Backlight circuit board, backlight key and keyboard

Abstract

The utility model discloses a backlight circuit board, a backlight key and a keyboard. The backlight circuit board is used for bearing key caps. The backlight circuit board comprises a substrate, a light-emitting circuit and a light source, the substrate is provided with a plurality of ribs and a plurality of connecting pieces, the ribs define a plurality of broken holes, the broken holes penetrate through the substrate, and the connecting pieces are arranged on the substrate and used for being directly or indirectly connected with the key caps. The light-emitting circuit is arranged on the substrate and is positioned on the same side of the plurality of connecting pieces, and the light-emitting circuit extends along the upper parts of the plurality of rib parts of the substrate; the light source is electrically connected with the light-emitting circuit, the light source is arranged above one of the plurality of rib parts of the substrate, the light source vertically corresponds to the non-light-emitting area of the keycap, and the vertical projection of the non-light-emitting area is at least partially overlapped with the plurality of rib parts of the substrate. According to the utility model, the overall key thickness can be effectively reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to a backlight circuit board, specifically, the utility model relates to a backlight circuit board with a key connecting piece and a backlight key and keyboard comprising the backlight circuit board. BACKGROUND

[0002] In the prior art, the backlight key and the keyboard are usually manufactured separately from the key structure generating a trigger signal and the backlight module providing backlight, and then the key structure and the backlight module are bonded together. However, the key structure and the backlight module in the prior art are both multi-layer stacked structures, so that the overall thickness of the backlight key (or keyboard) cannot be successfully reduced, which is not conducive to the thinness of the device. SUMMARY

[0003] One object of the utility model is to provide a backlight circuit board which can not only serve as a bottom plate of a key structure, but also has a light-emitting circuit and can simultaneously serve as a light source circuit board.

[0004] Another object of the utility model is to provide a backlight circuit board which integrates a light-emitting circuit in a bottom plate of a key structure, effectively reducing the overall key thickness.

[0005] In one embodiment, the backlight circuit board of the utility model is used to carry a keycap, and the backlight circuit board comprises a substrate, a light-emitting circuit, and a light source. The substrate has a plurality of ribs and a plurality of connecting pieces, the plurality of ribs define a plurality of broken holes, the plurality of broken holes penetrate the substrate, and the plurality of connecting pieces are arranged on the substrate and are used to directly or indirectly connect the keycap. The light-emitting circuit is arranged on the substrate and is located on the same side of the plurality of connecting pieces, and the light-emitting circuit extends above the plurality of ribs of the substrate. The light source is electrically connected to the light-emitting circuit, and the light source is arranged above at least one of the plurality of ribs of the substrate. The light source at least partially corresponds to a non-light-emitting area of the keycap in a vertical direction, and the vertical projection of the non-light-emitting area at least partially overlaps the plurality of ribs of the substrate.

[0006] In one embodiment, the substrate is a non-metal plate, so that the upper surface of the substrate is an insulating surface.

[0007] In one embodiment, the substrate comprises a metal plate and an insulating layer, and the insulating layer at least partially covers the upper surface of the metal plate.

[0008] In one embodiment, the backlight circuit board of the utility model further comprises a switch circuit layer, wherein the switch circuit layer and the light-emitting circuit are arranged on the same side of the substrate, the switch circuit layer has a switch unit, and the vertical projection of the switch unit does not overlap the light source.

[0009] In one embodiment, the switch circuit layer has a first hole, and the first hole corresponds to the light source.

[0010] In one embodiment, the switch circuit layer has a second hole, and the second hole corresponds to at least one of the plurality of connecting members.

[0011] In one embodiment, the switch circuit layer has a switch circuit, the switch circuit is electrically connected to the switch unit, and a vertical projection of the switch circuit and the light-emitting circuit at least partially overlaps one of the plurality of ribs.

[0012] In one embodiment, the vertical projections of the switch unit and the light source are both located within a range commonly surrounded by the plurality of connecting members.

[0013] In one embodiment, the backlight circuit board of the utility model further comprises a light-absorbing layer, wherein the light-absorbing layer is arranged on the switch circuit layer to define at least one light-transmitting window corresponding to the keycap.

[0014] In one embodiment, the backlight circuit board of the utility model further comprises a protective layer, wherein the protective layer is arranged on the substrate to cover the light-emitting circuit, and the protective layer has a reflective surface and / or microstructure located within a vertical projection range of at least one light-transmitting window.

[0015] In one embodiment, the protective layer has a reflective surface and / or microstructure, and the microstructure overlaps at least one of the plurality of ribs of the substrate.

[0016] In one embodiment, the plurality of connecting members extend from the substrate to above the light-emitting circuit.

[0017] In another embodiment, the utility model provides a backlight key, which comprises the backlight circuit board and the keycap.

[0018] In yet another embodiment, the utility model provides a backlight keyboard, which comprises the backlight circuit board and the keycap.

[0019] In still another embodiment, the utility model provides a backlight key, which comprises a keycap, a circuit board, a circuit film, and an adhesive layer, wherein the circuit board has a light-emitting circuit, a light source, and a plurality of connecting members, the plurality of connecting members are used to directly or indirectly connect the keycap, the light-emitting circuit is arranged on an upper surface of the circuit board and is electrically connected to the light source; the circuit film is arranged between the keycap and the circuit board, and has a film hole for accommodating the light source; the adhesive layer is arranged around the film hole and bonds the circuit board and the circuit film, and has a glue-free area between the adhesive layer and the film hole.

[0020] In one embodiment, the keycap has a light-emitting area and a non-light-emitting area, and the light source is at least partially located outside a vertical projection range of the light-emitting area.

[0021] In one embodiment, the circuit film has a switch unit, and a vertical projection of the switch unit does not overlap the light source.

[0022] In one embodiment, the backlight key of the utility model further comprises a reflective layer, wherein the reflective layer at least partially covers the light source.

[0023] In one embodiment, the backlight module further comprises a light absorbing layer, wherein the light absorbing layer is disposed on the circuit film to define at least one light transmission window corresponding to the keycap.

[0024] In one embodiment, the backlight module further comprises a light absorbing layer, wherein the light absorbing layer is disposed on the circuit film to define at least one light transmission window corresponding to the keycap.

[0025] In one embodiment, the circuit film is a multi-layer structure, wherein the film hole is a through hole penetrating the multi-layer structure or a blind hole disposed on at least one layer of the multi-layer structure.

[0026] In one embodiment, the circuit film has a microstructure, and when the film hole is a blind hole disposed on at least one layer of the multi-layer structure, the microstructure is disposed on at least one layer of the multi-layer structure.

[0027] In one embodiment, the adhesive layer is an open ring-shaped adhesive layer with an adhesive layer gap.

[0028] Compared with the prior art, the backlight circuit board of the present application not only can be used as the bottom plate of the key structure, but also has a light emitting circuit and can be used as a light source circuit board. Furthermore, the backlight circuit board of the present application integrates the light emitting circuit in the bottom plate of the key structure, effectively reducing the overall key thickness and promoting thin design. The backlight key of the present application accommodates the light source in the film hole of the circuit film, which can eliminate the additional light guide plate by the light guide effect of the circuit film, further promoting thin design.

[0029] The present application will be described in detail below in conjunction with the drawings and specific embodiments, but not as a limitation on the present application. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is a schematic view of the backlight keyboard of one embodiment of the present application.

[0031] Figure 2 is a schematic view of the backlight key of one embodiment of the present application.

[0032] Figure 3 is a schematic view of the backlight key of one embodiment of the present application.

[0033] Figure 4 is a schematic view of the backlight circuit board of one embodiment of the present application.

[0034] Figure 5 is a schematic view of the backlight key of one embodiment of the present application.

[0035] Figure 6The top view schematic diagram of the arrangement of the upper surface of the backlight circuit board and the light source in another embodiment of the present application is shown in FIG. 1B. DETAILED DESCRIPTION

[0036] To further understand the purpose, structure, features and functions of the present application, the following embodiments are described in detail.

[0037] The following embodiments are described with reference to the accompanying drawings, which are used to illustrate specific embodiments of the present application that can be implemented. The directions mentioned in the present application, such as "up", "down", "front", "back", "left", "right", "side", etc. are only the directions of the accompanying drawings. Therefore, the directions used are used to explain and understand the present application, not to limit the present application.

[0038] The present application mainly relates to the integration of the bottom plate of the key structure and the light-emitting circuit, which can reduce the overall thickness of the key and improve the light-emitting efficiency and uniformity of the single key and even the whole key panel. Please refer to Figure 1 and Figure 2 , Figure 1 The stacking schematic diagram of the backlight keyboard KB of an embodiment of the present application is shown in FIG. 1A, and Figure 2 The cross-sectional schematic diagram of the backlight key 1 of an embodiment of the present application is shown in FIG. 1C. In an embodiment, the backlight keyboard KB of the present application includes a plurality of keys KS (such as square keys SK or multiple keys MK), wherein each key KS (such as the backlight key 1 of Figure 2 The backlight key 1 includes a key cap 12, a lifting mechanism 14, a switch circuit layer 16, a reset member 18 and a backlight circuit board 10. For the backlight keyboard KB, the backlight circuit board 10 has a light-emitting circuit 120 and a light source 130, so that the backlight circuit board 10 can simultaneously serve as the bottom plate of the key KS and the light source circuit board.

[0039] As Figure 2As shown, the keycap 12 is disposed above the backlight circuit board 10 and has a light emitting area 122 (e.g. one or more light transmissive characters) and a non-light emitting area 124. The lifting mechanism 14 is connected between the backlight circuit board 10 and the keycap 12 to support the keycap 12 to move up / down relative to the backlight circuit board 10. The switch circuit layer 16 is disposed below the keycap 12 and preferably on the backlight circuit board 10. The switch circuit layer 16 has a switch unit 162 and a switch circuit 164 electrically connected to the switch unit 162. When the keycap 12 is pressed, the switch unit 162 of the switch circuit layer 16 is turned on to generate a trigger signal. The restoring member 18 is disposed between the keycap 12 and the backlight circuit board 10 to provide a restoring force to allow the keycap 12 to move up relative to the backlight circuit board 10 to return to the position before being pressed after being pressed. In this embodiment, the restoring member 18 can be implemented as a rubber dome and is disposed corresponding to the switch unit 162. When the keycap 12 is pressed to move downward to press the restoring member 18, a trigger portion 182 of the restoring member 18 can trigger the switch unit 162, but not limited thereto. The switch unit 162 can be triggered by the trigger portion, and the trigger portion can be disposed on the restoring member 18, the lifting mechanism 14 or the keycap 12, etc. According to actual application, the restoring member 18 can be implemented as any element capable of providing a restoring force to drive the keycap 12 to return after being pressed, such as a spring, a magnetic member, etc., and the switch of the backlight key 1 is not limited to the switch unit 162 in the form of the switch circuit layer 16, but any suitable switch that can be triggered according to the pressing of the keycap 12 is suitable for the present application, such as a mechanical switch, a magnetic switch, an optical switch, etc. In this embodiment, the lifting mechanism 14 is implemented as a scissor lifting mechanism having two brackets pivotally connected to each other and having two ends of each bracket movably connected to the backlight circuit board 10 and the keycap 12, but not limited thereto. According to actual application, the lifting mechanism 14 can be implemented as a butterfly lifting mechanism, a cantilever lifting mechanism, etc. The above backlight circuit board 10, keycap 12, lifting mechanism 14, switch circuit layer 16 and restoring member 18 can constitute the backlight key 1. The backlight circuit board 10 of the present application will be described in detail later.

[0040] Please refer to Figure 2 and Figure 3 , Figure 3The backlight circuit board 10 is used to carry at least one keycap (for example, the keycap 12), and the backlight circuit board 10 can include a substrate 110, a light-emitting circuit 120, and a light source 130. The substrate 110 has a plurality of ribs (for example, 117a, 117b1, 117b2, and 117c) and a plurality of connecting members 115. The plurality of ribs define a plurality of broken holes (for example, 113c and 113p), and the plurality of broken holes penetrate the substrate 110. Specifically, the substrate 110 has a plurality of ribs, such as the frame rib 117a, the first bridge rib 117b1, the second bridge rib 117b2, and the middle island rib 117c, to define, for example, one central broken hole 113c and a plurality (for example, four) of peripheral broken holes 113p. For example, the frame rib 117a is arranged in a frame shape corresponding to the periphery of the keycap 12 and serves as a component for connecting with other adjacent keys. The middle island rib 117c is arranged at or near the center of the keycap 12 and is surrounded by the frame rib 117a. The first bridge rib 117b1 and the second bridge rib 117b2 respectively connect the frame rib 117a and the middle island rib 117c in different directions (for example, vertical and horizontal directions) to define, for example, four peripheral broken holes 113p between the frame rib 117a and the plurality of bridge ribs (for example, the first bridge rib 117b1 and the second bridge rib 117b2). From another point of view, the first bridge rib 117b1 and the second bridge rib 117b2 are connecting ribs that extend radially from the middle island rib 117c to the frame rib 117a and are used to connect the middle island rib 117c and the frame rib 117a. In this embodiment, the middle island rib 117c can be configured in a ring shape, so that the middle island rib 117c defines the central broken hole 113c located in the center of the ring, but this is not limited. According to actual application, the middle island rib 117c can be a solid middle island, so that the substrate 110 can not have the central broken hole 113c. It should be noted that the shape, number, position, etc. of the ribs and broken holes can be determined according to factors such as the structural strength of the backlight key 1, the position of the light-emitting area 122 of the keycap 12, the power of the light source 130, etc. The plurality of connecting members 115 are arranged on the substrate 110 and are used to directly or indirectly connect the keycap 12. In this embodiment, the connecting member 115 can be a hook-shaped connecting member, and the keycap 12 and the backlight circuit board 10 are connected by coupling the connecting member 115 with the lifting mechanism 14, but this is not limited. According to actual application, the connecting member 115 can be in the form of a clamping groove, a clamping column, etc. In one embodiment, the keycap 12 has a hook, which is directly connected with the connecting member 115 having a guide-type clamping groove structure, and at this time, the lifting mechanism 14 can not be arranged.

[0041] In one embodiment, the substrate 110 can include a metal plate 112 and an insulating layer 114, wherein the insulating layer 114 at least partially covers the upper surface of the metal plate 112, such that the upper surface of the substrate 110 (e.g., the upper surface of the insulating layer 114) is an insulating surface. The metal plate 112 can be a conductive substrate such as an aluminum alloy or a steel plate, such that the metal plate 112 itself can shield radio waves and serve as a grounding component to reduce electrostatic discharge (ESD) problems. The insulating layer 114 can be formed on at least the upper surface of the metal plate 112 by any suitable means such as bonding, printing, coating, deposition, molding, etc., to form an insulating surface on the upper surface of the substrate 110. For example, the insulating layer 114 can be disposed on the entire upper surface of the metal plate 112 or only on the partial upper surface of the metal plate 112 where the light-emitting circuit 120 is to be disposed. In one embodiment (not shown), the insulating layer 114 can further cover the walls of the through-holes (113c, 113p) or other through-holes, the edge side walls of the metal plate 112, the surfaces of the connectors 115, and / or the lower surface of the metal plate 112 to avoid exposing the metal plate 112 to cause electrostatic discharge (ESD) problems. Furthermore, the insulating layer 114 can include any insulating material that can electrically isolate the metal plate 112 and the conductive circuit (e.g., the light-emitting circuit 120), such as a polymer material, a dielectric material, etc. When the substrate 110 employs the metal plate 112, the connectors 115 can be formed by, for example, (1) stamping the metal plate into a flat shape and then bending the connectors to stand on the surface of the metal plate, (2) using insert-molding to form plastic connectors on the metal plate, or (3) using hot melting to fix pre-formed plastic connectors on the metal plate, but are not limited thereto. In another embodiment, the substrate 110 can be a non-metallic plate such as a glass fiber, a carbon fiber, a man-made resin, a polymer material, etc., such that the upper surface of the substrate 110 (e.g., the upper surface of the non-metallic plate) is an insulating surface. When the substrate 110 employs the non-metallic plate, the connectors 115 can be fixed on the substrate 110 by, for example, (1) using a mold to form the substrate 110 with the connectors 115 in one shot, (2) using insert-molding to form plastic connectors on the non-metallic plate, (3) using hot melting to fix pre-formed plastic connectors on the non-metallic plate, (4) fixing a metal frame with the connectors 115 on the non-metallic plate, or (5) fixing a metal frame on the non-metallic plate and then using hot melting to fix pre-formed plastic connectors on the metal frame, but are not limited thereto.

[0042] Please also refer to Figure 2 , Figure 3 and Figure 4 wherein Figure 4As shown in the figure, the light-emitting circuit 120 is disposed on the substrate 110 and located on the same side of the plurality of connecting members 115, and the light-emitting circuit 120 preferably extends above the plurality of rib portions (for example, 117a, 117b1, 117b2, 117c) of the substrate 110. Specifically, the connecting members 115 and the light-emitting circuit 120 are both located on the upper surface of the substrate 110, and the plurality of connecting members 115 preferably extend from the substrate 110 to above the light-emitting circuit 120. The light-emitting circuit 120 can be formed on the upper surface of the substrate 110 by printing metal paste (for example, silver paste) or by etching a metal foil circuit from a whole metal foil (for example, a copper foil). The light-emitting circuit 120 can include a main circuit 121 and a sub-circuit 123 for electrically connecting the light source 130 and a driving element (not shown) so that the light source 130 can be driven to emit light. From another point of view, the light-emitting circuit 120 is preferably formed on at least one of the plurality of rib portions of the substrate 110 and does not shield the broken holes (for example, 113c, 113p) of the substrate 110, so that the light-emitting circuit 120 can be considered as a circuit layer having openings corresponding to the broken holes (for example, 113p). The plurality of connecting members 115 are arranged in pairs corresponding to the plurality of peripheral broken holes 113p, and can protrude above the light-emitting circuit 120 through the openings of the light-emitting circuit 120 corresponding to the peripheral broken holes 113p to the upper surface of the substrate 110.

[0043] The light source 130 is electrically connected to the light-emitting circuit 120 to receive power for driving the light source 130 to emit light through the light-emitting circuit 120. For example, the light source 130 can be fixed to the light-emitting circuit 120 by a conductive adhesive layer to electrically connect the light-emitting circuit 120, but is not limited thereto. In another embodiment, the light source 130 can be fixed to the upper surface of the substrate 110 by a non-conductive adhesive layer, and then electrically connected to the light-emitting circuit 120 by other conductive circuits. The light source 130 can be implemented as a single-chip or multi-chip light-emitting diode. In an embodiment, the light source 130 can be a low-brightness, low-power mini light-emitting diode (mini LED) or micro light-emitting diode (micro LED) mainly emitting light from the top surface. The backlight key 1 can have one or more light sources 130, and the light source 130 is preferably disposed above one of the plurality of rib portions of the substrate 110. For example, in this embodiment, two light sources 130 are disposed on the first bridge rib 117b1 and are located on opposite sides of the middle island rib 117c. Furthermore, to avoid excessive brightness directly above the light source 130, the light source 130 preferably does not overlap the vertical projection of the light-emitting area 122 of the keycap 12, so that the light source 130 is at least partially outside the vertical projection range of the light-emitting area 122. In other words, the light source 130 preferably vertically corresponds to the non-light-emitting area 124 of the keycap 12, and the vertical projection of the non-light-emitting area 124 at least partially overlaps the plurality of rib portions (for example, 117a, 117b1, 117b2, 117c) of the substrate 110. In this embodiment, asFigure 3 As shown, since the plurality of light sources 130 (e.g., two light sources) are respectively disposed on the first bridge ribs 117b1 on both sides of the middle island rib 117c, the width of the first bridge ribs 117b1 is preferably relatively greater than the width of the second bridge ribs 117b2. The "width" described herein refers to the distance between two peripheral break holes 113p disposed on both sides of the bridge rib along the extension direction of the bridge rib toward the frame rib. For example, the width of the first bridge ribs 117b1 can be the distance between the left and right adjacent peripheral break holes 113p on the upper side (or lower side) of the first bridge ribs 117b1, and the width of the second bridge ribs 117b2 can be the distance between the upper and lower adjacent peripheral break holes 113p on the left side (or right side) of the second bridge ribs 117b2. Figure 3 The width of the first bridge ribs 117b1 can be the distance between the left and right adjacent peripheral break holes 113p on the upper side (or lower side) of the first bridge ribs 117b1, and the width of the second bridge ribs 117b2 can be the distance between the upper and lower adjacent peripheral break holes 113p on the left side (or right side) of the second bridge ribs 117b2. Figure 3 The width of the first bridge ribs 117b1 can be the distance between the left and right adjacent peripheral break holes 113p on the upper side (or lower side) of the first bridge ribs 117b1, and the width of the second bridge ribs 117b2 can be the distance between the upper and lower adjacent peripheral break holes 113p on the left side (or right side) of the second bridge ribs 117b2.

[0044] Furthermore, the backlight circuit board 10 can further selectively include a protective layer 140 disposed on the substrate 110 and covering the light-emitting lines 120, thereby providing waterproof and insulating effects for the light-emitting lines 120. In an embodiment, the protective layer 140 preferably has a reflective surface 146 and / or a microstructure 144, which can diffuse light to make the characters on the keycaps of each key emit light uniformly and make the brightness of the halo of each key consistent. In an embodiment, the microstructure 144 overlaps at least one of the plurality of ribs (e.g., 117a, 117b1, 117b2, 117c) of the substrate 110. The protective layer 140 is preferably formed of an insulating material having reflectivity, so that the upper surface (i.e., the surface away from the substrate 110) of the protective layer 140 can serve as the reflective surface 146. In an embodiment, the protective layer 140 can be formed on the upper surface of the substrate 110 by, for example, printing, by white paint or white ink. The protective layer 140 preferably covers the upper surface of the substrate 110 except for the position of the light source 130 and the light-emitting lines 120, and has a larger reflective surface 146. From another perspective, the protective layer 140 can be considered as an insulating reflective film having apertures 142, and the apertures 142 correspond to the positions of the light sources 130, so that the light sources 130 can protrude from the apertures 142 of the protective layer 140 towards the keycaps 12. Furthermore, the protective layer 140 can have through-holes (e.g., 148p, 148c) at positions corresponding to the broken holes (e.g., 113p, 113c) of the substrate 110, to communicate with the broken holes of the substrate 110. For example, the protective layer 140 can have a peripheral through-hole 148p corresponding to (or communicating with) the peripheral broken hole 113c and a central through-hole 148c corresponding to (or communicating with) the central broken hole 113c, but the disclosure is not limited thereto. Depending on the actual application, when the protective layer 140 is formed of a light-transmitting film, the protective layer 140 can not be provided with through-holes, and the reflective surface 146 of the protective layer 140 can be formed on the upper surface of the protective layer 140 by a reflective material or coating. In an embodiment, the microstructure 144 of the protective layer 140 preferably corresponds to at least one of the plurality of ribs (e.g., 117a, 117b1, 117b2, 117c) of the substrate 110, so that the microstructure 144 and the at least one rib at least partially overlap in the stacking direction. On the other hand, the microstructure 144 of the protective layer 140 preferably corresponds to the non-light-emitting area 124 of the keycap 12, so that the microstructure 144 and the non-light-emitting area 124 of the keycap 12 at least partially overlap in the stacking direction.

[0045] In this embodiment, the switch circuit layer 16 and the light emitting circuit 120 are disposed on the same side (e.g., the upper side) of the substrate 110. The vertical projections of the switch units 162 of the switch circuit layer 16 and the light source 130 are both within the common range surrounded by the plurality of connecting members 115, and the vertical projection of the switch units 162 does not overlap the light source 130. The switch circuit layer 16 can have one or more layers of structure, and the switch circuit 164 is formed in one or more of the layers. In one embodiment, the switch circuit layer 16 can be implemented as a membrane switch having a multi-layer structure, in which the switch units 162 and the switch circuit 164 can be disposed on one or more of the layers of the membrane switch, and can be moved downward with the key cap 12 to trigger the switch units 162 by the trigger portions 182. When the switch circuit layer 16 is implemented in the form of a membrane switch, the trigger portions 182 can be non-conductive or conductive trigger portions. In another embodiment, the switch circuit layer 16 can be formed by printing or wire etching process to form the switch units 162 and the switch circuit 164 on the upper surface of the protective layer 140, so that the backlight circuit board 10 further integrates the switch circuit, while serving as the bottom plate of the key structure, the switch circuit board of the key structure, and the light source circuit board, and more effectively achieves the thinness of the key structure. It should be noted that when the switch circuit layer 16 is formed by printing or wire etching process to form the switch units 162 and the switch circuit 164 on the upper surface of the protective layer 140, the trigger portions 182 are preferably conductive trigger portions to make the switch units 162 in the form of switch pads conductive by the conductive trigger portions 182. The switch circuit 164 preferably extends above the plurality of ribs (e.g., 117a, 117b1, 117b2, 117c) of the substrate 110, so that the vertical projections of the switch circuit 164 of the switch circuit layer 16 and the light emitting circuit 120 at least partially overlap one of the plurality of ribs, such as the first bridge rib 117b1 as shown in Figure 3

[0046] As shown in Figure 2 , the switch circuit layer 16 preferably has a first hole 165, and the first hole 165 corresponds to the light source 130. For example, the first hole 165 can be a through hole penetrating the switch circuit layer 16, so that the light source 130 is accommodated in the first hole 165 or even protrudes from the first hole 165 to be exposed from the first hole 165. Figure 2 ​Although the light source 130 is shown to have a height exceeding the upper surface of the switch circuit layer 16, this is merely for the purpose of presenting the concept of the present embodiment (e.g. the switch circuit layer 16 is a single layer circuit structure). Depending on the actual application, the height of the light source 130 can be equal to or lower than the upper surface of the switch circuit layer 16. For example, when the switch circuit layer 16 is formed on the upper surface of the protective layer 140 by a printing or wire etching process, the first hole 165 can be a portion of the protective layer 140 around the light source 130 where no switch circuit 164 is formed, in which case the first hole 165 can be considered as a through hole penetrating the switch circuit layer 16, and the height of the light source 130 can exceed the upper surface of the switch circuit layer 16, but not limited thereto. When the switch circuit layer 16 is implemented as a circuit film having a multi-layer structure, the first hole 165 is a film hole formed in the circuit film, and this film hole can be a through hole penetrating the multi-layer structure (the height of the light source 130 can exceed or be equal to the upper surface of the switch circuit layer 16) or a blind hole provided in at least one layer (e.g. the upper layer) of the multi-layer structure (the height of the light source 130 is lower than the upper surface of the switch circuit layer 16).

[0047] In the present embodiment, the switch circuit layer 16 preferably further has a second hole 166, and the second hole 166 corresponds to at least one of the plurality of connecting members 115. For example, the second hole 166 can be a through hole penetrating the switch circuit layer 16, and the second hole 166 is in communication with the peripheral broken hole 113p where the connecting member 115 is located. The second hole 166 can accommodate the partial sinking of the bracket of the lifting mechanism 14, so as to reduce the thickness (or height) of the overall key. For example, when the switch circuit layer 16 is formed on the upper surface of the protective layer 140 by a printing or wire etching process, the second hole 166 can be a portion of the protective layer 140 around the peripheral broken hole 113p where no switch circuit 164 is formed, but not limited thereto. When the switch circuit layer 16 is implemented as a circuit film having a multi-layer structure, the second hole 166 is a film hole formed in the circuit film, and this film hole can be a through hole penetrating the multi-layer structure or a blind hole provided in at least one layer (e.g. the upper layer) of the multi-layer structure.

[0048] The backlight circuit board 10 can further include a light absorbing layer 150, and the light absorbing layer 150 is provided on the switch circuit layer 16 to define at least one light transmission window 152 corresponding to the keycap 12. The light absorbing layer 150 is preferably formed on the upper surface of the switch circuit layer 16 by any suitable means (e.g. printing) using a light absorbing material (e.g. black paint or black ink) to define at least one light transmission window 152. As shown in FIG. 1, the light absorbing layer 150 is formed on the upper surface of the switch circuit layer 16 to define a plurality of light transmission windows 152 corresponding to the plurality of keys 110, and the light absorbing layer 150 is not formed on the peripheral broken hole 113p where the connecting member 115 is located. Figure 3As shown, the light-absorbing layer 150 can be disposed along the frame ribs 117a to form frame-shaped light-transmitting windows 152, and the light-transmitting windows 152 are preferably recessed relative to the contour of the keycap 12 to improve the edge halo consistency of the keycap 12. However, this is not the case. In an embodiment, the reflective surface 146 and / or the microstructure 144 of the protective layer 140 are preferably located within the vertical projection range of at least one light-transmitting window 152. If there is a need for uniform brightness (such as the edge halo of the keycap 12 or the characters of the keycap 12) or multi-color light source light mixing, by disposing the reflective surface 146 and / or the microstructure 144 of the protective layer 140 on the bridge ribs (such as 117b1, 117b2) and the middle island rib 117c that are not covered by the light-absorbing layer 150, the light scattering and diffusion effect can be provided to achieve the secondary reflection and refraction of light between the keycap 12 and the backlight circuit board 10, thereby improving the light-emitting effect.

[0049] As shown, Figure 4 When the switch circuit layer 16 is implemented as a circuit film, the backlight circuit board 10 can further have a glue layer 170, wherein the glue layer 170 is disposed around the first hole 165 as a film hole and bonds the backlight circuit board 10 and the switch circuit layer 16 as a circuit film, and the glue layer 170 and the first hole 165 have a glue-free area 171. Specifically, the glue layer 170 is located around the first hole 165 corresponding to the light source 130, so that the switch circuit layer 16 and the light source 130 can be positioned by the glue layer 170, thereby improving the stability of light coupling. The glue layer 170 and the hole edge of the first hole 165 of the switch circuit layer 16 have a glue-free area 171, i.e., the area around the first hole 165 where the glue layer 170 is not disposed. Furthermore, the switch circuit layer 16 as a circuit film preferably has a microstructure 168, and the glue-free area 171 can be provided with the microstructure 168 of the switch circuit layer 16 and / or the microstructure 144 of the protective layer 140.

[0050] Please refer to Figure 5 , Figure 5 is a cross-sectional view of the backlight key of another embodiment of the utility model. As shown, Figure 5As shown, the backlight key 1 includes a keycap 12, a circuit board (e.g., backlight circuit board 10), a circuit film (e.g., switch circuit layer 16), and a glue layer 170. Similar to the above-mentioned embodiments, the circuit board has a light-emitting circuit 120, a light source 130, and a plurality of connectors 115. The plurality of connectors 115 are used to directly or indirectly connect the keycap 12. The light-emitting circuit 120 is disposed on the upper surface of the circuit board and is electrically connected to the light source 130. The circuit film is disposed between the keycap 12 and the circuit board. The circuit film has a film hole (e.g., first hole 165) for accommodating the light source 130. The glue layer 170 is disposed around the film hole and bonds the circuit board (e.g., 10) and the circuit film (e.g., 16). The glue layer 170 has a glue-free area 171 between the film hole. In this embodiment, the details of the keycap 12, the circuit board, the circuit film, and the glue layer can refer to the above-mentioned embodiments of the keycap 12, the backlight circuit board 10, the switch circuit layer 16, and the glue layer 170. The differences between the present embodiment and the above-mentioned embodiments will be described below.

[0051] In this embodiment, the circuit film can be a switch circuit layer 16 having a multi-layer structure. For example, the switch circuit layer 16 is a three-layer structure including a first layer 16a, a second layer 16b, and a spacing layer 16c disposed between the first layer 16a and the second layer 16b, but is not limited thereto. The switch circuit layer 16 can be a multi-layer structure including two or more layers, and each layer can include a light-transmitting film, such as a PET film. In this embodiment, the switch circuit 164 includes a first switch circuit 164a disposed in the first layer 16a and a second switch circuit 164b disposed in the second layer 16b. The switch unit 162 includes a first switch pad 162a disposed in the first layer 16a and a second switch pad 162b disposed in the second layer 16b. The first switch circuit 164a is electrically connected to the first switch pad 162a, and the second switch circuit 164b is electrically connected to the second switch pad 162b. The spacing layer 16c is used to separate the first switch circuit 164a and the first switch pad 162a disposed in the first layer 16a from the second switch circuit 164b and the second switch pad 162b disposed in the second layer 16b. The spacing layer 16 has a hole at a position corresponding to the first switch pad 162a and the second switch pad 162b, so that when the keycap 12 moves downward, the trigger portion (e.g., 182 of the above-mentioned embodiments) presses against the first switch pad 162a, causing the first switch pad 162a to contact the second switch pad 162b to conduct and generate a key signal.

[0052] Furthermore, in this embodiment, the first hole 165 in the switch circuit layer 16 as a film hole is a blind hole disposed in at least one layer of the multi-layer structure. For example, the first hole 165 can be a single-layer film hole formed in the second layer 16b, or a double-layer film hole formed in the second layer 16b and the spacer layer 16c. In this way, the light emitted by the light source 130 accommodated in the film hole can enter the switch circuit layer 16 from the sidewall of the first hole 165, so that the switch circuit layer 16 can serve as a light guide plate for guiding the lateral transmission of light. For example, when the first hole 165 is disposed in the second layer 16b or the second layer 16b and the spacer layer 16c, the microstructure 168 of the switch circuit layer 162 is preferably disposed on the lower surface of the second layer 16b or the spacer layer 16c. In one embodiment, when the switch circuit layer 16 extends beyond the rib portion 117 (or, for example, 117a, 117b1, 117b2, 117c of the aforementioned embodiments) of the substrate 110 covering the broken hole (e.g., 113c, 113p), the microstructure 168 of the switch circuit layer 162 can be disposed on the lower surface of the second layer 16b or the spacer layer 16c and overlap the covered broken hole (e.g., 113c, 113p) in the stacking direction.

[0053] In this embodiment, the backlight key 1 further includes a reflective layer 180, and the reflective layer 180 at least partially covers the light source 130. For example, the reflective layer 180 can be disposed in an island form on the upper surface of the switch circuit layer 16 (i.e., the upper surface of the first layer 16a) to cover directly above the light source 130. The reflective layer 220 is preferably formed on the upper surface of the first layer 16a of the switch circuit layer 16 by a reflective material (such as white paint or white ink) and by any suitable means (such as printing). In this way, the light emitted upward by the light source 130 will be reflected downward by the reflective layer 180 twice through the reflective surface 146 and / or the microstructure 144 of the protective layer 140 of the circuit board to scatter upward to improve the uniformity of brightness.

[0054] Figure 6 The top view schematic diagram of the configuration of the upper surface of the backlight circuit board around the light source for another embodiment of the utility model is shown. As shown in Figure 6 The adhesive layer 170 can be an open annular adhesive layer with an adhesive layer gap 173 to provide an exhaust effect for the backlight key 1. For example, the adhesive layer gap 173 can be disposed in one or more regions of the adhesive layer 170. The reflective layer 180 is preferably located within the range of the glue-free area 171, but is not limited thereto. Depending on the actual application, the reflective layer 180 can extend to the adhesive layer 170.

[0055] The backlight circuit board can not only be used as the bottom plate of the key structure, but also can be used as the light source circuit board with the light emitting circuit. Furthermore, the backlight circuit board integrates the light emitting circuit in the bottom plate of the key structure, effectively reduces the overall key thickness, and promotes the thin design. In addition, in the backlight key, the circuit film is used as the switch circuit layer, the light source is accommodated in the film hole of the circuit film, the light guide plate is omitted by the light guide effect of the circuit film, and the thin design is further promoted.

[0056] Of course, the utility model also can have other multiple embodiments, in not departing from the utility model spirit and its essence, the skilled person of the art can make various corresponding changes and deformation according to the utility model, but these corresponding changes and deformation all should belong to the protection scope of the utility model appended claim.

Claims

1. A backlight circuit board to carry a keycap, characterized by The backlight circuit board comprises: a substrate having a plurality of ribs defining a plurality of break holes penetrating through the substrate and a plurality of connectors disposed on the substrate and used to directly or indirectly connect the keycap; a light-emitting line disposed on the substrate and located at the same side of the plurality of connectors, the light-emitting line extending above the plurality of ribs of the substrate; a light source electrically connected to the light-emitting line, the light source disposed above at least one of the plurality of ribs of the substrate, wherein the light source is at least partially vertically corresponding to a non-light-emitting area of the keycap, and a vertical projection of the non-light-emitting area at least partially overlaps with the plurality of ribs of the substrate. The substrate is a non-metallic plate, so that the upper surface of the substrate is an insulating surface; or the substrate comprises a metallic plate and an insulating layer at least partially covering the upper surface of the metallic plate.

2. The backlight circuit board of claim 1, wherein, The backlight circuit board further comprises a switch circuit layer, wherein the switch circuit layer and the light-emitting line are disposed on the same side of the substrate, the switch circuit layer has a switch unit, and a vertical projection of the switch unit does not overlap with the light source.

3. The backlight circuit board of claim 1, wherein, The switch circuit layer has a first hole corresponding to the light source.

4. The backlight circuit board of claim 3, wherein, The switch circuit layer has a second hole corresponding to at least one of the plurality of connectors.

5. The backlight circuit board of claim 4, wherein, The switch circuit layer has a switch circuit electrically connected to the switch unit, and a vertical projection of the switch circuit and the light-emitting line at least partially overlaps with one of the plurality of ribs.

6. The backlight circuit board of claim 3, wherein, The vertical projections of the switch unit and the light source are both located within a range collectively surrounded by the plurality of connectors.

7. The backlight circuit board of claim 3, wherein, The backlight circuit board further comprises a light-absorbing layer, wherein the light-absorbing layer is disposed on the switch circuit layer to define at least one light-transmitting window corresponding to the keycap.

8. The backlight circuit board of claim 3, wherein, The backlight circuit board further comprises a protective layer, wherein the protective layer is disposed on the substrate to cover the light-emitting line, the protective layer has a reflective surface and / or a microstructure located within a vertical projection range of the at least one light-transmitting window.

9. The backlight circuit board of claim 8, wherein, The backlight circuit board further comprises a protective layer, wherein the protective layer is disposed on the substrate to cover the light-emitting line.

10. The backlight circuit board of claim 1, wherein, The protective layer has a reflective surface and a microstructure, or the protective layer has a microstructure that overlaps with at least one of the plurality of ribs of the substrate.

11. The backlight circuit board of claim 9, wherein, The plurality of connectors extend from the substrate to above the light-emitting line.

12. The backlight circuit board of claim 1, wherein, The backlight circuit board comprises:

13. A backlit key, characterized by The backlight circuit board according to any one of claims 1 to 12; and The keycap. The backlight circuit board comprises:

14. A backlit keyboard, characterized by The backlight circuit board according to any one of claims 1 to 12; and The keycap. The backlight circuit board comprises:

15. A backlit key, characterized by The keycap; The circuit board having a light-emitting line, a light source, and a plurality of connectors used to directly or indirectly connect the keycap, the light-emitting line disposed on the upper surface of the circuit board and electrically connected to the light source; The circuit film disposed between the keycap and the circuit board, the circuit film having a film hole for accommodating the light source; and The adhesive layer disposed around the film hole and bonding the circuit board and the circuit film, the adhesive layer and the film hole having a glue-free area therebetween. The keycap has a light-emitting area and a non-light-emitting area, and the light source is at least partially located outside a vertical projection range of the light-emitting area.

16. The backlit key of claim 15, wherein, The circuit film has a switch unit, and a vertical projection of the switch unit does not overlap with the light source.

17. The backlit key of claim 15, wherein, ​ 18. The backlit key of claim 15, wherein, The backlight key further comprises a reflective layer, wherein the reflective layer at least partially covers the light source.

19. The backlit key of claim 15, wherein, The backlight key further comprises a light-absorbing layer, wherein the light-absorbing layer is disposed on the circuit film to define at least one light-transmitting window corresponding to the keycap.

20. The backlit key of claim 19, wherein, The circuit board further has a protective layer covering the light-emitting circuit, the protective layer having a reflective surface and / or a microstructure within the vertical projection range of the at least one light-transmitting window.

21. The backlit key of claim 15, wherein, The circuit board further has a substrate and a protective layer covering the light-emitting circuit, the protective layer having a reflective surface and a microstructure or the protective layer having a microstructure overlapping at least one of the ribs of the substrate.

22. The backlit key of claim 15, wherein, The circuit film is a multi-layer structure, wherein the film hole is a through hole penetrating through the multi-layer structure or a blind hole disposed on at least one layer of the multi-layer structure.

23. The backlit key of claim 22, wherein, The circuit film has a microstructure, and when the film hole is a blind hole disposed on at least one layer of the multi-layer structure, the microstructure is disposed on at least one layer of the multi-layer structure.

24. The backlit key of claim 15, wherein, The adhesive layer is an open ring-shaped adhesive layer having an adhesive layer gap.

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