JP2009177117A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device where not only optical interference between adjacent pixels is suppressed but also high density pixels are disposed, making the color of a device substrate pad less likely to be recognized. <P>SOLUTION: First to third pads are disposed on each of pixel regions E of the device substrate 2. A first pixel element 7 for emitting a red light in a conducting state is mounted on the first pad 3, and a second pixel element 8 for emitting a green light in a conducting state is mounted on the second pad 4. Furthermore, a third pixel element for emitting a blue light in a conducting state and forming the pixel, together with the first and second pixel elements 7, 8, is mounted on the third pad. A transparent sealing member 21 is disposed on the device substrate 2 to seal each of the pad and pixel element. A groove 22 is formed on the sealing member 21 to enclose each pixel element region E. A bottom end of the groove is set closer to a side of the device substrate 2 than to an edge of each pixel element, and a black pad cover member 25 is bonded to the sealing member 21 so as to cover a part of each pixel region E, and a light-passing hole 26 for allowing the light emitted by each pixel element to pass is made in the member 25. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a display device such as a full-color LED (light emitting diode) display in which one pixel is formed by three pixel elements that individually emit red, green, and blue light.

  2. Description of the Related Art Conventionally, an LED display in which blue, green, and red LED chips are mounted on a printed board is known (see, for example, Patent Document 1).

That is, in the LED display, a resin or ceramic cover member having a reflection layer on the inner surface and a cavity formed on a printed circuit board on which a conductive layer made of Au is formed is arranged. In addition, red, green, and blue LED chips that individually emit light of the three primary colors to form one pixel are disposed, and these chips are wire-bonded to a conductor layer located in the cavity. It is connected. Furthermore, the LED chip is sealed with a resin mold injected into the cavity. In this LED display, the surface of the cover member on the light emission observation surface side is preferably black for the purpose of improving the contrast.
Japanese Patent No. 3329573 (paragraphs 0004, 0019-0025, FIGS. 1 to 5)

  In the LED display described in Patent Document 1, since one pixel is partitioned by a cover member whose inner surface forms a reflective layer, light does not leak into adjacent pixels and color mixing occurs. However, since the cover member is used for this purpose, the number of parts is large. In addition, since each part of the cover member is formed to require a certain thickness, it becomes an obstacle when pixels are arranged with high density.

  Furthermore, since the black surface of the cover member is provided depending on the position of the cover member, it is not possible to cover the Au conductive layer located in the cavity surrounded by the cover member with the black surface of the cover member. Can not. For this reason, the color of the conductor layer on the printed circuit board side, that is, the gold color, is easily visible through the resin mold, and there is a need for improvement.

  An object of the present invention is to provide a display device that can suppress interference of light between adjacent pixel regions and is suitable for arranging pixels at a high density, and that makes it difficult to visually recognize the color of a pad provided on the device substrate. It is to provide.

  A first aspect of the present invention is a device substrate having a plurality of pixel regions each provided with first to third pads; and a semiconductor light emitting element mounted on the first pad and emitting red light in an energized state. A first pixel element comprising: a second pixel element comprising a semiconductor light emitting element mounted on the second pad and emitting green light when energized; and mounted on the third pad A third pixel element made of a semiconductor light emitting element that emits blue light in an energized state and forms a pixel together with the first and second pixel elements; and seals each pad and each pixel element Provided on the device substrate and having a groove formed so as to individually surround each pixel region, and the inner end of the groove is closer to the device substrate than the tip of each pixel element. A translucent sealing member; and each of the pixels Is characterized by comprising a; to form the light-passing section through which light passes emitted by containing the pad cover member of the disposed in the sealing member black so as to cover a portion of each pixel region.

  In the invention of claim 1, a printed circuit board can be suitably used as the device substrate, but other substrates can also be used. In the first aspect of the present invention, the pixel region includes a pixel element composed of first to third semiconductor light emitting elements that individually emit red, green, and blue light, and a pixel is formed by these pixel elements. It indicates a region and it is sufficient that at least one pixel is formed, and a chip-like LED, an organic EL element, or the like can be used for each pixel element. In the first aspect of the invention, the semiconductor light emitting element that emits red light means that it emits mainly red light, and its main emission wavelength is approximately 660 nm. Similarly, in the first aspect of the invention, the semiconductor light emitting element that emits green light means that it emits mainly green light, and its main emission wavelength is about 550 nm. Similarly, in the invention of claim 1, the semiconductor light emitting element that emits blue light indicates that it emits mainly blue light, and its main emission wavelength is about 460 nm. In the invention of claim 1, examples of the light-transmitting sealing member include synthetic resins such as silicone resins. In the invention of claim 1, the black pad cover member can be made of a synthetic resin material of the same type or different from the sealing member, and a black powder such as carbon powder mixed therein. It is preferable that the entire groove is filled. According to the first aspect of the present invention, the light passage portion of the pad cover member has a light passage hole formed in the pad cover member so as to face a part of the pixel region, or a pixel so as to face a part of the pixel region. It can be formed by a light passage groove provided in the pad cover member along the direction in which the regions are arranged.

  In the first aspect of the invention, the sealing member that seals the first to third pixel elements that emit different colors is formed so as to surround the pixel region in which the first to third pixel elements are mounted. And the rear end of the groove is closer to the device substrate side than the height position of the tip of each pixel element. Can be partitioned. For this reason, it is possible to suppress the interference of light, which is emitted from the pixels in one pixel region to the side and enters the pixel region adjacent to the pixel region and is mixed, by the groove. At the same time, since it is not necessary to use a dedicated member for suppressing the color mixture, the number of parts can be reduced. In addition, since the groove width of the sealing member may be narrow, it is suitable for arranging a plurality of pixels with high density.

  Furthermore, in the first aspect of the invention, since the black pad cover member is provided so as to cover a part of each pixel region, the contrast can be improved. In addition, the pad cover member prevents the pads on the apparatus substrate from being seen through, and makes it difficult to visually recognize the color of the pads.

  The invention of claim 2 is characterized in that, in the invention of claim 1, the opening of the groove is wider than the inner end of the groove, and the pad cover member is provided to fill the opening of the groove.

  In the invention of claim 2, a large proportion of the pad cover member occupies the display surface of the display device without being restricted by the size of the back end of the groove of the sealing member, in other words, with respect to the light passage portion. Since the ratio of the black pad cover member is increased, the contrast ratio can be increased.

  The invention of claim 3 is characterized in that, in the invention of claim 1 or 2, the light passage portion is provided so as to face each part of the first to third pixel elements.

  According to the invention of claim 3, a part of the light for display emitted from each pixel element is directly transmitted through the light regardless of the presence of the pad cover member that suppresses the see-through of the pad on the device substrate. Since it is emitted to the outside through the part, it is easy to take out light effectively.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the rear end of the groove of the sealing member is at the same height as the surface of the pad or the surface and the surface of the device substrate. It is characterized by reaching between.

  In the invention of claim 4, the effect of the groove of the sealing member for suppressing the light emitted from one pixel from the side into the adjacent pixel region and mixing the colors is enhanced, so that the adjacent pixel regions Can effectively suppress light interference.

  The invention of claim 5 is characterized in that, in the invention of claim 4, the pad cover member has a groove filling portion filled in the groove of the sealing member.

  According to the fifth aspect of the present invention, the groove filling portion of the black pad cover member filled in the groove obtains a light shielding action between adjacent pixel regions, and can reliably prevent light interference between pixels.

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects of the present invention, a boundary between the sealing member and the pad cover member is formed, and a light reflecting layer is provided therebetween. Yes. In the present invention, the light reflecting layer can be formed of white paint or silver plating.

  In the invention of claim 6, the light emitted from the first to third pixel elements toward the boundary with the black pad cover member is not blocked by the pad cover member, but is reflected by the light reflecting layer. Since the light is reflected, the amount of light passing through the light passage portion increases, and light can be extracted efficiently.

  According to the display device of the first aspect of the present invention, although it is possible to reduce the number of parts, it is possible to suppress light interference between adjacent pixel regions and to be suitable for arranging pixels at high density. The color of the pad that the device substrate has can be made difficult to visually recognize.

  According to the display device of the invention of claim 2, in the invention of claim 1, the ratio of the black pad cover member to the light passage portion on the display surface of the display device is further increased, and the contrast ratio can be increased. .

  According to the display device of a third aspect of the present invention, in the first or second aspect of the invention, there is an advantage that light for display emitted by each pixel element can be easily taken out through the light passage portion.

  According to the display device of a fourth aspect of the invention, in the invention of any one of the first to third aspects, the interference of light between adjacent pixel regions can be reliably suppressed.

  According to the display device of the fifth aspect of the present invention, in the fourth aspect of the present invention, it is possible to reliably prevent light interference between adjacent pixel regions.

  According to the display device of a sixth aspect of the present invention, in the invention of any one of the first to fifth aspects, the efficiency is further improved by the reflection on the light reflecting layer even though the black pad cover member is used. Can take out light well.

  A display device of the present invention, for example, an LED display (hereinafter abbreviated as a display) 1 according to the first embodiment will be described with reference to FIGS.

  The display 1 shown in FIG. 1 includes an apparatus substrate, for example, a printed circuit board 2, a first pixel element 7, a second pixel element 8, a third pixel element 9, a sealing member 21, a pad cover member 25, and each A control circuit (not shown) for controlling light emission of the pixel element is provided.

  The printed circuit board 2 has a plurality of pixel regions E on one side of the base 2a. The base 2a is black and is made of, for example, a multilayer printed wiring board. Each pixel area E indicates a square area, for example, a regular square area surrounded by vertical and horizontal grooves to be described later when the display 1 is viewed from the front. In the cross-sectional view of FIG. 3, for convenience of explanation, the pixel region E is shown as the length of the range occupied by it. The pixel regions E are arranged in a matrix form with a predetermined interval in the vertical and horizontal directions.

  As shown in FIGS. 2 and 5, the printed circuit board 2 includes a first pad 3 to a fourth pad 6 each having a square shape provided in each pixel region E. These pads 3 to 6 are individually arranged in a rectangular divided region obtained by further dividing the pixel region E into four equal parts. Thereby, when the display 1 is viewed from the front, each pixel region E has a shape of “rice”. Each pad 3-6 is made of Au. The first pad 3 to the third pad 5 are connected to a circuit pattern (not shown) included in the base 2a so as to be a positive potential, and the fourth pad 6 is included in the base 2a so as to be a negative potential. Connected to the circuit pattern.

  As shown in FIGS. 2 and 3, the first pixel element 7 is mounted on the first pad 3 by flip chip mounting. For the first pixel element 7, a chip-like semiconductor light emitting element, for example, a red LED chip that emits red light when energized is used. A second pixel element 8 is mounted on the second pad 4 by flip chip mounting. As the second pixel element 8, a chip-like semiconductor light emitting element, for example, a green LED chip that emits green light when energized is used. Similarly, the third pixel element 9 is mounted on the third pad 5 by flip chip mounting. As the third pixel element 9, a chip-like semiconductor light emitting element, for example, a blue LED chip that emits blue light when energized is used. 3 and 4, reference numeral 10 indicates a solder layer used for mounting the pixel elements 7 to 9.

  One pixel (or also referred to as an image point) of the display 1 is formed by the pixel elements 7 to 9. Each of the pixel elements 7 to 9 is formed by providing a light emitting layer on an element substrate made of sapphire, for example, and the other surface opposite to one surface of the element substrate provided with the light emitting layer is soldered to the pads 3 to 5. Yes. As representatively shown in FIG. 5, the electrode provided on the light emitting layer side of the first pixel element 7 is electrically connected to the common fourth pad 6 via the bonding wire 11, The electrode provided on the light emitting layer side of the pixel element 8 is also electrically connected to the common fourth pad 6 via the bonding wire 12. Similarly, the electrode provided on the light emitting layer side of the third pixel element 9 is also electrically connected to the common fourth pad 6 through the bonding wire 13. Therefore, energization to the first pixel element 7 to the third pixel element 9 is individually controlled through the first pad 3 to the third pad 5 by a control circuit (not shown). A pixel composed of pixel elements expresses a target color.

  The sealing member 21 is made of a translucent synthetic resin such as a transparent silicone resin. The sealing member 21 is provided on the printed circuit board 2 by filling the pads 3 to 6, the pixel elements 7 to 9, and the bonding wires 11 to 13, thereby sealing the pixel elements 7 to 9 and the like. is doing.

  The sealing member 21 has a groove. The groove refers to a groove 22 extending in the vertical direction (vertical direction in FIG. 1) of the printed board 2 and a groove 23 extending in the horizontal direction (left and right direction in FIG. 1) of the printed board 2. The vertical and horizontal grooves 22 and 23 are provided in a grid pattern so as to individually surround each pixel region E. These vertical and horizontal grooves 22 and 23 can be formed by excision with a dicing cutter or laser light irradiation, for example.

  The depths of the grooves 22, 23, in other words, the height A (see FIG. 3) of the deep ends of the grooves 22, 23 with respect to the back surface of the printed circuit board 2, is the tip of each pixel element 7-9 (that is, the light emission). It is closer to the printed circuit board 2 side than the layer), and as a more preferred example, it reaches the same height position as the surface of each pad 3-6 or between this surface and the surface of the base 2a. In FIG. 3, symbols B, C, and D all indicate dimensions indicating the height position with respect to the back surface of the printed circuit board 2, and symbol B indicates the height position of the tip of each pixel element 7-9. Reference numeral C indicates the height position of the surface of each of the pads 3 to 6, and reference numeral D indicates the height position of the surface of the base 2a. Therefore, B> C ≧ A> D is satisfied, and the inner ends of the grooves 22 and 23 do not reach the surface of the base 2a.

  The vertical and horizontal grooves 22 and 23 form a sealing portion 21a that is opposed to each pixel region E. At the same time, the sealing portions 21a adjacent in the vertical and horizontal directions are partitioned by the grooves 22 and 23 positioned therebetween.

  As shown in FIGS. 2 and 3, the pad cover member 25 is attached to the sealing member 21 so as to cover a part of each pixel region E. In the case of this embodiment, the pad cover member 25 has a plurality of light passing portions, for example, circular light passing holes 26 through which monochromatic light emitted from the light emitting pixel elements 7 to 9 or light mixed with these light passes. The sealing member 21 is covered. The pad cover member 25 is preferably filled with the grooves 22 and 23 as shown in FIG. In addition, the code | symbol 25a in FIG. 3 and FIG.4 (C) has shown the groove filling part which the pad cover member 25 had. The pad cover member 25 exhibits a black color by, for example, mixing carbon powder into a silicone resin that is the same material as the sealing member 21.

  When the sealing member 21 and the pad cover member 25 are made of the same material as described above, they not only have good compatibility with each other and high bonding strength, but also have the same thermal expansion and contraction, and also have a groove filling. Since the portion 25a functions as an anchor, it is preferable in that the pad cover member 25 is difficult to peel off from the sealing member 21.

  As shown in FIG. 2, each light passage hole 26 has a circular shape, for example, and faces the central portion of the front portion of each sealing portion 21a. At the same time, as shown in FIGS. 2 and 3, the display 1 is provided so as to face at least a part of each of the pixel elements 7 to 9 when viewed from the front. These light passage holes 26 can be formed by excision by laser light irradiation.

  The display 1 having the above configuration is manufactured by the following procedure.

  First, as shown in FIG. 4A, after the first pixel element 7 to the third pixel element 9 are individually mounted on the first pad 3 to the third pad 5 of the printed circuit board 2, respectively, The pixel elements 7 to 9 and the common fourth pad 6 are electrically connected by wire bonding. 4A to 4C representatively show the periphery of the third pixel element 9 and the fourth pad 6.

  Next, after supplying the uncured and liquid sealing member 21 so that the pixel elements 7 to 9 and the bonding wires 11 to 13 are filled, the sealing member 21 is heated and cured to form the pixel elements 7 to 9. Sealing is performed with a sealing member 21. After that, vertical and horizontal grooves 22 and 23 having a predetermined depth are formed in the sealing member 21 using a dicing cutter, as representatively shown in FIG. The grooves 22 and 23 thus formed are opened to both ends in the longitudinal direction and the surface of the sealing member 21, and the sealing portions 21 a in which the pixels are individually sealed by the grooves 22 and 23 are arranged vertically and horizontally. Formed with.

  Thereafter, the uncured and liquid pad cover member 25 is supplied so as to fill the entire sealing member 21 as shown in FIG. The pad cover member 25 is cured by heating. Accordingly, the pad cover member 25 is disposed so as to cover the sealing member 21. Finally, a plurality of light passage holes 26 are formed in the pad cover member 25 by laser processing. A front view of a part of the display 1 thus manufactured is shown in FIG. 2, and a sectional view of the same part is shown in FIG.

  In the display 1 having the above-described configuration, the sealing member 21 that seals the first pixel element 7 to the third pixel element 9 that emits different colors emits one pixel when the display 1 is viewed from the front. Grooves 22 and 23 are provided so as to surround the region E. At the same time, the grooves 22 and 23 are formed at a depth where the rear ends of the grooves 22 and 23 are closer to the printed circuit board 2 than the tips of the pixel elements 7 to 9.

  As a result, the pixel regions adjacent to each other are partitioned by the grooves 22 and 23 of the sealing member 21 when the display 1 is viewed from the front. In addition, in this case, since the rear ends of the grooves 22 and 23 reach the same height position as the surface of each of the pads 3 to 6 or between this surface and the surface of the base 2a of the printed circuit board 2, the sealing member The sealing portions 21 a of the sealing member 21 corresponding to each pixel region E are necessary and sufficiently partitioned by the grooves 22 and 23. For this reason, it is possible to suppress the interference of light, which is emitted from one pixel region to the side and mixed into the adjacent pixel region, by the grooves 22 and 23.

  In addition, since the black pad cover member 25 has a groove filling portion 25a filled in the grooves 22 and 23, the groove filling portion 25a shields light between adjacent pixel regions. Thereby, the display performance of the display 1 can be improved as the interference of light between the pixel regions can be more reliably prevented.

  Since the sealing member 21 is used to prevent light from being mixed between adjacent pixel regions as described above, it is not necessary to use a dedicated member for suppressing interference with light. Therefore, the number of parts of the display 1 can be reduced. In addition, the widths of the grooves 22 and 23 of the sealing member 21 may be narrow, which is suitable for arranging the pixels of the display 1 with high density while suppressing interference of light between the pixel regions.

  Furthermore, since the display 1 having the above-described configuration includes the black pad cover member 25 that covers a part of each pixel region E when viewed from the front, the contrast can be improved. In addition, the pad cover member 25 prevents the gold pads 3 to 6 from being seen through the printed circuit board 2, thereby making it difficult to visually recognize the colors of the pads 3 to 6.

  In the display 1 having the above-described configuration, the light passage holes 26 provided in the pad cover member 25 so as to face the respective pixel regions individually are formed on the first pixel element 7 to the third pixel element 9 when the display 1 is viewed from the front. It is provided so as to face each part. Thereby, regardless of the presence of the pad cover member 25 that suppresses the visibility of the colors of the pads 3 to 6, a part of the light for display emitted by the pixel elements 7 to 9 is directly The light can be emitted through the light passage hole 26. Therefore, it is easier to take out light more effectively than when all the light emitted from the pixel elements 7 to 9 is emitted outside the pad cover member 25.

  A second embodiment of the present invention will be described with reference to FIG. Since the second embodiment is the same as the first embodiment except for the matters described below, including the components not shown in FIG. 6, the same components as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment. The description is omitted.

  The second embodiment shown in FIG. 6 is different from the first embodiment in that the light passage portion is formed by a light passage groove instead of a hole. That is, the light passage grooves (light passage portions) are formed in the pad cover member 25 vertically and horizontally so as to face a part of the pixel region E when the display 1 is viewed from the front. In FIG. 6, the light passage groove extending in the vertical direction is indicated by reference numeral 26a, and the light passage groove extending in the horizontal direction is indicated by reference numeral 26b.

  Therefore, the vertical and horizontal light passage grooves 26a and 26b extend along the direction in which the pixel regions E are arranged, and are orthogonal to each other at the center of each pixel region E. Thereby, the black pad cover members 25 are arranged vertically and horizontally in a rectangular shape surrounded by the vertical and horizontal light passage grooves 26a and 26b. The pad cover member 25 includes a first pad 3 included in an arbitrary pixel area E when the display 1 is viewed from the front, a part of the first pixel element 7 mounted thereon, and a second The pixel region E is provided so as to cover the pad 4 and a part of the second pixel element 8 mounted thereon, and is adjacent to the one pixel region E in the vertical direction in FIG. The third pad 5 included, a part of the third pixel element 9 mounted thereon, and a part of the fourth pad 6 are provided. Therefore, when the display 1 is viewed from the front, all other parts than the one part are in a state of protruding from the pad cover member 25.

  Configurations other than those described above are the same as those in the first embodiment, including configurations not shown in FIG. Therefore, the second embodiment can solve the problems of the present invention by obtaining the same operation as the first embodiment. In addition, in the second embodiment, since the black pad cover members 25 are provided vertically and horizontally, the display generated by the first pixel element 7 to the third pixel element 9 included in each pixel region E is displayed. Since part of the light for the light can be directly emitted to the outside through the light passage grooves 26a and 26b, the light can be taken out more effectively.

  A third embodiment of the present invention will be described with reference to FIGS. Since the third embodiment is the same as the first embodiment except for the items described below, the same components as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and description thereof is omitted. The display according to the third embodiment includes the bonding wires 11 to 13 described in the first embodiment. However, the illustration thereof is omitted for convenience of description, and the pixel elements 7 to 9 are provided. The illustration of solder layers mounted on the corresponding pads 3 to 5 is also omitted for convenience of explanation.

  The LED display (display device) 1 according to the third embodiment has a quadrangular shape as shown in FIG. 7, and one side of the two parallel sides 1a and 1b extending in the lateral direction is positioned on the upper side. Used with the other side positioned on the lower side. In the display 1, the cross-sectional shape of the groove 23 extending in the horizontal direction among the grooves 22 and 23 included in the translucent sealing member 21 that seals the pixel regions E arranged vertically and horizontally is the depth of the groove 23. The opening of the groove 23 is wider than the end. Specifically, for example, as shown in FIG. 8, the shape of the cross section orthogonal to the direction in which the groove 23 extends is V-shaped. These grooves 23 extend straight in the horizontal direction in parallel with the horizontal arrangement of the pixel regions E, and are provided in parallel to each other so as to partition the sealing portions 21a adjacent in the vertical direction (vertical direction).

  As shown in FIG. 8, the width G of the back surface in contact with the printed circuit board 2 of the sealing part 21 a facing each pixel region E of the sealing member 21, and the front end of the sealing part 21 a farthest from the printed circuit board 2 The width H of the front surface 21b is G> H, and in this embodiment, the back surface and the front surface 21b are connected to each other at an oblique side surface. Therefore, the cross-sectional shape of each sealing portion 21a has a substantially equilateral trapezoidal shape as shown in FIG. In the present embodiment, the width G of the back surface and the vertical width of the pixel region E are equal.

  A black pad cover member 25 that covers a part of each pixel region E is provided so as to cover the sealing member 21 by filling the grooves 22 and 23 with their openings filled therein, and a light passage portion. A plurality of light passage grooves 26c are formed. The height I from the printed circuit board 2 to the surface of the pad cover member 25 is higher than the height of the sealing member 21, that is, the height J from the printed circuit board 2 to the surface 21b of the sealing member 21, thereby allowing light to pass. The groove 26c can be formed.

  As shown in FIG. 7, each light passage groove 26c is a slit-like groove extending straight in the same direction as the horizontal arrangement of the pixel regions E, and the bottom is a surface 21b of the sealing member 21 as shown in FIG. It is made. Therefore, the individual light passage grooves 26c traverse a plurality of pixels arranged in the lateral direction, and a part of these pixels, more specifically, each part of the first pad 3 to the fourth pad 6 The pad cover member 25 is partitioned into a plurality of parts.

  As shown in FIG. 8, a light reflecting layer 27 is provided between the sealing member 21 and the pad cover member 25 to form a boundary between them. The light reflecting layer 27 covers the inner surfaces of the grooves 22 and 23.

  The display 1 having the above configuration is manufactured by the following procedure.

  First, after the first pixel element 7 to the third pixel element 9 are individually mounted on the first pad 3 to the third pad 5 of the printed board 2, respectively, the pixel elements 7 to 9 are common. The fourth pad 6 is electrically connected by wire bonding.

  Next, after supplying the uncured and liquid sealing member 21 indicated by a two-dot chain line in FIG. 9A so that the pixel elements 7 to 9 and the bonding wires are filled, the sealing member 21 is heated and cured. Thus, the pixel elements 7 to 9 are sealed with the sealing member 21. Further, vertical and horizontal grooves 22 and 23 having a predetermined depth are formed in the sealing member 21 using a dicing cutter. The grooves 22 and 23 formed thereby are opened at both ends in the longitudinal direction and the surface of the sealing member 21, and sealing portions 21 a in which the pixels are individually sealed by the grooves 22 and 23 are arranged vertically and horizontally. Formed with. This state is representatively shown in FIG.

  Thereafter, as shown in FIG. 9C, the light reflecting layer 27 is formed over the entire surface of the sealing member 21. The light reflecting layer 27 can be formed by applying a white paint on the surface of the sealing member 21, or can be formed by vacuum-depositing Ag (silver) on the surface of the sealing member 21.

  Next, an uncured and liquid pad cover member 25 is supplied so as to fill the entire sealing member 21, and a part thereof is filled in the grooves 22 and 23. In this case, since the groove 23 has a V-shaped cross section, the back end of the groove 23 can be easily and reliably filled with the uncured and liquid pad cover member 25. Thereafter, the pad cover member 25 is cured by heating. Accordingly, the pad cover member 25 is disposed so as to cover the sealing member 21. This state is shown in FIG.

  Finally, using a dicing cutter, a part of the pad cover member 25 is cut off to form each light passage groove 26c. In this case, since the light passage grooves 26c extend straight in the same direction as the horizontal arrangement of the pixel regions E, a slit-like light passage is performed on the pad cover member 25 disposed on the sealing member 21 using a dicing cutter. By processing the groove 26c, it is not necessary to form individual light passage portions for each of the plurality of pixel regions E arranged in the lateral direction, and the light passage portions are once formed for the plurality of pixel regions E. It is preferable in that the processability of the light passage portion is good. Further, in the above cutting with the dicing cutter, the light reflecting layer 27 attached to the surface 21b of the sealing portion 21a is also cut at the same time by setting the cutting depth K. FIG. 7 shows a front view of the display 1 thus manufactured, and FIG. 8 shows an enlarged cross section of a part thereof.

  Since the configuration other than the points described above is the same as that of the first embodiment, the third embodiment can obtain the same operation as that of the first embodiment. Therefore, the display 1 of the third embodiment is suitable for arranging pixels with high density because it can suppress interference of light between adjacent pixel regions E, and has a printed circuit board (device board) 2. The colors of the first pad 3 to the fourth pad 6 are hardly visible. Moreover, the display 1 of the third embodiment is superior to the first embodiment in the following points.

  That is, the width H of the front surface 21b that forms the tip of the sealing part 21a farthest from the printed circuit board 2 is narrower than the width G of the back surface of the sealing part 21a that is in contact with the printed circuit board 2. The opening of the groove 23 between the sealing portions 21 a adjacent in the direction is wider than the back end of the groove 23. The pad cover member 25 is filled in the entire groove 23 so as to fill the opening of the groove 23. Therefore, the ratio of the pad cover member 25 occupying the display surface of the display 1 can be ensured large without being restricted by the size of the back end of the groove 23 of the sealing member 21. In other words, the ratio of the black pad cover member 25 to the light passage groove 26c forming the light passage portion is increased. Therefore, the contrast ratio of the display 1 is increased, and the visibility of the display 1 can be improved.

  Further, the display 1 according to the third embodiment includes a light reflecting layer 27 provided between the sealing member 21 and the pad cover member 25 so as to form a boundary therebetween. Therefore, the light emitted from the first pixel element 7 to the third pixel element 9 toward the boundary with the black pad cover member 25 is reflected by the pad cover member 25 without being blocked. Reflected by layer 27. Therefore, as a result, the amount of light emitted from the surface 21b of the sealing portion 21a and passing through the light passage groove 26c is increased, and light can be extracted efficiently.

  Moreover, as shown in FIG. 8, the surface of the pad cover member 25 protrudes in the light emission direction from the surface 21b of the sealing portion 21a. For this reason, the groove edge 25b of the pad cover member 25 facing the light passage groove 26b from above is caused to function as an eave and tries to enter the surface 21b of the sealing portion 21a obliquely from above as shown by the dotted line in FIG. Light (external light such as sunlight) can be blocked, and light reflected obliquely downward on the surface 21b is blocked by the groove edge 25c of the pad cover member 25 facing the light passage groove 26b from below. be able to. Therefore, the visibility of the display 1 can be improved.

  In addition, 3rd Embodiment can also be implemented, omitting the device which suppresses the reflection in the surface 21b of the sealing part 21a as mentioned above. In this case, the surface portion of the pad cover member 25 is removed by cutting or polishing from the state shown in FIG. 9D so that the surface 21b of the sealing portion 21a and the surface of the pad cover member 25 are flush with each other. Can be processed. In the third embodiment, the width of the light passage groove 26c is increased so that the light passage groove 26c (light passage portion) faces each part of the first pixel element 7 to the third pixel element 9. Can also be implemented.

  The fourth to sixth embodiments of the present invention will be described with reference to FIGS. Since these embodiments are the same as the third embodiment except for the items described below, the same configurations as those of the third embodiment are denoted by the same reference numerals as those of the third embodiment, and the description thereof is omitted.

  In the fourth embodiment shown in FIG. 10, the side surface of the groove 23 extending in the lateral direction of the display 1, in other words, the side surface of the sealing portion 21 a is formed in an arc shape. The other configuration is the same as that of the third embodiment including the configuration not shown in FIG. In the fifth embodiment shown in FIG. 11, a portion close to the printed circuit board 2 is perpendicular to the printed circuit board 2 in the side surface of the groove 23 extending in the lateral direction of the display 1, in other words, the side surface of the sealing portion 21 a. And the site | part close | similar to the surface 21b is formed in the diagonal surface. The other configuration is the same as that of the third embodiment including the configuration not shown in FIG. In the sixth embodiment shown in FIG. 12, the side surface of the groove 23 extending in the lateral direction of the display 1, in other words, the side surface of the sealing portion 21 a is formed in a step shape. The other configuration is the same as that of the third embodiment including the configuration not shown in FIG. Therefore, in these fourth to sixth embodiments, the same effect as that of the third embodiment can be obtained to solve the problem of the present invention.

  In addition, this invention is not restrict | limited to the said each embodiment. For example, in the third to sixth embodiments, the entire display 1 is arranged and used so that the slit-shaped light passage groove 26c extends in the lateral direction. However, instead of this, in indoor use, etc. It is also possible to arrange and use the entire display 1 such that the light passage groove 26c extends in the vertical direction. The light reflecting layer 27 described in the third embodiment can also be applied to the first embodiment.

  Although not shown, the present invention can be an LED display device made of a motherboard and a plurality of LED modules that are detachably mounted on one surface of the motherboard. In this case, any one of the high-definition LED displays described in the above embodiments is used as the LED module, and the bonding between the LED module and the mother board can be performed using cream solder or solder balls.

  Thereby, the enlargement of the LED display device can be realized. At the same time, in a lighting test performed in the manufacturing process of the LED display device after sealing and before the pad cover member is mounted, at least one failure of a pixel element included in the LED module is detected. When it turns out that a lighting failure has occurred as a cause, the entire LED display device is no longer disposed of as a lighting failure due to that, and only the LED module that has caused the lighting failure is replaced. The device can be repaired.

  In addition, in this implementation, on the motherboard, a gap is provided between the LED modules adjacent to each other in the direction in which one surface of the board spreads, and the size of the gap is determined by the mutual spacing between the adjacent sealing portions of the LED module, In other words, the width of the groove between the pixels is preferably the same. By doing in this way, it can control that the pitch of each pixel of an LED display device becomes uneven regardless of use of a plurality of LED modules.

1 is a schematic front view showing an LED display according to a first embodiment of the present invention. The front view which expands and shows a part of LED display of FIG. Sectional drawing which follows the F3-F3 line | wire in FIG. (A)-(C) is sectional drawing which showed the manufacturing process of the LED display of FIG. 1 in order. The partial front view which shows the state before a pad cover member is provided in the manufacture process of the LED display of FIG. The front view which expands and shows a part of LED display which concerns on 2nd Embodiment of this invention. The schematic front view which shows the LED display which concerns on 3rd Embodiment of this invention. Sectional drawing which follows the F8-F8 line | wire in FIG. (A)-(D) are sectional views showing the manufacturing process of the LED display of FIG. 7 in order. Sectional drawing equivalent to FIG. 8 which shows the LED display which concerns on 4th Embodiment of this invention. Sectional drawing equivalent to FIG. 8 which shows the LED display which concerns on 5th Embodiment of this invention. Sectional drawing equivalent to FIG. 8 which shows the LED display which concerns on 6th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Display, 2 ... Printed circuit board (device base), 2a ... Printed circuit board base, E ... Pixel region, 3 ... 1st pad, 4 ... 2nd pad, 5 ... 3rd pad, 6 ... 4th 7 ... 1st pixel element, 8 ... 2nd pixel element, 9 ... 3rd pixel element, 11-13 ... Bonding wire, 21 ... Sealing member, 21a ... Sealing part of sealing member, 22, 23 ... groove of sealing member, 25 ... pad cover member, 25 a ... groove filling part, 26 ... light passage hole (light passage part), 26 a, 26 b, 26 c ... light passage groove (light passage part), 27 ... Light reflection layer

Claims (6)

A device substrate having a plurality of pixel regions each provided with first to third pads;
A first pixel element comprising a semiconductor light emitting element mounted on the first pad and emitting red light when energized;
A second pixel element comprising a semiconductor light emitting element mounted on the second pad and emitting green light when energized;
A third pixel element which is mounted on the third pad and emits blue light when energized and which comprises a semiconductor light emitting element which forms a pixel together with the first and second pixel elements;
Each pad and each pixel element are sealed and provided on the device substrate, and each groove has a groove formed so as to individually surround each pixel region. A translucent sealing member that is closer to the device substrate than the tip of the pixel element;
A black pad cover member disposed on the sealing member so as to form a light passage portion through which light emitted from each pixel element passes to cover a part of each pixel region;
A display device comprising:   The display device according to claim 1, wherein an opening of the groove is wider than a back end of the groove, and the pad cover member is provided to fill the opening of the groove.   The display device according to claim 1, wherein the light passage portion is provided so as to face each part of the first to third pixel elements.   The inner end of the groove of the sealing member reaches the same height as the surface of the pad or between the surface and the surface of the base of the device substrate. The display device according to any one of the above.   The display device according to claim 4, wherein the pad cover member has a groove filling portion filled in a groove of the sealing member.   6. The display device according to claim 1, wherein a light reflecting layer is provided between the sealing member and the pad cover member.

Images