CN106445218B

CN106445218B - Touch control panel and circuit board thereof

Info

Publication number: CN106445218B
Application number: CN201510503745.4A
Authority: CN
Inventors: 吴建辉; 钟国盟
Original assignee: Elan Microelectronics Corp
Current assignee: Elan Microelectronics Corp
Priority date: 2015-08-06
Filing date: 2015-08-17
Publication date: 2021-11-09
Anticipated expiration: 2035-08-17
Also published as: TW201706784A; TWI574188B; CN106445218A

Abstract

The present invention is a touch panel and its circuit board. The surface of the circuit board has a plurality of sensing electrodes and an electrostatic protection electrode, the electrostatic protection electrode surrounds a fingerprint sensor, and a cover is attached to The surface of the circuit board body, and the cover plate forms an opening corresponding to accommodating the fingerprint sensor; when the cover plate is attached to the circuit board, the center of the opening is aligned with the center of the fingerprint sensor, and the There is a gap between the fingerprint sensor and the opening, the electrostatic protection electrode corresponds to the gap, and the electrostatic protection electrode is used to guide static electricity to a grounding end, so as to prevent the static electricity entering from the gap from destroying the fingerprint sensor and the fingerprint sensor. Sensing electrodes on circuit boards.

Description

Touch control panel and circuit board thereof

Technical Field

The present invention relates to a touch pad, and more particularly, to a touch pad having a fingerprint sensor.

Background

Fig. 7 and 8 are schematic diagrams and cross-sectional views of a touch panel 90 with a fingerprint sensor, which mainly includes a circuit board 91 and a cover plate 92, wherein a fingerprint sensor 93 is mounted on a surface of the circuit board 91 for sensing and identifying a fingerprint of a user, the cover plate 92 forms an opening 94 corresponding to the fingerprint sensor 93, and after the cover plate 92 is attached to the surface of the circuit board 91, the opening 94 can accommodate the fingerprint sensor 93 and expose the surface of the fingerprint sensor 93 for the user to operate.

In the process of attaching the cover plate 92, the positioning marks preset on the periphery of the cover plate 92 and the positioning marks on the periphery of the circuit board 91 are used as alignment references, and when the positioning marks of the two are aligned, the two are bonded. However, slight position errors may occur when the fingerprint sensor 93 is soldered to the circuit board 91, and the opening 94 may be formed on the cover 92 in a shifted manner, so that the fingerprint sensor 93 may not be accommodated in the opening 94 when the cover 92 is bonded to the circuit board 91.

To prevent the fingerprint sensor 93 from being inserted into the opening 94, the opening 94 with a larger size may be designed to compensate for the error deviation. However, when the opening 94 is enlarged, a significant gap is formed between the fingerprint sensor 93 and the opening 94. One way to solve the gap is to inject glue into the gap between the fingerprint sensor 93 and the opening 94 to form a rubber ring 95 as shown in fig. 8, but the disadvantage is that the appearance of the finished product is not good and the glue protrudes from the surface of the cover 92 to affect the operation touch of the user.

Fig. 9 shows another way of filling the gap by directly inserting a ring cover 96 into the gap, wherein the top of the ring cover 96 protrudes from the surface of the cover plate 92. When the ring cover 96 is used to fill the gap, the size of the opening 94 must be increased in order to ensure that the gap has a sufficient width to fill the gap with the ring cover 96. The disadvantage is that the additional cost of the ring cover 96 is increased, and the surface of the ring cover 96 still protrudes from the surface of the cover plate 92, which may affect the operation of the user and may hinder the appearance of the touch pad 90.

Disclosure of Invention

The invention provides a touch pad, which does not need to be additionally provided with a rubber ring or a ring cover, has the function of electrostatic protection and maintains a smooth surface.

To achieve the above object, the touch panel of the present invention comprises:

a circuit board, comprising:

the circuit board body comprises a plurality of induction electrodes for touch operation;

a fingerprint sensor installed on the surface of the circuit board body; and

the electrostatic protection electrode is formed on the surface of the circuit board body and is arranged around the fingerprint sensor, and the electrostatic protection electrode is electrically connected with the grounding end of the circuit board; and

the cover plate is attached to the surface of the circuit board body, an opening corresponding to the fingerprint sensor is formed in the cover plate, the opening is used for accommodating the fingerprint sensor, a gap is formed between the fingerprint sensor and the opening, and the electrostatic protection electrode corresponds to the gap and can protect elements such as the fingerprint sensor and the circuit board body from being damaged by static electricity.

When the cover plate is attached to the circuit board body, the center of the opening is aligned to the center of the fingerprint sensor, and the fingerprint sensor can be ensured to be contained in the opening without any filler in the gap by a center alignment mode, so that the whole touch control plate has an attractive and flat surface.

Drawings

FIG. 1: the invention is a three-dimensional exploded view.

FIG. 2: the front side of the circuit board of the invention is schematically shown.

FIG. 3: the bottom surface of the circuit board is schematically shown.

FIG. 4: a partial cross-sectional view of the present invention.

FIG. 5: the invention discloses a partial enlarged view of a fingerprint sensor.

FIG. 6A: the invention discloses a schematic alignment diagram of a cover plate and a circuit board body.

FIG. 6B: the invention is a schematic diagram after the cover plate and the circuit board body are aligned.

FIG. 7: the partial appearance of the existing touch pad is schematically shown.

FIG. 8: schematic diagram of a conventional touch pad.

FIG. 9: schematic diagram of a conventional touch pad.

Description of the main symbols:

10 circuit board 11 circuit board body

12 induction electrode 13 electrostatic protection electrode

131 conductor line

14 first ground ring 15 second ground ring

16 ground pad 17 connection pad

18 conductive via

20 fingerprint sensor 30 cover

31 opening 40 slit

90 touch pad 91 circuit board

92 cover 93 fingerprint sensor

94 opening 95 rubber ring

96 ring covers.

Detailed Description

Referring to fig. 1 and 2, the touch panel according to the present invention may be a capacitive touch panel, which includes a circuit board 10, a fingerprint sensor 20 and a cover plate 30, wherein the circuit board 10 has a circuit board body 11, and a plurality of sensing electrodes 12 are disposed on a surface of the circuit board body for performing touch operation. An electrostatic discharge protection electrode 13 is formed at a corner of the surface of the circuit board body 11, the electrostatic discharge protection electrode 13 is formed by a conductor (e.g. metal) circuit, in this embodiment, the electrostatic discharge protection electrode 13 is a closed ring, and in other embodiments, the configuration of the electrostatic discharge protection electrode 13 may be in other shapes. A plurality of connection pads 17 are provided in the region surrounded by the electrostatic protection electrode 13. The fingerprint sensor 20 is an Integrated Circuit (IC) having a plurality of electrical contacts, and the fingerprint sensor 20 is mounted on the surface of the circuit board body 11, and the electrical contacts are electrically connected to the connecting pads 17. The electrostatic protection electrode 13 is disposed around the fingerprint sensor 20. The electrostatic discharge protection electrode 13 is electrically connected to a ground terminal of the circuit board body 11, and how the electrostatic discharge protection electrode 13 is electrically connected to the ground terminal will be further described below.

In the embodiment shown in fig. 1, the periphery of the surface of the circuit board body 11 is provided with a first grounding ring 14, the first grounding ring 14 is composed of conductor (e.g. metal) lines, and the electrostatic protection electrode 13 is electrically connected with the first grounding ring 14 through a conductor (e.g. metal) line 131 formed on the surface of the circuit board body 11. Referring to fig. 3, a second ground ring 15 is also formed on the periphery of the bottom surface of the circuit board body 11, the second ground ring 15 is electrically connected to the first ground ring 14, for example, a plurality of conductive vias 18 may be formed on the periphery of the circuit board body 11, and two ends of each conductive via 18 are electrically connected to the first ground ring 14 and the second ground ring 15, respectively. The bottom surface of the circuit board body 11 has at least one grounding pad 16, the grounding terminal includes the grounding pad 16, in this embodiment, there are two grounding pads 16, the grounding pad 16 is electrically connected to the second grounding ring 15, wherein the grounding pad 16 can be electrically connected to a grounding terminal (ground) of an electronic device, such as a notebook computer. With the above structure, the electrostatic discharge protection electrode 13 is electrically connected to the grounding pad 16 through the conductive line 131, the first grounding ring 14, the conductive via 18 and the second grounding ring 15, thereby achieving the grounding effect.

However, the present invention is not limited to the foregoing structure, and the esd protection electrode 13 may be electrically connected to the grounding pad 16 by other methods. In one embodiment, the electrostatic discharge protection electrode 13 is electrically connected to the grounding pad 16 through a wiring of the circuit board body 11, which may be a conductive wire formed inside or on the surface of the circuit board body 11. In another embodiment, the ESD protection electrode 13 is connected to the first ground ring 14, and the first ground ring 14 is electrically connected to the ground pad 16 through the conductive via 18 or a conductive line inside the circuit board body 11.

As further shown in fig. 4, the cover plate 30 is attached to the surface of the circuit board body 11, the cover plate 30 forms an opening 31 corresponding to the fingerprint sensor 20, the opening 31 is used for accommodating the fingerprint sensor 20, after the cover plate 30 is attached, the fingerprint sensor 20 is accommodated in the opening 31, an annular gap 40 is formed between the fingerprint sensor 20 and the periphery of the opening 31, and the electrostatic protection electrode 13 on the circuit board body 11 corresponds to the gap 40, as shown in fig. 5.

According to an embodiment of the present invention, when the cover 30 is attached to the circuit board body 11, the center a of the opening 31 is aligned with the center B of the fingerprint sensor 20 (as shown in fig. 6A), and after the two centers A, B are aligned, the cover 30 is adhered to the surface of the circuit board body 11 (as shown in fig. 6B) to complete the assembly of the touch panel. Different from the prior art that the positioning marks on the edges of the circuit board body and the cover plate are used for alignment, the present invention ensures that the fingerprint sensor 20 is always accommodated in the opening 31 by the above central alignment method, therefore, the size of the opening 31 only needs to be slightly larger than the size of the fingerprint sensor 20, and the size of the opening does not need to be increased intentionally, so that the width of the gap 40 can be reduced from more than 1mm to 0.1mm compared with the prior art. After the attachment is completed, the center a of the opening 31 corresponds to the center B of the fingerprint sensor 20, and the width of the gap 40 around the fingerprint sensor 20 is substantially equal.

Compared with the existing touch control panel, the touch control panel of the invention at least has the following advantages:

firstly, the appearance is smooth: the width of the gap 40 between the opening 31 of the cover 30 and the fingerprint sensor 20 is reduced, and there is no need to fill a rubber ring or ring cover into the gap 40, so that there is no significant protrusion around the fingerprint sensor 20, and the gap is substantially kept flat with the surface of the cover 30, thereby improving the appearance of the touch panel.

Secondly, the cost is reduced and the assembly process is simplified: since there is no need to fill the gap 40 with a rubber ring or to put a ring cover, the component cost can be reduced and the assembly process can be simplified.

Thirdly, providing a comfortable operating surface: the present invention can reduce the width of the gap 40, and the protruding rubber ring or ring cover is not disposed around the fingerprint sensor 20, so that the boundary between the fingerprint sensor 20 and the cover plate 30 can present a substantially flat surface, and when the user operates the touch pad, the user can have a smooth operation touch feeling no matter whether the user touches the fingerprint sensor 20 or the cover plate 30.

Fourthly, Electrostatic (ESD) protection: the electrostatic protection electrode 13 is disposed around the fingerprint sensor 20, and the static electricity entering from the gap 40 is conducted to the ground pad 16 through the electrostatic protection electrode 13. Therefore, the fingerprint sensor 20 and the sensing electrode 12 on the circuit board body 11 can be protected.

In one embodiment, the side of the fingerprint sensor 20 is exposed by a metal layer (e.g., copper) belonging to a carrier for carrying the chip inside the fingerprint sensor 20 and transmitting signals between the chip and the electrical contacts under the fingerprint sensor 20, and the metal layer is used to fabricate the circuit for transmitting signals. In this embodiment, an insulating layer is coated on the exposed metal layer, i.e. the side of the fingerprint sensor 20, so as to prevent static electricity from entering the metal layer and damaging the fingerprint sensor 20.

Although the present invention has been described with reference to the above preferred embodiments, it should be understood that various changes and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention.

Claims

1. A touch panel, characterized in that, comprising:

A circuit board containing:

a circuit board body, including a plurality of sensing electrodes for touch operation;

a fingerprint sensor mounted on the surface of the circuit board body, the fingerprint sensor is an integrated circuit; and

an electrostatic protection electrode formed on the surface of the circuit board body and disposed around the fingerprint sensor, the electrostatic protection electrode is electrically connected to a ground terminal of the circuit board body; and

a cover plate attached to the surface of the circuit board body, the cover plate forms a pair of openings for the fingerprint sensor, the opening is used for accommodating the fingerprint sensor, wherein the fingerprint sensor and the opening There is a gap between them, and the electrostatic protection electrode corresponds to the gap;

Wherein, the static electricity entering from the gap will be conducted to the ground terminal through the static electricity protection electrode.

2 . The touch panel of claim 1 , wherein the center of the opening is aligned with the center of the fingerprint sensor. 3 .

3 . The touch panel of claim 1 , wherein the circuit board body has a bottom surface opposite to the surface, the ground terminal comprises at least one ground pad disposed on the bottom surface, and the electrostatic protection electrode is electrically connected to 3 . to this ground pad.

4 . The touch panel of claim 3 , wherein the circuit board body has a first ground ring surrounding the periphery of the surface and a second ground ring surrounding the periphery of the bottom surface, the first ground ring The second grounding ring is electrically connected through a conductive through hole, the first grounding ring and the second grounding ring are electrically connected to the grounding pad, and the electrostatic protection electrode is electrically connected to the first grounding ring.

5 . The touch panel of claim 3 , wherein the circuit board body further has a first ground ring surrounding the periphery of the surface, and the first ground ring is electrically connected to the ground pad through conductive through holes. 6 . , the electrostatic protection electrode is electrically connected to the first ground ring.

6 . The touch panel of claim 3 , wherein the electrostatic protection electrode is electrically connected to the ground pad through a wiring on the circuit board body. 7 .

7 . The touch panel of claim 4 , wherein the electrostatic protection electrode and the first ground ring are electrically connected through a conductor circuit. 8 .

8 . The touch panel of claim 1 , further comprising an insulating glue coated on the side of the fingerprint sensor. 9 .