CN212031869U - Optical fingerprint identification module and electronic equipment - Google Patents

Abstract

The utility model provides an optics fingerprint identification module and electronic equipment, the module includes: an optical structure portion including a microlens unit, an aperture stop layer, and a first light splitting unit; the micro lens unit comprises a micro lens array formed by a plurality of micro lenses, the first light splitting unit comprises a first light shielding body and a first light transmitting part arranged on the first light shielding body, the first light splitting unit is positioned near a focal plane of the micro lens unit, and the first light transmitting parts correspond to the micro lenses in the micro lens array one by one; the aperture diaphragm layer is provided with a plurality of light transmission holes and is arranged between the micro lens and the first light splitting unit; the light detection array is arranged below the optical structure part and comprises a photosensitive pixel array used for receiving an optical signal carrying fingerprint information and transmitted by the optical structure part; the utility model provides an optics fingerprint identification module and electronic equipment, its thickness is less, can satisfy the requirement of optics fingerprint module slimming.

Description

Optical fingerprint identification module and electronic equipment

Technical Field

The utility model relates to a fingerprint identification technical field especially relates to an optics fingerprint identification module and electronic equipment.

Background

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

At present, the optical fingerprint recognition module generally includes a micro lens, an optical filter and a photosensitive unit, which are sequentially arranged from top to bottom. Further, the micro lens is fixed on the lens bracket. The micro lens is used for receiving the reflected light on the fingerprint of the organism so as to identify the fingerprint of the organism. The optical fingerprint identification module adopting the micro lens in the prior art has strict requirements on object distance and image distance, and has amplification and reduction in a certain proportion, and because the requirements on optical upper optical path lead to the fact that the optical fingerprint identification module in the prior art has larger volume and thicker thickness, the requirement on thinning of the optical fingerprint module is difficult to meet.

It should be noted that the above background description is only for the sake of clarity and complete description of the technical solutions of the present invention, and is set forth for facilitating understanding of those skilled in the art. These solutions are not considered to be known to the person skilled in the art merely because they have been set forth in the background section of the present invention.

SUMMERY OF THE UTILITY MODEL

Based on aforementioned prior art defect, the utility model provides an optics fingerprint identification module and electronic equipment, its thickness is less, can satisfy the requirement of optics fingerprint module slimming.

In order to achieve the above object, the present invention provides the following technical solutions. An optical fingerprint identification module, it includes: an optical structure portion including a microlens unit, an aperture stop layer, and a first light splitting unit; the micro lens unit comprises a micro lens array formed by a plurality of micro lenses, the first light splitting unit comprises a first light shielding body and a first light transmitting part arranged on the first light shielding body, the first light splitting unit is positioned near a focal plane of the micro lens unit, and the first light transmitting part corresponds to the micro lenses in the micro lens array one by one; the aperture diaphragm layer is provided with a plurality of light transmission holes and is arranged between the micro lens and the first light splitting unit; and the light detection array is arranged below the optical structure part and comprises a photosensitive pixel array which is used for receiving the light signal carrying the fingerprint information and transmitted by the optical structure part.

In a preferred embodiment, the aperture stop layer is disposed adjacent to the microlens unit and below the microlens unit.

As a preferred embodiment, the method further comprises: and the first medium layer is arranged between the aperture diaphragm layer and the first light splitting unit.

In a preferred embodiment, the first medium layer is filled in an opening formed in the first light transmitting portion of the first light splitting unit.

As a preferred embodiment, the method further comprises: and a second medium layer with preset thickness is arranged between the aperture diaphragm layer and the micro-lens layer.

As a preferred embodiment, the method further comprises: a filter layer disposed between the microlens unit and the photosensitive pixel array.

In a preferred embodiment, the filter layer is formed on a surface of the first light splitting unit facing the microlens.

In a preferred embodiment, the filter layer is plated on the surface of the light detection array.

In a preferred embodiment, the optical structure is partially integrated on a photosensitive area integrally disposed on the photosensitive pixel array.

As a preferred embodiment, the optical structure portion is attached to the array of photosensitive pixels by an optical adhesive.

As a preferred embodiment, the method further comprises: a second light splitting unit disposed below the optical structure portion; the second light splitting unit comprises a second light shielding body and a plurality of second light transmitting parts arranged on the second light shielding body.

In a preferred embodiment, the second light splitting unit is formed in the light detection array and located above the photosensitive pixel array.

In a preferred embodiment, the second light splitting unit is disposed on any one of a plurality of metal layers of a photosensitive area of the photosensitive pixel array.

In a preferred embodiment, the second spectroscopic unit is provided outside the photodetector array.

In a preferred embodiment, the second spectroscopic unit is made of a metal material and is formed above the photodetector array.

In a preferred embodiment, the second light splitting unit and the optical structure portion are integrated outside a photosensitive area integrally adhered to the photosensitive pixel array.

As a preferred embodiment, the method further comprises: and the third medium layer is arranged between the second light splitting unit and the light detection array and is filled in the opening formed by the second light transmission part.

In a preferred embodiment, the second light transmission portions correspond to the first light transmission portions one by one, or one second light transmission portion corresponds to a plurality of first light transmission portions.

In a preferred embodiment, the light detection array is a light detection array chip manufactured by a silicon-based semiconductor process.

An electronic device is provided with the optical fingerprint identification module.

The optical fingerprint identification module and the electronic equipment provided by the embodiment of the utility model have the advantages that through the arrangement of the optical structure part and the light detection array, the thinned optical structure part realizes the collection of optical signals carrying fingerprint information; and the light detection array can receive the light signal carrying the fingerprint information transmitted by the optical structure part so as to form a fingerprint image on the object to be detected. Since the thickness of the microlens unit is in the order of μm (micrometer); the whole thickness of the optical fingerprint identification module can be reduced by using the optical structure part to replace the optical structure part of the micro lens. Therefore, the utility model provides an optics fingerprint identification module and electronic equipment can satisfy the requirement of the slimming of optics fingerprint module under the prerequisite that can reach the basic performance of optics fingerprint identification module.

Specific embodiments of the present invention are disclosed in detail with reference to the following description and accompanying drawings, which specify the manner in which the principles of the invention may be employed. It should be understood that the embodiments of the present invention are not so limited in scope. The embodiments of the invention include many variations, modifications and equivalents within the spirit and scope of the appended claims.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments, in combination with or instead of the features of the other embodiments.

It should be emphasized that the term "comprises/comprising" when used herein, is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps or components.

Drawings

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. In addition, the shapes, the proportional sizes, and the like of the respective members in the drawings are merely schematic for helping the understanding of the present invention, and do not specifically limit the shapes, the proportional sizes, and the like of the respective members of the present invention. The skilled person in the art can, under the teaching of the present invention, choose various possible shapes and proportional dimensions to implement the invention according to the specific situation. In the drawings:

fig. 1 is a schematic structural diagram of an optical fingerprint identification module according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of an optical path of a plurality of microlenses according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of an optical path of a microlens according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a light detection array according to an embodiment of the present invention.

Description of reference numerals:

5. a light detection array; 6. an insulating dielectric layer; 7. a passivation layer; 11. a microlens unit; 13. an aperture stop layer; 15. a first light-shielding body; 17. a first light-transmitting portion; 19. a first light splitting unit; 23. a second light splitting unit; 25. a second light-shielding body; 27. a second light-transmitting portion; 41. a microlens; 43. a light-transmitting hole; 47. a filter layer; 311. a light-sensitive region; 303. a photoelectric conversion device; 312a, a first metal layer; 312b, a second metal layer; 312c, a third metal layer; 51. a first dielectric layer; 53. a second dielectric layer.

Detailed Description

In order to make the technical solutions in the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall fall within the protection scope of the present invention.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a single embodiment.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In this specification, a component of an embodiment of the present invention is defined as "up" in a direction toward or facing a user and "down" in a direction away from the user in a normal use state.

Specifically, when the collimating structure of the embodiment of the present invention is configured in a display device, the direction in which the display screen of the display device points or faces the user is defined as "up", and the opposite direction, or the direction away from the user is defined as "down".

More specifically, an upward direction illustrated in fig. 1 to 4 is defined as "up", and a downward direction illustrated in fig. 1 to 4 is defined as "down".

It should be noted that the definitions of the directions in the present specification are only for convenience of describing the technical solution of the present invention, and do not limit the directions of the alignment structure of the embodiments of the present invention in other scenarios, including but not limited to use, test, transportation, and manufacture, which may cause the orientation of the component to be reversed or the position of the component to be changed.

The embodiment of the utility model provides an optics fingerprint identification module, its thickness is less, can satisfy the requirement of optics fingerprint module slimming. Specifically, the optical fingerprint identification module generally comprises an optical mechanism portion and a light detection array 5. The optical mechanism portion includes a microlens unit 11, an aperture stop layer 13, and a first light splitting unit 19.

In the present embodiment, the microlens unit 11 includes a microlens 41 array formed of several microlenses 41. For example, as shown in fig. 2, the number of the microlenses 41 is 3. 3 microlenses 41 are arranged in the horizontal direction to form an array of microlenses 41. More specifically, the optical axis of each microlens 41 extends in the up-down direction, and the plurality of microlenses 41 are arranged side by side in the horizontal direction. That is, the light passing through the microlens unit 11 can be converged.

Further, the first light splitting unit 19 is located near a focal plane formed by the focal points of the respective microlenses 41 in the microlens unit 11. The aperture stop layer 13 is disposed between the microlens 41 and the first light splitting unit 19. For example, as shown in fig. 2, the microlens unit 11 is located above the first light splitting unit 19. Light rays within a predetermined angle range above the microlens unit 11 can be condensed near the first light splitting unit 19.

In the present embodiment, the first light splitting unit 19 includes the first light-shielding body 15 and the first light-transmitting portions 17 provided on the first light-shielding body 15 in one-to-one correspondence with the microlenses 41 in the microlens unit 11. For example, as illustrated in fig. 2, the first light transmitting portion 17 is located at the center of the projection of the microlens 41 on the first light splitting unit 19, and is used for collecting the optical signal in the angular range directly above the microlens 41. In other embodiments, if the microlens 41 is used to collect light in a non-directly-above angle range, the position of the first light-transmitting portion 17 is not located at the center of the projection of the microlens 41 on the first light splitting unit 19, and will not be illustrated and described in detail herein.

The optical structure shown in fig. 2 mainly performs a collimation function, i.e. collects optical signals in an angle range directly above the microlens 41, and optical signals in other angle ranges can be blocked or absorbed by the first light-shielding body 15 in the first light splitting unit 19. Only the light signal in the angular range directly above the microlens 10 is focused by the microlens 41 and can reach the light detection array 5 below the optical structure portion through the first light transmitting portion 17 in the first light splitting unit 19.

In one embodiment, the first light-transmitting portion 17 is an opening. Specifically, the first light-shielding body 15 is provided with an opening at the center thereof through which it passes. For example, when the optical structure portion is formed by a film structure, the opening may be an opening penetrating the first light splitting unit 19. Of course, the first light transmission portion 17 is not limited to the opening, and may have another structure. For example, the first light splitting unit 19 may be manufactured by a semiconductor process, and when a transparent medium needs to be manufactured above the first light splitting unit 19, the transparent medium may be filled into the first light transmitting portion 17 in the first light splitting unit 19. For example, the transparent material is silicon dioxide or other transparent dielectric layer materials commonly used in semiconductor processes. The transparent dielectric layer does not affect the optical path of the optical structure.

Further, the first light-shielding body 15 may be black. The black first light-shielding body 15 can absorb light of various colors irradiated thereon, thus achieving the purpose of shielding light. Of course, the first light splitting unit 19 may be formed of black photoresist. Of course, the first light splitting unit 19 is not limited to be formed using photoresist. Other materials, such as metals, etc., are also possible and are not specified in this application.

Further, the first light splitting unit 19 is located near the focal plane of the microlens unit 11. Specifically, for example, the focal point of the microlens 41 is located in the corresponding first light transmission portion 17, and is located near, at an upper or lower position than the first light transmission portion 17. When the optical signal of the microlens 41 in the directly-above angular range is condensed on the focal point, the condensed optical signal can enter the first light-transmitting portion 17. However, optical signals in other angular ranges above the other microlenses 41 tend to converge on the first light shielding member 15, and thus are not easy to enter the first light transmitting portion 17, and are shielded by the first light shielding member 15, i.e., are reflected or absorbed by the first light shielding member 15, and cannot pass through the first light splitting unit 19 and enter the lower portion of the optical structure portion. Therefore, the first light splitting unit 19 can perform preliminary screening on the optical signal at the angle focused by the microlens 41, as shown in fig. 2 and 3, focus the optical signal at the angle directly above the microlens, and preliminarily filter out the signal light at other angles, so as to achieve collimation.

In the present embodiment, the first light transmitting portions 17 correspond one-to-one to the microlenses 41 in the microlens 41 array. For example, as shown in fig. 2, each of the first light-transmitting portion 17 and the microlenses 41 in the microlens 41 array is 3. And each of the first light-transmitting portions 17 is located directly below a microlens 41 in the corresponding microlens 41 array. The focal point of each microlens 41 is located within the corresponding first light-transmitting portion 17.

Preferably, the distance between adjacent microlenses 41 is 12.5 μm. Of course, the distance between adjacent microlenses 41 is not limited to 12.5 μm, but may be other distances, such as 13 μm, and is not limited in this application. Since the thickness of the microlens 41 is of the order of μm (micrometer), the thickness of the microlens unit 11 is of the order of μm (micrometer). The thickness of the microlens unit 11 is thus small.

Further, when the ratio between the thickness and the aperture of the microlens 41 is larger, the curvature of the microlens 41 is smaller, and thus the converging effect of the microlens 41 is better; but at the same time the larger the thickness of the micro-lenses 41, and the larger the thickness of the micro-lenses 41, the smaller or thinner volume requirements cannot be met. In order to balance the thickness requirement and the converging effect requirement of the micro-lenses 41, the ratio between the thickness and the aperture of the micro-lenses 41 is 20% to 50%. Specifically, the ratio between the thickness and the aperture of the microlens unit 41 is 20%. Or the ratio between the thickness and the aperture of the microlens 41 is 50%. Or the ratio between the thickness and the aperture of the microlens 41 is more than 20% and less than 50%. The aperture may refer to a diameter of a maximum circumscribed circle of a top view in the microlens 41 as shown in fig. 1. For example, when the top view of the microlens 41 shown in fig. 1 is a hexagon, the aperture is the diameter of a circumscribed circle of the hexagon. When the microlens 41 shown in fig. 1 has a circular shape in plan view, the aperture is the diameter of the circular shape.

In the present embodiment, the aperture layer 13 is provided with a plurality of light-transmitting holes 43. The aperture stop layer 13 is disposed between the microlens unit 11 and the first light splitting unit 19. As shown in fig. 2, for example, the aperture stop layer 13 is located below the microlens unit and above the first light splitting unit 19. The aperture stop layer 13 is provided mainly to block interference of optical signals between the microlenses 41 and the microlenses 41 in the microlens unit 11. For example, the signal light in the range not directly above the barrier microlens 41 may be condensed on the aperture stop layer 13 of the microlens 41 by the condensation of the barrier microlens 41. The aperture stop layer 13 may be disposed adjacent to the microlens 41 as shown in fig. 2, or may be disposed at a predetermined distance from the microlens unit 11 as illustrated in fig. 1. The closer the aperture stop layer 13 is to the microlens unit 11, the greater the influence of the light flux on the microlenses 41, and specifically, the closer the aperture stop layer 13 is to the microlens unit 11, the smaller the light flux that passes through the aperture in the aperture stop layer 13. Therefore, it is possible to set a specific position of the aperture stop layer 13 while balancing the crosstalk between the light flux and the optical signal between the microlenses 41. Of course the size of the aperture opening in the aperture layer 13 also affects the light flux. The aperture in the aperture stop layer may be open or filled with a transparent dielectric material, depending on the specific process.

The material of the light shielding part in the aperture stop layer 13 may be black, and the black light shielding part can absorb the light signal irradiated thereon, so as to perform the blocking and selecting of the light signal, remove the interference signal light, and further improve the image quality output by the light detection array.

In some embodiments, the aperture stop layer 13 may be formed of photoresist. Of course, the aperture stop layer 13 is not limited to be formed by photoresist, and may be formed by other materials, such as metal, according to different manufacturing processes.

The light transmission holes 43 of the aperture stop layer correspond to the microlenses 41 in the microlens 41 array one by one. For example, as shown in fig. 2, each of the light-transmitting holes 43 and the microlenses 41 in the microlens 41 array is 3. And each light-transmissive hole 43 is located directly below a microlens 41 in the corresponding array of microlenses 41.

Further, the aperture of the light-transmitting hole 43 is smaller than the aperture of the microlens unit 11. The light-transmitting holes 43 thus limit the converged emergent light so that part of the emergent light can pass through the light-transmitting holes 43 and part of the emergent light cannot pass through the light-transmitting holes 43, thereby enabling the screening and rejection of non-target optical signals, such as non-target optical signals focused adjacent to the microlenses 41. The aperture stop layer 13 can filter the non-target signals of the mutual crosstalk between the microlenses 41, and help to improve the quality of the fingerprint image output by the light detection array 5. In this embodiment, the diameter of the aperture in the aperture stop layer 13 is generally set smaller than the aperture of the microlens 11. Specifically, for example, when the aperture of the microlens unit 11 is 12 μm, the aperture of the light transmission hole 43 is smaller than 12 μm.

Further, the aperture stop layer 13 has a larger opening area of the light transmission hole 43 as it is closer to the microlens unit 11. The area of the light-transmitting hole 43 in this embodiment is larger than the area of the light-transmitting hole 43 of the aperture stop layer 13 in the embodiment illustrated in fig. 1. The aperture stop layer 13 functions as a stop, and therefore has an opening area larger than the area of the corresponding first light-transmitting portion 17 in the optical path of the same microlens 41.

In some embodiments, as shown in FIG. 2, the aperture stop layer 13 is disposed proximate to the microlens element 11. And an aperture stop layer 13 is located below the microlens unit 11. Specifically, the microlens unit 11 may be formed after filling a material highly transmissive to light in the light-transmissive hole 43 of the aperture stop layer 13. The light-transmitting holes 43 may be formed by a suitable method according to the material of the aperture stop layer 13, for example, if the aperture stop layer 13 is made of black glue, the light-transmitting holes 43 may be formed by using a suitable mold. The aperture stop layer 13 is made of corresponding materials according to the size of the light hole 43 and the light hole 43 is made in a corresponding mode.

In other embodiments, the aperture stop layer 13 is spaced apart from the microlens unit 11, and a dielectric layer with a predetermined thickness, which is the second dielectric layer 53 described below, may be added between the aperture stop layer and the microlens unit. As shown in fig. 1, the second dielectric layer 53 needs to be made of a light-transmitting material to avoid affecting the light flux from the microlens unit 11 to the aperture stop layer 13. Further, a first medium layer 51 may be further provided between the aperture stop layer 13 and the first light splitting unit 19. Specifically, the first dielectric layer 51 may be formed after filling a highly light-transmissive material in an opening formed in the first light-transmissive portion 17 of the first light splitting unit 19.

Further, in the embodiment illustrated in fig. 2, that is, in the embodiment in which the aperture stop layer 13 is disposed adjacent to the microlens unit 11, the aperture of the light transmission hole 43 is less than 80% of the aperture of the microlens unit 11. That is, the maximum value of the aperture of the light transmission hole 43 is 80% of the aperture of the microlens unit 11. Specifically, for example, when the aperture of the microlens unit 11 is 12 μm, the aperture of the light transmission hole 43 is smaller than 12 μm × 80% ═ 10 μm. In the embodiment illustrated in fig. 1, i.e., the embodiment in which the aperture stop layer 13 is spaced apart from the microlens unit 11, the aperture of the light-transmitting hole 43 is larger than the aperture of the first light-transmitting portion 17 in the first light-splitting unit 19.

In the present embodiment, the light detection array 5 is disposed below the optical structure portion. The light sensing array 5 comprises an array of light sensitive pixels. The photosensitive pixel array is used for receiving the target signal light transmitted by the optical structure part. The light detection array 5 is used for collecting fingerprint images and/or outputting images of target light signals transmitted after being processed by the optical structure part.

In the present embodiment, as shown in fig. 4, the photo detector array 5 includes a photosensitive pixel array fabricated on a wafer or a silicon substrate by a semiconductor process, a photosensitive region 311 is disposed at a position corresponding to the photosensitive pixel array, and the photosensitive region 311 is formed on the silicon substrate. The photoelectric conversion device 303 is formed at the lowermost part of the photosensitive region 311, and a plurality of metal layers (312a, 312b, 312c) are formed above the photoelectric conversion device 303 and are isolated by insulating medium layers. To avoid metal layers (312a, 312b, 312c) interfering with the optical path of the optical signal carrying the fingerprint information passing through the microlens unit 11 to the photoelectric conversion device 303, several metal layers (312a, 312b, 312c) are routed to the array of microlenses 41 at locations outside the optical path 303 of the focused optical signal to the photoelectric conversion device 303.

The metal layers may be electrically connected to each other through a via 304, the bottom metal layer may be connected to the photoelectric conversion device 303 through a contact 305, and the contact 305 may be formed in the insulating dielectric layer 6. A passivation layer 7 may be formed on the top metal layer 312a, and the passivation layer 7 protects the metal layers in the light detecting array 5 from contamination and damage. The passivation layer 7 is a light-transmitting layer made of a transparent material. For example, the passivation layer 7 may be a silicon oxide layer formed by vapor depositing silicon oxide by chemical vapor deposition. That is, the light detection array 5 is a light detection array 5 chip manufactured by a silicon-based semiconductor process.

Further, this application embodiment optical fingerprint identification module still include: a filter layer 47. The filter layer 47 is disposed between the microlens unit 11 and the photosensitive pixel array. In some embodiments, the filter layer 47 can be formed on the surface of the light detection array 5 by an evaporation process. Of course, the filter layer 47 may be formed on the surface of the photodetector array 5 by other processes, for example, sputtering, deposition, or other processes.

Further, a filter layer 47 is formed on a surface of the first light splitting unit 19 facing the microlens 41. As shown in fig. 1, a filter layer 47 for filtering infrared light is further provided between the aperture stop layer 13 and the first light splitting unit 19. Fig. 1 illustrates the target signal light as the visible light signal light, but the filter layer 47 filters out the optical signal in the visible light band when the target signal light is the invisible light. Therefore, the filter layer 47 can prevent the optical signal of the non-target wavelength band from entering the first light transmission portion 17 of the first light splitting unit 19, and further prevent the optical signal of the non-target wavelength band from irradiating on the photosensitive pixel array to affect the fingerprint identification of the photosensitive pixel array.

In one embodiment, the optical fingerprint identification module of this application embodiment still includes: and a second light splitting unit 23. The second light splitting unit 23 is provided below the optical structure portion. Meanwhile, the second light splitting unit 23 is located below the first light splitting unit 19. Specifically, the second spectroscopic unit 23 is located below the focal plane corresponding to the microlens 41 of the microlens unit 11. For example, as shown in fig. 2, the second light splitting unit 23 is located below the first light splitting unit 19. So that the light passing through the first light splitting unit 19 can be irradiated on the second light splitting unit 23 as the light travels from top to bottom. The second light splitting unit 23 includes a second light shielding body 25 and a plurality of second light transmitting portions 27 disposed on the second light shielding body 25. For example, as shown in fig. 3, second light transmitting portion 27 is located at the center of second light splitting unit 23. The second light shielding body 25 is located outside the second light transmitting portion 27. The second light-shielding body 25 is used to prevent light from passing through. The second light-transmitting portion 27 is for allowing light to pass therethrough. The second light shielding body 25 can further filter the non-target light signals which pass through the first light transmission part 17 at other angles, and helps to improve the imaging quality of the fingerprint image of the light detection array 5.

Specifically, a through hole is provided in the center of the second light-shielding body 25 to pass through the second light-shielding body. The through-hole is open toward the first light splitting unit 19 so that the through-hole can be used for light to pass through. That is, the through hole forms the second light transmitting portion 27. Of course, the second light transmission part 27 is not limited to a through hole. Other configurations are also possible. For example, a transparent material is provided on the second light splitting unit 23. For example, the transparent material is glass. So that light can pass through the transparent material. That is, in this case, the second light transmission portion 27 is formed of the transparent material.

Further, the second light-shielding body 25 may be black. The black second light-shielding body 25 can absorb the light of various colors irradiated thereon, thus achieving the purpose of shielding the light.

Further, the second light splitting unit 23 may be formed of photoresist. Of course, the second light splitting unit 23 is not limited to be formed using photoresist. Other materials, such as metals, etc., are also possible and are not specified in this application.

Further, in one embodiment, the optical structure is partially integrated on the photosensitive region 311 integrally disposed on the photosensitive pixel array, and is in a dissociated structure with the photo detector array 5. Both of which are integrally formed by adhering the optical structure portion and the light detection array 5 by a third party adhesive material. In particular, the optical structure portion is attached to the array of photosensitive pixels by an optical glue. In such embodiments, the optical structure portion is not fabricated using semiconductor processes. In this embodiment, since the optical structure does not occupy the semiconductor process for fabricating the photodetector array 5, the fabrication cost of the optical fingerprint identification module can be greatly reduced.

In this embodiment, the specific structure of the film layer of the optical structure portion may be one of the ways described in this paragraph. The method specifically comprises the following steps: the second medium layer 53 between the aperture stop layer 13 and the microlens unit 11 is a first carrier film. The aperture stop layer 13 and the microlens unit 11 are respectively disposed on the upper and lower sides of the first carrier film. In such embodiments, the second dielectric layer 53 does not fill the light-transmissive holes 43 into the aperture layer 13. Of course, in such embodiments, the first medium layer 51 between the aperture stop layer 13 and the first light splitting unit 19 is a second carrier film. The aperture stop layer 13 and the first light splitting unit 19 are respectively disposed on the upper and lower sides of the second carrier film. In such embodiments, the first dielectric layer 51 does not fill the opening formed into the first light-transmitting portion 17 of the first light splitting unit 19.

Since in the embodiments of the type described above the optical structure portion is fabricated using a film structure rather than a semiconductor process, the second light splitting unit 23 in the embodiments of the type described above is not fabricated as much as possible in order to minimize the complexity of fabricating the optical structure layer or to cause the thickness of the optical structure portion to increase too much. For this purpose, the second beam splitting unit 23 as described above needs to be integrated into the light detection array 5, i.e. below the optical structure portion.

Under the guidance of the technical spirit that the second light splitting unit 23 needs to be integrated into the light detection array 5, the second light splitting unit 23 and the light detection array 5 include the following feasible arrangement schemes:

the first embodiment is as follows: the first spectroscopic unit 19 is integrated inside the light detection array 5.

Example two: the first spectroscopic unit 19 is integrated outside the light detection array 5.

Under the main technical solution of the first embodiment, the second light splitting unit 23 includes the following feasible implementation manners:

the second light splitting unit 23 is formed in the photo detector array 5 and located above the photosensitive pixel array. Specifically, the second light splitting unit 23 is disposed on any one of several metal layers of the photosensitive region 311 of the photosensitive pixel array. Specifically, as shown in fig. 4, the method includes: the second light splitting unit 23 is formed on the middle second metal layer 312 b. Or the second light splitting unit 23 is formed on the first metal layer 312a of the top layer. Alternatively, the second light splitting unit 23 is formed on the underlying third metal layer 312 c.

Under the main technical solution of the second embodiment, the second light splitting unit 23 includes the following feasible implementation manners: the second light splitting unit 23 is made of a metal material and is formed above the light detection array 5. Specifically, the second spectroscopic unit 23 is not limited to be made of a metal layer existing in the photodetector array 5, and may be made of only a metal layer or other material that only functions optically. In practice, only in the semiconductor manufacturing process of the photo detection array 5, if the second light splitting unit 23 needs to be integrated into the upper surface of the photosensitive region 311 of the photo detection array 5, the second light splitting unit 23 is manufactured by using a metal layer, which is more compatible with the semiconductor manufacturing process, and an introduced process material is not needed, thereby reducing the difficulty of manufacturing the layer by using the semiconductor back-end process.

Under the main technical solution of the second embodiment, the second light splitting unit 23 includes the following feasible implementation manners: the second light splitting unit 23 is integrated with the optical structure portion outside the light sensing region 311 integrally adhered to the light sensing pixel array. Specifically, the second light splitting unit 23 is integrated with the optical structure portion in a film structure and is adhered to the passivation layer 7 of the photosensitive pixel by a third party adhesive material. Alternatively, the second light splitting unit 23 may be formed on the surface of the passivation layer 7 of the photodetecting array 5 by using a semiconductor process, and in this embodiment, the optical fingerprint identification module according to this embodiment further includes: and a third dielectric layer. The third medium layer is arranged between the second light splitting unit 23 and the light detection array 5. The third dielectric layer is filled in the opening formed by the second light-transmitting portion 27.

Further, the second light transmission portions 27 correspond to the first light transmission portions 17 one by one or one second light transmission portion 27 corresponds to a plurality of first light transmission portions 17. For example, as in the embodiment illustrated in fig. 2, one second light-transmitting portion 27 corresponds to only one first light-transmitting portion 17. Since one first light-transmitting portion 17 corresponds to one microlens 41, one second light-transmitting portion 27 may correspond to only one microlens 41. The line connecting the second light transmission portion 27 and the first light transmission portion 17 may be at a predetermined angle corresponding to the signal light within the range of the target angle to be realized by the microlens.

Further, the first light transmission portion 17 and the second light transmission portion 27 each have a pore diameter of 1 μm. And the distance between the first and second light transmission portions 17 and 27 is 1.2 μm. So that the collimating effect of the light can be improved by defining the aperture of the first and second light transmission portions 17 and 27. And the requirement for the collimation effect of the first light transmission part 17 and the second light transmission part 27 can be balanced and the thickness requirement of the optical fingerprint identification module set can be reduced by limiting the distance between the first light transmission part 17 and the second light transmission part 27.

The embodiment of the application also provides electronic equipment which can be provided with the optical fingerprint identification module in any one of the above embodiments. The electronic device may include, but is not limited to, a mobile smartphone, a tablet electronic device, a computer, a GPS navigator, a personal digital assistant, a smart wearable device, and so forth.

It should be noted that, in the description of the present invention, the terms "first", "second", and the like are used for descriptive purposes only and for distinguishing similar objects, and no order is shown between the two, and no indication or suggestion of relative importance is understood. In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are hereby incorporated by reference for all purposes. The omission in the foregoing claims of any aspect of the subject matter that is disclosed herein is not intended to forego such subject matter, nor should the applicants be construed as having contemplated such subject matter as being part of the disclosed subject matter.

Claims (20)

1. An optics fingerprint identification module, its characterized in that, it includes:

an optical structure portion including a microlens unit, an aperture stop layer, and a first light splitting unit; the micro lens unit comprises a micro lens array formed by a plurality of micro lenses, the first light splitting unit comprises a first light shielding body and a first light transmitting part arranged on the first light shielding body, the first light splitting unit is positioned near a focal plane of the micro lens unit, and the first light transmitting part corresponds to the micro lenses in the micro lens array one by one; the aperture diaphragm layer is provided with a plurality of light transmission holes and is arranged between the micro lens and the first light splitting unit;

and the light detection array is arranged below the optical structure part and comprises a photosensitive pixel array which is used for receiving the light signal carrying the fingerprint information and transmitted by the optical structure part.

2. The optical fingerprint recognition module of claim 1 wherein: the aperture diaphragm layer is closely attached to the micro-lens unit and is positioned below the micro-lens unit.

3. The optical fingerprint recognition module of claim 1 further comprising: and the first medium layer is arranged between the aperture diaphragm layer and the first light splitting unit.

4. The optical fingerprint recognition module of claim 3 wherein: the first medium layer is filled in the opening formed by the first light transmission part of the first light splitting unit.

5. The optical fingerprint recognition module of claim 1 further comprising: and a second medium layer with preset thickness is arranged between the aperture diaphragm layer and the micro-lens layer.

6. The optical fingerprint recognition module of claim 1 further comprising: a filter layer disposed between the microlens unit and the photosensitive pixel array.

7. The optical fingerprint recognition module of claim 6 wherein: the filter layer is formed on the surface of the first light splitting unit facing the micro lens.

8. The optical fingerprint recognition module of claim 6 wherein: the filter layer is plated on the surface of the light detection array.

9. The optical fingerprint recognition module of claim 1 wherein: the optical structure part is integrated on a photosensitive area integrally arranged on the photosensitive pixel array.

10. The optical fingerprint recognition module of claim 9 wherein: the optical structure portion is attached to the array of photosensitive pixels by an optical adhesive.

11. The optical fingerprint recognition module of claim 1 further comprising: a second light splitting unit disposed below the optical structure portion; the second light splitting unit comprises a second light shielding body and a plurality of second light transmitting parts arranged on the second light shielding body.

12. The optical fingerprint recognition module of claim 11 wherein: the second light splitting unit is formed in the light detection array and is located above the photosensitive pixel array.

13. The optical fingerprint recognition module of claim 12 wherein: the second light splitting unit is arranged on any one of the plurality of metal layers of the photosensitive area of the photosensitive pixel array.

14. The optical fingerprint recognition module of claim 11 wherein: the second light splitting unit is arranged outside the light detection array.

15. The optical fingerprint recognition module of claim 14 wherein: the second light splitting unit is made of metal materials and is formed above the light detection array.

16. The optical fingerprint recognition module of claim 14 wherein: the second light splitting unit and the optical structure part are integrated outside a photosensitive area integrally adhered to the photosensitive pixel array.

17. The optical fingerprint recognition module of claim 14 further comprising: and the third medium layer is arranged between the second light splitting unit and the light detection array and is filled in the opening formed by the second light transmission part.

18. The optical fingerprint recognition module of claim 11 wherein: the second light transmission parts correspond to the first light transmission parts one by one or one second light transmission part corresponds to a plurality of first light transmission parts.

19. The optical fingerprint recognition module of claim 1 wherein: the light detection array is a light detection array chip manufactured by a silicon-based semiconductor process.

20. An electronic device, characterized in that the electronic device is provided with an optical fingerprint recognition module according to any one of claims 1 to 19.

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