TW202133031A - Fingerprint sensing apparatus - Google Patents

Abstract

A fingerprint sensing apparatus is provided, which includes a substrate, a fingerprint sensor, a metal middle frame and a supporting component. The fingerprint sensor is disposed on the substrate, and the metal middle frame has an opening. The supporting component is assembled on the opening of the metal middle frame, and the supporting component is disposed on the substrate. The fingerprint sensor is below the opening. A metal layer is formed on a outer surface of the supporting component, and the metal layer is electrically conducted to the metal middle frame.

Description

Fingerprint sensing device

The present invention relates to a fingerprint sensing device, and particularly relates to an ESD protection structure of the fingerprint sensing device.

As the screens of mobile electronic devices become larger and larger, the space left for fingerprint sensing elements under the non-display area is gradually restricted. In this case, in order to bring a more convenient user experience to users, an under-screen fingerprint sensing solution with an optical fingerprint sensor installed at the bottom of the screen is increasingly being valued. It can be seen that electrostatic discharge (ESD) is one of the causes of damage to the fingerprint sensor under the display panel. Therefore, the fingerprint sensor module generally incorporates an electrostatic protection design to prevent electrostatic discharge damage. For example, antistatic components (such as transient voltage suppressors (TVS)) can be provided on the I/O pins of the fingerprint sensor. However, the existing antistatic components may cause a latch-up effect, so that the fingerprint sensor needs to be reset to operate normally. In addition, the addition of anti-static components can only protect the electrostatic discharge from the I/O pins of the fingerprint sensor, and cannot prevent the electrostatic discharge generated by the fingers or other objects above the display panel.

In view of this, the present invention provides a fingerprint sensor device, which has a supporting structure that helps to improve the anti-static discharge capability, so as to prevent the fingerprint sensor from being damaged.

An embodiment of the present invention provides a fingerprint sensing device, which includes a substrate, a fingerprint sensor, a metal middle frame, and a support. The fingerprint sensor is disposed on the substrate, and the metal middle frame has an opening. The support is assembled at the opening of the metal middle frame and fixed on the substrate. The fingerprint sensor is located under the opening. The metal layer is formed on the outer surface of the support, and the metal layer is electrically connected to the metal middle frame.

Based on the above, in the embodiment of the present invention, the fingerprint sensor is placed in the accommodating space of the support with the metal layer on the outer surface. Since the metal layer on the outer surface of the support is electrically connected to the metal middle frame, static electricity can be guided to the metal middle frame, thereby preventing electrostatic discharge from damaging the fingerprint sensor.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

In order to make the content of the present invention more comprehensible, the following embodiments are specifically cited as examples on which the present invention can indeed be implemented. In addition, wherever possible, elements/components/steps with the same reference numbers in the drawings and embodiments represent the same or similar components.

It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element, or Intermediate elements can also be present. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there are no intervening elements. As used herein, "connected" can refer to physical and/or electrical connection. Furthermore, "electrically connected" or "coupled" may mean that there are other elements between two elements.

1, the fingerprint sensor device 100 provides an under-screen fingerprint recognition function. The user's finger can press the glass cover above the display panel 150 so that the fingerprint sensor 110 under the display panel 150 can obtain a fingerprint image. The display panel 150 may be a display panel with self-luminous display elements, such as an Organic Light-Emitting Diode (OLED) display panel, but the invention is not limited thereto. When performing fingerprint sensing, the user places a finger on the display panel 150, and the display panel 150 emits an illuminating light beam to illuminate the finger, and the reflected light beam generated by the reflection of the finger is transmitted to the fingerprint sensor 110 for fingerprint sensing. Measurement. The fingerprint sensing device 100 is, for example, a smart phone, a panel, a game console, or other electronic devices with an optical under-screen fingerprint recognition function, which is not limited by the present invention. In one embodiment, the fingerprint sensing device 100 includes a substrate 140, a fingerprint sensor 110, a metal middle frame 120, and a support 130.

The fingerprint sensor 110 may include a sensing pixel array composed of a plurality of sensing pixels, and each of the sensing pixels includes at least one photodiode for photoelectric conversion. For example, the fingerprint sensor 110 may include a complementary metal oxide semiconductor (CMOS) sensor, a charge coupled device (CCD) sensor, or other suitable image sensors. In an embodiment, the fingerprint sensor 110 may further include other optical elements, such as lenses, collimators, filter layers, etc., disposed above the sensing pixel array, which is not limited by the present invention. The fingerprint sensor 110 can be implemented as a chip or a chip with optical elements disposed on the chip, which is not limited by the present invention. In addition, the present embodiment takes one fingerprint sensor 110 as an example for description, but the present invention does not limit the number of fingerprint sensors.

The fingerprint sensor 110 is disposed on the substrate 140. The substrate 110 is, for example, a printed circuit board (PCB), or a supporting base plate and a flexible printed circuit (FPC) disposed thereon. The fingerprint sensor 110 can be electrically connected to the circuit layer of the substrate 140, so that the fingerprint sensor 110 can be electrically connected to an external circuit through the substrate 140. In this way, the fingerprint sensor 110 can provide fingerprint sensing data to other processing units of the fingerprint sensing device 100.

The metal middle frame 120 is a frame for supporting the display panel 150 in the fingerprint sensing device 100. In addition, the metal middle frame 120 can also be used to carry various internal device components. The above-mentioned device components can be a motherboard, a camera device, a microphone, or various sensors, and so on. In order to allow the fingerprint sensor 110 to receive the light beam reflected by the finger, the metal middle frame 120 has an opening 125 and the fingerprint sensor 110 is located under the opening 125. The light beam reflected by the finger can be transmitted to the fingerprint sensor 110 through the opening 125.

The support 130 is assembled on the metal middle frame 120 and aligned with the opening 125. In addition, the support 130 is fixed on the substrate 140 so that the fingerprint sensor 110 on the substrate 140 is located in the accommodating space of the support 130. Based on this, the substrate 140 can be fixedly connected to the metal middle frame 120 by the support 130, so that the fingerprint sensor 110 is fixedly disposed under the display panel 150. In one embodiment, at least a part of the support 130 is located in the opening 125, and the support 130 assembled on the metal middle frame 120 can be used to support the display panel 150 at the same time. The support 130 may be made of resin or other opaque materials.

It should be particularly noted that the metal layer C1 is formed on the outer surface of the support 130, and the metal layer C1 is electrically connected to the metal middle frame 120. The metal layer C1 can be an electroplated metal layer or a conductive tape. In other words, the metal layer C1 can be formed by electroplating metal on the outer surface of the support 130 or bonding a conductive tape. In addition, the present invention does not limit the covering shape of the metal layer C1 covering the outer surface of the support 130, and it can be set according to actual applications and requirements. Since the metal layer C1 is electrically connected to the metal middle frame 120, static electricity can be guided to the metal middle frame 120 to release static electricity, and the fingerprint sensor 110 can achieve the function of electrostatic discharge protection. In this way, the fingerprint sensor 110 is not easily damaged by electrostatic discharge and loses its performance. It is worth mentioning that, in one embodiment, the resistance value of the metal layer C1 may be higher than the resistance value of the metal middle frame 120. Based on this, it is more beneficial to guide static electricity from the metal layer C1 to the metal middle frame 120.

In one embodiment, when the support 130 is assembled on the metal middle frame 120, the metal layer C1 can directly contact the metal middle frame 120 to be electrically connected. Alternatively, in one embodiment, the supporting member 130 may be fixed to the metal middle frame 120 through the conductive fixing member, and the conductive fixing member is electrically connected to the metal layer C1, that is, the metal layer C1 may be connected to the middle frame through the conductive fixing member. 120 is electrically conductive. The conductive fixing member may include a metal lock attachment, conductive glue or solder balls.

As shown in FIG. 1, the supporting member 130 can be fixed to the metal middle frame 120 through a metal lock attachment 21 (such as a screw), so that the metal layer C1 contacting the metal lock attachment 21 and the metal middle frame 120 are electrically connected. Correspondingly, the metal middle frame 120 and the support 130 are respectively provided with positioning holes suitable for allowing the metal lock accessory 21 to pass through. Alternatively, FIG. 2A is a schematic diagram of a support member fixed to a metal middle frame through an adhesive layer according to an embodiment of the present invention. As shown in FIG. 2A, the support 130 can be adhered to the metal middle frame 120 through the conductive glue 22, so that the metal layer C1 in contact with the conductive glue 22 and the metal middle frame 120 are electrically connected. Or, FIG. 2B is a schematic diagram of a support member fixed to a metal middle frame through soldering according to an embodiment of the present invention. As shown in FIG. 2B, the support 130 can be attached to the metal middle frame 120 through the solder balls 23, so that the metal layer C1 in contact with the solder balls 23 is electrically connected to the metal middle frame 120.

1 again, in this embodiment, the support 130 may include a lens fixing portion 131 and an abutting portion 132, and the lens fixing portion 131 is connected to the abutting portion 132. The lens L1 for collecting the light beam is installed in the lens fixing part 131, and the lens fixing part 131 is located in the opening 120 of the metal middle frame 120. The lens L1 can be fixed on the lens fixing portion 131 via an adhesive layer. The outer surface of the supporting portion 130 includes the first surface S1 of the lens fixing portion 131. In this embodiment, the local metal layer C1 is formed on the first surface S1 of the lens fixing portion 131 and is located between the lens fixing portion 131 and the display panel 150. Between the bottom surface. Thereby, the part of the metal layer C1 covering the first surface S1 can be used to protect the electrostatic discharge caused by the fingers or other objects above the display panel 150.

3 is a schematic cross-sectional view of a fingerprint sensing device according to an embodiment of the invention. Referring to FIG. 3, the configuration of the substrate 140, the fingerprint sensor 110, the metal middle frame 120, and the support 130 of this embodiment is similar to that of the embodiment of FIG. 1, and the main differences between the two are as follows. In the embodiment of FIG. 2, the substrate 140 may further include an electrostatic protection layer 31 and a conductive pad 32.

In this embodiment, the static electricity protection layer 31 may be a metal layer formed on the upper surface of the substrate 140, such as a metal wiring or other patterned metal layer. In addition, in other embodiments, the static electricity protection layer 31 further includes a circuit layer in the substrate 140 or a metal layer formed on the lower surface of the substrate 140. The static electricity protection layer 31 is electrically connected to the metal layer C1. The static electricity protection layer 31 on the substrate 140 may directly contact the metal layer C1 to be electrically connected, or the static electricity protection layer 31 on the substrate 140 may be electrically connected to the metal layer C1 through a conductive adhesive material. The static electricity protection layer 31 on the substrate 140 can guide static electricity to the metal layer C1, and the metal layer C1 can lead the static electricity to the metal middle frame 120 to be released. Thereby, the electrostatic protection layer 31 on the substrate 140 can effectively prevent the fingerprint sensor 110 from being damaged by electrostatic discharge. It is worth mentioning that, in one embodiment, the resistance value of the electrostatic protection layer 31 is higher than the resistance value of the metal layer C1. Based on this, it is more beneficial to guide static electricity from the static electricity protection layer 31 to the metal layer C1.

In this embodiment, the supporting member 130 may be fixed on the substrate 140 through the adhesive layer, that is, the abutting portion 132 of the supporting member 130 may be fixed on the substrate 140 through the adhesive layer. The abutting portion 132 includes a bottom surface and a top surface, and the bottom surface of the abutting portion 132 is opposite to the top surface of the abutting portion 132. The bottom surface of the contact portion 132 faces the substrate 140, and the top surface of the contact portion 132 faces the metal middle frame 120. It should be noted that the adhesive layer used to bond the abutting portion 132 and the substrate 140 may be a conductive material or a non-conductive material. In detail, FIGS. 4A and 4B are schematic diagrams of a support member fixed on a substrate through an adhesive layer according to an embodiment of the present invention. In the embodiment shown in FIG. 4A, the partial metal layer C1 is formed on the bottom surface S2 of the abutting portion 132 and is located between the abutting portion 132 and the substrate 140. The local metal layer C1 can directly contact the electrostatic protection layer 31 on the substrate 140, and the contact portion 132 will be fixed on the substrate 140 through the adhesive layer 34 of conductive or non-conductive material. In addition, in the embodiment shown in FIG. 4B, the metal layer C1 is not extended and formed on the bottom surface S2 of the contact portion 132. The abutting portion 132 is fixed on the substrate 140 through the adhesive layer 35 made of conductive material, and the metal layer C1 can be electrically connected to the electrostatic protection layer 31 on the substrate 140 through the adhesive layer 35 made of conductive material.

On the other hand, in this embodiment, the conductive pad 32 on the substrate 140 is disposed under the fingerprint sensor 110 and is electrically connected to the fingerprint sensor 110. The fingerprint sensor 110 can be connected to a circuit on the substrate 140 via the conductive pad 32. It is worth mentioning that, in one embodiment, the resistance value of the conductive pad 32 is higher than the resistance value of the electrostatic protection layer 31. Based on this, static electricity is easier to be guided by the static electricity protection layer 31 to the metal layer C1, so as to prevent static electricity from entering the fingerprint sensor 110 via the conductive pad 32 and damaging the fingerprint sensor 110.

FIG. 5 is a schematic cross-sectional view of a fingerprint sensing device according to an embodiment of the invention. Referring to FIG. 5, the configuration of the substrate 140, the fingerprint sensor 110, the metal middle frame 120, and the support 130 of this embodiment is similar to that of the embodiment of FIG. 1, and the main differences are as follows. In the embodiment of FIG. 5, the partial metal layer C1 may be formed on the second surface S3 of the lens fixing portion 121. The second surface S3 is opposite to the lens L1, and the lens L1 can be attached to the local metal layer C1 on the second surface S3 through an adhesive layer. The local metal layer C1 formed on the second surface S3 can enhance the ability to resist electrostatic discharge. As shown in FIG. 6A, FIG. 6A is a schematic diagram of a lens fixed on a support through an adhesive layer according to an embodiment of the present invention. The adhesive layer 61 is made of a conductive material, the adhesive layer 61 is coated on the second surface S3 of the lens fixing portion 131, and the adhesive layer 61 is electrically connected to the metal layer C1. The adhesive layer 61 of conductive material can induce static electricity to the metal layer C1, and the metal layer C1 can induce static electricity to release the metal middle frame 120. In this way, the adhesive layer 61 made of conductive material can also enhance the ability to resist electrostatic discharge.

However, in other embodiments, the metal layer C1 may not extend between the lens fixing portion 131 and the lens L1. As shown in FIG. 6B, FIG. 6B is a schematic diagram of a lens fixed on a support through an adhesive layer according to an embodiment of the present invention. The adhesive layer 62 made of conductive material is located between the second surface S3 of the lens fixing portion 131 and the lens L1. Although the metal layer C1 is not extended and formed on the lens fixing portion 131 and the lens L1, the adhesive layer 62 made of conductive material is in contact with the metal layer C1 and is electrically connected to the metal layer C1. Similarly, the adhesive layer 62 of conductive material can also induce static electricity to the metal layer C1, and the metal layer C1 can induce static electricity to cause the metal middle frame 120 to be released. Thereby, the adhesive layer 62 of conductive material can also enhance the anti-static discharge ability.

In summary, in the embodiment of the present invention, the fingerprint sensor can be assembled on the metal middle frame by the support, so that the fingerprint sensor can be stably arranged under the display panel, so that the fingerprint sensor device Can provide fingerprint recognition function under the screen. The fingerprint sensor is placed in the accommodating space of the support with a metal layer on the outer surface. The metal layer on the outer surface of the support is electrically connected to the metal middle frame, so that static electricity can be guided to the metal middle frame, thereby preventing electrostatic discharge events from damaging the fingerprint sensor. In addition, the metal layer can be formed between the display panel and the support, so that a part of the metal layer can be located above the fingerprint sensor to prevent the fingerprint sensor from being damaged by ESD from above the display panel.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions recorded in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the technical solutions of the embodiments of the present invention. Scope.

100: Fingerprint sensing device 110: Fingerprint sensor 120: Metal middle frame 125: open 130: Support 131: Lens fixing part 132: Abutment 140: substrate 150: display panel L1: lens C1: Metal layer 21: Metal lock accessories 22: Adhesive layer 23: Solder ball 31: Electrostatic protection layer 32: Conductive pad S1: First surface S2: bottom surface S3: second surface 34, 35: Adhesive layer 61, 62: Adhesive layer

FIG. 1 is a schematic cross-sectional view of a fingerprint sensing device according to an embodiment of the invention. 2A is a schematic diagram of a support member fixed to a metal middle frame through an adhesive layer according to an embodiment of the present invention. 2B is a schematic diagram of a support member fixed to a metal middle frame through soldering according to an embodiment of the present invention. 3 is a schematic cross-sectional view of a fingerprint sensing device according to an embodiment of the invention. 4A and 4B are schematic diagrams of a support member fixed on a substrate through an adhesive layer according to an embodiment of the present invention. FIG. 5 is a schematic cross-sectional view of a fingerprint sensing device according to an embodiment of the invention. 6A and 6B are schematic diagrams of a lens fixed on a support through an adhesive layer according to an embodiment of the present invention.

100: Fingerprint sensing device

110: Fingerprint sensor

120: Metal middle frame

125: open

130: Support

131: Lens fixing part

132: Abutment

140: substrate

150: display panel

L1: lens

C1: Metal layer

21: Metal lock accessories

Claims (10)

A fingerprint sensing device includes: A substrate; A fingerprint sensor arranged on the substrate; A metal middle frame with an opening; and A support member assembled at the opening of the metal middle frame and fixed on the substrate, wherein the fingerprint sensor is located below the opening, a metal layer is formed on the outer surface of the support member, and the metal The layer is electrically connected to the metal middle frame. The fingerprint sensing device according to claim 1, wherein the metal layer is an electroplated metal layer or a conductive tape. The fingerprint sensing device according to claim 1, wherein the resistance value of the metal layer is higher than the resistance value of the metal middle frame. The fingerprint sensing device according to claim 1, wherein the supporting member is fixed on the metal middle frame through a conductive fixing member, and the conductive fixing member is electrically connected to the metal layer. The fingerprint sensing device according to claim 1, wherein the substrate includes an electrostatic protection layer, and the electrostatic protection layer is electrically connected to the metal layer. The fingerprint sensing device according to claim 5, wherein the resistance value of the static electricity protection layer is higher than the resistance value of the metal layer. The fingerprint sensing device according to claim 6, wherein the substrate includes a conductive pad, the conductive pad is disposed under the fingerprint sensor to be electrically connected to the fingerprint sensor, and the resistance value of the conductive pad is higher than The resistance value of the electrostatic protection layer. The fingerprint sensing device according to claim 1, wherein the support includes a lens fixing portion located in the opening of the metal middle frame, and a lens is fixed to the lens fixing portion via an adhesive layer Above, the metal layer is formed on the first surface of the lens fixing portion and located between the lens fixing portion and the bottom surface of a display panel. The fingerprint sensing device according to claim 8, wherein the adhesive layer is made of conductive material, the adhesive layer is coated on the second surface of the lens fixing portion, and the adhesive layer is electrically connected to the metal layer. The fingerprint sensing device according to claim 8, wherein the supporting member further includes an abutting portion, the lens fixing portion is connected to the abutting portion, and the abutting portion is fixed on the substrate via another adhesive layer The metal layer is formed on the bottom surface of the abutting portion and is located between the abutting portion and the substrate.

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