JP2017116887A - LED display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED display device capable of achieving 3D display, which allows an observer to feel a depth of the device more than a difference in the vertical arrangement of actual light sources, while having a simple configuration and being compact in a thickness direction.SOLUTION: The LED display device comprises a multilayer LED element substrate 20 and LED elements 11, 12, 13. Among flexible substrates 21, 22, 23 constituting the multilayer LED element substrate 20, the flexible substrates 21, 22 other than at least the flexible substrate 23 disposed at the outermost backside are transparent flexible substrates. The LED elements 11, 12, 13 are mounted on the flexible substrates 21, 22, 23 in such a manner that an arrangement pattern of the LED elements on each flexible substrate is similar to one another among the flexible substrates and that an arrangement pitch of the LED elements 11, 12, 13 gradually decreases from the outermost top side flexible substrate 21 to the backside flexible substrate 23.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an LED display device, and more particularly to an LED display device using a flexible substrate and capable of 3D display.

  Various LED display devices such as a dot matrix display device that configures and displays desired characters, symbols, or designs by selectively emitting LED elements are becoming widespread. For example, a display window is formed on the surface of a housing containing electronic components, an LED display panel in which a plurality of LED elements are arranged in a matrix on a wiring board is provided, and the display control device controls display of the LED elements of the LED display panel. An LED display device or the like configured to do so is known as a general mode (see Patent Document 1).

  In the recent widespread use of LED display devices, as an applied embodiment of LED display devices, it is possible to display characters, images, etc. in a manner that allows a viewer to feel a three-dimensional depth. Development of LED display devices capable of so-called 3D display is also progressing.

JP 2006-145682 A

  The present invention is a LED display device capable of 3D display, which is being developed in recent years, and has a simple structure and a compact configuration in the thickness direction, but gives the viewer a depth greater than the difference in the vertical arrangement of the actual light source. An object of the present invention is to provide an LED display device that can be felt by a viewer.

  In the LED display device using the LED element as a light source, the present inventors arrange the LED element separately on each layer of the multilayer LED element substrate, and change the actual arrangement of the LED element mounted as the light source according to the perspective principle. By adopting the applied arrangement, it has been found that an LED display device can be obtained that allows the viewer to feel the depth more than the difference in the vertical arrangement of the actual light source. Specifically, the present invention provides the following.

  (1) A multilayer LED element substrate in which a plurality of flexible substrates each having a metal wiring portion formed on a resin substrate are stacked, and an LED element mounted on each flexible substrate of the multilayer LED element substrate. The other flexible substrate excluding the flexible substrate arranged on the backmost side among the flexible substrates is a transparent flexible substrate, and the arrangement shape of the LED elements for each flexible substrate is Each of the flexible substrates is similar to each other, and the arrangement pitch of the LED elements gradually decreases from the flexible substrate on the outermost surface side to the flexible substrate on the rear surface side. An LED display device in which the LED element is mounted on the flexible substrate.

The invention of (1) is a display device that uses an LED element as a light source, and enables 3D display that allows the viewer to feel a depth greater than the actual physical arrangement based on the perspective principle. More specifically, this LED display device displays information such as characters and figures while allowing the viewer to feel a depth greater than the depth of the actual LED element arrangement within the limited small thickness of the LED display device. can do.
In the present specification, “flexible substrate” refers to a so-called flexible wiring substrate using a resin sheet having flexibility as a support substrate, and “transparent flexible substrate” refers to the above “flexible substrate”. In addition, the haze value of the support substrate is 8% or less. In addition, the “haze value” in this specification means a haze value (%) measured by a transparency test according to JISK7136.
In addition, the above “back surface side” means the opposite side of the LED display device when the display surface side of the LED display device is the front surface side, that is, the non-display surface side. For example, in the LED display device 1 of FIG. 2, among the flexible substrates 21 to 23 that constitute the multilayer LED element substrate 20, the flexible substrate 23 is a “backmost side” flexible substrate.

  (2) Of the flexible substrates, the reduction ratio of the arrangement pitch between the two flexible substrates adjacent in the direction perpendicular to the display surface of the LED display device is the same ratio (1). The LED display device described.

  According to the invention of (2), the above-described “depth can be felt” effect relating to the visual information displayed in the LED display device of (1) can be expressed with higher quality based on perspective. it can.

(3) All the flexible substrates are transparent flexible substrates,
When the surface coverage by the metal wiring part of all the flexible substrates is 2% or more and 10% or less, the substrate aperture ratio of the multilayer LED element substrate is 80% or more (1) or ( LED display device as described in 2).

  In the invention of (3), the LED display device according to either (1) or (2) may be a see-through type LED display device that can visually recognize visual information disposed on the back side of the display screen. it can.

  (4) The LED display device according to any one of (1) to (3), wherein a total thickness of the multilayer LED element substrate is 15 mm or less.

  According to the invention of (4), in the LED display devices of (1) to (3), the characteristic visual effect in the present application that “the viewer can visually feel a three-dimensional depth” It can be realized by a display device with a small depth.

  According to the present invention, the LED display device capable of 3D display, which has been developed in recent years, has a simple and compact configuration in the thickness direction, and allows the viewer more than the difference in the vertical arrangement of the actual light source. An LED display device that can make a viewer feel the depth can be provided.

It is a top view which shows typically the mounting aspect of the LED element in the LED display apparatus of this invention. It is sectional drawing which shows typically the laminated constitution of the LED display apparatus of this invention. It is a perspective view which shows typically embodiment of the LED display apparatus of this invention.

  Hereinafter, embodiments of the LED display device of the present invention will be sequentially described. The present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the object of the present invention.

<LED display device>
The LED display device of the present invention can display visual information such as letters and figures using an LED element as a light source in a manner that “the viewer can visually feel a three-dimensional depth”. It is a display device. Mainly, it is assumed to be used both for practical purposes related to information transmission and for decorative purposes in places and spaces due to excellent aesthetics.

  The LED display device 1 of the present invention schematically showing the outline of the embodiment in FIG. 3 has a number of LED elements on a support substrate made of a flexible resin film or the like, with a unique arrangement that will be described in detail below. The multilayer LED element substrate 20 formed by laminating the flexible substrates 21, 22, and 23 on which the mountable metal wiring portions are formed, and the flexible substrates 21, 22, and 23 constituting the multilayer LED element substrate 20 will be described below. It is an LED display apparatus comprised including the LED element mounted by the predetermined | prescribed arrangement | positioning.

  As shown in FIG. 2, in the LED display device 1, the LED elements 11, 12, and 13 are distributed and arranged on the respective flexible substrates 21, 22, and 23 constituting the multilayer LED element substrate 20. And the arrangement | positioning shape of LED element 11, 12, 13 for each flexible substrate 21,22,23 is mutual between each said flexible substrate 21,22,23, as shown in FIG.1, FIG.2, FIG.3. The layout should be similar to. Further, the arrangement pitches P1, P2, and P3 of the LED elements 11, 12, and 13 are gradually decreased from the outermost surface side flexible substrate 21 toward the rear surface side flexible substrate 23. That is, P1> P2> P3. Moreover, it is more preferable that the reduction ratios of the arrangement pitches of the LED elements 11, 12, and 13 are all equal, that is, P2 / P1 = P3 / P2.

  According to the specific three-dimensional arrangement of the LED elements as described above, as shown in FIG. 3, the viewer has a depth greater than the depth defined by the positional relationship of the actual light sources (LED elements) according to the perspective principle. , You can feel the displayed characters and figures. Note that the arrangement of “similar shapes to each other” does not strictly require that all the LED elements are arranged in a similar shape, but most of the display area (90% (Preferably 95% or more) such an arrangement enables display of information such as the above-mentioned figures and characters that “the viewer can visually sense a three-dimensional depth” Any arrangement may be used.

  The number of the flexible substrates constituting the multilayer LED element substrate 20 may be two or more and is not limited to a specific number, but is preferably two or more and preferably about ten or less. In the following, an LED display device including the multilayer LED element substrate 20 composed of three flexible substrates will be described in detail as a representative embodiment for the sake of simplicity.

  When the flexible substrates 21, 22, and 23 are sequentially laminated from the information display surface side of the LED display device 1, at least the other flexible substrate closer to the surface side excluding the flexible substrate 23 disposed on the backmost side 21 and 22 are transparent flexible substrates. The transparency of the flexible substrate 23 arranged on the back side is not particularly limited, but by making all the flexible substrates including the flexible substrate 23 arranged on the back side into a transparent flexible substrate, LED display The device 1 can also be a see-through display device.

  The size of the LED display device 1 is not particularly limited. However, since a substrate made of a flexible substrate is used as a substrate material, the degree of freedom of size processing of the substrate is high, and therefore, it can be preferably used for a large-sized LED display device that is assumed to be used outdoors.

[Multilayer LED element substrate]
As shown in FIGS. 1 and 2, the multilayer LED element substrate 20 is a multilayer circuit substrate configured by laminating flexible substrates 21, 22, and 23. As shown in FIG. 2, in the multilayer LED element substrate 20, flexible substrates 21, 22, and 23 are preferably arranged in parallel with each other in a normal embodiment. The distance between the back surface of each flexible substrate 21, 22, 23 and the LED elements 11, 12, 13 depends on the design design of the display target such as how much the depth of the 3D display to be displayed is set. Although it may be adjusted as appropriate, as a general example, it is assumed that the interval is about 2 mm or more and 40 mm or less. An appropriate distance between the substrates can be maintained by fixing each panel at a predetermined position of an outer frame such as a metal frame, but a transparent resin sealing material having an appropriate thickness between the panels. May be interposed. The lower limit of 2 mm is a value that takes into account that the thickness is larger than the thickness of a general LED element, and the upper limit of 40 mm is larger than the arrangement pitch of a general LED element. It is a numerical value that takes into account that it should be small.

  The thickness of the multilayer LED element substrate 20 is preferably 6 mm or more and 15 mm or less in the case of the present embodiment including, for example, three flexible substrates, and particularly thinned by taking advantage of the flexibility of processing of the flexible substrate. From this viewpoint, it is more preferably 10 mm or less.

(Flexible substrate)
As the flexible substrates 21, 22, and 23, a metal wiring portion (not shown) made of copper foil or the like can be mounted on the surface of a support substrate made of a transparent resin film or the like so that LED elements can be mounted in a predetermined arrangement form of the present application As long as it is formed, a conventionally known flexible substrate can be used as appropriate. However, as described above, the support substrate 231 used for the flexible substrate 23 arranged on the backmost side is not necessarily transparent. In addition, the metal wiring portion has a function of conducting electricity between the LED elements, supplying a necessary current, and supplying electricity, and also exhibits an effect as a heat radiating portion in the flexible substrates 21, 22, and 23.

  The other flexible substrates 21 and 22 other than the flexible substrate 23 arranged on the backmost side are required to be circuit boards having “transparency” of a certain level or more. In the present specification, the flexible substrate “has transparency” means that the haze value of the support substrate made of the above resin film or the like in the visible light region is 8% or less, preferably 4% or less, more preferably. It shall be said that it is 3% or less.

  Preferred examples of the resin used as the support substrates 211, 221, and 231 of the flexible substrates 21, 22, and 23 are polyimide (PI) and polyethylene from the viewpoint that it is preferable to have a certain level of heat resistance or insulation. Examples thereof include naphthalate (PEN), polyethylene terephthalate (PET), amorphous polyarylate, polysulfone, polyethersulfone, polyetherimide, fluororesin, and liquid crystal polymer. Among these, polyethylene naphthalate (PEN) whose heat resistance and dimensional stability are improved by performing a heat resistance improvement treatment such as an annealing treatment can be particularly preferably used. The thicknesses of the support substrates 211, 221, and 231 of the flexible substrates 21, 22, and 23 are not particularly limited, but are preferably approximately 50 μm or more and 200 μm or less. Also, the thickness is preferably within the above-mentioned thickness range from the viewpoint of maintaining good productivity when manufacturing by the roll-to-roll method.

  Examples of the metal constituting the metal wiring part include metal foils such as aluminum, gold, silver, and copper. In order to maximize the see-through function of the flexible substrate, it is conceivable to form the metal wiring portion with a transparent electrode. However, the transparent electrode is a copper that has been widely used in the past in terms of reliability and manufacturing cost in accurately applying a stable and uniform voltage to the entire circuit disposed on the entire surface of the LED element substrate. Inferior to metal wiring such as foil. In order to promote heat dissipation from the substrate, it is preferable that the metal wiring has high thermal conductivity. In this respect, the copper foil is clearly superior. The tendency of the metal foil to be dominant becomes more remarkable as the screen size of the display surface increases.

  When the LED display device of the present invention is used as a see-through type LED display device, the flexible substrates 21, 22, and 23 that constitute each layer of the multilayer LED element substrate 20 that constitutes the LED display device depend on the metal wiring portion thereof. The surface coverage is preferably 2% or more and 10% or less. Since the surface coverage by the metal wiring portion is 2% or more and 10% or less, the substrate opening ratio of the multilayer LED element substrate 20 is set to 85% or more and 90% or more, and a sufficient see-through function is provided in the LED display device. Can be provided. The “substrate aperture ratio of the multilayer LED element substrate” refers to a ratio defined as an area ratio of a portion of the surface of the substrate aperture ratio of the multilayer LED element substrate where the metal wiring portion does not exist in plan view. Say it.

  In addition, an insulating protective film is laminated | stacked as needed in the other part except the part which needs the electrical connection on the surface of the metal wiring part and the support substrate 211,221,231. The insulating protective film is required to be capable of maintaining the transparency of the flexible substrates 21 and 22 as with the support substrates 211 and 221. The haze value and other optical characteristics required for the insulating protective film are the same as those required for the support substrates 211 and 221, and the haze value is 8% or less, preferably 4% or less.

  The LED elements 11, 12, and 13 that are mounted on the flexible substrates 21, 22, and 23 as the light source are not particularly limited, but a surface-mounted chip LED element can be preferably used. A chip-type LED element is a P-type semiconductor and an N-type semiconductor bonded to a fine packing made of resin, etc., in which electrodes (anode and cathode) and a reflector for mounting directly on a circuit are integrated. It is an element having a built-in diode-type light-emitting chip as a light emitter. Also, LED elements having various emission colors can be freely arranged in the horizontal direction and the vertical direction according to the design design of the display. For example, by mounting 3in1 type LED elements capable of multicolor display in each layer, 3D display of various colors, patterns, and brightness is possible in the LED display device 1.

<Embodiment example of LED display device>
For example, an embodiment as shown in FIG. 1 is assumed for the LED display device 1. In other words, a display capable of transmitting specific character information is performed, and at the same time, the display is made into a three-dimensional display rich in aesthetics, so that it is installed as a display device having both practicality and decoration.

DESCRIPTION OF SYMBOLS 1 LED display device 11, 12, 13 LED element 20 Multilayer LED element substrate 21, 22, 23 Flexible substrate 221, 221, 231 Support substrate

Claims (4)

A multilayer LED element substrate in which a flexible substrate in which a metal wiring part is formed on a resin substrate is laminated, and
LED elements mounted on the flexible substrates of the multilayer LED element substrate,
Among the flexible substrates, at least the other flexible substrate excluding the flexible substrate disposed on the backmost side is a transparent flexible substrate,
The arrangement shape of the LED elements for each flexible substrate is similar to each other between the flexible substrates, and the flexible substrate on the outermost surface side is directed to the flexible substrate on the back side, The LED display device in which the LED elements are mounted on the flexible substrates so that the arrangement pitch of the LED elements is gradually reduced.   2. The LED according to claim 1, wherein among the flexible substrates, the reduction ratio of the arrangement pitch between the two flexible substrates adjacent to each other in the direction perpendicular to the display surface of the LED display device is an equal ratio. Display device. All the flexible substrates are transparent flexible substrates,
The surface area coverage by the metal wiring part of all the flexible substrates is 2% or more and 10% or less, so that the substrate opening ratio of the multilayer LED element substrate is 80% or more. LED display device described in 1.   The LED display device according to claim 1, wherein a total thickness of the multilayer LED element substrate is 15 mm or less.

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