TWI756779B - Electronic device - Google Patents

Abstract

An electronic device including a fingerprint sensing module, a display panel and a middle frame is provided. The fingerprint sensing module is adapted to sense the sensing light beam reflected by a finger. The display panel is disposed on the fingerprint sensing module, and is adapted to provide an illuminating light beam to the finger to reflect the sensing light beam. The middle frame is disposed between the fingerprint sensing module and the display panel. The middle frame has a first surface, a second surface opposite to each other, and a light entrance. The first surface faces the display panel, the second surface faces the fingerprint sensing module. The sensing light beam passes through the light entrance to be transmitted to the fingerprint sensing module, wherein the first surface includes an annular groove recessed toward the second surface, and the annular groove has a distance from the light entrance.

Description

electronic device

The present invention relates to an electronic device, and more particularly, to an electronic device with a fingerprint sensing module.

In a conventional electronic device with an ultra-thin fingerprint module, during fingerprint signal sensing, the structure of the middle frame is likely to reflect part of the light, causing the light to enter the sensing module, so that the light and the fingerprint signal are simultaneously imaged. In this way, the sensed fingerprint signal will be noisy. Therefore, how to avoid the reflection of light back to the sensing module due to the structure of the middle frame is a goal to be devoted to in the art.

The present invention provides an electronic device, which can avoid reflecting stray light to a fingerprint sensing module, thereby preventing the fingerprint sensing module from sensing a noise light signal and effectively improving the fingerprint sensing effect.

The invention provides an electronic device including a fingerprint sensing module, a display panel and a middle frame. The fingerprint sensing module is suitable for sensing the sensing beam reflected by the finger. The display panel is arranged on the fingerprint sensing module, and is suitable for providing illumination beams to the finger for reflection out the sensing beam. The middle frame is disposed between the fingerprint sensing module and the display panel. The middle frame has opposite first surfaces, second surfaces and light entrances. The first side faces the display panel, and the second side faces the fingerprint sensing module. The sensing beam is transmitted to the fingerprint sensing module through the light entrance, wherein the first surface includes an annular groove concave toward the second surface, and the annular groove has a distance from the light entrance.

Based on the above, in the electronic device of the present invention, through the annular groove design, the middle frame can reduce the reflection of stray light to the fingerprint sensing module, thereby preventing the fingerprint sensing module from sensing the noise light signal and effectively improving the Fingerprint sensing effect.

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, the following embodiments are given and described in detail with the accompanying drawings as follows.

10: Electronics

20: Fingers

50: Fingerprint sensor module

52: circuit board

54: Photosensitive element

56: Optical module

60: Display panel

100: Middle frame

B1: The first included angle

B2: Second included angle

D: distance

G: Annular groove

L1: Lighting beam

L2: Sensing beam

L3: Stray Light

P: light entrance

S1: The first side

S11: The first annular slope

S12: Second annular slope

S2: Second side

FIG. 1 is a schematic cross-sectional view of an electronic device according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a middle frame of the electronic device of FIG. 1 .

FIG. 3 is an enlarged schematic view of an area A in the electronic device of FIG. 1 .

Please refer to Figure 1. This embodiment provides an electronic device 10 including a fingerprint sensing module 50 , a display panel 60 and a middle frame 100 . The display panel 60 is suitable for providing the illumination light beam L1 to the finger 20 to reflect the sensing light beam L2 , and the fingerprint sensing module 50 is disposed under the display panel 60 and is suitable for sensing the sensing light beam reflected by the finger 20 L2. In other words, the electronic device 10 of this embodiment is an off-screen fingerprint identification device, such as a smart phone, a tablet computer, a notebook computer, or a touch-sensitive display device, etc. The present invention is not limited thereto. In this embodiment, the fingerprint sensing module 50 is an ultra-thin structure, and its thickness is only about 300 microns, so it can be applied to a thin electronic device 10 .

In this embodiment, the fingerprint sensing module 50 includes a circuit board 52 , a photosensitive element 54 and an optical module 56 . The circuit board 52 is used to carry the photosensitive element 54 and supply power. The circuit board 52 is, for example, a flexible circuit board, and the photosensitive element 54 is fixed on the circuit board 52 in an adhesive manner. For example, the fingerprint sensing module 50 may further include an adhesive layer, which is connected to the bottom side of the photosensitive element 54 and the circuit board 52, but the invention is not limited thereto. In addition, in some embodiments, the photosensitive element 54 can also be encapsulated to enhance the structural strength of the photosensitive element 54 on the circuit board 52 by using a packaging material.

The photosensitive element 54 is disposed on the circuit board 52 and has a photosensitive surface. For example, the photosensitive element 54 includes a plurality of sensing units. The photosensitive element 54 is, for example, a complementary metal oxide semiconductor (CMOS) image sensor, and the sensing unit is a sensing pixel in these image sensor chips. However, in other embodiments, the photosensitive element 54 may also be an image sensor such as a charge coupled device (CCD), and the present invention does not limit the type of the photosensitive element 54 in the fingerprint sensing module 50 . In some embodiments, a filter or a layer of filter material may be configured on the photosensitive element 54 to filter out the infrared light transmitted to the photosensitive element 54 from the outside, so as to improve the sensing effect.

The optical module 56 is disposed on the photosensitive element 54 and is composed of at least one lens or other optical elements. For example, in this embodiment, the optical module 56 is, for example, It includes a combination of one or more optical lenses with diopter, for example, various combinations of non-planar lenses including biconcave lenses, biconvex lenses, meniscus lenses, convex-concave lenses, plano-convex lenses, and plano-concave lenses. In one embodiment, the optical module 56 may further include an array lens to improve the uniformity of transmitting incident light. The present invention does not limit the type and type of the optical module 56 .

The display panel 60 is disposed on the fingerprint sensing module 50 . In this embodiment, the display panel 60 is, for example, an organic light-emitting diode (OLED) display panel. However, in other embodiments, the display panel 60 can also be a liquid crystal display panel or other suitable display panels, and the present invention is not limited thereto.

Please also refer to Figure 1 to Figure 3. The middle frame 100 is disposed between the fingerprint sensing module 50 and the display panel 60 for limiting or calibrating the position of the fingerprint sensing module 50 and for supporting the display panel 60 . The middle frame 100 has an opposite first surface S1 , a second surface S2 and a light entrance P, wherein the first surface S1 faces the display panel 60 and the second surface S2 faces the fingerprint sensing module 50 . Therefore, the sensing light beam L2 is transmitted toward the side of the display panel 60 through the light entrance P of the middle frame 100 , and then transmitted to the fingerprint sensing module 50 . In this embodiment, the optical module 56 is located in the light entrance P, but the present invention is not limited thereto.

In this embodiment, the first surface S1 of the middle frame 100 includes an annular groove G recessed toward the second surface S2 , and the annular groove G and the light entrance P have a distance D. Most of the first surface S1 and the second surface S2 are flat horizontal surfaces, and a small part has other structures, such as the annular groove G mentioned above. Since the annular groove G has a distance D from the light entrance P, when the stray light L3 is transmitted to the annular groove G, it will not be easily reflected to the fingerprint sensing module 50 . In different embodiments, slopes with different slopes can be designed at the distance D to reduce the probability of the stray light L3 being reflected into the fingerprint sensing module 50 . Therefore, when the stray light L3 is transmitted toward the middle frame 100 , the stray light L3 will not be directly or indirectly reflected and transmitted to the fingerprint sensing module 50 due to being transmitted to the surface of the middle frame 100 . In this way, the middle frame 100 designed in this embodiment can avoid reflecting the stray light L3 to the fingerprint sensing module 50 , thereby preventing the fingerprint sensing module 50 from sensing noise light signals and effectively improving the fingerprint sensing effect. In some embodiments, the electronic device 10 may further include a black annular member disposed in the annular groove G to absorb the stray light L3 and increase the support when the finger 20 is pressed, but the invention is not limited thereto.

In detail, the first surface S1 of the middle frame 100 has a first annular inclined surface S11 located between the annular groove G and the light entrance P. In this embodiment, the first annular inclined surface S11 and the horizontal reference plane have a first included angle B1, and the first included angle B1 is greater than 30 degrees. In this way, the stray light L3 near the center (ie, the light transmitted between the annular groove G and the light entrance P) can be reflected away from the light entrance P by the first annular slope S11, thereby avoiding the Reflected from the middle frame 100 and transmitted to the fingerprint sensing module 50 .

In this embodiment, the first surface S1 of the middle frame 100 further has a second annular inclined surface S12 located between the annular groove G and the first annular inclined surface S11. In other words, a part of the annular groove G is formed by the second annular inclined surface S12. In this embodiment, the second annular inclined surface S12 has a second included angle B2 with the horizontal reference plane, and the second included angle B2 is greater than or equal to 10 degrees. In this embodiment, the second annular inclined surface S12 is directly adjacent to the first annular inclined surface S11, but the present invention is not limited thereto. In this way, the sensing beam L2 transmitted into the annular groove G can pass through the second annular inclined surface S12 And it is transmitted in the direction away from the light entrance P, so as to prevent the stray light L3 from being reflected into the fingerprint sensing module 50 by the structural surface of the middle frame 100, so as to prevent the fingerprint sensing module 50 from sensing the noise light signal .

To sum up, in the electronic device of the present invention, through the annular groove design, the middle frame can reduce the reflection of stray light to the fingerprint sensing module, so as to prevent the fingerprint sensing module from sensing the stray light signal. Effectively improve the fingerprint sensing effect.

Although the present invention has been disclosed as above with examples, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. The protection scope of the present invention shall be determined by the scope of the appended patent application.

10: Electronics 20: Fingers 50: Fingerprint sensor module 52: circuit board 54: Photosensitive element 56: Optical module 60: Display panel 100: Middle frame G: Annular groove L1: Lighting beam L2: Sensing beam P: light entrance

Claims (8)

An electronic device, comprising: a fingerprint sensing module adapted to sense a sensing beam reflected by a finger; a display panel, disposed on the fingerprint sensing module, adapted to provide an illumination beam to the finger to reflect the sensing beam; and a middle frame, disposed between the fingerprint sensing module and the display panel, the middle frame has a first face, a second face and a light entrance that are opposite to each other, the first face The face faces the display panel, the second face faces the fingerprint sensing module, and the sensing beam passes through the light entrance to be transmitted to the fingerprint sensing module, wherein the first face It includes an annular groove concave toward the second surface, the annular groove has a distance from the light entrance, the first surface has a first annular inclined surface and a second annular inclined surface, the first annular inclined surface The annular inclined surface is located between the annular groove and the light entrance, and the second annular inclined surface is located between the annular groove and the first annular inclined surface. The electronic device of claim 1, wherein a first included angle is formed between the first annular inclined surface and the horizontal reference plane, and the angle of the first included angle is greater than 30 degrees. The electronic device of claim 1, wherein a second included angle exists between the second annular inclined surface and the horizontal reference plane, and the angle of the second included angle is greater than or equal to 10 degrees. The electronic device of claim 1, wherein the second annular slope is directly adjacent to the first annular slope. The electronic device of claim 1, wherein a part of the annular groove is formed by the second annular inclined surface. The electronic device according to claim 1, wherein the fingerprint sensing module comprises a circuit board, a photosensitive element and an optical module. The electronic device of claim 6, wherein the optical module is located in the light entrance. The electronic device according to claim 1, further comprising: a black annular member disposed in the annular groove.

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