface of a wiring board having a large number of LED light emitting elements, and the LED light emitting elements are housed in the respective through holes. , A convex lens collective plate made of a rubber elastic body having a large number of convex lenses corresponding to the respective through holes adhered to the mask plate, and further, a light shielding eaves plate between at least the upper edge and the upper and lower openings of the opening plate having a large number of openings. Is provided to form a light-shielding louver, and the aperture plate of the light-shielding louver is adhered to a convex lens collective plate so that the convex lens faces the aperture of the aperture plate. 2. The mask plate and the convex lens collective plate are 500 g /
It is made of a rubber elastic body having a Young's modulus of ² mm ² or less, and the total thickness of the mask plate and the flat plate portion of the convex lens collective plate on which the convex lens is not formed is 0.5 mm or more,
The dot matrix light emitting display with a light-shielding louver according to claim 1, which is 3.0 mm or less.