TWI832429B - Flexible transparent display and flexible circuit board thereof - Google Patents

Abstract

A flexible transparent display and a flexible circuit board thereof are provided. The flexible circuit board includes a flexible transparent substrate and a first circuit layer. The flexible transparent substrate has a first surface and a second surface opposite to the first surface. The first circuit layer is disposed on the flexible transparent substrate and allows a current of at least greater than 1 × 10 ^-3mA to flow therein. The first circuit layer includes a plurality of first signal lines. Any adjacent two of the first signal lines has a predetermined spacing therebetween, and the ratio of a diameter of each first signal line to the predetermined spacing is 1:5 to 1:30. Therefore, the display can has a reduced visibility of lines and an increased display effect, and can adapt to different three-dimensional shapes.

Description

Flexible transparent display and its flexible circuit board

The invention relates to a display screen, in particular to a flexible transparent display screen and a flexible circuit board thereof.

With the advancement of display technology, transparent displays have been developed. In addition to displaying images for viewing, a transparent display can also allow viewers to see the scenery behind them through the transparent display. Therefore, transparent displays are widely used. In response to the diversification trend in the display field, the development of light-emitting display technology using flexible substrates with passive point light-emitting sources or active point light-emitting sources is becoming increasingly important. The passive point light source is, for example, a light emitting diode (LED), and the active point light source is, for example, an organic light-emitting diode (OLED).

In the production of a transparent display, multiple light-emitting sources can be arranged in an array on a substrate, and one or more driving chips (ICs) can be placed outside or inside the multiple light-emitting sources. In order to allow multiple light-emitting sources to be illuminated and have required brightness, laying out circuits on the substrate is often quite complex, which is clearly visible in the display screen and affects the viewer's visual experience to a certain extent. On the other hand, in order to meet the display effects required in various applications, the production of the configuration wires of these LED components must have good design changeability and can be quickly completed. In view of the above technical problems, the present invention hopes to provide solutions.

The technical problem to be solved by the present invention is to provide a flexible transparent display screen and its flexible circuit board in view of the shortcomings of the existing technology.

In order to solve the above technical problems, one of the technical solutions adopted by the present invention is to provide a flexible circuit board, which includes a flexible transparent substrate and a first circuit layer. The flexible transparent substrate has an opposite first surface and a second surface. The first circuit layer is formed on the first surface and allows a current of at least greater than 1 × 10 ^-3 mA to pass through. The first circuit layer includes a plurality of first signal lines. There is a predetermined spacing between two adjacent first signal lines, and the diameter of each first signal line is consistent with the predetermined spacing. The ratio is 1:5 to 1:30.

In an embodiment of the present invention, the diameter of each first signal line is 0.005 mm to 0.2 mm.

In an embodiment of the present invention, the coverage rate of the first circuit layer on the first surface is 65% to 90%.

In an embodiment of the present invention, the flexible circuit board has a plurality of specific areas, and the flexible circuit board further includes a second circuit layer formed on the first surface or the first surface of the flexible transparent substrate. on the second surface. The second circuit layer defines a conductive pad group and at least one second signal line connected to the conductive pad group in each of the specific areas.

In an embodiment of the present invention, several of the first signal lines intersect with several other first signal lines to form a plurality of grid structures, and a plurality of the specific areas are located in a plurality of the grids. between structures, and the second circuit layer is formed on the first surface of the flexible transparent substrate in a manner spanning a plurality of the grid structures. In each of the specific areas, the conductive pad group includes a plurality of conductive pads, one of the conductive pads is connected to one of the adjacent grid structures, and the remaining conductive pads are connected to at least One of the second signal lines is connected.

In an embodiment of the present invention, the flexible circuit board further includes a third circuit layer, and the third circuit layer is formed on the second surface of the flexible transparent substrate. The third circuit layer includes a plurality of third signal lines arranged at intervals, and the plurality of third signal lines correspond to several of the first signal lines up and down.

In an embodiment of the present invention, several of the first signal lines intersect with several other first signal lines to form a plurality of upper grid structures, and a plurality of the specific areas are located on a plurality of the upper layers. between the grid structures, and the second circuit layer is formed on the first surface of the flexible transparent substrate in a manner that avoids the locations of multiple upper grid structures. In each of the specific areas, the conductive pad group includes a plurality of conductive pads, two of the conductive pads are respectively connected to two adjacent grid structures, and the remaining conductive pads Connected to at least one second signal line.

In an embodiment of the present invention, the flexible circuit board further includes a fourth circuit layer, the fourth circuit layer is formed on the second surface of the flexible transparent substrate and is connected with the fourth circuit layer. layer electrical connection. The fourth circuit layer includes a plurality of fourth signal lines arranged at intervals. There is another predetermined spacing between two adjacent fourth signal lines, and the diameter of each fourth signal line is the same as that of the fourth signal line. The ratio of another predetermined spacing is 1:5 to 1:30.

In an embodiment of the present invention, the diameter of each fourth signal line is 0.005 mm to 0.2 mm.

In an embodiment of the present invention, the coverage rate of the fourth circuit layer on the second surface is 65% to 90%.

In an embodiment of the present invention, a plurality of the fourth signal lines intersect with another plurality of the fourth signal lines to form a plurality of lower grid structures, and the plurality of lower grid structures are connected to a plurality of lower grid structures. The grid structure in the upper layer corresponds to the top and bottom.

In an embodiment of the present invention, several of the first signal lines intersect with several other first signal lines to form a plurality of grid structures, and the second circuit layer is formed on the flexible transparent on the second surface of the substrate. In each of the specific areas, the conductive pad group includes a plurality of conductive pads, one of the conductive pads is electrically connected to one of the corresponding grid structures, and the remaining conductive pads are connected to at least One of the second signal lines is connected.

In an embodiment of the present invention, the flexible circuit board further includes a third circuit layer. The third circuit layer is formed on the first circuit layer through an insulating layer and is connected to the second circuit layer. Electrical connection. The third circuit layer includes a plurality of third signal lines arranged at intervals, and the plurality of third signal lines correspond to several of the first signal lines up and down.

In order to solve the above technical problems, another technical solution adopted by the present invention is to provide a flexible transparent display screen, which includes a flexible circuit board with the above structure and a plurality of light-emitting units, and a plurality of the light-emitting units are arranged on the on a flexible circuit board.

In an embodiment of the present invention, the flexible transparent display further includes one or more control units, and the control units are electrically connected to the flexible circuit board.

In an embodiment of the present invention, each of the light-emitting units has a built-in control unit.

One of the beneficial effects of the present invention is that the flexible transparent display screen and its flexible circuit board of the present invention adopt "the first circuit layer is formed on the flexible transparent substrate and allows a current of at least greater than 1 × 10 ^-3 mA to pass through" and "The first circuit layer includes a plurality of first signal lines. There is a predetermined spacing between two adjacent first signal lines, and the ratio of the wire diameter of each first signal line to the predetermined spacing is 1:5 to 1 :30” technical features can significantly reduce the visibility of the lines in the display screen, increase the transparency of the display screen, and greatly improve the display effect.

In order to further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are only for reference and illustration and are not used to limit the present invention.

The following is a specific example to illustrate the implementation of the "flexible transparent display screen and its flexible circuit board" disclosed in the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only simple schematic illustrations and are not depictions based on actual dimensions, as is stated in advance. The following embodiments will further describe the relevant technical content of the present invention in detail, but the disclosed content is not intended to limit the scope of the present invention. In addition, the term "or" used in this article shall include any one or combination of more of the associated listed items depending on the actual situation. In addition, the prepositions "first to fourth" used in this article are only used to distinguish similar components and do not have a sequential nature.

[First Embodiment]

Referring to FIGS. 1 to 3 , and as shown in FIGS. 4 to 6 , a first embodiment of the present invention provides a flexible circuit board Z, which mainly includes a flexible transparent substrate 1 and a first circuit layer 2 . The flexible transparent substrate 1 has an opposite first surface 101 and a second surface 102. The first surface 101 is, for example, an upper surface, and the second surface 102 is, for example, a lower surface. The first circuit layer 2 is formed on the first surface 101 of the flexible transparent substrate 1, and the current allowed by the first circuit layer 2 is at least greater than 1 × 10 ^-3 mA; the first circuit layer 2 includes a plurality of first signal lines 21 , which can be used as a power connection line to transmit electrical signals (current signals or voltage signals). It is worth mentioning that there is a predetermined distance D1 between two adjacent first signal lines 21, and the ratio of the wire diameter W of each first signal line 21 to the predetermined distance D1 is 1:5 to 1:30. .

The flexible circuit board Z of the present invention can be applied to a transparent display screen, and through the design of the first circuit layer 2, it can significantly reduce the visibility of the circuit in the display screen, increase the transparency of the display screen, and greatly improve the display effect. In addition, with the presence of the flexible transparent substrate 1, the display screen can adapt to different three-dimensional shapes and has a wider range of applications, such as but not limited to shop windows, building exterior walls, automobiles, public transportation, etc. The flexible transparent substrate 1 can be a plastic substrate with high transmittance to visible light (greater than 80%), and its materials can include but are not limited to polyester (such as polyethylene terephthalate), polyimide (Polyimide), polycarbonate (Polycarbonate) and cyclic olefin copolymer (Cyclic olefin copolymer).

In this embodiment, the coverage rate of the first circuit layer 2 on the first surface 101 of the flexible transparent substrate 1 is in the range of 65% to 90%, and the wire diameter W of each first signal line 21 is 0.005 mm to 0.2 mm. In addition, several first signal lines 21 extend along the first direction X, and several first signal lines 21 extend along the second direction Y; the first direction X and the second direction Y can be horizontal respectively. direction and vertical direction, as shown in Figure 1, or the first direction X and the second direction Y can be two different tilt directions, as shown in Figure 6. Furthermore, the first signal lines 21 extending along the first direction Multiple specific areas A, that is, each specific area A is located in the space vacated between two adjacent grid structures M1; as a flexible circuit board Z of a transparent display screen, the specific area A can be a light-emitting pixel area, However, the present invention is not limited to this.

In actual application, a first interface layer (not shown in the figure) can be formed on the first surface 101 of the flexible transparent substrate 1 first, and then the first circuit layer 2 is formed through the first interface layer, as shown in Figure 4 and Figure As shown in 5, the first interface layer and the first circuit layer 2 have the same pattern. The material of the first circuit layer 2 can be a metal with good conductivity, such as gold, silver, copper or their alloy. The material of the first interface layer can be gold, silver, copper, aluminum, tin, titanium, nickel, chromium, Palladium or any alloy of these metals, the first interface layer can be used as an auxiliary layer to form the first circuit layer 2, that is, in the presence of the first interface layer, the first circuit layer 2 can be formed more easily and firmly attached to the flexible on the transparent substrate 1. In an embodiment not shown, the first interface layer may not be assisted when forming the first circuit layer 2 .

As shown in FIG. 1 and FIG. 3 to FIG. 5 , the flexible circuit board Z of the present invention may further include a second circuit layer 3 to provide electrical contacts and signal connection lines. The second circuit layer 3 is formed on the first surface 101 of the flexible transparent substrate 1 across a plurality of grid structures M1 to define a conductive pad group 31 and at least one conductive pad group in each specific area A. The second signal line 32 is connected to 31; the wire diameter of the second signal wire 32 is the same as or different from the wire diameter W of the first signal line 21. In addition, the second circuit layer 3 (second signal lines 32) can be separated from the plurality of mesh structures M1 (first signal lines 21) by an insulating layer 9a and maintain electrical insulation. In each specific area A, the conductive pad group 31 includes a plurality of conductive pads 31a, 31b, 31c, 31d, which can be used as a signal transmission interface and/or a connection interface for electronic components (such as light-emitting components/components). Secondly, The signal line 32 can be used as a signal connection line for transmitting control signals. During use, one of the conductive pads 31a is connected to one of the adjacent grid structures M1, and the remaining conductive pads 31b, 31c, and 31d are connected to at least one second signal line 32.

In actual application, the insulating layer 9a can be formed first to cover the plurality of mesh structures M1, and then a second interface layer (not shown in the figure) is formed on the first surface 101 of the flexible transparent substrate 1, wherein the second interface layer The insulating layer 9a is separated from the plurality of mesh structures M1, and then the second circuit layer 3 is formed through a second interface layer. The second interface layer and the second circuit layer 3 have the same pattern. The material of the second circuit layer 3 can be a metal with good conductivity, such as gold, silver, copper or their alloy. The material of the second interface layer can be gold, silver, copper, aluminum, tin, titanium, nickel, chromium, Palladium or any alloy of these metals, the second interface layer can be used as an auxiliary layer to form the second circuit layer 3, that is, in the presence of the second interface layer, the second circuit layer 3 can be formed more easily and firmly attached to the flexible on the transparent substrate 1. In an embodiment not shown, the second interface layer may not be assisted when forming the second circuit layer 3 .

As shown in FIG. 2 and FIG. 3 to FIG. 5 , in order to provide more signal connection lines, the flexible circuit board Z of the present invention may further include a third circuit layer 4 . The third circuit layer 4 is formed on the second surface 102 of the flexible transparent substrate 1. The third circuit layer 4 can be electrically connected to the second circuit layer 3 through one or more via holes (not shown in the figure), but is not limited to this. The third circuit layer 4 includes a plurality of third signal lines 41 arranged at intervals, the extending directions of which are perpendicular to the extending directions of the second signal lines 32 . The diameters of the third signal lines 41 are the same as or different from those of the first signal lines 21 . Wire diameter W. It is worth mentioning that the plurality of third signal lines 41 and the plurality of first signal lines 21 extending along the first direction Above the several first signal lines 21, in this way, the visibility of the first signal lines 21 in the display screen can be reduced, and the overall transparency will not be affected even when the circuit complexity increases.

In actual application, a third interface layer (not shown in the figure) can be formed on the second surface 102 of the flexible transparent substrate 1 first, and then the third circuit layer 4 is formed through the third interface layer. The third interface layer and The third circuit layer 4 has the same pattern. The material of the third circuit layer 4 can be a metal with good conductivity, such as gold, silver, copper or their alloy. The material of the third interface layer can be gold, silver, copper, aluminum, tin, titanium, nickel, chromium, Palladium or any alloy of these metals, the third interface layer can be used as an auxiliary layer to form the third circuit layer 4, that is, in the presence of the third interface layer, the third circuit layer 4 can be formed more easily and firmly attached to the flexible on the transparent substrate 1. The above descriptions are only feasible implementations and are not intended to limit the present invention. In an embodiment not shown, the third interface layer may not be assisted when forming the third circuit layer 4 .

Referring again to Figure 1 and Figures 3 to 5 , and as shown in Figures 7 to 8 , a first embodiment of the present invention also provides a flexible transparent display D, which mainly includes the above-mentioned flexible transparent substrate 1 and a plurality of light-emitting units. 6 and one or more control units 7. The plurality of light-emitting units 6 are respectively disposed in multiple specific areas A of the flexible transparent substrate 1, and each light-emitting unit 6 is electrically connected and fixed to the conductive element in the specific area A. On the pad set 31, the control unit 7 is electrically connected to the flexible transparent substrate 1, and can control the luminous effects of the plurality of light-emitting units 6 through the flexible transparent substrate 1. In this embodiment, the plurality of light-emitting units 6 are evenly distributed on the first surface 101 of the flexible transparent substrate 1 in an array, and the minimum separation distance D2 (horizontal distance) between the plurality of light-emitting units 6 is relatively small. It is best to be in the range of 2 mm to 3 mm. This allows the display to have better contrast and clarity, especially when viewed from a certain distance.

As shown in FIG. 7 , the light-emitting unit 6 may be a light-emitting diode package structure, which includes a red light-emitting element 61 , a green light-emitting element 62 and a blue light-emitting element 63 (using an RGB configuration). The red light-emitting element 61 may be a red light-emitting diode chip, or the red light-emitting element 61 may include a blue light-emitting diode chip and a wavelength conversion layer formed on the blue light-emitting diode chip, wherein the wavelength conversion layer The layer can have red phosphor. The green light-emitting element 62 may be a green light-emitting diode chip, or the green light-emitting element 62 may include a blue light-emitting diode chip and a wavelength conversion layer formed on the blue light-emitting diode chip, wherein the wavelength conversion layer The layer can have green phosphor. The blue light-emitting element 63 may be a blue light-emitting diode chip. In addition, the control unit 7 may be a drive control chip, but is not limited thereto. It should be noted that the number, color, arrangement, etc. of the light-emitting elements can be adjusted and designed according to actual needs, and the present invention is not limited to the above examples. In some embodiments, the light emitting unit 6 may adopt an RGBW configuration. In some embodiments, the light emitting unit 6 may be a single light emitting diode chip.

In actual application, as shown in Figures 3, 4, 7, and 8, the light-emitting unit 6 may have four pins L1, L2, L3, and L4, and the conductive pad group 31 may include four conductive pads 31a, 31b, 31c, 31d, and the four pins L1, L2, L3, and L4 can be connected to the four conductive pads 31a, 31b, 31c, and 31d through conductive bumps B (bumpers) respectively. Furthermore, the pin L1 is a common pin of the red light-emitting element 61, the green light-emitting element 62 and the blue light-emitting element 63. The corresponding conductive pad 31a is connected to one of the adjacent grid structures M1. A reference signal (such as a reference voltage) is provided to the red light-emitting element 61 , the green light-emitting element 62 and the blue light-emitting element 63 . The pins L2, L3, and L4 are respectively the lead-out pins of the red light-emitting element 61, the green light-emitting element 62, and the blue light-emitting element 63. The corresponding conductive pads 31b, 31c, and 31d are respectively connected to the three second signal lines 32. , used to provide control electrical signals (such as control voltage) to the red light-emitting element 61 , the green light-emitting element 62 and the blue light-emitting element 63 . It should be noted that the number of pins L1, L2, L3, and L4 of the light-emitting unit 6 and the number of the conductive pads 31a, 31b, 31c, and 31d can be adjusted and designed according to actual needs. The present invention does not use the above-mentioned methods. Examples are limited.

[Second Embodiment]

Referring to FIGS. 9 and 10 , and as shown in FIGS. 11 to 14 , a second embodiment of the present invention provides a flexible circuit board Z, which mainly includes a flexible transparent substrate 1 and a first circuit layer 2 . The flexible transparent substrate 1 has an opposite first surface 101 and a second surface 102. The first surface 101 is, for example, an upper surface, and the second surface 102 is, for example, a lower surface. The first circuit layer 2 is formed on the first surface 101 of the flexible transparent substrate 1, and the current allowed by the first circuit layer 2 is at least greater than 1 × 10 ^-3 mA; the first circuit layer 2 includes a plurality of first signal lines 21 , which can be used as a power connection line to transmit electrical signals (current signals or voltage signals). It is worth mentioning that there is a predetermined distance D1 between two adjacent first signal lines 21, and the ratio of the wire diameter W of each first signal line 21 to the predetermined distance D1 is 1:5 to 1:30. . The difference between this embodiment and the first embodiment is that the connection interface of the electronic component (such as a light-emitting element/component) is arranged on the second surface 102 of the flexible transparent substrate 1; that is to say, the flexible circuit board Z can It further includes a second circuit layer 3 , and the second circuit layer 3 is formed on the second surface 102 of the flexible transparent substrate 1 .

In this embodiment, the flexible transparent substrate 1 can be a plastic substrate with high transmittance to visible light (greater than 80%), and its material can include but is not limited to polyester (such as polyethylene terephthalate, Polyethylene terephthalate). ), polyimide, polycarbonate and cyclic olefin copolymer. The coverage rate of the first circuit layer 2 on the first surface 101 of the flexible transparent substrate 1 is in the range of 65% to 90%, and the wire diameter W of each first signal line 21 is in the range of 0.005 mm to 0.2 mm. within. In addition, several first signal lines 21 extend along the first direction X, and several first signal lines 21 extend along the second direction Y, and several first signal lines 21 extend along the first direction X. The lines 21 intersect with several first signal lines 21 extending along the second direction Y to form a plurality of grid structures M1; the first direction X and the second direction Y can be horizontal and vertical directions respectively, as shown in 10. Or the first direction X and the second direction Y can be two different tilt directions, as shown in Figure 14.

In addition, as shown in Figures 9, 11 and 13, the flexible transparent substrate 1 has a plurality of specific areas (such as light-emitting pixel areas), and the second circuit layer 3 defines a conductive pad group 31 and At least one second signal line 32 is connected to the conductive pad group 31; the diameter of the second signal line 32 is the same as or different from the diameter W of the first signal line 21. In each specific area A, the conductive pad group 31 includes a plurality of conductive pads 31a, 31b, 31c, and 31d, and the second signal line 32 can be used as a signal connection line for transmitting control signals. When in use, one of the conductive pads 31a, 31b, 31c, and 31d can be electrically connected to one of the corresponding grid structures M1 through a via hole (not shown in the figure), and the remaining conductive pads 31a, 31b, 31c, and 31d Connected to at least one second signal line 32 .

In this embodiment, in order to provide more signal connection lines, the flexible circuit board Z may further include a third circuit layer 4 . The third circuit layer 4 is formed on the first surface 101 of the flexible transparent substrate 1 across a plurality of grid structures M1. The third circuit layer 4 can be connected to the second circuit layer through one or more via holes (not shown in the figure). The circuit layer 3 is electrically connected, but is not limited to this. The third circuit layer 4 includes a plurality of third signal lines 41 arranged at intervals, the extending directions of which are perpendicular to the extending directions of the second signal lines 32 . The diameters of the third signal lines 41 are the same as or different from those of the first signal lines 21 . Wire diameter.

Furthermore, the third circuit layer 4 (third signal line 41) can be separated from and maintained electrically insulated from the plurality of mesh structures M1 (first signal lines 21) by an insulating layer 9b, in which each third The signal line 41 is electrically connected to a corresponding second signal line 32 . It is worth mentioning that the plurality of third signal lines 41 and the plurality of first signal lines 21 extending along the first direction Above the several first signal lines 21, in this way, the visibility of the first signal lines 21 in the display screen can be reduced, and the overall transparency will not be affected even when the circuit complexity increases.

As for the method of forming the first circuit layer 2, the second circuit layer 3 and the third circuit layer 4, reference can be made to the description in the first embodiment, so no further description will be given here.

Referring again to Figures 9 and 11 to 13, and as shown in Figures 7 and 8, a second embodiment of the present invention also provides a flexible transparent display D, which mainly includes the above-mentioned flexible transparent substrate 1 and a plurality of light-emitting units. 6 and one or more control units 7. The plurality of light-emitting units 6 are respectively disposed in multiple specific areas A of the flexible transparent substrate 1, and each light-emitting unit 6 is electrically connected and fixed to the conductive element in the specific area A. On the pad set 31, the control unit 7 is electrically connected to the flexible transparent substrate 1, and can control the luminous effects of the plurality of light-emitting units 6 through the flexible transparent substrate 1. In this embodiment, the plurality of light-emitting units 6 are evenly distributed on the first surface 101 of the flexible transparent substrate 1 in an array, and the minimum separation distance D2 (horizontal distance) between the plurality of light-emitting units 6 is relatively small. It is best to be in the range of 2 mm to 3 mm. This allows the display to have better contrast and clarity, especially when viewed from a certain distance.

As shown in FIG. 7 , the light-emitting unit 6 may be a light-emitting diode package structure, which includes a red light-emitting element 61 , a green light-emitting element 62 and a blue light-emitting element 63 (using an RGB configuration). The red light-emitting element 61 may be a red light-emitting diode chip, or the red light-emitting element 61 may include a blue light-emitting diode chip and a wavelength conversion layer formed on the blue light-emitting diode chip, wherein the wavelength conversion layer The layer can have red phosphor. The green light-emitting element 62 may be a green light-emitting diode chip, or the green light-emitting element 62 may include a blue light-emitting diode chip and a wavelength conversion layer formed on the blue light-emitting diode chip, wherein the wavelength conversion layer The layer can have green phosphor. The blue light-emitting element 63 may be a blue light-emitting diode chip. In addition, the control unit 7 may be a drive control chip, but is not limited thereto. It should be noted that the number, color, arrangement, etc. of the light-emitting elements can be adjusted and designed according to actual needs, and the present invention is not limited to the above examples. In some embodiments, the light emitting unit 6 may adopt an RGBW configuration. In some embodiments, the light emitting unit 6 may be a single light emitting diode chip.

In actual application, as shown in Figures 7, 8, 11, and 13, the light-emitting unit 6 may have four pins L1, L2, L3, and L4, and the conductive pad group 31 may include four conductive pads 31a, 31b, 31c, 31d, and the four pins L1, L2, L3, and L4 can be connected to the four conductive pads 31a, 31b, 31c, and 31d through conductive bumps B (bumpers) respectively. Furthermore, the pin L1 is a common pin of the red light-emitting element 61, the green light-emitting element 62 and the blue light-emitting element 63. The corresponding conductive pad 31a is connected to one of the adjacent grid structures M1. A reference signal (such as a reference voltage) is provided to the red light-emitting element 61 , the green light-emitting element 62 and the blue light-emitting element 63 . The pins L2, L3, and L4 are respectively the lead-out pins of the red light-emitting element 61, the green light-emitting element 62, and the blue light-emitting element 63. The corresponding conductive pads 31b, 31c, and 31d are respectively connected to the three second signal lines 32. , used to provide control electrical signals (such as control voltage) to the red light-emitting element 61 , the green light-emitting element 62 and the blue light-emitting element 63 . It should be noted that the number of pins L1, L2, L3, and L4 of the light-emitting unit 6 and the number of the conductive pads 31a, 31b, 31c, and 31d can be adjusted and designed according to actual needs. The present invention does not use the above-mentioned methods. Examples are limited.

[Third Embodiment]

Referring to FIGS. 15 and 16 , and as shown in FIGS. 17 to 19 , a third embodiment of the present invention provides a flexible circuit board Z, which mainly includes a flexible transparent substrate 1 and a first circuit layer 2 . The flexible transparent substrate 1 has an opposite first surface 101 and a second surface 102. The first surface 101 is, for example, an upper surface, and the second surface 102 is, for example, a lower surface. The first circuit layer 2 is formed on the first surface 101 of the flexible transparent substrate 1, and the current allowed by the first circuit layer 2 is at least greater than 1 × 10 ^-3 mA; the first circuit layer 2 includes a plurality of first signal lines 21 , which can be used as a power connection line to transmit electrical signals (current signals or voltage signals). It is worth mentioning that there is a predetermined distance D1 between two adjacent first signal lines 21, and the ratio of the wire diameter of each first signal line 21 to the predetermined distance D1 is 1:5 to 1:30. The difference between this embodiment and the previous embodiment is that the connection interface of the electronic component (such as a light-emitting element/component) is arranged on the first surface 101 of the flexible transparent substrate 1 and avoids the first circuit layer 2 position; that is to say, the flexible circuit board Z may further include a second circuit layer 3. The second circuit layer 3 is formed on the first surface 101 of the flexible transparent substrate 1 and does not overlap with the first circuit layer 2.

In this embodiment, the flexible transparent substrate 1 can be a plastic substrate with high transmittance to visible light (greater than 80%), and its material can include but is not limited to polyester (such as polyethylene terephthalate, Polyethylene terephthalate). ), polyimide, polycarbonate and cyclic olefin copolymer. The coverage rate of the first circuit layer 2 on the first surface 101 of the flexible transparent substrate 1 is in the range of 65% to 90%, and the wire diameter W of each first signal line 21 is in the range of 0.005 mm to 0.2 mm. within. In addition, several first signal lines 21 extend along the first direction X, and several first signal lines 21 extend along the second direction Y, and several first signal lines 21 extend along the first direction X. The lines 21 intersect with several first signal lines 21 extending along the second direction Y to form a plurality of grid structures M1 (upper grid structures); the first direction X and the second direction Y can be horizontal and vertical directions respectively. , as shown in Figure 15, or the first direction X and the second direction Y can be two different tilt directions, as shown in Figure 19. There are multiple specific areas A between multiple grid structures M1, that is, each specific area A is located in the space vacated between two adjacent grid structures M1; the flexible circuit board Z used as a transparent display screen , the specific area A may be a light-emitting pixel area, but the present invention is not limited thereto.

The second circuit layer 3 is coplanar with the first circuit layer 2, and defines a conductive pad group 31 and at least one second signal line 32 connected to the conductive pad group 31 in each specific area A; the second signal line The wire diameter 32 is the same as or different from the wire diameter W of the first signal wire 21 . In each specific area A, the conductive pad group 31 includes a plurality of conductive pads 31a, 31b, 31c, 31d, which can be used as a signal transmission interface and/or a connection interface for electronic components (such as light-emitting components/components). Secondly, The signal line 32 can be used as a signal connection line for transmitting control signals. During use, two of the conductive pads 31a and 31b are respectively connected to two adjacent grid structures M1, and the remaining conductive pads 31c and 31d are connected to at least one second signal line 32.

In this embodiment, in order to provide more power connection lines, the flexible circuit board Z may further include a fourth circuit layer 5. The fourth circuit layer 5 is formed on the second surface 102 of the flexible transparent substrate 1. The layer 5 can be electrically connected to the first circuit layer 2 through one or more via holes (not shown in the figure), but is not limited thereto. Furthermore, the coverage rate of the fourth circuit layer 5 on the second surface 102 of the flexible transparent substrate 1 is also in the range of 65% to 90%. The fourth circuit layer 5 includes a plurality of fourth signal lines 51, among which There is another predetermined distance D1 between two adjacent fourth signal lines 51; the wire diameter W of each fourth signal line 51 is in the range of 0.005 mm to 0.2 mm, and the wire diameter W of each fourth signal line 51 is The ratio of the diameter to this predetermined distance D1 is 1:5 to 1:30. Furthermore, several fourth signal lines 51 extend along the first direction X, and several fourth signal lines 51 extend along the second direction Y, and several fourth signal lines 51 extend along the first direction X. The lines 51 intersect with several fourth signal lines 51 extending along the second direction Y to form a plurality of grid structures M2 (underlying grid structures); the first direction X and the second direction Y can be horizontal and vertical directions respectively. , as shown in Figure 15, or the first direction X and the second direction Y can be two different tilt directions (not shown in the figure). Similarly, through the design of the fourth circuit layer 5, the visibility of the circuits in the display screen can be significantly reduced, the transparency of the display screen can be increased, and the display effect can be greatly improved.

In actual application, the plurality of mesh structures M2 (lower-layer mesh structures) based on the fourth signal line 51 and the plurality of mesh structures M1 (upper-layer mesh structure) based on the first signal line 21 are configured to correspond up and down, that is, The orthographic projection of the plurality of grid structures M2 on the flexible transparent substrate 1 overlaps the orthographic projection of the plurality of grid structures M1 on the flexible transparent substrate 1. In this way, the visibility of the fourth signal line 51 in the display screen can be reduced. , even when the circuit complexity increases, the overall transparency will not be affected.

As for the method of forming the first circuit layer 2, the second circuit layer 3 and the third circuit layer 4, reference can be made to the description in the first embodiment, so no further description will be given here.

Referring again to Figure 15 and Figures 17 to 19, and as shown in Figures 20 to 21, a third embodiment of the present invention also provides a flexible transparent display D, which mainly includes the above-mentioned flexible transparent substrate 1 and a plurality of light-emitting units. 6. A plurality of light-emitting units 6 are respectively disposed in a plurality of specific areas A of the flexible transparent substrate 1, and each light-emitting unit 6 is electrically connected and fixed to the conductive pad group 31 in the specific area A. In this embodiment, the plurality of light-emitting units 6 are evenly distributed on the first surface 101 of the flexible transparent substrate 1 in an array. The minimum separation distance (horizontal distance) between the plurality of light-emitting units 6 is preferably is in the range of 2 mm to 3 mm.

As shown in Figure 20, the light-emitting unit 6 can be a light-emitting diode package structure with a built-in control unit 7, which also includes a red light-emitting element 61, a green light-emitting element 62 and a blue light-emitting element 63 (using RGB configuration). The red light-emitting element 61 may be a red light-emitting diode chip, or the red light-emitting element 61 may include a blue light-emitting diode chip and a wavelength conversion layer formed on the blue light-emitting diode chip, wherein the wavelength conversion layer The layer can have red phosphor. The green light-emitting element 62 may be a green light-emitting diode chip, or the green light-emitting element 62 may include a blue light-emitting diode chip and a wavelength conversion layer formed on the blue light-emitting diode chip, wherein the wavelength conversion layer The layer can have green phosphor. The blue light-emitting element 63 may be a blue light-emitting diode chip. In addition, the control unit 7 may be a drive control chip, but is not limited thereto. It should be noted that the number, color, arrangement, etc. of the light-emitting elements can be adjusted and designed according to actual needs, and the present invention is not limited to the above examples. In some embodiments, the light emitting unit 6 may adopt an RGBW configuration. In some embodiments, the light emitting unit 6 may be a single light emitting diode chip.

In actual application, as shown in Figures 18, 20 and 21, the light-emitting unit 6 may have four pins L1, L2, L3, L4, and the conductive pad group 31 may include four conductive pads 31a, 31b, 31c, 31d. , and the four pins L1, L2, L3, and L4 can be connected to the four conductive pads 31a, 31b, 31c, and 31d through conductive bumps B (bumpers) respectively. Furthermore, the four pins L1, L2, L3, and L4 are respectively the power supply terminal (VDD), ground terminal (GND), signal input terminal (DIN), and signal output terminal (OUT) of the control unit 7. When in use, the control unit 7 can drive the red light-emitting element 61 , the green light-emitting element 62 and the blue light-emitting element 63 respectively according to the received signal, so that the red light-emitting element 61 , the green light-emitting element 62 and the blue light-emitting element 63 respectively Produce a target glow effect. It should be noted that the number of pins L1, L2, L3, and L4 of the light-emitting unit 6 and the number of the conductive pads 31a, 31b, 31c, and 31d can be adjusted and designed according to actual needs. The present invention does not use the above-mentioned methods. Examples are limited.

[Beneficial effects of the embodiment]

One of the beneficial effects of the present invention is that the flexible transparent display screen and its flexible circuit board of the present invention adopt "the first circuit layer is formed on the flexible transparent substrate and allows a current of at least greater than 1 × 10 ^-3 mA to pass through" and "The first circuit layer includes a plurality of first signal lines. There is a predetermined spacing between two adjacent first signal lines, and the ratio of the wire diameter of each first signal line to the predetermined spacing is 1:5 to 1 :30” technical features can significantly reduce the visibility of the lines in the display screen, increase the transparency of the display screen, and greatly improve the display effect.

In addition, the flexible circuit board of the present invention can configure other signal connection lines to correspond to the upper and lower parts of the first signal line to reduce the visibility of other signal lines in the display screen. In this way, even when the circuit complexity increases, It will not affect the overall transparency.

In addition, the flexible transparent display screen of the present invention can adapt to different three-dimensional shapes and has a wider range of applications, such as but not limited to shop windows, building exterior walls, automobiles, public transportation, etc.

The contents disclosed above are only preferred and feasible embodiments of the present invention, and do not limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made by using the description and drawings of the present invention are included in the application of the present invention. within the scope of the patent.

D: Flexible transparent display Z: Flexible circuit board 1: Flexible transparent substrate 101: First surface 102: Second surface A:Specific area 2: First line layer 21: First signal line M1: Grid structure 3: Second line layer 31:Conductive pad set 31a, 31b, 31c, 31d: conductive pad 32: Second signal line 4: The third line layer 41:Third signal line 5: The fourth line layer 51:Fourth signal line M2: Grid structure 6:Light-emitting unit 61:Red light-emitting component 62: Green light-emitting component 63:Blue light emitting element 7:Control unit 9a, 9b: Insulating layer B: Conductive bumps D1: Predetermined spacing D2: Minimum distance L1, L2, L3, L4: pins W: Wire diameter

FIG. 1 is a schematic top view of a flexible transparent display screen according to the first embodiment of the present invention.

Figure 2 is a schematic bottom view of the flexible transparent display screen according to the first embodiment of the present invention.

Figure 3 is a partial enlarged view of part III in Figure 1.

FIG. 4 is a schematic cross-sectional view of the IV-IV section in FIG. 1 .

FIG. 5 is a schematic cross-sectional view of the V-V section in FIG. 1 .

FIG. 6 is another schematic top view of the flexible transparent display screen according to the first embodiment of the present invention.

FIG. 7 is a schematic three-dimensional view of the light-emitting unit of the flexible transparent display screen according to the first embodiment of the present invention.

FIG. 8 is another three-dimensional schematic view of the light-emitting unit of the flexible transparent display screen according to the first embodiment of the present invention.

FIG. 9 is a schematic top view of the flexible transparent display screen according to the second embodiment of the present invention.

Figure 10 is a schematic bottom view of a flexible transparent display screen according to the second embodiment of the present invention.

FIG. 11 is a schematic cross-sectional view of the XI-XI section in FIG. 9 .

FIG. 12 is a schematic cross-sectional view of the XII-XII section in FIG. 9 .

Figure 13 is a partial enlarged view of part XIII in Figure 9.

Figure 14 is another schematic top view of the flexible transparent display screen according to the second embodiment of the present invention.

FIG. 15 is a schematic top view of a flexible transparent display screen according to the third embodiment of the present invention.

Figure 16 is a schematic bottom view of a flexible transparent display screen according to the third embodiment of the present invention.

FIG. 17 is a schematic cross-sectional view of the XVII-XVII section in FIG. 15 .

FIG. 18 is a partial enlarged view of part XVIII of FIG. 15 .

Figure 19 is another schematic top view of the flexible transparent display screen according to the third embodiment of the present invention.

FIG. 20 is a schematic three-dimensional view of the light-emitting unit of the flexible transparent display screen according to the third embodiment of the present invention.

FIG. 21 is another three-dimensional schematic view of the light-emitting unit of the flexible transparent display screen according to the third embodiment of the present invention.

D: Flexible transparent display

Z: Flexible circuit board

1: Flexible transparent substrate

101: First surface

A:Specific area

2: First line layer

21: First signal line

M1: Grid structure

3: Second line layer

31:Conductive pad set

32: Second signal line

6:Light-emitting unit

7:Control unit

D2: Minimum distance

Claims (10)

A flexible circuit board, including: a flexible transparent substrate, the flexible transparent substrate has a first surface and a second surface opposite; and a first circuit layer, the first circuit layer is formed on the first surface above, wherein the first circuit layer includes a plurality of first signal lines, there is a predetermined spacing between two adjacent first signal lines, and the wire diameter of each first signal line is consistent with the diameter of the first signal line. The ratio of the predetermined spacing is 1:5 to 1:30; furthermore, several of the first signal lines intersect with other several of the first signal lines to form a plurality of upper layer grid structures, and a plurality of the upper layer A plurality of specific areas are left between the grid structures; a second circuit layer is formed on the third part of the flexible transparent substrate in a manner to avoid the locations of multiple upper grid structures. On a surface, the second circuit layer defines a conductive pad group and at least one second signal line connected to the conductive pad group in each of the specific areas; a fourth circuit layer, the A fourth circuit layer is formed on the second surface of the flexible transparent substrate and is electrically connected to the first circuit layer, wherein the fourth circuit layer includes a plurality of fourth signal lines arranged at intervals. There is another predetermined spacing between two adjacent fourth signal lines, and the ratio of the diameter of each fourth signal line to the other predetermined spacing is 1:5 to 1:30; and, Several of the fourth signal lines intersect with several other fourth signal lines to form a plurality of lower grid structures, and the plurality of lower grid structures correspond vertically to the plurality of upper grid structures. . The flexible circuit board according to claim 1, wherein the wire diameter of each of the first signal lines is 0.005 mm to 0.2 mm. The flexible circuit board according to claim 1, wherein the first circuit layer is The coverage of the first surface is 65% to 90%. The flexible circuit board according to claim 1, wherein in each of the specific areas, the conductive pad group includes a plurality of conductive pads, wherein two of the conductive pads are respectively connected to two adjacent meshes. The grid structures are connected, and the remaining conductive pads are connected to at least one of the second signal lines. The flexible circuit board according to claim 1, wherein the wire diameter of each of the fourth signal lines is 0.005 mm to 0.2 mm. The flexible circuit board according to claim 1, wherein the coverage rate of the fourth circuit layer on the second surface is 65% to 90%. The flexible circuit board according to claim 1, wherein the first circuit layer allows a current of at least greater than 1×10 ^-3 mA to pass through. A flexible transparent display screen, which includes the flexible circuit board as described in any one of claims 1 to 7 and a plurality of light-emitting units, and the plurality of said light-emitting units are arranged on the flexible circuit board. The flexible transparent display screen according to claim 8, wherein the flexible transparent display screen further includes one or more control units, and the control units are electrically connected to the flexible circuit board. The flexible transparent display screen according to claim 8, wherein each of the light-emitting units has a built-in control unit.

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