CN211554956U - Fingerprint sensing module and electronic device - Google Patents

Abstract

The utility model provides a fingerprint sensing module, comprising an image sensor, a collimator, a filter and a light shielding structure. The collimator is arranged on the image sensor, and the filter is arranged between the image sensor and the collimator. The light shielding structure is arranged around the filter to block stray light from entering the image sensor. An electronic device is also proposed.

Description

Fingerprint Sensing Module and Electronic Device

technical field

The utility model relates to a sensing module, in particular to a fingerprint sensing module and an electronic device.

Background technique

With the development of portable electronic devices (such as smart phones or tablet computers) toward a large screen-to-body ratio or a full-screen display, the traditional capacitive fingerprint sensing module located beside the screen can no longer be disposed on the front of the electronic device. Therefore, the solution of the capacitive fingerprint sensing module disposed on the side or the back of the electronic device is adopted. However, the capacitive fingerprint sensing module placed on the side or the back has its inconvenience in use, so an optical fingerprint sensing module placed under the screen has been developed recently.

Since the fingerprint sensing module is placed under the screen, the thinner the fingerprint sensing module is, the better to avoid affecting the thickness of the electronic device. On the other hand, when an optical fingerprint sensing scheme is used to illuminate the fingerprint with the visible light emitted by the screen, and use the image sensor below the screen to sense the visible light reflected by the fingerprint, in order to avoid sunlight from affecting the accuracy of fingerprint identification, the optical method is generally used. An infrared cut-off filter is added above the fingerprint sensing module to solve the problem of use under strong outdoor light. However, such a design makes it difficult to reduce the thickness of the fingerprint sensing module, which in turn leads to an excessively thick electronic device.

Another solution is to integrate the infrared cut filter directly on the fingerprint sensor chip and place it between the image sensor and the collimator, which can reduce the thickness of the glass substrate required for the external infrared cut filter. This in turn reduces the overall module thickness. However, since the area of the IR cut filter integrated on the chip does not exceed the area of the image sensor, this design allows stray light (such as infrared or visible light) to enter the image sensor from the edge of the image sensor, thereby causing noise.

Utility model content

The utility model is directed to a fingerprint sensing module and an electronic device, which has good sensing effect and can have a relatively thin thickness.

An embodiment of the present invention provides a fingerprint sensing module, which includes an image sensor, a collimator, a filter and a light-shielding structure. The collimator is arranged on the image sensor, and the filter is arranged between the image sensor and the collimator. The light-shielding structure is disposed around the filter to block stray light from entering the image sensor.

An embodiment of the present invention provides an electronic device including a display panel and the above-mentioned fingerprint sensing module. The fingerprint sensing module is disposed under the display panel for sensing light emitted by the display panel, reflected by a finger placed on the display panel, and transmitted through the display panel.

In an embodiment of the present invention, the filter is an infrared light cut-off filter.

In an embodiment of the present invention, the light-shielding structure is a light-shielding glue, which covers the side surfaces of the image sensor, the filter and the collimator.

In an embodiment of the present invention, the light-shielding structure is a light-shielding tape attached to the edge of the upper surface of the collimator.

In an embodiment of the present invention, the fingerprint sensing module further includes a flexible printed circuit board, which is disposed on the bottom plate and is located around the image sensor.

In an embodiment of the present invention, the light-shielding structure is a light-shielding glue, which covers the side surfaces of the image sensor, the filter, and the collimator, and is filled in the image sensor, the filter, and the collimator. in the gap between the entirety of the light sheet and the collimator and the entirety of the flexible printed circuit board and the foam thereon.

In an embodiment of the present invention, the light-shielding structure is a light-shielding tape, which is attached to the edge of the upper surface of the collimator and covers the image sensor, the filter and the collimator The gap between the whole of the device and the whole of the flexible printed circuit board and the foam thereon.

In an embodiment of the present invention, the collimator is a fiber plate, a lens array or a lens.

In the fingerprint sensing module and the electronic device of the embodiment of the present invention, the filter is arranged between the image sensor and the collimator, and the light-shielding structure is arranged around the filter to block stray light from entering the image sensor . Therefore, the fingerprint sensing module and the electronic device can have a good fingerprint sensing effect and can have a thinner thickness.

Description of drawings

The accompanying drawings are included to provide a further understanding of the present invention, and are incorporated into and constitute a part of this specification. The drawings illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention.

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

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

Explanation of reference numerals

50: Fingers

100, 100a: Electronic devices

110: Display panel

112: Light

120: Foam

200, 200a: Fingerprint sensing module

210: Bottom Plate

220: Image Sensor

230: Collimator

232: Upper surface

240: Filter

250, 250a: Shading structure

260: Flexible Printed Circuit Board

270: Bonding Wire

280: Die Attach Film

G: Gap

Detailed ways

Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals are used in the drawings and description to refer to the same or similar parts.

FIG. 1 is a schematic cross-sectional view of an electronic device according to an embodiment of the present invention. Referring to FIG. 1 , the electronic device 100 of this embodiment includes a display panel 110 and a fingerprint sensing module 200 . The display panel 110 is, for example, an organic light-emitting diode (organic light-emitting device, OLED) display panel. However, in other embodiments, the display panel 110 may also be a liquid crystal display panel or other suitable display panels. The fingerprint sensing module 200 is disposed under the display panel 110 to sense the light 112 emitted by the display panel 110 , reflected by the finger 50 placed on the display panel 110 and transmitted through the display panel 110 . In this embodiment, the display panel 110 is, for example, a transparent display panel. However, in other embodiments, the display panel 110 may also be a display panel with a light-transmitting opening in the area above the fingerprint sensing module 200 . The electronic device 100 is, for example, a mobile phone, a tablet computer, a notebook computer or other suitable electronic devices.

The fingerprint sensing module 200 includes a base plate 210 , an image sensor 220 , a collimator 230 , a filter 240 and a light shielding structure 250 . The image sensor 220 is disposed on the base plate 210 , the collimator 230 is disposed on the image sensor 220 , and the filter 240 is disposed between the image sensor 220 and the collimator 230 . In this embodiment, the bottom plate 210 is a rigid metal sheet, such as an iron sheet. The image sensor 220 is, for example, a complementary metal oxide semiconductor (CMOS) sensor or a charge coupled device (CCD). The collimator 230 is, for example, a collimation structure formed by a fiber plate, a microlens array or other methods, which can allow the light 112 from the finger 50 to be collimated and transmitted to be imaged on the image sensor 220. Alternatively, the collimator 230 can also be any other device capable of collimating and passing the light 112 from the finger 50 to be imaged on the image sensor 220 . The filter 240 is, for example, an infrared light cut filter. However, in other embodiments, the filter 240 may also be a filter for filtering other visible light wavelength bands or invisible light wavelength bands.

The light shielding structure 250 is disposed around the filter 240 and the image sensor 220 to block stray light from entering the image sensor 220 . In this embodiment, the light-shielding structure 250 is a light-shielding glue, such as a light-absorbing glue (eg, black glue). In this embodiment, the fingerprint sensing module 200 further includes a flexible printed circuit (FPC) 260 disposed on the bottom plate 210 and located around the image sensor 220 . The image sensor 220 is electrically connected to the flexible printed circuit board 260 through bonding wires 270 . In one embodiment, the light shielding structure 250 is filled in the gap G between the image sensor 220 and the flexible printed circuit board 260 to cover the side surfaces of the image sensor 220 , the filter 240 and the collimator 230 to block stray light. Enter from the side of the image sensor 220 . In one embodiment, the light shielding structure 250 is filled in the gap G between the entirety of the image sensor 220 , the filter 240 and the collimator 230 and the flexible printed circuit board 260 and the entirety of the foam 120 thereon . In addition, in one embodiment, the light shielding structure 250 may cover the bonding wire 270 .

In the fingerprint sensing module 200 and the electronic device 100 of the present embodiment, the filter 240 is disposed between the image sensor 220 and the collimator 230 , so the filter 240 can be directly formed on the image sensor 220 , so that the fingerprint can be sensed. The measuring module 200 can have a thinner thickness, thereby reducing the thickness of the electronic device 100 . In addition, in this embodiment, since the stray light is blocked by the light shielding structure 250 and cannot enter the image sensor 220 , the fingerprint sensing module 200 and the electronic device 100 installed with the fingerprint sensing module 200 can obtain a high-quality image fingerprint images without overexposing the edges of the fingerprint image due to stray light.

In this embodiment, the image sensor 220 can be attached to the base plate 210 through a die attach film 280 . In addition, the electronic device 100 may have the foam 120 disposed between the flexible printed circuit board 260 and the display panel 110 .

2 is a schematic cross-sectional view of an electronic device according to another embodiment of the present invention. Referring to FIG. 2 , the electronic device 100 a of this embodiment is similar to the electronic device 100 of FIG. 1 , and the main differences between the two are as follows. In the fingerprint sensing module 200a of the electronic device 100a of the present embodiment, the light-shielding structure 250a is a light-shielding tape, such as a light-absorbing tape (eg, black tape), which is attached to the edge of the upper surface 232 of the collimator 230, and The gap G between the image sensor 220 and the flexible printed circuit board 260 or the foam 120 is covered. In one embodiment, the light shielding structure 250a covers the gap G between the entirety of the image sensor 220 , the filter 240 and the collimator 230 and the entirety of the flexible printed circuit board 260 and the entire foam 120 thereon.

The materials used in the light-shielding structures 250 and 250a of the above-mentioned embodiments may be materials capable of shielding visible light, infrared light and ultraviolet light, or materials capable of absorbing visible light, infrared light and ultraviolet light. In addition, the light-shielding structures 250 and 250a of the above-mentioned embodiment can be in the shape of a rectangular frame, and the opening in the middle of the rectangular frame exposes the sensing area (ie, the area used for light sensing) of the image sensor 220, but the present invention is not limited to this. .

To sum up, in the fingerprint sensing module and the electronic device of the embodiments of the present invention, the filter is arranged between the image sensor and the collimator, and the light-shielding structure is arranged around the filter to block impurities Astigmatism enters the image sensor. Therefore, the fingerprint sensing module and the electronic device can have a good fingerprint sensing effect, and thus can have a thinner thickness.

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

Claims (16)

1. a fingerprint sensing module, is characterized in that, comprises: Image Sensor; a collimator, configured on the image sensor; a filter, disposed between the image sensor and the collimator; and The light-shielding structure is arranged around the filter to block stray light from entering the image sensor. 2. The fingerprint sensing module of claim 1, wherein the filter is an infrared light cut filter. 3 . The fingerprint sensing module of claim 1 , wherein the light-shielding structure is a light-shielding glue, which covers the side surfaces of the image sensor, the filter and the collimator. 4 . 4 . The fingerprint sensing module of claim 1 , wherein the light shielding structure is a light shielding tape attached to the edge of the upper surface of the collimator. 5 . 5 . The fingerprint sensing module according to claim 1 , further comprising a flexible printed circuit board disposed on the bottom plate and located around the image sensor. 6 . 6 . The fingerprint sensing module according to claim 5 , wherein the light-shielding structure is a light-shielding glue, which covers the side surfaces of the image sensor, the filter and the collimator, and is filled in the image. 7 . in the gap between the whole of the sensor, the filter and the collimator and the whole of the flexible printed circuit board and the foam thereon. 7 . The fingerprint sensing module according to claim 5 , wherein the light-shielding structure is a light-shielding tape, which is attached to the edge of the upper surface of the collimator and covers the image sensor and the filter. 8 . and the gap between the whole of the collimator and the whole of the flexible printed circuit board and the foam thereon. 8. The fingerprint sensing module of claim 1, wherein the collimator is a fiber plate, a lens array, or a lens. 9. An electronic device, characterized in that, comprising: display panel; and A fingerprint sensing module, disposed under the display panel, is used for sensing light emitted by the display panel, reflected by a finger placed on the display panel and penetrating the display panel, the fingerprint sensing Modules include: Image Sensor; a collimator, configured on the image sensor; a filter, disposed between the image sensor and the collimator; and The light-shielding structure is arranged around the filter to block stray light from entering the image sensor. 10. The electronic device of claim 9, wherein the filter is an infrared light cut filter. 11 . The electronic device according to claim 9 , wherein the light-shielding structure is a light-shielding glue, covering side surfaces of the image sensor, the filter and the collimator. 12 . 12 . The electronic device of claim 9 , wherein the light shielding structure is a light shielding tape attached to an edge of the upper surface of the collimator. 13 . 13. The electronic device of claim 9, wherein the fingerprint sensing module further comprises a flexible printed circuit board disposed on the bottom plate and located around the image sensor. 14. The electronic device according to claim 13, wherein the light-shielding structure is a light-shielding glue, which covers the image sensor, the filter and the side surfaces of the collimator, and is filled in the image sensor, the filter and the collimator. in the gap between the entirety of the filter and the collimator and the entirety of the flexible printed circuit board and the foam thereon. 15. The electronic device according to claim 13, wherein the light-shielding structure is a light-shielding tape, which is attached to the edge of the upper surface of the collimator and covers the image sensor, the filter and the The gap between the whole of the collimator and the whole of the flexible printed circuit board and the foam thereon. 16. The electronic device of claim 9, wherein the collimator is a fiber optic plate, a lens array, or a lens.

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