WO2021073016A1 - 指纹识别装置和电子设备 - Google Patents

指纹识别装置和电子设备 Download PDF

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Publication number
WO2021073016A1
WO2021073016A1 PCT/CN2020/073901 CN2020073901W WO2021073016A1 WO 2021073016 A1 WO2021073016 A1 WO 2021073016A1 CN 2020073901 W CN2020073901 W CN 2020073901W WO 2021073016 A1 WO2021073016 A1 WO 2021073016A1
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WIPO (PCT)
Prior art keywords
fingerprint
light
fingerprint identification
pixel
units
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PCT/CN2020/073901
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English (en)
French (fr)
Inventor
蒋鹏
马明
Original Assignee
深圳市汇顶科技股份有限公司
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Application filed by 深圳市汇顶科技股份有限公司 filed Critical 深圳市汇顶科技股份有限公司
Priority to CN202080001559.XA priority Critical patent/CN111837131B/zh
Publication of WO2021073016A1 publication Critical patent/WO2021073016A1/zh

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14678—Contact-type imagers
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V10/00—Arrangements for image or video recognition or understanding
    • G06V10/10—Image acquisition
    • G06V10/12—Details of acquisition arrangements; Constructional details thereof
    • G06V10/14—Optical characteristics of the device performing the acquisition or on the illumination arrangements
    • G06V10/145—Illumination specially adapted for pattern recognition, e.g. using gratings
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V10/00—Arrangements for image or video recognition or understanding
    • G06V10/10—Image acquisition
    • G06V10/12—Details of acquisition arrangements; Constructional details thereof
    • G06V10/14—Optical characteristics of the device performing the acquisition or on the illumination arrangements
    • G06V10/147—Details of sensors, e.g. sensor lenses
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
    • G06V40/10—Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
    • G06V40/12—Fingerprints or palmprints
    • G06V40/13—Sensors therefor
    • G06V40/1318—Sensors therefor using electro-optical elements or layers, e.g. electroluminescent sensing
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
    • G06V40/10—Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
    • G06V40/12—Fingerprints or palmprints
    • G06V40/13—Sensors therefor
    • G06V40/1324—Sensors therefor by using geometrical optics, e.g. using prisms
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/0006—Arrays
    • G02B3/0037—Arrays characterized by the distribution or form of lenses
    • G02B3/0056—Arrays characterized by the distribution or form of lenses arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses

Definitions

  • This application relates to the field of optical fingerprint technology, and more specifically, to a fingerprint identification device and electronic equipment.
  • the fingerprint recognition technology under the screen is to set the fingerprint recognition device under the display screen, and realize fingerprint recognition by collecting fingerprint images.
  • the fingerprint identification device may converge the received light signals to the pixel array in the photoelectric sensor through a microlens array, and the photoelectric sensor generates a fingerprint image based on the light signal received by the pixel array, and then performs fingerprint recognition.
  • the microlens array in the fingerprint identification device is located directly above the pixel array, and one microlens corresponds to a pixel unit, that is, each microlens in the microlens array focuses the received light to the same microlens In the corresponding pixel unit, a plurality of pixel units are arranged in an array.
  • the embodiments of the present application provide a fingerprint identification device and electronic equipment, which can improve the performance of the fingerprint identification device.
  • a fingerprint identification device which is suitable for under the display screen to realize under-screen optical fingerprint identification.
  • the fingerprint identification device includes N fingerprint identification units arranged in close rows, where N is a positive integer; the N fingerprints
  • Each fingerprint recognition unit in the recognition unit includes: a circular microlens; at least two light-blocking layers are arranged under the circular microlens, and each of the at least two light-blocking layers is provided with a light blocking layer.
  • the light holes form M light guide channels in different directions, and M is a positive integer greater than 1; M pixel units are arranged under the at least two light-blocking layers, and the M pixel units are respectively located in the M light guides The bottom of the channel; where the light signals returned after being reflected or scattered from the finger above the display screen are converged by the circular microlens, and the M target fingerprint light signals in different directions are respectively transmitted to the M light guide channels.
  • the M pixel units and the M target fingerprint light signals are used to detect the fingerprint information of the finger; each of the N fingerprint recognition units is adjacent to six fingerprint recognition units, and the six fingerprint recognition units
  • the connecting lines of the centers of the six circular microlenses in the circle form a regular hexagon.
  • a circular microlens corresponds to M pixel units, and the M pixel units are respectively collected by the circular microlens and passed through M
  • the fingerprint light signals in the M directions of the light guide channel are respectively received by the M pixel units.
  • the amount of light entering the fingerprint identification device can be increased, the exposure time can be reduced, and the field of view of the fingerprint identification device can be increased.
  • the angle of the fingerprint light signal received by the pixel unit is determined by the relative positional relationship between the pixel unit and the microlens.
  • the pixel unit shifts farther from the center of the microlens, the fingerprint light signal received by the pixel unit The greater the angle. Therefore, by flexibly setting the position of the pixel unit, the pixel unit can receive fingerprint light signals at a large angle, which greatly improves the recognition problem of dry fingers, and can reduce the thickness of the optical path in the fingerprint recognition unit, thereby reducing the fingerprint recognition device Thickness, reduce process cost.
  • the plurality of circular microlenses in the fingerprint identification device are arranged in close rows, which can increase the duty ratio of the plurality of circular microlenses and increase the progress of the fingerprint identification device. The amount of light further improves the quality of fingerprint images and fingerprint recognition performance.
  • the N fingerprint identification units include N ⁇ M pixel units for receiving M fingerprint light signals in different directions to form M fingerprint images.
  • N pixel units are used to receive fingerprint light signals in one direction to form N pixel values, and the N pixel values are used to form a fingerprint image in the M fingerprint images, where the N pixel units belong to N respectively Fingerprint identification unit; at least one of the M fingerprint images is used for fingerprint identification.
  • the arrangement of the N pixel units is the same as the arrangement of the N circular microlenses in the N fingerprint identification units.
  • the fingerprint identification device further includes a processing unit; the processing unit is configured to insert an interpolation pixel between each adjacent W pixel values of the N pixel values of the N pixel units, In order to obtain a fingerprint image with a square arrangement of pixel values, where W is a positive integer greater than 1.
  • W 4
  • the interpolation pixel is the average value of each adjacent 4 pixel values in the N pixel values.
  • the processing unit is used to up-sample or down-sample the M fingerprint images to adjust the aspect ratio of the M fingerprint images to form M optimized fingerprint images.
  • the processing unit is configured to obtain the first optimized fingerprint image and the second optimized fingerprint image in the M optimized fingerprint images, and obtain the first region in the first optimized fingerprint image; For the pixel value of the first area, determine the second area closest to the first area in the second optimized fingerprint image; calculate the difference between the coordinates of the first area and the coordinates of the second area, and move the first area
  • the optimized fingerprint image and the second optimized fingerprint image form a first reconstructed image; wherein the first reconstructed image is used to form a target reconstructed image, and the target reconstructed image is an image formed by reconstructing the optimized fingerprint image ,
  • the target reconstructed image is used for fingerprint recognition.
  • the processing unit is used to move the M optimized fingerprint images to combine to form a reconstructed image, and adjust the moving distance of the M fingerprint images according to the quality parameters of the reconstructed image to A target reconstructed image is formed, and the target reconstructed image is used for fingerprint recognition.
  • the distance between the centers of two adjacent circular microlenses is less than 75 ⁇ m.
  • the direction of one light guide channel among the directions of the M light guide channels is perpendicular to the display screen, and the directions of the other M-1 light guide channels are inclined with respect to the display screen; or, The directions of the M light guide channels are all inclined relative to the display screen.
  • angles between the M light guide channels and the display screen are between 30° and 90°.
  • the included angles of the M light guide channels and the display screen are the same.
  • the included angle of the projection of the two light guide channels of the M light guide channels on the plane where the plurality of pixel units are located is 90 degrees.
  • the M pixel units respectively include M photosensitive regions, and the M photosensitive regions are respectively located at the bottom of the M light guide channels.
  • At least one of the M photosensitive areas is arranged deviating from the center of the pixel unit where it is located.
  • the at least one photosensitive area deviates in a direction away from the center of the circular microlens.
  • the M pixel units include a first pixel unit, the first pixel unit includes a first photosensitive area, and both the first pixel unit and the first photosensitive area are quadrilaterals; wherein, the The length and width of the first pixel unit are respectively L and W, and the length and width of the first photosensitive area are both greater than or equal to 0.1 ⁇ W, W ⁇ L, and both W and L are positive numbers.
  • the area of the first photosensitive region is greater than or equal to 95% of the area of the first pixel unit.
  • the angle between the target fingerprint optical signal and the vertical direction, the angle between the first target fingerprint optical signal in the M target fingerprint optical signals and the vertical direction is greater than the angle between the other target fingerprint optical signals in the M target fingerprint optical signals and the vertical direction
  • the included angle, the vertical direction is the direction perpendicular to the display screen.
  • the bottom light-blocking layer of the at least two light-blocking layers is provided with M light-passing holes corresponding to the M pixel units, respectively.
  • the bottom light-blocking layer of the at least two light-blocking layers is a metal wiring layer on the surface of the M pixel units.
  • the apertures of the light-passing holes in the M light guide channels are sequentially reduced from top to bottom.
  • the M light guide channels overlap the light passing holes in the top light blocking layer of the at least two light blocking layers.
  • the fingerprint identification unit further includes: a transparent medium layer; wherein the lens medium layer is used to connect the circular microlens, the at least two light blocking layers, and the M pixel units.
  • the fingerprint identification unit further includes: an optical filter layer; wherein the optical filter layer is disposed in the light path between the display screen and the plane where the M pixel units are located, and is used to filter non-targets.
  • the optical signal of the waveband is transmitted through the optical signal of the target waveband.
  • the optical filter layer is integrated on the surface of the M pixel units.
  • the optical filter layer is disposed between the bottom light-blocking layer of the at least two light-blocking layers and the plane where the M pixel units are located.
  • the distance between the fingerprint identification device and the display screen is 0 to 1 mm.
  • an electronic device including the fingerprint identification device as in the first aspect or any possible implementation of the first aspect, the fingerprint identification device is arranged under the display screen to implement an under-screen optical fingerprint Recognition.
  • the distance between the fingerprint identification device and the display screen is 0 to 1 mm.
  • the above-mentioned fingerprint identification device is provided in an electronic device, and the fingerprint identification performance of the fingerprint identification device is improved, thereby improving the fingerprint identification performance of the electronic device.
  • FIG. 1 is a schematic diagram of the structure of an electronic device to which an embodiment of the application is applicable.
  • FIGS. 2 and 3 are a schematic cross-sectional view and a schematic top view of a fingerprint identification device according to an embodiment of the present application.
  • Fig. 4 is a schematic top view of a fingerprint identification device according to an embodiment of the present application.
  • Fig. 5a is a schematic three-dimensional structural diagram of a fingerprint identification unit according to an embodiment of the present application.
  • Fig. 5b is a top view of the fingerprint identification unit in Fig. 5a.
  • Fig. 5c is a top view of the close-packed arrangement of a plurality of fingerprint identification units in Fig. 5a.
  • Fig. 6a is another schematic three-dimensional structural diagram of a fingerprint identification unit according to an embodiment of the present application.
  • Fig. 6b is a top view of the fingerprint identification unit in Fig. 6a.
  • Fig. 6c is a top view of the close-packed arrangement of a plurality of fingerprint identification units in Fig. 6a.
  • Fig. 7a is another schematic three-dimensional structural diagram of a fingerprint identification unit according to an embodiment of the present application.
  • Fig. 7b is a top view of the fingerprint identification unit in Fig. 7a.
  • Fig. 7c is a top view of the close-packed arrangement of a plurality of fingerprint identification units in Fig. 7a.
  • FIGS. 8a and 8b are schematic diagrams of the arrangement of multiple first pixel units and multiple second pixel units in two multiple fingerprint identification units according to an embodiment of the present application.
  • Fig. 9 is a schematic diagram of an arrangement of multiple first pixel units, multiple second pixel units, multiple third pixel units, and multiple fourth pixel units in multiple fingerprint identification units according to an embodiment of the present application.
  • Fig. 10 is a data structure of original pixel values of a plurality of first pixel units according to an embodiment of the present application.
  • FIG. 11 is a data structure of a square array arrangement formed after interpolation processing according to an embodiment of the present application.
  • FIG. 12 is a data structure of original pixel values of another plurality of first pixel units according to an embodiment of the present application.
  • FIG. 13 is a data structure of another square array arrangement formed after interpolation processing according to an embodiment of the present application.
  • Fig. 14 is a schematic top view of a fingerprint identification unit according to an embodiment of the present application.
  • Fig. 15 is a schematic cross-sectional view of the fingerprint identification unit in Fig. 14 along the direction A-A'.
  • Fig. 16 is a schematic top view of another fingerprint identification unit according to an embodiment of the present application.
  • Fig. 17 is a schematic cross-sectional view of the fingerprint identification unit in Fig. 16 along the A-A' direction.
  • Fig. 18 is a schematic top view of another fingerprint identification unit according to an embodiment of the present application.
  • Fig. 19 is a schematic top view of another fingerprint identification unit according to an embodiment of the present application.
  • Fig. 20 is a schematic top view of another fingerprint identification unit according to an embodiment of the present application.
  • Fig. 21 is a schematic top view of another fingerprint identification unit according to an embodiment of the present application.
  • Fig. 22 is a schematic structural diagram of an electronic device according to an embodiment of the present application.
  • optical fingerprint systems including but not limited to optical fingerprint identification systems and products based on optical fingerprint imaging.
  • the embodiments of this application only take optical fingerprint systems as an example for illustration, but should not be implemented in this application.
  • the examples constitute any limitation, and the examples of this application are also applicable to other systems that use optical imaging technology.
  • the optical fingerprint system provided in the embodiments of this application can be applied to smart phones, tablet computers, and other mobile terminals with display screens or other electronic devices; more specifically, in the above electronic devices, fingerprint identification
  • the device may specifically be an optical fingerprint device, which may be arranged in a partial area or an entire area under the display screen, thereby forming an under-display optical fingerprint system.
  • the fingerprint identification device can also be partially or fully integrated into the display screen of the electronic device to form an in-display optical fingerprint system.
  • the electronic device 10 includes a display screen 120 and an optical fingerprint device 130, wherein the optical fingerprint device 130 is disposed in a partial area under the display screen 120.
  • the optical fingerprint device 130 includes an optical fingerprint sensor, and the optical fingerprint sensor includes a sensing array 133 having a plurality of optical sensing units 131, and the area where the sensing array 133 is located or its sensing area is the fingerprint detection area 103 of the optical fingerprint device 130. As shown in FIG. 1, the fingerprint detection area 103 is located in the display area of the display screen 120.
  • the optical fingerprint device 130 can also be arranged in other positions, such as the side of the display screen 120 or the non-transmissive area at the edge of the electronic device 10, and at least part of the display area of the display screen 120 is designed through the optical path.
  • the optical signal is guided to the optical fingerprint device 130, so that the fingerprint detection area 103 is actually located in the display area of the display screen 120.
  • the area of the fingerprint detection area 103 may be different from the area of the sensing array of the optical fingerprint device 130.
  • the optical fingerprint can be made The area of the fingerprint detection area 103 of the device 130 is larger than the area of the sensing array of the optical fingerprint device 130.
  • the fingerprint detection area 103 of the optical fingerprint device 130 can also be designed to be substantially the same as the area of the sensing array of the optical fingerprint device 130.
  • the electronic device 10 with the above structure does not need to reserve space on the front side to set the fingerprint button (such as the Home button), so that a full-screen solution can be adopted, that is, the display area of the display screen 120 can be basically Extend to the front of the entire electronic device 10.
  • the optical fingerprint device 130 includes a light detecting portion 134 and an optical component 132.
  • the light detecting portion 134 includes a sensing array and a reading circuit electrically connected to the sensing array.
  • Other auxiliary circuits which can be fabricated on a chip (Die) through a semiconductor process, such as an optical imaging chip or an optical fingerprint sensor.
  • the sensing array is specifically a photodetector array, which includes a plurality of arrays distributed
  • the photodetector can be used as the above-mentioned optical sensing unit; the optical component 132 can be arranged above the sensing array of the light detecting part 134, and it can specifically include a light guide layer or a light path guide structure and other optical elements.
  • the light guide layer or light path guide structure is mainly used to guide the reflected light reflected from the surface of the finger to the sensing array for optical detection.
  • the optical assembly 132 and the light detecting part 134 may be packaged in the same optical fingerprint component.
  • the optical component 132 and the optical detection part 134 can be packaged in the same optical fingerprint chip, or the optical component 132 can be arranged outside the chip where the optical detection part 134 is located, for example, the optical component 132 can be attached to the Above the chip, or part of the components of the optical assembly 132 are integrated into the above-mentioned chip.
  • the light guide layer or light path guiding structure of the optical component 132 has multiple implementation schemes.
  • the light guide layer may be specifically a collimator layer made on a semiconductor silicon wafer, which has multiple collimators.
  • the collimating unit can be specifically a small hole, the reflected light reflected from the finger, the light that is perpendicularly incident on the collimating unit can pass through and be received by the optical sensor unit below it, and the incident angle Excessive light is attenuated by multiple reflections inside the collimating unit, so each optical sensor unit can basically only receive the reflected light reflected by the fingerprint pattern directly above it, so the sensor array can detect the finger Fingerprint image.
  • the light guide layer or the light path guide structure may also be an optical lens (Lens) layer, which has one or more lens units, such as a lens group composed of one or more aspheric lenses, which is used for The reflected light reflected from the finger is condensed to the sensing array of the light detection part 134 below it, so that the sensing array can perform imaging based on the reflected light, thereby obtaining a fingerprint image of the finger.
  • the optical lens layer may further have a pinhole formed in the optical path of the lens unit, and the pinhole may cooperate with the optical lens layer to expand the field of view of the optical fingerprint device, so as to improve the fingerprint imaging effect of the optical fingerprint device 130.
  • the light guide layer or the light path guide structure may also specifically adopt a micro-lens (Micro-Lens) layer.
  • the micro-lens layer has a micro-lens array formed by a plurality of micro-lenses. The process is formed above the sensing array of the light detecting part 134, and each microlens may correspond to one of the sensing units of the sensing array, respectively.
  • other optical film layers may be formed between the micro lens layer and the sensing unit, such as a dielectric layer or a passivation layer. More specifically, a light blocking layer with micro holes may also be formed between the micro lens layer and the sensing unit. The micro-hole is formed between the corresponding micro-lens and the sensing unit.
  • the light blocking layer can block the optical interference between the adjacent micro-lens and the sensing unit, and make the light corresponding to the sensing unit converge into the micro-hole through the micro-lens And it is transmitted to the sensing unit through the micro-hole for optical fingerprint imaging.
  • a microlens layer can be further provided under the collimator layer or the optical lens layer.
  • the collimator layer or the optical lens layer is used in combination with the micro lens layer, the specific laminated structure or optical path may need to be adjusted according to actual needs.
  • the display screen 120 may adopt a display screen with a self-luminous display unit, such as an organic light-emitting diode (OLED) display screen or a micro-LED (Micro-LED) display screen.
  • a self-luminous display unit such as an organic light-emitting diode (OLED) display screen or a micro-LED (Micro-LED) display screen.
  • the optical fingerprint device 130 may use the display unit (ie, OLED light source) of the OLED display screen 120 located in the fingerprint detection area 103 as the excitation light source for optical fingerprint detection.
  • OLED light source the display unit of the OLED display screen 120 located in the fingerprint detection area 103.
  • the display screen 120 emits a beam of light 111 to the target finger 140 above the fingerprint detection area 103.
  • the light 111 is reflected on the surface of the finger 140 to form reflected light or scattered inside the finger 140.
  • the scattered light is formed.
  • the above-mentioned reflected light and scattered light are collectively referred to as reflected light. Because the ridge and valley of the fingerprint have different light reflection capabilities, the reflected light 151 from the fingerprint ridge and the reflected light 152 from the fingerprint valley have different light intensities. After the reflected light passes through the optical component 132, It is received by the sensor array 134 in the optical fingerprint device 130 and converted into a corresponding electrical signal, that is, a fingerprint detection signal; based on the fingerprint detection signal, fingerprint image data can be obtained, and fingerprint matching verification can be further performed, so that the electronic device 10 Realize the optical fingerprint recognition function.
  • the optical fingerprint device 130 may also use a built-in light source or an external light source to provide an optical signal for fingerprint detection.
  • the optical fingerprint device 130 may be suitable for non-self-luminous display screens, such as liquid crystal display screens or other passively-luminous display screens.
  • the optical fingerprint system of the electronic device 10 may also include an excitation light source for optical fingerprint detection.
  • the optical fingerprint device 130 can be specifically an infrared light source or a light source of invisible light of a specific wavelength, which can be arranged under the backlight module of the liquid crystal display or arranged in the edge area under the protective cover of the electronic device 10, and the optical fingerprint device 130 can be arranged with a liquid crystal panel or Under the edge area of the protective cover and guided by the light path so that the fingerprint detection light can reach the optical fingerprint device 130; or, the optical fingerprint device 130 can also be arranged under the backlight module, and the backlight module passes through the diffusion sheet, the brightness enhancement sheet,
  • the film layer such as the reflective sheet has holes or other optical designs to allow the fingerprint detection light to pass through the liquid crystal panel and the backlight module and reach the optical fingerprint device 130.
  • the optical fingerprint device 130 adopts a built-in light source or an external light source to provide an optical signal for fingerprint detection, the detection principle is the same as that described above.
  • the electronic device 10 further includes a transparent protective cover plate, which may be a glass cover plate or a sapphire cover plate, which is located above the display screen 120 and covers the front surface of the electronic device 10.
  • a transparent protective cover plate which may be a glass cover plate or a sapphire cover plate, which is located above the display screen 120 and covers the front surface of the electronic device 10.
  • the electronic device 10 may further include a circuit board 150 disposed under the optical fingerprint device 130.
  • the optical fingerprint device 130 can be adhered to the circuit board 150 through adhesive, and is electrically connected to the circuit board 150 through soldering pads and metal wires.
  • the optical fingerprint device 130 can realize electrical interconnection and signal transmission with other peripheral circuits or other components of the electronic device 10 through the circuit board 150.
  • the optical fingerprint device 130 can receive the control signal of the processing unit of the electronic device 10 through the circuit board 150, and can also output the fingerprint detection signal from the optical fingerprint device 130 to the processing unit or the control unit of the electronic device 10 through the circuit board 150 Wait.
  • the optical fingerprint device 130 may include only one optical fingerprint sensor.
  • the fingerprint detection area 103 of the optical fingerprint device 130 has a small area and a fixed position. Therefore, the user needs to perform fingerprint input Press the finger to a specific position of the fingerprint detection area 103, otherwise the optical fingerprint device 130 may not be able to collect fingerprint images, resulting in poor user experience.
  • the optical fingerprint device 130 may specifically include a plurality of optical fingerprint sensors; the plurality of optical fingerprint sensors may be arranged side by side under the display screen 120 in a splicing manner, and the sensing areas of the plurality of optical fingerprint sensors are common The fingerprint detection area 103 of the optical fingerprint device 130 is constituted.
  • the fingerprint detection area 103 of the optical fingerprint device 130 may include multiple sub-areas, and each sub-area corresponds to the sensing area of one of the optical fingerprint sensors, so that the fingerprint collection area 103 of the optical fingerprint device 130 can be extended to display
  • the main area of the lower half of the screen is extended to the area where the finger is habitually pressed, so as to realize the blind fingerprint input operation.
  • the fingerprint detection area 103 can also be extended to half of the display area or even the entire display area, thereby realizing half-screen or full-screen fingerprint detection.
  • the sensing array in the optical fingerprint device may also be referred to as a pixel array
  • the optical sensing unit or sensing unit in the sensing array may also be referred to as a pixel unit.
  • optical fingerprint device in the embodiments of the present application may also be referred to as an optical fingerprint identification module, a fingerprint identification device, a fingerprint identification module, a fingerprint module, a fingerprint acquisition device, etc., and the above terms can be replaced with each other.
  • Figures 2 and 3 show a schematic cross-sectional view and a schematic top view of a fingerprint identification device.
  • the fingerprint identification device 200 includes a microlens array 210, at least one light blocking layer 220 and a pixel array 230.
  • the microlens array 210 is located directly above the pixel array 230 and at least one layer of light blocking layer 220, and one microlens 211 corresponds to a pixel unit 231, that is, each microlens 211 in the microlens array 210 passes the received light at least The small holes 221 of the light blocking layer 220 are focused into the pixel unit 231 corresponding to the same micro lens 211.
  • the optical signal received by each microlens 211 is mainly a fingerprint optical signal incident perpendicular to the microlens array 210 after being reflected or scattered by a finger above the display screen.
  • the pixel units 231 in the pixel array 230 are arranged periodically, and the photosensitive area 2311 of each pixel unit 231 in the pixel array 230 is arranged at the center of the same pixel unit, so as to improve the sensitivity of the photosensitive area. Duty cycle.
  • the multiple microlenses 211 in the microlens array 210 correspond to the multiple pixel units 231 in the pixel array 230 one-to-one, and the photosensitive regions 2311 of the multiple pixel units 231 in the pixel array 230 are periodically arranged and uniformly distributed.
  • the photosensitive area of the pixel array 230 is affected by the size of the microlens array 210, and the thickness of the fingerprint identification device 200 is relatively large, which further increases the processing difficulty, cycle and cost of the optical path of the fingerprint identification device 200.
  • the fingers are usually dry and the cuticle is uneven. When it is pressed on the display screen, local areas of the fingers will have poor contact . When the dry finger is not in contact with the display screen, the fingerprint ridge and valley of the fingerprint image in the vertical direction formed by the fingerprint identification device 200 have poor contrast, and the image is blurred to the point where the fingerprint lines cannot be distinguished. Finger fingerprint recognition performance is poor.
  • a plurality of circular microlenses in the microlens array 210 are arranged in a square array, and the centers of four adjacent circular microlenses form a square.
  • two adjacent circular microlenses are tangent to each other.
  • the gap is also called a critical dimension (CD).
  • CD critical dimension
  • the effective condensing area in the area where the microlens array 210 is located is the sum of the areas of the multiple circular microlenses.
  • the circular microlens can increase the field of view. Receive a larger range of optical signals, thereby increasing the intensity of the received optical signals per unit area.
  • the gaps between the plurality of circular microlenses in the microlens array 210 are not light-condensing areas, and have no light-gathering effect, which cannot increase the intensity of the received light signal per unit area.
  • the ratio of the sum of the area of a plurality of circular microlenses to the area of the microlens array, or the ratio of the sum of the areas of a plurality of circular microlenses to the area of the pixel array is also written as
  • the duty cycle of the microlens can be used to characterize the ability of the microlens array to receive optical signals. The larger the duty cycle, the more areas the microlens array uses to converge the optical signals, and the light intensity increases.
  • the duty ratio of the microlens array 210 is the ratio of the area of a circular microlens in a unit period area to the area of the area where it is located.
  • the CD value between adjacent circular microlenses is 0, and the duty cycle of the microlens array 230 is 78.54%.
  • the CD value between adjacent circular microlenses is 78.54%.
  • the CD value is greater than 0, the duty cycle of the microlens array 230 is less than 78.54% in the ideal case, and the area of the microlens used for condensing light is not large, so the intensity of the light signal received by the pixel array is not large.
  • the light input of the device 200 is relatively small, and the exposure time is long.
  • a fingerprint identification device which can increase the light input of the fingerprint identification device, reduce the exposure time, increase the optical resolution and the optical field of view, and further optimize the recognition performance of dry fingers. Reduce the thickness of the fingerprint identification device.
  • FIG 4 is a schematic top view of a fingerprint identification device 300 provided by an embodiment of the present application.
  • the fingerprint identification device 300 is suitable for under the display screen to realize under-screen optical fingerprint identification.
  • the fingerprint identification device 300 may include N fingerprint identification units 301 arranged in a close-packed arrangement.
  • the close-packed arrangement may also be referred to as a hexagonal arrangement, where N is a positive integer.
  • each fingerprint identification unit 301 of the N fingerprint identification units 301 includes a circular microlens, and the N fingerprint identification units 301 include N circular microlenses, and the N circular microlenses
  • the lens is arranged in the same manner as the N fingerprint identification units, and is also arranged in close rows. As shown in FIG. 4, the fingerprint identification unit 301 located in the center is adjacent to the surrounding six fingerprint identification units 301, and the lines connecting the centers of the circular microlenses in the six fingerprint identification units 301 form a regular hexagon.
  • each of the N fingerprint recognition units is adjacent to six fingerprint recognition units, and the lines of the centers of the six circular microlenses in the six fingerprint recognition units constitute a regular hexagon shape.
  • the number of N fingerprint identification units in the embodiment of the present application is relatively large, and the whole of the N circular microlenses in the N fingerprint identification units generally forms a regular pattern, for example, a pattern such as a quadrilateral.
  • multiple edge fingerprint recognition units are also provided around the entire N fingerprint recognition units, and the structure of each edge fingerprint recognition unit in the multiple edge fingerprint recognition units is the same as that of the N fingerprint recognition units.
  • the number of adjacent fingerprint identification units of the plurality of edge fingerprint identification units is less than six, but the fingerprint identification device in the embodiment of the present application may also include the plurality of edge fingerprint identification units, so that all fingerprint identification units form a rule as a whole Graphics, for example, quadrilaterals and other graphics.
  • the distance between any two adjacent circular microlenses in the plurality of circular microlenses is equal.
  • any two adjacent circular microlenses in the plurality of circular microlenses are tangent, and the distance between the two adjacent circular microlenses is zero.
  • the plurality of circular microlenses are arranged alternately.
  • the gap is determined by the critical dimension CD in the manufacturing process.
  • the plurality of circular microlenses are arranged alternately, and the CD gap between any two adjacent circular microlenses in the plurality of circular microlenses is equal.
  • the vertex of the rhombus is located at the center of the four circular microlenses, and the rhombus area includes a complete circular microlens.
  • the calculation formula for the duty cycle D of the microlens array 310 is :
  • R is the radius of the circular microlens
  • a is the CD value between two adjacent circular microlenses.
  • the duty cycle of the N circular microlens arrays in the fingerprint identification device 300 is:
  • the duty cycle of the N circular microlens arrays in the fingerprint identification device 300 is:
  • the duty cycle of the N circular microlenses is greater than the duty cycle of the microlens array 210 in FIG. 3.
  • the multiple circular microlenses can be increased.
  • the duty ratio of the microlens increases the amount of light entering the fingerprint identification device, thereby improving the quality of fingerprint images and fingerprint identification performance.
  • each fingerprint identification unit 301 of the N fingerprint identification units in the embodiment of the present application also includes:
  • At least two light-blocking layers are arranged under the circular microlens, each of the at least two light-blocking layers is provided with light-passing holes to form M light-guiding channels in different directions, and M is greater than A positive integer of 1;
  • M pixel units are arranged under the at least two light blocking layers, and the M pixel units are distributed at the bottom of the M light guide channels;
  • the light signals returned from the finger above the display screen after being reflected or scattered are converged by the circular microlens, and the M target fingerprint light signals in different directions are respectively transmitted to the above M pixel units through the above M light guide channels,
  • the M target fingerprint light signals are used to detect fingerprint information of the finger.
  • the above-mentioned circular microlenses may be various lenses with a converging function, which are used to increase the field of view and increase the amount of light signals transmitted to the pixel unit.
  • the material of the circular microlens is transparent material, such as resin, glass and so on.
  • the M pixel units may be a type of photoelectric conversion unit.
  • the pixel unit may include a complementary metal oxide semiconductor (Complementary Metal Oxide Semiconductor, CMOS) device, specifically including a photodiode (PD) and a CMOS switch tube, etc., where the photodiode is composed of a PN junction
  • CMOS complementary metal oxide semiconductor
  • the composed semiconductor device has unidirectional conductivity characteristics, which can convert the received optical signal into a corresponding electrical signal, thereby realizing the conversion from optical image to electrical image.
  • the CMOS switch tube is used to receive the control signal to control the work of the photodiode, and can Used to control the electrical signal of the output photodiode.
  • At least two light-blocking layers are formed as a medium layer between the circular microlens and the M pixel units, which may be opaque organic material layers or metal layers. Perform pinhole image lithography and etching on the at least two light-blocking layers to form multiple light-passing holes.
  • the multiple light-passing holes on at least two layers can form multiple light guide channels in different directions. To guide light signals in different directions into the pixel unit located at the bottom of the light guide channel.
  • the direction of the light guide channel according to the requirements of the light path design, so as to determine the distribution of the light-passing holes in the at least two light blocking layers, and form a light guide channel that meets the requirements of the light path design.
  • the target fingerprint light signal passing through a specific direction is received by the pixel unit.
  • the transmittance of each of the at least two light-shielding layers to light of a specific wavelength band is less than a preset threshold (such as 20%) to avoid corresponding light by.
  • the light-transmitting holes may be cylindrical through-holes, or through-holes of other shapes, such as polygonal through-holes.
  • the aperture of the light-transmitting aperture may be greater than a predetermined value, for example, the aperture of the light-transmitting aperture is greater than 100 nm, so as to transmit the required light for imaging.
  • the aperture of the light-passing hole should also be smaller than a predetermined value to ensure that the light-blocking layer can block unwanted light.
  • the aperture of the light-passing hole may be smaller than the diameter of the microlens.
  • the light-transmitting small holes in the at least two light blocking layers may also include large-aperture openings that are equivalently synthesized by a plurality of small-aperture openings.
  • a plurality of small-aperture openings in the top light-blocking layer of the at least two light-blocking layers for transmitting optical signals converged by the same microlens can be combined into one large-aperture opening.
  • each of the at least two light-blocking layers may be a metal layer, and correspondingly, the light-passing holes provided in the light-blocking layer may be through holes formed in the metal layer.
  • the light-blocking layer in the at least two light-blocking layers may also be a black polymer light-absorbing material. For example, for an optical signal greater than a predetermined angle, the at least two light-blocking layers have a visible light waveband transmittance of less than 2%.
  • the parameter settings of the light-passing holes in the light-blocking layer should be as far as possible to maximize the transmission of the light signal required for imaging to the pixel unit, and the unneeded light is blocked as much as possible.
  • the parameters of the light-passing hole can be set to maximize the transmission of the optical signal obliquely incident at a specific angle (for example, 35 degrees) to the corresponding pixel unit, while maximizing the blocking of other optical signals.
  • the aforementioned fingerprint identification unit 301 may further include a transparent medium layer.
  • the lens medium layer is used to connect the circular microlens 310, at least two light blocking layers, and M pixel units.
  • the transparent medium layer can transmit optical signals in the target wavelength band (that is, optical signals in the wavelength band required for fingerprint identification).
  • the transparent dielectric layer can be oxide or nitride.
  • the transparent medium layer may include multiple layers to implement functions such as protection, transition, and buffering respectively.
  • a transition layer can be provided between the inorganic layer and the organic layer to achieve a tight connection;
  • a protective layer can be provided on the easily oxidized layer to achieve protection.
  • the aforementioned fingerprint identification unit 301 may further include an optical filter layer.
  • the optical filter layer is arranged in the optical path between the circular microlens 310 and the plane where the M pixel units are located or above the circular microlens 310, and the optical filter layer is used to filter non-target wavelength optical signals, To transmit the light signal of the target band.
  • the transmittance of the optical filter layer to light in the target wavelength band may be greater than or equal to a preset threshold, and the cut-off rate of light in the non-target wavelength range may be greater than or equal to the preset threshold.
  • the preset threshold may be 80%.
  • the optical filter layer may be an independently formed optical filter layer.
  • the optical filter layer may be an optical filter layer formed by using blue crystal or blue glass as a carrier.
  • the optical filter layer may be a coating formed on the surface of any layer in the optical path between the circular microlens 310 and the plane where the M pixel units are located.
  • a coating film may be formed on the surface of the pixel unit, the surface of any one of the transparent medium layers, or the surface of the microlens to form an optical filter layer.
  • the optical filter layer is arranged on the bottom light-blocking layer of the at least two light-blocking layers and the M pixel units. Between planes.
  • the optical filter layer is disposed between the bottom light blocking layer and the light blocking layer above it.
  • the optical filter layer may be grown on the surface of the sensor chip where the M pixel units are located, and integrated in the sensor chip.
  • a physical vapor deposition (Physical Vapor Deposition, PVD) process can be used to coat M pixel units to form an optical filter layer, for example, by atomic layer deposition, sputtering coating, electron beam evaporation coating, ion beam coating, etc.
  • the method is to prepare a multi-layer filter material film above the pixel unit.
  • the optical filter layer includes a multilayer oxide film, wherein the multilayer oxide film includes a silicon oxide film and a titanium oxide film, and the silicon oxide film and the titanium oxide film The optical filter layer is alternately grown in sequence; or the multilayer oxide film includes a silicon oxide film and a niobium oxide film, and the silicon oxide film and the niobium oxide film are alternately grown in sequence to form the optical filter layer.
  • the thickness of the optical filter layer is between 1 ⁇ m and 10 ⁇ m.
  • the optical filter layer is used to pass optical signals in the wavelength range of 400 nm to 650 nm.
  • the wavelength range of the above-mentioned target wavelength range includes 400 nm to 650 nm.
  • the N fingerprint recognition units 301 in the fingerprint recognition device 300 of the present application are not independent unit structures in structure.
  • the fingerprint recognition device 300 is not formed by splicing N fingerprint recognition units 301, but After forming the structure of the fingerprint identification device 300, in order to facilitate understanding, the fingerprint identification device 300 is divided into a plurality of fingerprint identification units 301 arranged periodically.
  • FIG. 5a shows a schematic three-dimensional structural diagram of the fingerprint identification unit 301 described above.
  • FIG. 5b is a top view of the fingerprint identification unit 301.
  • FIG. 5c is a top view of the fingerprint identification device formed by the fingerprint identification unit 301.
  • the fingerprint identification unit 301 includes:
  • Two light-blocking layers are arranged under the circular microlens 310, and each of the two light-blocking layers is provided with light-passing holes to form two light guide channels in different directions;
  • Two pixel units (a first pixel unit 331 and a second pixel unit 332) are arranged under the two light blocking layers, and the two pixel units are distributed at the bottom of the two light guide channels.
  • the two pixel units in the fingerprint identification unit 301 may be rectangular, and the two rectangular pixel units correspond to the circular microlens 310 and are arranged on the circular microlens 310.
  • the two rectangular pixel units correspond to the circular microlens 310 and are arranged on the circular microlens 310.
  • FIG. 6a shows another schematic three-dimensional structural diagram of the fingerprint identification unit 301 described above.
  • FIG. 6b is a top view of the fingerprint identification unit 301.
  • FIG. 6c is a top view of the fingerprint identification device formed by the fingerprint identification unit 301.
  • FIG. 6a shows another schematic three-dimensional structural diagram of the fingerprint identification unit 301 described above.
  • FIG. 6b is a top view of the fingerprint identification unit 301.
  • FIG. 6c is a top view of the fingerprint identification device formed by the fingerprint identification unit 301.
  • FIG. 6a shows another schematic three-dimensional structural diagram of the fingerprint identification unit 301 described above.
  • FIG. 6b is a top view of the fingerprint identification unit 301.
  • FIG. 6c is a top view of the fingerprint identification device formed by the fingerprint identification unit 301.
  • the fingerprint identification unit 301 includes:
  • each of the two light-shielding layers is provided with light-passing holes to form 3 light guide channels in different directions;
  • Three pixel units (the first pixel unit 331, the second pixel unit 332, and the third pixel unit 333) are arranged under the two light blocking layers, and the three pixel units are distributed at the bottom of the above three light guide channels.
  • FIG. 7a shows another schematic three-dimensional structural diagram of the fingerprint identification unit 301 described above.
  • FIG. 7b is a top view of the fingerprint identification unit 301.
  • FIG. 7c is a top view of a plurality of fingerprint identification units 301 arranged closely in a fingerprint identification device.
  • the fingerprint identification unit 301 includes:
  • each of the two light-blocking layers is provided with light-passing holes to form 4 light guide channels in different directions;
  • the 4 pixel units (the first pixel unit 331, the second pixel unit 332, the third pixel unit 333, and the fourth pixel unit 334) are arranged under the two light blocking layers, and the 4 pixel units are distributed in the above 4 The bottom of the light guide channel.
  • the diameter of the circular microlens 310 is not greater than the arrangement period of four pixel units.
  • the area where the four pixel units are located is an A ⁇ B quadrilateral area, where A ⁇ B, and A and B are positive integers, the diameter of the microlens 310 is less than or equal to A.
  • the four pixel units in the fingerprint detection unit 301 may be quadrilateral pixels, for example, square pixels with the same shape and size.
  • the upper surface of the circular microlens is spherical or aspheric, and the diameter of the circular microlens 310 is not greater than the arrangement period of M pixel units.
  • the diameter of the circular microlens 310 is less than or equal to A.
  • the M pixel units arranged under the circular microlens 310 may also have special-shaped patterns, so that the pixel array in the fingerprint identification device 300 has higher symmetry, higher sampling efficiency, and comparable Equidistant adjacent pixels, better angular resolution, less aliasing effects.
  • the two light-blocking layers include a first light-blocking layer 321 and a second light-blocking layer 322.
  • the first light blocking layer 321 is formed at any position between the circular microlens 310 and the plane where the M pixel units are located, which is not limited in the embodiment of the present application.
  • the second light blocking layer 322 is not shown in FIGS. 5a to 7a, and may be formed on the surface of the M pixel units, and specifically may be a metal layer on the surface of the M pixel units.
  • the second light blocking layer 322 can also be formed at any position between the circular microlens 310 and the plane where the M pixel units are located, for example, between the first light blocking layer 321 and the plane where the M pixel units are located.
  • the embodiments of the present application also do not specifically limit this.
  • a first light-passing hole 3211 is formed on the first light-blocking layer 321, and N light-passing holes are formed on the second light-blocking layer 322, for example, as shown in FIG.
  • two light-passing holes are formed on the second light blocking layer 332, which are the second light-passing hole 3221 and the third light-passing hole 3222, respectively.
  • the second light-passing hole 3221 and the first light-passing hole 3211 form a first light guide channel for passing through the first target fingerprint light signal in the fingerprint light signal collected by the circular microlens 310, which is located The first pixel unit 331 at the bottom of the first light guide channel is used for detecting fingerprint information.
  • the third light-passing hole 3222 and the first light-passing hole 3211 form a second light guide channel for passing the second target fingerprint light signal, which is located at the second pixel unit 332 at the bottom of the second light guide channel. After receiving, the first target fingerprint optical signal and the second target fingerprint optical signal are used to detect fingerprint information.
  • the first light-passing aperture 3211, the second light-passing aperture 3321, and the third light-passing aperture 3222 can be located at any position below the circular microlens 310, and are intended to form any two different directions.
  • the first pixel unit 331 and the second pixel unit 332 corresponding to the circular microlens 310 can also be located at any position below the circular microlens 310, and are intended to receive two different directions of light guide channels passing through two different directions. Fingerprint light signal.
  • the second light blocking layer 332 is formed with three light passing holes, and the three light passing holes are respectively common with the light passing holes on the first light blocking layer 331. 3 light guide channels in different directions with 3 pixel units are formed.
  • the second light blocking layer 332 is formed with 4 light passing holes, and the 4 light passing holes are respectively common with the light passing holes on the first light blocking layer 331. 4 light guide channels in different directions with 4 pixel units are formed.
  • a light guide channel is constructed by opening small holes on the light blocking layer between the M pixel units and the circular microlens 310 , To pass fingerprint light signals in different directions, so that the photosensitive areas in the M pixel units receive fingerprint light signals in different directions.
  • the fingerprint identification unit 301 includes 2 to 4 pixel units as an example.
  • the fingerprint identification device is exemplified. It should be understood that the fingerprint identification unit may also include 4 or more pixel units of any number. The number of pixel units in each fingerprint recognition unit is not specifically limited.
  • one circular microlens corresponds to M pixel units, and the M pixel units respectively receive fingerprint light signals converged by the circular microlens and passed through M light guide channels in M directions. Fingerprint light signals in M directions are received by M pixel units respectively.
  • one microlens corresponding to one pixel unit such as the fingerprint identification device in Figure 2 and Figure 3
  • it can increase the amount of light entering the fingerprint identification device, reduce the exposure time, and increase the field of view of the fingerprint identification device .
  • the angle of the fingerprint light signal received by the pixel unit is determined by the relative positional relationship between the pixel unit and the microlens. The farther the center of the lens, the larger the angle of the fingerprint light signal received by the pixel unit. Therefore, by flexibly setting the position of the pixel unit, the pixel unit can receive fingerprint light signals at a large angle, which greatly improves the recognition problem of dry fingers, and can reduce the thickness of the optical path in the fingerprint recognition unit, thereby reducing the fingerprint recognition device Thickness, reduce process cost.
  • the plurality of circular microlenses in the fingerprint identification device are arranged in close-packed manner, which can increase the duty ratio of the plurality of circular microlenses , Increase the amount of light entering the fingerprint identification device, and further improve the quality of fingerprint images and fingerprint identification performance.
  • using the technical solutions of the embodiments of the present application can improve the identification problem of dry fingers, reduce the thickness of the fingerprint identification device, and reduce the process cost. At the same time, it can increase the light input of the fingerprint identification device, reduce the exposure time, and improve the optical resolution. Rate and optical field of view to further improve the quality of fingerprint images and fingerprint recognition performance.
  • each fingerprint recognition unit includes M pixel units, then in the fingerprint recognition device, a total of N ⁇ M pixel units are included, and the N ⁇ M pixel units are used to receive different M fingerprint light signals in one direction to form M fingerprint images, and N pixel units in the N fingerprint identification units are used to receive fingerprint light signals in one direction to form one fingerprint image in the M fingerprint images, where, N pixel units belong to N fingerprint identification units respectively.
  • a fingerprint recognition unit includes two pixel units, that is, the above-mentioned first pixel unit and the second pixel unit
  • the N first pixel units of the N fingerprint recognition units are used to receive the fingerprint light signal in the first direction.
  • the N second pixel units among the N fingerprint identification units are used to receive the fingerprint light signals in the second direction, and are used to form the second fingerprint image.
  • the fingerprint recognition device receives the fingerprint light signals in the two directions. They are used to form two fingerprint images respectively.
  • FIGS. 8a and 8b show schematic diagrams of the arrangement of multiple first pixel units and multiple second pixel units in two types of multiple fingerprint recognition units 301.
  • the number "1" represents the first pixel unit
  • the number "2" represents the second pixel unit.
  • the first pixel unit and the second pixel unit in a fingerprint recognition unit are a pixel unit group, and multiple pixel unit groups in multiple fingerprint recognition units are arranged staggered, and a pixel array formed by multiple pixel unit groups An array of pixels that is not arranged in a square array.
  • the multiple pixel units in the multiple fingerprint identification units are arranged in a square array, but a second pixel unit is interspersed between two adjacent first pixel units, and two adjacent second pixel units A first pixel unit is interspersed therebetween, and a plurality of first pixel units and a plurality of second pixel units are alternately arranged.
  • the arrangement of the multiple first pixel units is the same as the arrangement of the corresponding round microlenses, and they are all arranged in a close-packed manner.
  • the first pixel unit is adjacent to the six first pixel units, and the line connecting the centers of the six first pixel units is a regular hexagon.
  • the arrangement of the multiple second pixel units is the same as the arrangement of the corresponding round microlenses. They are all arranged in a close-packed manner.
  • One second pixel unit is adjacent to six second pixel units, and The line connecting the centers of the six second pixel units is a regular hexagon.
  • FIG. 9 shows multiple first pixel units, multiple second pixel units, multiple third pixel units, and multiple first pixel units in multiple fingerprint recognition units 301.
  • the number "1" represents the first pixel unit
  • the number "2” represents the second pixel unit
  • the number "3” represents the third pixel unit
  • the number "4" represents the fourth pixel unit.
  • the plurality of pixel units in the plurality of fingerprint identification units are arranged in a square array, between the plurality of first pixel units, between the plurality of second pixel units, between the plurality of third pixel units, and The plurality of fourth pixel units are not adjacent to each other.
  • the arrangement of the multiple first pixel units, the multiple second pixel units, the multiple third pixel units, and the multiple fourth pixel units is the same as the arrangement of the corresponding multiple circular microlenses.
  • the method is the same, all are arranged in close-packed manner.
  • the data structure of the pixel values of the N-pixel units is a close-packed data structure, which is different from the fingerprint that needs to be formed.
  • the pixel values of the N pixel units need to be processed to convert the close-packed data structure into a square array data structure to form a normal fingerprint image.
  • the fingerprint identification device 300 further includes a processing unit, and the processing unit may be a processor, and the processor may be a processor in the fingerprint identification device 300, such as a microcontroller unit (Microcontroller Unit, MCU) and so on.
  • the processor may also be a processor in an electronic device where the fingerprint identification device 300 is located, such as a main control chip in a mobile phone, etc., which is not limited in the embodiment of the present application.
  • the processor is used to perform interpolation processing on the pixel values of the N pixel units receiving the same direction, convert the close-packed data structure into a square-array data structure, and obtain a fingerprint image with a square-array pixel value.
  • the first pixel unit 331 in a fingerprint recognition unit 301 is taken as an example.
  • the N fingerprint recognition units include N first pixel units 331, and the fingerprint light signals received by the N first pixel units 331 are used to form a Fingerprint image.
  • FIG. 10 shows a data structure of the original pixel values of a plurality of first pixel units 331.
  • the structure of the first pixel unit 331 in FIG. 10 may be the same as the structure of the first pixel unit 331 in FIG. 8a. the same.
  • the letter "X" represents the original pixel value output by the first pixel unit.
  • the data structure arranged in a square array in FIG. 11 can be formed.
  • the letter y in FIG. 11 represents the interpolated pixel formed after the interpolation processing.
  • the W adjacent original pixel values in FIG. 10 can be averaged and inserted between the W original pixel values as an interpolated pixel, where W is a positive integer greater than 1.
  • the interpolated pixel y 2 in FIG. 11 can be obtained by averaging the original pixels x 1 and x 6 , or can be obtained by averaging the original pixels x 3 and x 4.
  • Each interpolated pixel can be obtained by averaging its upper and lower original pixel values or by averaging its left and right original pixel values.
  • the average value of the two adjacent original pixel values is inserted.
  • the average value of the two adjacent original pixel values is inserted.
  • the interpolated pixel y 2 in FIG. 11 can be averaged from the original pixels x 1 , x 3 , x 4 and x 6.
  • each interpolated pixel can be obtained from the original pixels x 1, x 3, x 4 and x 6.
  • the four original pixel values of the top, bottom, left, and right are averaged.
  • the average value of the four adjacent original pixel values can be inserted into the center of the four original pixel values.
  • FIG. 12 shows another data structure of the original pixel values of multiple first pixel units 331, and the first pixel unit 331 in FIG. 12 may be the same as the first pixel unit 331 in FIG. 8b or FIG.
  • the structure of the unit 331 is the same.
  • the letter "x" represents the original pixel value output by the first pixel unit.
  • the square array data structure in FIG. 13 can be formed.
  • the letter y in FIG. 13 represents the interpolated pixel formed after the interpolation processing.
  • the W adjacent original pixel values in FIG. 12 can be averaged and inserted as an interpolation pixel between the W original pixel values, where W is a positive integer greater than 1.
  • the interpolation pixel y 3 in FIG. 13 can be obtained by averaging the original pixels x 2 and x 3 , or it can also be obtained by averaging the original pixels x 1 and x 4 , the same .
  • Each interpolated pixel can be obtained by averaging its upper and lower original pixel values or by averaging its left and right original pixel values.
  • the average value of the two adjacent original pixel values is inserted, or the original pixel value of each row Between two adjacent original pixel values, the average value of the two adjacent original pixel values is inserted.
  • the interpolated pixel y 3 in Fig. 13 can be averaged from the original pixels x 1 , x 2 , x 3 and x 4.
  • each interpolated pixel can be obtained from the original pixels x 1, x 2, x 3 and x 4.
  • the four original pixel values of the top, bottom, left, and right are averaged.
  • the average value of the four adjacent original pixel values can be inserted into the center of the four pixel values.
  • W can also be other positive integers greater than 1.
  • W can also be equal to 3.
  • the average value of x 1 , x 3 and x 4 in Fig. 10 can also be used as One interpolation pixel is inserted between x 3 and x 4 .
  • the average value of x 1 , x 2 and x 3 in FIG. 12 can also be inserted between x 2 and x 3 as an interpolation pixel.
  • interpolation methods can also be used to process the original pixel values of multiple first pixel units.
  • the median value of multiple adjacent original pixel values or from multiple One original pixel value among the original pixels is selected as the interpolation pixel, which aims to process the closely arranged data structure into a data structure arranged in a square array.
  • the embodiment of the present application does not specifically limit the specific interpolation method.
  • the pixel value interpolation process of the multiple first pixel units is explained. It should be understood that the fingerprint identification device receives multiple target fingerprint light signals in the same direction.
  • the pixel interpolation process of the pixel unit for example, multiple second pixel units, multiple third pixel units, or multiple fourth pixel units, reference may be made to the pixel interpolation process of the multiple first pixel units described above, which will not be repeated here.
  • the pixel values of the N pixel units that receive the fingerprint light signal in one direction can form a fingerprint image with a square arrangement of pixel values through the above-mentioned interpolation process, then the M groups of N pixel units in the fingerprint identification device pass The above interpolation process can form M fingerprint images with square pixel values.
  • a plurality of circular microlenses in the microlens array 210 are arranged in a square array.
  • the fingerprint identification device 200 has the same spatial sampling rate in the X direction and the Y direction, and they are all a circle.
  • the N circular microlenses in the fingerprint identification device 300 are arranged in close rows, and the fingerprint identification device 300 has different spatial sampling rates in the X direction and the Y direction.
  • the spatial sampling rate of the fingerprint identification device 300 is the distance D between the centers of two adjacent circular microlenses. If the radius of the circular microlens is R, the fingerprint identification device is at The spatial sampling rate in the X direction is 2R. In the Y direction, the spatial sampling rate of the fingerprint identification device is The spatial sampling rate of the fingerprint identification device 300 in the X direction is greater than the spatial sampling rate in the Y direction.
  • the spatial sampling rate of the fingerprint identification device 300 is less than 75 ⁇ m, that is, the distance between the centers of two adjacent circular microlenses is less than 75 ⁇ m.
  • the radius of the circular microlenses is less than 37.5 ⁇ m.
  • the spatial sampling rate in the X direction of the M fingerprint images in the square arrangement of pixel values formed by the above-mentioned interpolation process is R
  • the spatial sampling rate in the Y direction is
  • the M fingerprint images are not real fingerprint images, but deformed fingerprint images. It is necessary to perform further optimization processing on the M fingerprint images and adjust their aspect ratios to obtain real M optimized fingerprint images.
  • the aspect ratio of the fingerprint image can be adjusted to form a true optimized fingerprint image.
  • the fingerprint image formed after the above interpolation is a fingerprint image with a size of A ⁇ B pixels
  • A is the number of pixels in the X direction
  • B is the number of pixels in the Y direction.
  • the real fingerprint image obtained is an optimized fingerprint image with a pixel size of A' ⁇ B', A'is the number of pixels in the X direction, and B'is the number of pixels in the Y direction.
  • B B', that is, the fingerprint image with the size of A ⁇ B pixels is performed in the X direction
  • Up-sampling by a factor of two which increases the number of pixels in the X-direction of the optimized fingerprint image
  • the number of pixels in the Y direction remains unchanged.
  • A A', That is, the fingerprint image of A ⁇ B pixel size is performed in the Y direction Times of downsampling, so that the number of pixels in the Y direction of the optimized fingerprint image is reduced to the previous The number of pixels in the X direction does not change.
  • one or more of the M optimized fingerprint images can be used for fingerprint identification alone.
  • the processing unit may reconstruct multiple optimized fingerprint images among the M optimized fingerprint images to form a target reconstructed image, and the target reconstructed image is used for fingerprint recognition.
  • the reconstructed image is an image formed by superimposing multiple optimized fingerprint images, and the number of pixels of the reconstructed image is the sum of the pixel numbers of the multiple optimized fingerprint images.
  • the processing unit superimposes two optimized fingerprint images to form a reconstructed image.
  • the processing unit can adjust the moving distance of the two optimized fingerprint images through algorithms according to the quality parameters of the reconstructed image to form The first target reconstructs the image.
  • the above-mentioned quality parameters of the reconstructed image include, but are not limited to: the contrast of the reconstructed image, the clarity of the reconstructed image, the signal-to-noise ratio of the reconstructed image, or the similarity between the reconstructed image and two images.
  • adjusting the moving distance of the two images may be adjusting the number of pixels of the moving images of the two optimized fingerprint images.
  • the moving distance of the two optimized fingerprint images is the distance of N image pixels
  • the N may be adjusted according to the quality parameter of the reconstructed image to form the first target reconstructed image.
  • the thickness of the display screen is constant, and the relative position of the display screen and the fingerprint recognition device is basically unchanged, it is possible to test the number of image pixels that need to be moved to reconstruct the two images into the target reconstructed image, and the image pixels The number of points is determined as the moving image parameter, and the moving image parameter is stored in the storage unit. Furthermore, in the subsequent fingerprint collection process, a clear image can be reconstructed based on the moving image parameters.
  • the installation distance between the fingerprint identification device and the display screen changes when a strong impact is encountered, or the installation distance between the fingerprint identification device and the display screen during mass production.
  • the pixel distance of the two optimized fingerprint images will change.
  • the distance between the two optimized fingerprint images will be automatically calibrated when the installation distance changes, so as to ensure the reconstruction of the image.
  • the sharpness, signal-to-noise ratio and contrast ratio ensure the fingerprint recognition effect of the fingerprint recognition device and improve the user experience.
  • the distance of the image pixels to be moved for each optimized fingerprint image can be re-determined. It can also be determined that the position of the fingerprint module relative to the display screen has shifted by evaluating that the quality of the image is lower than the preset threshold or the value measured by the accelerometer exceeds the preset threshold.
  • the two optimized fingerprint images are the first optimized fingerprint image and the second optimized fingerprint image
  • the processing unit obtains the first area in the first optimized fingerprint image.
  • the first area may be the first optimized fingerprint image.
  • One is to optimize the central area of the fingerprint image or other arbitrary areas. The embodiment of the present application does not limit the location and size of the area.
  • the processing unit determines the second area closest to the first area in the second optimized fingerprint image according to the pixel value of the first area.
  • feature extraction can be performed on the pixel values in the first region, for example, image features such as high-frequency features are extracted, and the second optimized fingerprint image is searched to obtain the first region that is closest to the feature of the first region. Two areas.
  • the first area in the first optimized fingerprint image and the second area in the second optimized fingerprint image may be image areas that are imaged based on the same finger area.
  • the images are the same or similar in height, and the shape and size of the first area and the second area may be the same.
  • the coordinates of the first area may be the coordinates of the center point of the first area
  • the coordinates of the second area may also be the coordinates of the center point of the second area.
  • the coordinates of the first area and the coordinates of the second area may also be the coordinates of the upper left corner, etc., which are not limited in the embodiment of the present application.
  • the first optimized fingerprint image and the second optimized fingerprint image are pixel shifted to obtain the first target reconstructed image.
  • the first optimized image Move the corresponding ⁇ X, ⁇ Y pixels, and then intersect the pixels of the second optimized image and the first optimized image to obtain the first target reconstructed image.
  • the first area and the second area are fused into one target area, and the number of pixels in the target area is the sum of the number of pixels in the first area and the second area.
  • the number of pixels of the first target reconstructed image is the sum of the number of pixels of the first optimized fingerprint image and the second optimized fingerprint image.
  • two optimized fingerprint images can be obtained to form the first target reconstructed image. If the number of pixels in the fingerprint identification unit is greater than 2, when the fingerprint identification device forms more than two optimized fingerprint images, other
  • the optimized fingerprint image can also be reconstructed according to the above-mentioned method to form multiple target fingerprint reconstruction images reconstructed from the optimized fingerprint images, and the target fingerprint reconstruction image is used for fingerprint identification.
  • the 4 optimized fingerprint images can be divided into 2 groups, and the two optimized fingerprint images in each group can be reproduced as described above.
  • a first target reconstructed image is constructed, and then two first target reconstructed images are reconstructed again to obtain the final target reconstructed image.
  • the use of reconstructed images for fingerprint identification enables the fingerprint identification device to have a large field of view, which can further improve the performance of the fingerprint identification device.
  • the basic structure of the fingerprint identification device 300 and the process of fingerprint image processing in the embodiment of the present application have been described in detail with reference to FIGS. 4 to 13.
  • the N fingerprints in the fingerprint identification device 300 will be compared with FIGS. 14 to 21.
  • the structure of each fingerprint recognition unit 301 in the recognition unit 301 will be described in detail.
  • the target fingerprint light signals in the M directions received by the M pixel units in the fingerprint identification unit 301 are all light signals inclined with respect to the display screen, or one target fingerprint light signal in the target fingerprint light signals in the M directions is The optical signal inclined perpendicular to the display screen, and the other M-1 target fingerprint optical signals are optical signals inclined to the display screen.
  • the directions of the M light guide channels in different directions formed in at least two light blocking layers are all inclined directions relative to the display screen.
  • the direction of one light guide channel among the M light guide channels in different directions is a direction perpendicular to the display screen, and the direction of the other M-1 light guide channels is a direction inclined with respect to the display screen.
  • the angle of the target fingerprint light signal in the M directions may be between 0° and 60°.
  • the angle of the fingerprint light signal received by the circular microlens 310 may also be between 0° and 60°.
  • the angle between the M light guide channels in different directions formed in the at least two light-blocking layers and the direction perpendicular to the display screen can also be between 0° and 60°, or in other words, the angles formed in the at least two light-blocking layers
  • the angle between the M light guide channels in different directions and the display screen can be between 30° and 90°. If the display screen is arranged parallel to the plane where the M pixel units in the fingerprint recognition unit 301 are located, at least two light-blocking layers
  • the included angles between the M light guide channels in different directions formed in, and the plane where the M pixel units are located may be between 30° and 90°.
  • the included angles between the foregoing M light guide channels in different directions and the display screen may be the same.
  • the bottom light-blocking layer of the at least two light-blocking layers is provided with M light-passing holes corresponding to the M pixel units, respectively.
  • the fingerprint identification unit 301 including two pixel units as an example, the structure of the fingerprint identification unit 301 will be described in detail.
  • Fig. 14 shows a schematic top view of the fingerprint identification unit in Fig. 5.
  • Fig. 15 is a schematic cross-sectional view of the fingerprint recognition unit in Fig. 14 along the A-A' direction.
  • the fingerprint identification unit includes two light-blocking layers.
  • the top light-blocking layer of the two-layer light-blocking layer is provided with a first light-passing hole 3211.
  • the bottom light-blocking layer is provided with a second light-passing hole 3221 corresponding to the first pixel unit 331 and a third light-passing hole 3222 corresponding to the second pixel unit 332.
  • the direction of the light guide channel in the multi-layer light-blocking layer may be the center of the uppermost light-passing hole in the light guide channel The direction of the connection with the center of the lowermost light-passing hole.
  • the direction of the light guide channel is a direction close to the direction of the center line, for example, the direction of the light guide channel and the direction of the center line are within ⁇ 5°.
  • the direction of the first light guide channel corresponding to the first pixel unit 331 is the connecting direction of the first light-passing hole 3211 and the second light-passing hole 3221 or a direction close to the connecting direction.
  • the direction of the second light guide channel corresponding to the second pixel unit 331 is the connecting direction of the first light-passing hole 3211 and the third light-passing hole 3222 or a direction close to the connecting direction.
  • the first target fingerprint light signal 311 is received by the first photosensitive area 3311 in the first pixel unit through the first light guide channel formed by the first light-passing hole 3211 and the second light-passing hole 3221
  • the second target fingerprint light signal 312 is received by the second photosensitive area 3321 in the second pixel unit through the second light guide channel formed by the first light-passing hole 3211 and the third light-passing hole 3222.
  • the distance from the center of the first photosensitive area 3311 to the center of the microlens 310 and the distance from the center of the second photosensitive area 3321 to the center of the microlens 310 are equal.
  • the first target fingerprint optical signal 311 received by the first photosensitive area 3311 and the second target fingerprint optical signal 312 received by the second photosensitive area 3321 have the same angle with the display screen, or in other words, the first target fingerprint optical signal 311 received by the first photosensitive area 3311 and the second target fingerprint optical signal 312 received by the second photosensitive area 3321.
  • the angle between the first light guide channel corresponding to a photosensitive area 3311 and the display screen is equal to the angle between the second light guide channel corresponding to the second photosensitive area 3321 and the display screen.
  • the distance from the center of the first photosensitive area 3311 to the center of the microlens 310 and the distance from the center of the second photosensitive area 3321 to the center of the microlens 310 may not be equal.
  • the first target fingerprint light signal 311 received by the first photosensitive area 3311 and the second target fingerprint light signal 312 received by the second photosensitive area 3321 have different angles with the display screen, or in other words, the first photosensitive area
  • the angle between the first light guide channel corresponding to 3311 and the display screen and the angle between the second light guide channel corresponding to the second photosensitive area 3321 and the display screen are not equal.
  • the at least two light-blocking layers may also be three light-blocking layers.
  • another light-blocking layer is provided in the two light-blocking layers in the above-mentioned application embodiment, and the light-blocking layer is also provided
  • the light passing holes corresponding to the first pixel unit 331 and the second pixel unit 332 form two light guide channels corresponding to the two pixel units.
  • the light blocking layer between the bottom light blocking layer and the top light blocking layer is the middle light blocking layer.
  • the bottom light blocking layer The connection direction of the light passing holes of the light layer and the top light blocking layer is the direction of the light guide channel, and the center of the light passing holes in the middle light blocking layer can be respectively located on the connection line of the two light guiding channels.
  • the bottom light-shielding layer in the at least two light-shielding layers is a metal wiring layer on the surface of the two pixel units.
  • the metal wiring layers of the first pixel unit 331 and the second pixel unit 332 are arranged at the back focal plane position of the microlens 310, and the metal wiring layer is the bottom light-blocking layer of at least two light-blocking layers, and is located in the first pixel
  • a second light-passing hole 3221 and a third light-passing hole 3222 are formed above the photosensitive regions of the unit 331 and the second pixel unit 332, respectively.
  • the bottom light-shielding layer of at least two light-shielding layers is formed on the metal wiring layer of the fingerprint sensor chip, and a corresponding light-passing hole is formed above the photosensitive area of each pixel unit.
  • the metal wiring layer of the fingerprint sensor chip can be reused for the optical path layer between the microlens and the pixel unit.
  • the top light-blocking layer of the at least two light-blocking layers is provided with at least one light-passing hole corresponding to the first pixel unit 331 and the second pixel unit 332.
  • the first pixel unit 331 and the second pixel unit 332 may be respectively provided with a light-passing hole in the top light blocking layer.
  • the top light blocking layer may also be the first pixel unit 331 and the second pixel unit 332.
  • a light-passing hole is provided together, such as the aforementioned first light-passing hole 3211.
  • the first light guide channel corresponding to the first pixel unit 321 and the second light guide channel corresponding to the second pixel unit 322 are in at least two layers. The light-transmitting small holes in the top light-blocking layer of the light-blocking layer overlap.
  • the apertures of the light-passing holes in the first light guide channel and the second light-guiding channel are sequentially reduced from top to bottom, for example, the apertures of the second light-passing aperture 3221 and the third light-passing aperture 3222 Both are smaller than the aperture of the first light-passing hole 3211.
  • the aperture of the light-passing hole in the upper light-shielding layer is set to be larger than the aperture of the light-passing hole in the lower light-shielding layer, thereby. It is possible to make at least two light blocking layers to guide more (a certain angle range) of light signals to the corresponding pixel units.
  • Fig. 16 shows a schematic top view of another fingerprint recognition unit 301
  • Fig. 17 shows a schematic cross-sectional view of the fingerprint recognition unit 301 in Fig. 12 along the A-A' direction.
  • the fingerprint identification unit 301 includes three light-blocking layers.
  • the top light blocking layer is provided with the aforementioned first light-passing aperture 3211
  • the bottom light-shielding layer is provided with the aforementioned second light-passing aperture 3221 and the aforementioned third light-passing aperture 3222.
  • a fourth light-passing hole 3231 and a fifth light-passing hole 3232 are provided in the newly added light blocking layer of the intermediate layer.
  • the first light-passing hole 3221, the fourth light-passing hole 3231, and the second light-passing hole 3221 form the first light guide channel corresponding to the first photosensitive area 3311 unit, and the centers of the three light-passing holes can be Located on the same line.
  • the first light-passing aperture 3221, the fifth light-passing aperture 3232, and the third light-passing aperture 3222 form a second light guide channel corresponding to the second photosensitive area 3321.
  • the centers of the three light-passing apertures can also be Located on the same line.
  • the aperture of the first aperture 3221 is larger than the aperture of the fourth aperture 3231 and the fifth aperture 3232, and the fourth aperture 3231 and the fifth aperture 3232
  • the aperture of the light-passing hole 3232 is larger than the apertures of the second light-passing hole 3221 and the third light-passing hole 3222.
  • the fingerprint identification unit 301 may also include more light-blocking layers.
  • two light-blocking layers are used as a schematic illustration.
  • Relevant instructions will not be repeated here.
  • the area where the first pixel unit 331 and the second pixel unit 332 are located (for ease of description, in this embodiment of the present application, the area where the first pixel unit 331 and the second pixel unit 332 are located is referred to as The pixel area 330) may be located directly below the circular microlens 310, and the center of the pixel area 330 and the center of the microlens 310 coincide in the vertical direction.
  • the first pixel unit 331 and the second pixel unit 332 both receive the target fingerprint light signal in the oblique direction, that is, the first light guide channel corresponding to the first pixel unit 331 and the second light guide channel corresponding to the second pixel unit 332
  • the directions are all inclined relative to the display.
  • the first pixel unit 331 and the second pixel unit 332 both include a photosensitive area (Active Area, AA) for receiving the first target fingerprint light signal and the second target fingerprint light signal passing through the two light guide channels respectively. Converted to the corresponding electrical signal.
  • AA Photosensitive area
  • the photosensitive area may be a quadrilateral area, for example, it may be a square area or a rectangular area.
  • the photosensitive area can be the area where the photodiode in the pixel unit is located, that is, the area in the pixel unit that receives the light signal, and other areas in the pixel unit can be used to set other circuits in the pixel unit and for the wiring arrangement between pixels .
  • the light sensitivity of the photosensitive region to blue light, green light, red light or infrared light is greater than a first predetermined threshold
  • the quantum efficiency is greater than a second predetermined threshold.
  • the first predetermined threshold may be 0.5v/lux-sec
  • the second predetermined threshold may be 40%.
  • the photosensitive area has high light sensitivity and high quantum efficiency for blue light (wavelength of 460 ⁇ 30nm), green light (wavelength of 540 ⁇ 30nm), red light or infrared light (wavelength ⁇ 610nm), In order to detect the corresponding light.
  • the first photosensitive area 3311 of the first pixel unit 331 is located below the second light-passing hole 3221, that is, at the bottom of the first light guide channel, and is used to receive the light signal of the first target fingerprint.
  • the photosensitive area 3321 is located below the third light-passing hole 3222, that is, at the bottom of the second light guide channel, and is used to receive the second target fingerprint light signal.
  • the pixel area 330 composed of the first pixel unit 331 and the second pixel unit 332 is a quadrangular pixel area.
  • the first photosensitive area 3311 and the second photosensitive area 3321 may be located on the opposite side of the pixel area 330. Corner line.
  • the projection of the first target fingerprint light signal received by the first photosensitive area 3311 and the second target fingerprint light signal received by the second photosensitive area 3321 on the plane where the pixel area 330 is located is an included angle of 180°, or In other words, the projection of the first light guide channel on the plane of the pixel area 330 and the projection of the second light guide channel on the plane of the pixel area 330 form an angle of 180°.
  • the projection angle of the first target fingerprint light signal received by the first photosensitive area 3311 and the second target fingerprint light signal received by the second photosensitive area 3321 on the plane where the pixel area 330 is located is 90°.
  • °Included angle in other words, the projection of the first light guide channel on the plane of the pixel area 330 and the projection of the second light guide channel on the plane of the pixel area 330 are at an angle of 90°.
  • the fingerprint light signals received by the two pixel units are perpendicular to each other, which facilitates the collection of fingerprint light signals perpendicular to the ridges and valleys of the fingerprint, and can improve the quality of the fingerprint light signals received by the fingerprint identification unit. Thereby improving the quality of the fingerprint image and improving the fingerprint recognition performance of the fingerprint recognition device.
  • the implementation of the projection of the first light guide channel and the second light guide channel on the plane where the pixel area 330 is at an angle of 180° or an angle of 90° is not limited to those shown in FIGS. 14, 16 and 18.
  • the fingerprint recognition unit, and other structures that realize the projection of the first light guide channel and the second light guide channel on the plane where the pixel area 330 is at an angle of 180° or an angle of 90° are also within the scope of protection of the present application.
  • the direction of the corresponding light guide channel can be adjusted by setting the pixel unit and the photosensitive area in the pixel unit to meet the requirements of the designed light path.
  • the photosensitive area in the two pixel units only occupies a small part of the area in the pixel unit, so as to meet the requirements of receiving light signals.
  • the center of the first photosensitive area 3311 may be located at the bottom of the first light guide channel, and the center of the second photosensitive area 3321 may be located at the bottom of the second light guide channel.
  • the center of the first photosensitive area 3311 is located on the line connecting the first light-passing hole 3211 and the second light-passing hole 3221, and the center of the second photosensitive area 3321 is located between the first light-passing hole 3211 and the third light-passing hole 3211. On the line of the small hole 3222.
  • the first target fingerprint light signal forms a first light spot 3301 on the first pixel unit 331 through the first light guide channel
  • the second target fingerprint light signal forms a first light spot 3301 on the second pixel unit 332 through the second light guide channel.
  • the first photosensitive area 3311 on the first pixel unit 331 may completely cover the first light spot 3301, and the second pixel unit 332
  • the second photosensitive area 3321 can completely cover the second light spot 3302 described above.
  • the first pixel unit is a quadrilateral area, the length and width of which are respectively L and W, where W ⁇ L, W and L are both positive numbers, and the length and width of the first photosensitive area in the first pixel unit All are greater than or equal to 0.1 ⁇ W.
  • the size of the second pixel unit and its second photosensitive area can also correspondingly satisfy the above conditions.
  • the first photosensitive area 3311 is a quadrilateral area and circumscribes the first spot 3301.
  • the second photosensitive area 3321 is The quadrilateral area is circumscribed to the second light spot 3302.
  • the photosensitive area in the pixel unit is small, but the fingerprint light signal after passing through the light guide channel is fully received, which meets the fingerprint imaging requirements.
  • the area of other areas in the pixel unit is larger, which gives the pixel
  • the wiring of the unit provides sufficient space, reduces the process requirements, and improves the efficiency of the process manufacturing, and other areas can be used to set other circuit structures, which can improve the signal processing capability of the pixel unit.
  • the center of the photosensitive area may not be located at the bottom of the light guide channel, but a certain offset occurs. At this time, the photosensitive area can be enlarged.
  • the area of the area is such that the photosensitive area can cover the entire area of the light spot of the fingerprint light signal on the pixel unit.
  • the first pixel unit 331 and the second pixel unit 332 are rectangular pixel units, and the first photosensitive area 3311 and the second photosensitive area 3321 are offset from the two pixel units. Center setting. Since both the first pixel unit 331 and the second pixel unit 332 receive light signals in an oblique direction, and the greater the tilt angle, the farther the photosensitive area in the pixel unit is from the center of the microlens. Therefore, in addition to being offset from the center of the pixel unit, the first photosensitive area 3311 and the second photosensitive area 3321 are also offset away from the center of the microlens, which can increase the angle of the target fingerprint light signal received by the two photosensitive areas. , Thereby reducing the thickness of the fingerprint recognition unit.
  • the first photosensitive area 3311 and the second photosensitive area 3321 may also be located at the center of the first pixel unit 331 and the second pixel unit 332.
  • the first pixel unit 331 and the second pixel unit 332 are shifted away from the center of the microlens to increase the angle of the target fingerprint light signal received by the two photosensitive areas, and reduce the thickness of the fingerprint identification unit.
  • the two photosensitive areas can be arranged at any position in the pixel unit, aiming to receive the target fingerprint light signal passing through the two channels.
  • the embodiment of the present application determines the specific positions of the two photosensitive areas in the pixel unit. Do not make any restrictions.
  • the photosensitive area in the two pixel units occupies most of the area in the pixel unit, so as to increase the dynamic range of the pixel unit.
  • FIG. 19 shows another schematic top view of the fingerprint identification unit 301.
  • the photosensitive area in the two pixel units has a relatively large area, and in addition to covering the light spot on the pixel unit, it also covers other areas.
  • the photosensitive area in the two pixel units occupies most of the area of the pixel unit.
  • the first photosensitive area 3311 in the first pixel unit 331 occupies more than 95% of the area of the first pixel unit 331
  • the second photosensitive area 3321 in the second pixel unit 332 occupies the second pixel unit More than 95% of the area in 332.
  • the photosensitive area of the pixel unit is increased, which can increase the full well capacity of the pixel unit and the dynamic range of the pixel unit (Dynamic Range), thereby improving the overall performance of the pixel unit and realizing high dynamic range imaging of the fingerprint recognition device (High Dynamic Range Imaging, HDR).
  • High Dynamic Range Imaging, HDR High Dynamic Range Imaging
  • FIGS. 14 to 19 only show a top view of part of the fingerprint recognition unit 301 when the center of the pixel area 330 and the center of the circular microlens overlap in the vertical direction, the first pixel unit and the second
  • the photosensitive areas in the two pixel units can be respectively arranged in any area in the pixel unit, so as to realize the reception of target fingerprint light signals at different angles.
  • the center of the pixel area 330 and the center of the circular microlens may not overlap in the vertical direction.
  • the first pixel unit 331 and the second pixel unit 332 are located obliquely below the circular microlens 310 in spatial position, and the photosensitive areas in the first pixel unit and the second pixel unit can also be respectively arranged in any area of the pixel unit.
  • the fingerprint recognition unit includes two pixel units as an example for detailed description. It should be understood that if the fingerprint recognition unit includes more than two pixel units, two of the pixel units and The corresponding light guide channel can refer to the above description.
  • FIG. 20 and FIG. 21 show two schematic top views of the fingerprint identification unit 301 in FIG. 7, and the fingerprint identification unit 301 includes four pixel units.
  • the area where the first pixel unit 331, the second pixel unit 332, the third pixel unit 333, and the fourth pixel unit 334 are located (for ease of description, in the following, the area where the four pixel units are located is simply referred to as pixel The area 330) may be located obliquely below the circular microlens 310, and the center of the pixel area 330 and the center of the circular microlens 310 do not overlap in the vertical direction.
  • the area where the four pixel units are located may also be located below the circular microlens 310, and the center of the pixel area 330 and the center of the circular microlens 310 overlap in the vertical direction.
  • At least three of the four pixel units receive the target fingerprint light signal in the oblique direction, in other words, the four pixel units all receive the target fingerprint light signal in the oblique direction, that is, the four light guides corresponding to the four pixel units
  • the directions of the channels are all inclined relative to the display screen.
  • three of the four pixel units receive the target fingerprint light signal in the oblique direction, and the other pixel unit receives the target fingerprint light signal in the vertical direction.
  • each of the four pixel units includes a photosensitive area for respectively receiving four target fingerprint light signals passing through the four light guide channels and converting them into corresponding electrical signals.
  • the first photosensitive area 3311 of the first pixel unit 331 is located below the second light-passing hole 3221, that is, at the bottom of the first light guide channel, and is used to receive the first target fingerprint light signal;
  • the second pixel unit 332 The photosensitive area 3321 is located below the third light-passing hole 3222, that is, at the bottom of the second light guide channel, for receiving the second target fingerprint light signal;
  • the third photosensitive area 3331 of the third pixel unit 333 is located at the fourth light-passing Below the small hole 3223, that is, at the bottom of the third light guide channel, is used to receive the third target fingerprint light signal.
  • the fourth photosensitive area 3341 of the fourth pixel unit 334 is located below the fifth light-passing hole 3224, that is, located The bottom of the fourth light guide channel is used to receive the fourth target fingerprint optical signal.
  • angles between the fingerprint light signals received by the four photosensitive areas and the display screen may be partly the same, or all the same, or all different, which is not limited in the embodiment of the present application.
  • the fingerprint identification unit also includes three light-blocking layers, or includes more light-blocking layers.
  • the fingerprint identification unit also includes three light-blocking layers, or includes more light-blocking layers.
  • more light-blocking layers please refer to the relevant description above. I won't repeat it here.
  • the photosensitive area in the four pixel units only occupies a small part of the area in the pixel unit, so as to meet the requirements of receiving light signals.
  • the center of the first photosensitive area 3311 may be located at the bottom of the first light guide channel. In other words, the center of the first photosensitive area 3311 may be located at the first light-passing aperture 3211 and the second light-passing aperture. On the 3221 line. Similarly, the center of the photosensitive area in other pixel units can also be located at the bottom of the corresponding light guide channel.
  • the first target fingerprint light signal forms a first light spot 3301 on the first pixel unit 331 through the first light guide channel
  • the second target fingerprint light signal forms a first light spot 3301 on the second pixel unit 332 through the second light guide channel.
  • Two light spots 3302 the third target fingerprint light signal forms a third light spot 3303 on the third pixel unit 333 through the third light guide channel
  • the fourth target fingerprint light signal forms a third light spot on the fourth pixel unit 334 through the fourth light guide channel
  • the first photosensitive area 3311 on the first pixel unit 331 may be The first light spot 3301 is completely covered, the second light-sensitive area 3321 on the second pixel unit 332 can completely cover the second light spot 3302, and the third light-sensitive area 3331 on the third pixel unit 333 can completely cover the third light spot 3303, In addition, the fourth photosensitive area 3331 on the fourth pixel unit 334 can completely cover the fourth light spot 3304.
  • the first pixel unit 331 may be a quadrangular area, and its length and width are respectively L and W, where W ⁇ L, W and L are both positive numbers, and in the first pixel unit 331
  • the length and width of the first photosensitive area 3311 are both greater than or equal to 0.1 ⁇ W.
  • the sizes of the other three pixel units and the photosensitive area in the four pixel units can also correspond to the above conditions.
  • the photosensitive area in the four pixel units is a quadrilateral area and circumscribes the photosensitive area.
  • the photosensitive area in the pixel unit is small, but the fingerprint light signal after passing through the light guide channel is fully received, which meets the fingerprint imaging requirements.
  • the area of other areas in the pixel unit is larger, which gives the pixel
  • the wiring of the unit provides sufficient space, reduces the process requirements, and improves the efficiency of the process manufacturing, and other areas can be used to set other circuit structures, which can improve the signal processing capability of the pixel unit.
  • the center of the photosensitive area may not be located at the bottom of the light guide channel, but a certain offset occurs. At this time, the photosensitive area can be enlarged.
  • the area of the area is such that the photosensitive area can cover the entire area of the light spot of the fingerprint light signal on the pixel unit.
  • the four pixel units are all quadrilateral pixel units with the same size.
  • the shape, size and relative position of the four pixel units can be set arbitrarily, and the shape and size of the four pixels can be the same or different.
  • the embodiment does not make any limitation on this.
  • the first pixel unit and the third pixel unit of the four pixel units are square pixels, and the second pixel unit is a rectangular pixel, or the four pixel units are all square pixels, and so on.
  • the four photosensitive regions may be offset from the center of the four pixel units. Since the four photosensitive areas can all receive light signals in the oblique direction, and the greater the tilt angle, the farther the photosensitive area in the pixel unit is from the center of the microlens. For example, as shown in FIG. 20, the third photosensitive area and the second The four photosensitive areas are farther away from the center of the microlens, while the first photosensitive area and the second photosensitive area are closer to the center of the microlens. Therefore, the third and fourth photosensitive areas receive the target fingerprint light signal at a higher angle. Large, the angle of the target fingerprint light signal received by the first photosensitive area and the second photosensitive area is smaller.
  • the four photosensitive areas are not only offset from the center of the pixel unit, but also offset away from the center of the microlens, which can increase the angle of the target fingerprint light signal received by the four photosensitive areas, thereby further reducing fingerprint recognition.
  • the thickness of the unit is not only offset from the center of the pixel unit, but also offset away from the center of the microlens, which can increase the angle of the target fingerprint light signal received by the four photosensitive areas, thereby further reducing fingerprint recognition.
  • the four photosensitive areas may also be located at the center of the four pixel units respectively.
  • the four pixel units may be directed away from the center of the microlens. Offset, increase the angle of the target fingerprint light signal received by the four photosensitive areas, and reduce the thickness of the fingerprint identification unit.
  • the four pixel units can also be arranged at any position under the circular microlens, and the four light-sensitive areas can be arranged at any position in the four pixel units, aiming to receive the signals passing through the four channels.
  • the embodiment of the present application does not make any restrictions on the positions of the four pixel units and the specific positions of the four photosensitive areas in the pixel units.
  • the first target fingerprint light signal received by the first photosensitive area 3311 and the second target fingerprint light signal received by the second photosensitive area 3321 are projected on the plane of the pixel area 330 at an angle of +90°.
  • the projection angle of the first target fingerprint light signal received by a photosensitive area 3311 and the third target fingerprint light signal received by the third photosensitive area 3331 on the plane of the pixel area 330 is -90°, and the first photosensitive area 3311 receives
  • the angle between the projection of the first target fingerprint optical signal and the fourth target fingerprint optical signal received by the fourth photosensitive area 3341 on the plane where the pixel area 330 is located is 180°.
  • the projection of the first light guide channel on the plane where the pixel area 330 is located and the projection of the second light guide channel on the plane where the pixel area 330 is located are at an angle of +90°, and the projection of the first light guide channel on the plane where the pixel area 330 is located It forms an angle of -90° with the projection of the third light guide channel on the plane where the pixel area 330 is located, and the projection of the first light guide channel on the plane where the pixel area 330 is located is the same as the projection of the fourth light guide channel on the plane where the pixel area 330 is located. 180° included angle.
  • the fingerprint light signals received by multiple groups of two pixel units in the four pixel units are perpendicular to each other, that is, the first pixel unit and the second pixel unit, the first pixel unit and the third pixel unit,
  • the fingerprint light signals received by the fourth pixel unit and the second pixel unit, and the fourth pixel unit and the third pixel unit are perpendicular to each other.
  • the quality of the fingerprint light signal received by the fingerprint identification unit can be improved, thereby improving the quality of the fingerprint image and improving the fingerprint identification performance of the fingerprint identification device.
  • the fingerprint light signal received by any two of the four pixel units is vertical, that is, the fingerprint light signal that can be collected perpendicular to the ridge and valley lines of the fingerprint, which improves the quality of the fingerprint light signal received by the fingerprint identification unit.
  • the angles of the fingerprint light signals received by the other two pixel units of the four pixel units are not limited in this embodiment of the application.
  • the distance from the center of the first photosensitive area 3311 to the center of the microlens 310, the distance from the center of the second photosensitive area 3321 to the center of the microlens 310, and the distance from the center of the third photosensitive area 3331 to the microlens 310 Any two of the distance between the center of the lens 310 and the distance between the center of the fourth photosensitive area 3341 and the center of the microlens 310 may not be equal, or the four distances may not be equal.
  • the first target fingerprint optical signal, the second The target fingerprint optical signal, the third target fingerprint optical signal, and the fourth target fingerprint optical signal are not equal to any two of the four included angles of the display screen, or the four included angles are not equal, or in other words, the first guide Any two of the four included angles between the light channel, the second light guide channel, the third light guide channel, and the fourth light guide channel and the display screen are not equal, or none of the four included angles are equal.
  • the above only exemplifies two cases where the pixel area 330 where the four pixel units in the fingerprint identification unit 301 are located is located under the circular microlens 310. It should be understood that the pixel area 300 may also be located in any area under the microlens 310. The embodiment of the application does not make any limitation on this, and the photosensitive area in the four pixel units can be located in any area of the pixel unit where it is located, and the embodiment of the application does not make any limitation on this.
  • the direction of the target fingerprint light signal received by the photosensitive area and the direction of the light guide channel corresponding to the photosensitive area also change accordingly.
  • it can also be designed according to the light path, Design the position of the pixel unit and the photosensitive area relative to the microlens in the direction of the target fingerprint light signal demand.
  • the angle of the first target fingerprint optical signal received by the first pixel unit is greater than the angle of the other three target fingerprint optical signals among the four target fingerprint optical signals.
  • Angle refers to the angle between the optical signal and the direction perpendicular to the display screen.
  • the height h of the optical path between the circular microlens 310 and the plane where the four pixel units are located is calculated according to the following formula:
  • x is the distance between the center of the first photosensitive area 3311 receiving the optical signal of the first target fingerprint and the projection point of the center of the microlens 310 on the plane where the four pixel units are located
  • ⁇ is the distance of the optical signal of the first target fingerprint. angle.
  • the height h of the optical path between the circular microlens 310 and the plane where the M pixel units are located can also be calculated according to the above formula.
  • Fig. 22 is a schematic structural diagram of an electronic device including a plurality of fingerprint recognition units.
  • the electronic device 30 may include a display screen 120, a filter 400 located below the display 120, and a fingerprint identification device 300 composed of a plurality of fingerprint identification units 301 located below the filter 400
  • Each of the pixel units of the fingerprint identification unit 301, that is, the aforementioned pixel array 302 may be arranged on the upper surface of the substrate 500.
  • the pixel array 302 and the substrate 500 may be referred to as a fingerprint sensor or an image sensor.
  • the filter 400 may also be grown on the surface of the pixel array 302 and integrated with the pixel array 302 in a fingerprint sensor or an image sensor.
  • the substrate may be the circuit board 150 in FIG. 1, which specifically may be a printed circuit board (PCB), a flexible printed circuit (FPC) or a flexible and hard board, etc., in the embodiment of the present application There is no restriction on this.
  • PCB printed circuit board
  • FPC flexible printed circuit
  • a flexible and hard board etc.
  • the number of light-blocking layers included in at least one light-blocking layer included in the fingerprint identification device is greater than three light-blocking layers.
  • the above fingerprint identification device may also include an image sensor drive unit, a microprogram controller and other devices.
  • the embodiment of the present application also provides an electronic device, which may include a display screen and the fingerprint identification device of the above-mentioned embodiment of the present application, wherein the fingerprint identification device is disposed under the display screen to realize off-screen optical fingerprint recognition.
  • the electronic device can be any electronic device with a display screen.
  • the display screen may be the display screen described above, such as an OLED display screen or other display screens.
  • the display screen refer to the description of the display screen in the above description.
  • a foam layer may be provided below the display screen, and the foam layer may be provided with at least one opening above the fingerprint identification device. The reflected light signal is transmitted to the fingerprint recognition device.
  • the black foam can be provided with an opening above the fingerprint identification device.
  • the finger When the finger is placed on top of the lit display screen, the finger will reflect the light emitted by the display screen. The reflected light reflected by the finger penetrates the display screen and is transmitted to the fingerprint identification device through at least one opening.
  • the fingerprint is a diffuse reflector, and its reflected light exists in all directions.
  • the specific light path in the fingerprint recognition device can be used to make the optical sensing pixel array in the fingerprint recognition device receive oblique light signals in multiple directions.
  • the processing unit in the fingerprint recognition device or the processing unit connected to the fingerprint recognition device The reconstructed fingerprint image can be obtained through the algorithm, and then the fingerprint identification can be performed.
  • the fingerprint identification device may output the collected image to a dedicated processor of a computer or a dedicated processor of an electronic device to perform fingerprint identification.
  • the processor of the embodiment of the present application may be an integrated circuit chip with signal processing capability.
  • the steps of the foregoing method embodiments can be completed by hardware integrated logic circuits in the processor or instructions in the form of software.
  • the above-mentioned processor may be a general-purpose processor, a digital signal processor (Digital Signal Processor, DSP), an application specific integrated circuit (ASIC), a ready-made programmable gate array (Field Programmable Gate Array, FPGA) or other Programming logic devices, discrete gates or transistor logic devices, discrete hardware components.
  • DSP Digital Signal Processor
  • ASIC application specific integrated circuit
  • FPGA Field Programmable Gate Array
  • the methods, steps, and logical block diagrams disclosed in the embodiments of the present application can be implemented or executed.
  • the general-purpose processor may be a microprocessor or the processor may also be any conventional processor or the like.
  • the steps of the method disclosed in the embodiments of the present application can be directly embodied as being executed and completed by a hardware decoding processor, or executed and completed by a combination of hardware and software modules in the decoding processor.
  • the software module can be located in a mature storage medium in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, registers.
  • the storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.
  • the fingerprint recognition in the embodiments of the present application may further include a memory
  • the memory may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memory.
  • the non-volatile memory can be read-only memory (Read-Only Memory, ROM), programmable read-only memory (Programmable ROM, PROM), erasable programmable read-only memory (Erasable PROM, EPROM), and electrically available Erase programmable read-only memory (Electrically EPROM, EEPROM) or flash memory.
  • the volatile memory may be random access memory (Random Access Memory, RAM), which is used as an external cache.
  • RAM random access memory
  • SRAM static random access memory
  • DRAM dynamic random access memory
  • DRAM synchronous dynamic random access memory
  • DDR SDRAM Double Data Rate Synchronous Dynamic Random Access Memory
  • Enhanced SDRAM, ESDRAM Enhanced Synchronous Dynamic Random Access Memory
  • Synchronous Link Dynamic Random Access Memory Synchronous Link Dynamic Random Access Memory
  • DR RAM Direct Rambus RAM
  • the disclosed system, device, and method can be implemented in other ways.
  • the device embodiments described above are merely illustrative, for example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components may be combined or It can be integrated into another system, or some features can be ignored or not implemented.
  • the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms.
  • the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.
  • the functional units in the various embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit.
  • the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium.
  • the technical solution of this application essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium.
  • a computer device which may be a personal computer, a server, or a network device, etc.
  • the aforementioned storage media include: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disk or optical disk and other media that can store program code .

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Abstract

一种指纹识别装置（300）和电子设备（30），能够提高指纹识别装置（300）的性能。指纹识别装置（300）包括密排排列的N个指纹识别单元（301），其中每个指纹识别单元（301）包括：圆形微透镜（310）；至少两层挡光层，设置在圆形微透镜（310）下方，至少两层挡光层中设置通光小孔以形成不同方向的M个导光通道，M为大于1的正整数；M个像素单元，分别位于该M个导光通道的底部；其中，从显示屏（120）上方的手指反射或散射后返回的光信号通过圆形微透镜（310）汇聚后，其中不同方向的M个目标指纹光信号分别经过M个导光通道传输至M个像素单元；N个指纹识别单元（301）中每个指纹识别单元（301）与六个指纹识别单元（301）相邻，且六个指纹识别单元中的六个圆形微透镜（310）的中心的连线构成正六边形。

Description

指纹识别装置和电子设备
本申请要求以下申请的优先权，其全部内容通过应用结合在本申请中：2019年10月18日提交中国专利局、申请号为PCT/CN2019/111978、发明名称为“指纹检测装置和电子设备”的PCT申请。
技术领域
本申请涉及光学指纹技术领域，并且更具体地，涉及一种指纹识别装置和电子设备。
背景技术
随着终端行业的高速发展，生物识别技术越来越受到人们重视，更加便捷的屏下生物特征识别技术，例如屏下指纹识别技术的实用化已成为大众所需。屏下指纹识别技术是将指纹识别装置设置于显示屏下，通过采集指纹图像，实现指纹识别。例如，指纹识别装置可以通过微透镜阵列将接收到的光信号汇聚至光电传感器中的像素阵列，光电传感器基于像素阵列接收到的光信号生成指纹图像，进而进行指纹识别。
在一些相关技术中，指纹识别装置中的微透镜阵列位于像素阵列的正上方，且一个微透镜对应一个像素单元，即微透镜阵列中的每一个微透镜将接收到的光线聚焦至同一微透镜对应的像素单元中，且多个像素单元呈阵列排列。采用该技术方案，指纹识别装置的整体进光量小，曝光时间长，整体成像质量较差，且对干手指的识别性能不佳。与此同时，指纹识别装置中的光路厚度厚，增加光路的加工难度以及成本，也不利于指纹识别装置轻薄化的发展。
因此，如何综合提高指纹识别装置的性能，是一项亟待解决的问题。
发明内容
本申请实施例提供了一种指纹识别装置和电子设备，能够提高指纹识别装置的性能。
第一方面，提供了一种指纹识别装置，适用于显示屏的下方以实现屏下光学指纹识别，该指纹识别装置包括密排排列的N个指纹识别单元，N为正 整数；该N个指纹识别单元中的每个指纹识别单元包括：圆形微透镜；至少两层挡光层，设置在该圆形微透镜下方，该至少两层挡光层中的每一层挡光层中设置通光小孔以形成不同方向的M个导光通道，M为大于1的正整数；M个像素单元，设置在该至少两层挡光层下方，该M个像素单元分别位于该M个导光通道的底部；其中，从该显示屏上方的手指反射或散射后返回的光信号通过该圆形微透镜汇聚后，其中不同方向的M个目标指纹光信号分别经过该M个导光通道传输至该M个像素单元，该M个目标指纹光信号用于检测该手指的指纹信息；该N个指纹识别单元中每个指纹识别单元与六个指纹识别单元相邻，且该六个指纹识别单元中的六个圆形微透镜的中心的连线构成正六边形。
通过本申请实施例的方案，N个指纹识别单元的每个指纹识别单元中，一个圆形微透镜对应M个像素单元，且M个像素单元分别接收经过该圆形微透镜汇聚并通过M个导光通道的M个方向的指纹光信号，该M个方向的指纹光信号分别被M个像素单元接收。相对于一个微透镜对应一个像素单元的技术方案，能够增大提高指纹识别装置的进光量，减小曝光时间，增大指纹识别装置的视场。并且，本申请实施例中，像素单元接收的指纹光信号的角度由该像素单元与微透镜的相对位置关系决定，若像素单元偏移微透镜的中心越远，则像素单元接收的指纹光信号的角度越大。因此，通过灵活设置像素单元的位置，可以使得像素单元可以接收大角度的指纹光信号，极大的改善干手指的识别问题，并且能够降低指纹识别单元中光路的厚度，从而减小指纹识别装置的厚度、降低工艺成本。另外，通过采用密排排列的多个指纹识别单元，使得指纹识别装置中多个圆形微透镜呈密排排列，能够提高多个圆形微透镜的占空比，增大指纹识别装置的进光量，进一步提高指纹图像的质量以及指纹识别性能。
在一种可能的实现方式中，该N个指纹识别单元中包括N×M个像素单元，用于接收不同方向的M个指纹光信号以形成M张指纹图像，该N个指纹识别单元中的N个像素单元用于接收一个方向的指纹光信号形成N个像素值，该N个像素值用于形成该M张指纹图像中的一张指纹图像，其中，该N个像素单元分别属于N个指纹识别单元；该M张指纹图像中的至少一张指纹图像用于进行指纹识别。
在一种可能的实现方式中，该N个像素单元的排列方式与该N个指纹 识别单元中N个圆形微透镜的排列方式相同。
在一种可能的实现方式中，该指纹识别装置还包括处理单元；该处理单元用于对该N个像素单元的N个像素值中每相邻的W个像素值之间插入一个插值像素，以得到一张像素值方形排列的指纹图像，其中，W为大于1的正整数。
在一种可能的实现方式中，W＝4，该插值像素为N个像素值中每相邻的4个像素值的均值。
在一种可能的实现方式中，该处理单元用于对该M张指纹图像进行上采样或者下采样，以调整该M张指纹图像横纵比，形成M张优化指纹图像。
在一种可能的实现方式中，该处理单元用于获取该M张优化指纹图像中的第一优化指纹图像和第二优化指纹图像，并获取该第一优化指纹图像中的第一区域；根据该第一区域的像素值，在该第二优化指纹图像中确定与该第一区域最接近的第二区域；计算该第一区域的坐标与该第二区域的坐标之差，移动该第一优化指纹图像与该第二优化指纹图像以形成第一重构图像；其中，该第一重构图像用于形成目标重构图像，该目标重构图像为该张优化指纹图像重构形成的图像，该目标重构图像用于进行指纹识别。
在一种可能的实现方式中，该处理单元用于移动该M张优化指纹图像以组合形成为一张重构图像，并根据该重构图像的质量参数，调整该M张指纹图像的移动距离，以形成目标重构图像，该目标重构图像用于进行指纹识别。
在一种可能的实现方式中，该N个指纹识别单元中的N个圆形微透镜中，相邻两个圆形微透镜的圆心距离小于75μm。
在一种可能的实现方式中，该M个导光通道的方向中一个导光通道的方向相对于该显示屏垂直，其它M-1个导光通道的方向相对于该显示屏倾斜；或者，该M个导光通道的方向均相对于该显示屏倾斜。
在一种可能的实现方式中，该M个导光通道分别与该显示屏的夹角在30°至90°之间。
在一种可能的实现方式中，该M个导光通道与该显示屏的夹角相同。
在一种可能的实现方式中，该M个导光通道中的两个导光通道在该多个像素单元所在平面上的投影的夹角为90度。
在一种可能的实现方式中，该M个像素单元中分别包括M个感光区域， 该M个感光区域分别位于该M个导光通道的底部。
在一种可能的实现方式中，该M个感光区域中的至少一个感光区域偏离于其所在的像素单元的中心设置。
在一种可能的实现方式中，该至少一个感光区域向远离于该圆形微透镜中心的方向偏离。
在一种可能的实现方式中，该M个像素单元包括第一像素单元，该第一像素单元中包括第一感光区域，该第一像素单元与该第一感光区域均为四边形；其中，该第一像素单元的长和宽分别为L和W，该第一感光区域的长和宽均大于等于0.1×W，W≤L，W和L均为正数。
在一种可能的实现方式中，该第一感光区域的面积大于等于该第一像素单元面积的95％。
在一种可能的实现方式中，该圆形微透镜与该M个像素单元所在平面之间的光路高度根据公式计算，该公式为：h＝x×cotθ；其中，h为该光路高度，x为该M个感光区域中的第一感光区域的中心与该圆形微透镜的中心在该M个像素单元所在平面上的投影点之间的距离，θ为该第一感光区域接收的第一目标指纹光信号与垂直方向的夹角，该M个目标指纹光信号中该第一目标指纹光信号与垂直方向的夹角大于该M个目标指纹光信号中其它目标指纹光信号与垂直方向的夹角，该垂直方向为垂直于该显示屏的方向。
在一种可能的实现方式中，该至少两层挡光层中的底层挡光层设置有与该M个像素单元分别对应的M个通光小孔。
在一种可能的实现方式中，该至少两层挡光层中的底层挡光层为该M个像素单元表面的金属布线层。
在一种可能的实现方式中，该M个导光通道中的通光小孔由上至下孔径依次减小。
在一种可能的实现方式中，该M个导光通道在该至少两层挡光层的顶层挡光层中的通光小孔重合。
在一种可能的实现方式中，该指纹识别单元还包括：透明介质层；其中，该透镜介质层用于连接该圆形微透镜、该至少两层挡光层以及该M个像素单元。
在一种可能的实现方式中，该指纹识别单元还包括：光学滤波层；其中，该光学滤波层设置在该显示屏到该M个像素单元所在平面之间的光路中， 用于滤除非目标波段的光信号，以透过目标波段的光信号。
在一种可能的实现方式中，该光学滤波层集成于该M个像素单元表面。
在一种可能的实现方式中，该光学滤波层设置在该至少两层挡光层的底层挡光层与该M个像素单元所在平面之间。
在一种可能的实现方式中，该指纹识别装置和该显示屏之间的距离为0至1mm。
第二方面，提供了一种电子设备，包括如第一方面或第一方面的任一可能的实现方式中的指纹识别装置，该指纹识别装置设置于该显示屏下方，以实现屏下光学指纹识别。
在一种可能的实现方式中，该指纹识别装置和该显示屏之间的距离为0至1mm。
在电子设备中设置上述指纹识别装置，通过提升指纹识别装置的指纹识别性能，从而提升该电子设备的指纹识别性能。
附图说明
图1为本申请实施例所适用的电子设备的结构示意图。
图2和图3为根据本申请实施例的一种指纹识别装置的示意性截面图和示意性俯视图。
图4为根据本申请实施例的一种指纹识别装置的示意性俯视图。
图5a为根据本申请实施例的指纹识别单元一种示意性立体结构图。
图5b为图5a中指纹识别单元的俯视图。
图5c为图5a中多个指纹识别单元密排排列的俯视图。
图6a为根据本申请实施例的指纹识别单元另一示意性立体结构图。
图6b为图6a中指纹识别单元的俯视图。
图6c为图6a中多个指纹识别单元密排排列的俯视图。
图7a为根据本申请实施例的指纹识别单元另一示意性立体结构图。
图7b为图7a中指纹识别单元的俯视图。
图7c为图7a中多个指纹识别单元密排排列的俯视图。
图8a和图8b为根据本申请实施例的两种多个指纹识别单元中多个第一像素单元和多个第二像素单元的排列示意图。
图9为根据本申请实施例的多个指纹识别单元中多个第一像素单元、多 个第二像素单元、多个第三像素单元以及多个第四像素单元的一种排列示意图。
图10为根据本申请实施例的一种多个第一像素单元的原始像素值的数据结构。
图11为根据本申请实施例的插值处理后形成的一种方形阵列排列的数据结构。
图12为根据本申请实施例的另一多个第一像素单元的原始像素值的数据结构。
图13为根据本申请实施例的插值处理后形成的另一方形阵列排列的数据结构。
图14为根据本申请实施例的一种指纹识别单元的示意性俯视图。
图15为图14中指纹识别单元沿A-A’方向的截面示意图。
图16为根据本申请实施例的另一指纹识别单元的示意性俯视图。
图17为图16中指纹识别单元沿A-A’方向的截面示意图。
图18为根据本申请实施例的另一指纹识别单元的示意性俯视图。
图19为根据本申请实施例的另一指纹识别单元的示意性俯视图。
图20为根据本申请实施例的另一指纹识别单元的示意性俯视图。
图21为根据本申请实施例的另一指纹识别单元的示意性俯视图。
图22为根据本申请实施例的一种电子设备的示意性结构图。
具体实施方式
下面将结合附图，对本申请实施例中的技术方案进行描述。
应理解，本申请实施例可以应用于光学指纹系统，包括但不限于光学指纹识别系统和基于光学指纹成像的产品，本申请实施例仅以光学指纹系统为例进行说明，但不应对本申请实施例构成任何限定，本申请实施例同样适用于其他采用光学成像技术的系统等。
作为一种常见的应用场景，本申请实施例提供的光学指纹系统可以应用在智能手机、平板电脑以及其他具有显示屏的移动终端或者其他电子设备；更具体地，在上述电子设备中，指纹识别装置可以具体为光学指纹装置，其可以设置在显示屏下方的局部区域或者全部区域，从而形成屏下(Under-display)光学指纹系统。或者，该指纹识别装置也可以部分或者全 部集成至电子设备的显示屏内部，从而形成屏内(In-display)光学指纹系统。
如图1所示为本申请实施例可以适用的电子设备的结构示意图，该电子设备10包括显示屏120和光学指纹装置130，其中，该光学指纹装置130设置在显示屏120下方的局部区域。该光学指纹装置130包括光学指纹传感器，该光学指纹传感器包括具有多个光学感应单元131的感应阵列133，该感应阵列133所在区域或者其感应区域为光学指纹装置130的指纹检测区域103。如图1所示，指纹检测区域103位于显示屏120的显示区域之中。在一种替代实施例中，光学指纹装置130还可以设置在其他位置，比如显示屏120的侧面或者电子设备10的边缘非透光区域，并通过光路设计来将显示屏120的至少部分显示区域的光信号导引到光学指纹装置130，从而使得指纹检测区域103实际上位于显示屏120的显示区域。
应当理解，指纹检测区域103的面积可以与光学指纹装置130的感应阵列的面积不同，例如通过例如透镜成像的光路设计、反射式折叠光路设计或者其他光线汇聚或者反射等光路设计，可以使得光学指纹装置130的指纹检测区域103的面积大于光学指纹装置130感应阵列的面积。在其他替代实现方式中，如果采用例如光线准直方式进行光路引导，光学指纹装置130的指纹检测区域103也可以设计成与该光学指纹装置130的感应阵列的面积基本一致。
因此，使用者在需要对电子设备进行解锁或者其他指纹验证的时候，只需要将手指按压在位于显示屏120的指纹检测区域103，便可以实现指纹输入。由于指纹检测可以在屏内实现，因此采用上述结构的电子设备10无需其正面专门预留空间来设置指纹按键(比如Home键)，从而可以采用全面屏方案，即显示屏120的显示区域可以基本扩展到整个电子设备10的正面。
作为一种可选的实现方式，如图1所示，光学指纹装置130包括光检测部分134和光学组件132，该光检测部分134包括感应阵列以及与该感应阵列电性连接的读取电路及其他辅助电路，其可以在通过半导体工艺制作在一个芯片(Die)，比如光学成像芯片或者光学指纹传感器，该感应阵列具体为光探测器(Photo detector)阵列，其包括多个呈阵列式分布的光探测器，该光探测器可以作为上述的光学感应单元；该光学组件132可以设置在光检测部分134的感应阵列的上方，其可以具体包括导光层或光路引导结构以及其他光学元件，该导光层或光路引导结构主要用于从手指表面反射回来的反射光 导引至感应阵列进行光学检测。
在具体实现上，光学组件132可以与光检测部分134封装在同一个光学指纹部件。比如，该光学组件132可以与该光学检测部分134封装在同一个光学指纹芯片，也可以将该光学组件132设置在该光检测部分134所在的芯片外部，比如将该光学组件132贴合在该芯片上方，或者将该光学组件132的部分元件集成在上述芯片之中。
其中，光学组件132的导光层或者光路引导结构有多种实现方案，比如，该导光层可以具体为在半导体硅片制作而成的准直器(Collimator)层，其具有多个准直单元或者微孔阵列，该准直单元可以具体为小孔，从手指反射回来的反射光中，垂直入射到该准直单元的光线可以穿过并被其下方的光学感应单元接收，而入射角度过大的光线在该准直单元内部经过多次反射被衰减掉，因此每一个光学感应单元基本只能接收到其正上方的指纹纹路反射回来的反射光，从而感应阵列便可以检测出手指的指纹图像。
在另一种实施例中，导光层或者光路引导结构也可以为光学透镜(Lens)层，其具有一个或多个透镜单元，比如一个或多个非球面透镜组成的透镜组，其用于将从手指反射回来的反射光汇聚到其下方的光检测部分134的感应阵列，以使得该感应阵列可以基于该反射光进行成像，从而得到该手指的指纹图像。可选地，该光学透镜层在该透镜单元的光路中还可以形成有针孔，该针孔可以配合该光学透镜层扩大光学指纹装置的视场，以提高光学指纹装置130的指纹成像效果。
在其他实施例中，导光层或者光路引导结构也可以具体采用微透镜(Micro-Lens)层，该微透镜层具有由多个微透镜形成的微透镜阵列，其可以通过半导体生长工艺或者其他工艺形成在光检测部分134的感应阵列上方，并且每一个微透镜可以分别对应于感应阵列的其中一个感应单元。并且，微透镜层和感应单元之间还可以形成其他光学膜层，比如介质层或者钝化层，更具体地，微透镜层和感应单元之间还可以包括具有微孔的挡光层，其中该微孔形成在其对应的微透镜和感应单元之间，挡光层可以阻挡相邻微透镜和感应单元之间的光学干扰，并使得感应单元所对应的光线通过微透镜汇聚到微孔内部并经由该微孔传输到该感应单元以进行光学指纹成像。应当理解，上述光路引导结构的几种实现方案可以单独使用也可以结合使用，比如，可以在准直器层或者光学透镜层下方进一步设置微透镜层。当然，在准直器 层或者光学透镜层与微透镜层结合使用时，其具体叠层结构或者光路可能需要按照实际需要进行调整。
作为一种可选的实施例，显示屏120可以采用具有自发光显示单元的显示屏，比如有机发光二极管(Organic Light-Emitting Diode，OLED)显示屏或者微型发光二极管(Micro-LED)显示屏。以采用OLED显示屏为例，光学指纹装置130可以利用OLED显示屏120位于指纹检测区域103的显示单元(即OLED光源)来作为光学指纹检测的激励光源。当手指140按压在指纹检测区域103时，显示屏120向指纹检测区域103上方的目标手指140发出一束光111，该光111在手指140的表面发生反射形成反射光或者经过手指140内部散射而形成散射光，在相关专利申请中，为便于描述，上述反射光和散射光统称为反射光。由于指纹的脊(ridge)与谷(valley)对于光的反射能力不同，因此，来自指纹脊的反射光151和来自指纹谷的反射光152具有不同的光强，反射光经过光学组件132后，被光学指纹装置130中的感应阵列134所接收并转换为相应的电信号，即指纹检测信号；基于该指纹检测信号便可以获得指纹图像数据，并且可以进一步进行指纹匹配验证，从而在电子设备10实现光学指纹识别功能。
在其他实施例中，光学指纹装置130也可以采用内置光源或者外置光源来提供用于进行指纹检测的光信号。在这种情况下，该光学指纹装置130可以适用于非自发光显示屏，比如液晶显示屏或者其他的被动发光显示屏。以应用在具有背光模组和液晶面板的液晶显示屏为例，为支持液晶显示屏的屏下指纹检测，电子设备10的光学指纹系统还可以包括用于光学指纹检测的激励光源，该激励光源可以具体为红外光源或者特定波长非可见光的光源，其可以设置在液晶显示屏的背光模组下方或者设置在电子设备10的保护盖板下方的边缘区域，而光学指纹装置130可以设置液晶面板或者保护盖板的边缘区域下方并通过光路引导以使得指纹检测光可以到达光学指纹装置130；或者，光学指纹装置130也可以设置在背光模组下方，且背光模组通过对扩散片、增亮片、反射片等膜层进行开孔或者其他光学设计以允许指纹检测光穿过液晶面板和背光模组并到达光学指纹装置130。当采用光学指纹装置130采用内置光源或者外置光源来提供用于进行指纹检测的光信号时，其检测原理与上面描述内容是一致的。
应当理解的是，在具体实现上，电子设备10还包括透明保护盖板，该 盖板可以为玻璃盖板或者蓝宝石盖板，其位于显示屏120的上方并覆盖电子设备10的正面。因为，本申请实施例中，所谓的手指按压在显示屏120实际上是指按压在显示屏120上方的盖板或者覆盖该盖板的保护层表面。
还应当理解，电子设备10还可以包括电路板150，该电路板设置在光学指纹装置130的下方。光学指纹装置130可以通过背胶粘接在电路板150上，并通过焊盘及金属线焊接与电路板150实现电性连接。光学指纹装置130可以通过电路板150实现与其他外围电路或者电子设备10的其他元件的电性互连和信号传输。比如，光学指纹装置130可以通过电路板150接收电子设备10的处理单元的控制信号，并且还可以通过电路板150将来自光学指纹装置130的指纹检测信号输出给电子设备10的处理单元或者控制单元等。
另一方面，在某些实施例中，光学指纹装置130可以仅包括一个光学指纹传感器，此时光学指纹装置130的指纹检测区域103的面积较小且位置固定，因此用户在进行指纹输入时需要将手指按压到指纹检测区域103的特定位置，否则光学指纹装置130可能无法采集到指纹图像而造成用户体验不佳。在其他替代实施例中，光学指纹装置130可以具体包括多个光学指纹传感器；该多个光学指纹传感器可以通过拼接方式并排设置在显示屏120的下方，且该多个光学指纹传感器的感应区域共同构成光学指纹装置130的指纹检测区域103。也即是说，光学指纹装置130的指纹检测区域103可以包括多个子区域，每个子区域分别对应于其中一个光学指纹传感器的感应区域，从而将光学指纹装置130的指纹采集区域103可以扩展到显示屏的下半部分的主要区域，即扩展到手指惯常按压区域，从而实现盲按式指纹输入操作。可替代地，当光学指纹传感器数量足够时，指纹检测区域103还可以扩展到半个显示区域甚至整个显示区域，从而实现半屏或者全屏指纹检测。
还应理解，在本申请实施例中，光学指纹装置中的感应阵列也可以称为像素阵列，感应阵列中的光学感应单元或感应单元也可称为像素单元。
需要说明的是，本申请实施例中的光学指纹装置也可以称为光学指纹识别模组、指纹识别装置、指纹识别模组、指纹模组、指纹采集装置等，上述术语可相互替换。
图2和图3示出了一种指纹识别装置的示意性截面图和示意性俯视图。
如图2和图3所示，指纹识别装置200包括微透镜阵列210、至少一层挡光层220和像素阵列230。微透镜阵列210位于像素阵列230和至少一层 挡光层220的正上方，且一个微透镜211对应一个像素单元231，即微透镜阵列210中的每一个微透镜211将接收到的光线通过至少一层挡光层220的小孔221聚焦至同一微透镜211对应的像素单元231中。其中，每一个微透镜211接收的光信号主要为经过显示屏上方手指反射或散射后垂直于微透镜阵列210入射的指纹光信号。
如图3所示，像素阵列230中的像素单元231按照周期性排列，且像素阵列230中的每一个像素单元231的感光区域2311均设置在同一个像素单元的中心位置，以提高感光区域的占空比。
换言之，微透镜阵列210中的多个微透镜211和像素阵列230中的多个像素单元231一一对应，且像素阵列230中多个像素单元231的感光区域2311呈周期性排列且均匀分布。
但是，像素阵列230的感光区域会受到微透镜阵列210的尺寸的影响，且指纹识别装置200的厚度较大，进而增加了指纹识别装置200的光路的加工难度、周期以及成本。
此外，在正常生活场景下，例如洗完手、早晨起床、手指抹灰、低温等场景下手指通常较干，其角质层不均匀，其按压在显示屏上时，手指局部区域会出现接触不良。当干手指与显示屏接触不好时，上述指纹识别装置200形成的垂直方向的指纹图像的指纹脊和指纹谷的对比度差，图像模糊到分辨不了指纹纹路，因而，上述指纹识别装置200对于干手指的指纹识别性能较差。
另外，在以上图3的指纹识别装置200中，微透镜阵列210中的多个圆形微透镜呈方形阵列排列，四个相邻的圆形微透镜的圆心构成一个正方形。
理想情况下，水平或者垂直方向上，两个相邻的圆形微透镜互相相切。但由于制造工艺的精度限制，两个相邻的圆形微透镜之间存在一定的间隙，该间隙也称为关键尺寸(Critical Dimension，CD)，在不同的工艺制程条件下，CD值不同。CD越小，则表明工艺制程精度更高，同时成本也更高。
在此情况下，微透镜阵列210所在区域中有效的聚光区域面积为多个圆形微透镜的面积之和，相比于非聚光的平面区域，圆形微透镜能够增大视场，接收更大范围内的光信号，从而提高单位面积内接收的光信号的强度。而微透镜阵列210中多个圆形微透镜之间的空隙则不是聚光区域，无聚光作用，无法提高单位面积内接收的光信号的强度。
在本申请实施例中，多个圆形微透镜的面积之和与微透镜阵列所在区域的面积之比，或者多个圆形微透镜的面积之和与像素阵列的面积之比，也写为微透镜的占空比，可以用来表征微透镜阵列接收光信号能力的强弱，占空比越大，则微透镜阵列用于汇聚光信号的区域越多，光强增大。
在图3所示的指纹识别装置200中，微透镜阵列210的占空比为单位周期区域上一个圆形微透镜的面积与其所在区域的面积之比。具体的计算公式为：D＝πR 2/(2R+a) 2，其中，D为微透镜阵列的占空比，R为圆形微透镜的半径，a为相邻的两个圆形微透镜之间的CD值。
当理想情况下，a为0时，若R为5.75μm，微透镜阵列210的占空比D＝π×5.75 2/(2×5.75) 2＝π/4＝78.54％。
当a为1μm，R为5.75μm时，微透镜阵列210的占空比D＝π×5.75 2/(2×5.75+1) 2＝66.48％。
由上述说明与计算可知，理想情况下，相邻圆形微透镜之间的CD值为0，微透镜阵列230的占空比为78.54％，而非理想情况下，相邻圆形微透镜之间的CD值大于0，微透镜阵列230的占空比小于理想情况下的78.54％，用于聚光的微透镜面积占比不大，因而像素阵列接收的光信号强度也不大，指纹识别装置200的进光量相对较小，曝光时间长。
基于上述问题，本申请实施例中，提供一种指纹识别装置，能够提高指纹识别装置的进光量、减小曝光时间、提高光学分辨率以及光学视场，还能够进一步优化干手指的识别性能，减小指纹识别装置的厚度。
以下，结合图4至图21，详细介绍本申请实施例的指纹识别装置。
需要说明的是，为便于理解，在以下示出的实施例中，相同的结构采用相同的附图标记，并且为了简洁，省略对相同结构的详细说明。
应理解，在以下所示出的本申请实施例中的像素单元、微透镜以及阻光层上通光小孔的数量和排布方式等仅为示例性说明，而不应对本申请构成任何限定。
图4是本申请实施例提供的一种指纹识别装置300的示意性俯视图，该指纹识别装置300适用于显示屏的下方，以实现屏下光学指纹识别。
如图4所示，该指纹识别装置300可以包括呈密排排列的N个指纹识别单元301，该密排排列也可以称为六角形排列，其中，N为正整数。
在本申请实施例中，N个指纹识别单元301中每个指纹识别单元301均 包括：圆形微透镜，则N个指纹识别单元301中包括N个圆形微透镜，该N个圆形微透镜同N个指纹识别单元的排列方式相同，也呈密排排列。如图4所示，位于中心的指纹识别单元301与周围的六个指纹识别单元301相邻，该六个指纹识别单元301中的圆形微透镜的中心的连线构成正六边形。
在本申请实施例中，N个指纹识别单元中每个指纹识别单元与六个指纹识别单元相邻，且该六个指纹识别单元中的六个圆形微透镜的中心的连线构成正六边形。
应理解，本申请实施例中的N个指纹识别单元的数量较多，且N个指纹识别单元中N个圆形微透镜的整体一般形成规则图形，例如，四边形等图形。
还应理解，N个指纹识别单元的整体的周围还设置有多个边缘指纹识别单元，该多个边缘指纹识别单元中每个边缘指纹识别单元的结构与N个指纹识别单元的结构相同，与该多个边缘指纹识别单元相邻的指纹识别单元的数量小于六个，但本申请实施例中的指纹识别装置也可以包括该多个边缘指纹识别单元，使得所有的指纹识别单元的整体形成规则图形，例如，四边形等图形。
可选地，该多个圆形微透镜中任意两个相邻的圆形微透镜之间的距离相等。
在一种可能的实施方式中，如图4所示，多个圆形微透镜中任意两个相邻的圆形微透镜相切，两个相邻的圆形微透镜的距离为0。该多个圆形微透镜交错相接排列。
在另一种可能的实施方式中，多个圆形微透镜中任意两个相邻的圆形微透镜之间存在一定的间隙距离，该间隙由制造工艺中的关键尺寸CD决定。此时，该多个圆形微透镜交错相间排列，且多个圆形微透镜中任意两个相邻的圆形微透镜之间的CD间隙相等。
下面，以图4为例，计算说明指纹识别装置300中N个圆形微透镜的占空比。
以图中菱形区域为周期区域计算此时N个圆形微透镜的占空比。在该菱形的周期区域中，菱形的顶点位于四个圆形微透镜的圆心，该菱形区域包括一个完整的圆形微透镜，该情况下，微透镜阵列310的占空比D的计算公式为：
Figure PCTCN2020073901-appb-000001
其中，R为圆形微透镜的半径，a为相邻的两个圆形微透镜之间的CD值。
当理想情况下，a为0时，若R为5.75μm，指纹识别装置300中N个圆形微透镜阵列的占空比为：
Figure PCTCN2020073901-appb-000002
当a为1μm，R为5.75μm时，指纹识别装置300中N个圆形微透镜阵列的占空比为：
Figure PCTCN2020073901-appb-000003
通过计算可知，在此情况下，N个圆形微透镜的占空比大于图3中微透镜阵列210的占空比，通过调整多个圆形微透镜的位置关系，能够提高多个圆形微透镜的占空比，增大指纹识别装置的进光量，从而提高指纹图像的质量以及指纹识别性能。
除圆形微透镜外，本申请实施例中N个指纹识别单元中的每个指纹识别单元301还包括：
至少两层挡光层，设置在圆形微透镜下方，该至少两层挡光层中的每一层挡光层中设置通光小孔以形成不同方向的M个导光通道，M为大于1的正整数；
M个像素单元，设置在该至少两层挡光层下方，该M个像素单元分布位于上述M个导光通道的底部；
其中，从显示屏上方的手指反射或散射后返回的光信号通过圆形微透镜汇聚后，其中不同方向的M个目标指纹光信号分别经过上述M个导光通道传输至上述M个像素单元，该M个目标指纹光信号用于检测手指的指纹信息。
具体地，上述圆形微透镜可以是各种具有汇聚功能的镜头，用于增大视场，增加传输至像素单元的光信号量。该圆形微透镜的材料为透明材料，例如树脂、玻璃等等。
具体地，M个像素单元可以为一种光电转换单元。可选地，该像素单元可以包括互补金属氧化物半导体(Complementary Metal Oxide  Semiconductor，CMOS)器件，具体包括光电二极管(Photo Diode，PD)以及CMOS开关管等等，其中，光电二极管为由一个PN结组成的半导体器件，具有单方向导电特性，其可以将接收的光信号转换为对应的电信号，从而实现光图像至电图像的转换，CMOS开关管用于接收控制信号控制光电二极管的工作，并可以用于控制输出光电二极管的电信号。
具体地，至少两层挡光层为形成与圆形微透镜与M个像素单元之间的介质层，其可以为不透光的有机材料层或者为金属层。在该至少两层挡光层上进行小孔图像光刻和刻蚀，形成多个通光小孔，至少两层上的多个通光小孔可以形成不同方向的多个导光通道，用于引导不同方向的光信号进入位于导光通道底部的像素单元。
应理解，在具体实现中，本领域技术人员可以根据光路设计要求确定导光通道的方向，从而确定至少两层挡光层中通光小孔的分布，形成满足光路设计要求的导光通道，通过特定方向的目标指纹光信号被像素单元接收。
在具体实现中，至少两层挡光层中的每层挡光层对特定波段(比如可见光或者610nm以上波段)的光的透过率小于预设阈值(例如20％)，以避免相应的光通过。其中的通光小孔可以为圆柱形通孔，也可以为其它形状的通孔，例如多边形通孔。该通光小孔的孔径可以大于预定值，例如，该通光小孔的孔径大于100nm，以便于透过所需的光以进行成像。该通光小孔的孔径也要小于预定值，以确保挡光层能够阻挡不需要的光。又例如，该通光小孔的孔径可以小于微透镜的直径。
作为示例，至少两层挡光层中的通光小孔也可以包括通过多个小孔径的开孔等效合成的大孔径开孔。例如，可以将至少两层挡光层中的顶层挡光层中的用于传输同一微透镜汇聚的光信号的多个小孔径开孔合并为一个大孔径开孔。
可选地，至少两层挡光层中的每层挡光层可以为金属层，相应地，挡光层内设置的通光小孔可以为形成在金属层的通孔。至少两层挡光层中的挡光层也可以是黑色高分子吸光材料。例如，针对大于预设角度的光信号，该至少两层挡光层具有小于2％的可见光波段透过率。
应理解，挡光层中的通光小孔的参数设置应尽可能使得成像所需的光信号最大化地传输至像素单元，而不需要的光被最大化地阻挡。例如，该通光小孔的参数可以设置为使得以特定角度(例如35度)倾斜入射的光信号最 大化的传输至对应的像素单元，而最大化阻挡其他光信号。
在本申请的一些实施例中，上述指纹识别单元301还可以包括透明介质层。
其中，该透镜介质层用于连接圆形微透镜310、至少两层挡光层以及M个像素单元。
例如，透明介质层可透过目标波段的光信号(即指纹识别所需波段的光信号)。例如，透明介质层可采用氧化物或氮化物等。可选地，透明介质层可以包括多层，以分别实现保护、过渡和缓冲等功能。例如，在无机层和有机层之间可以设置过渡层，以实现紧密的连接；在易氧化的层上可以设置保护层，以实现保护。
在本申请的一些实施例中，上述指纹识别单元301还可以包括光学滤波层。
其中，所述光学滤波层设置在圆形微透镜310到M个像素单元所在平面之间的光路中或者设置在圆形微透镜310上方，该光学滤波层用于滤除非目标波段的光信号，以透过目标波段的光信号。
例如，该光学滤波层对目标波段的光的透过率可以大于或等于预设阈值，对非目标波段的光的截止率可以大于或等于所述预设阈值。例如，所述预设阈值可以是80％。可选地，该光学滤波层可以为独立形成的光学滤波层。例如，该光学滤波层可以是采用蓝水晶或者蓝玻璃做载体形成的光学滤波层。可选地，该光学滤波层可以为形成在圆形微透镜310到M个像素单元所在平面之间的光路中任一层表面的镀膜。例如，可以在像素单元的表面、透明介质层中任一层的表面或微透镜的表面形成的镀膜，进而形成光学滤波层。
可选地，当至少两层挡光层均位于M个像素单元上方，而非M个像素单元表面时，光学滤波层设置在至少两层挡光层的底层挡光层与M个像素单元所在平面之间。
可选地，当至少两层挡光层的底层挡光层为M个像素单元表面的金属布线层时，光学滤波层设置在该底层挡光层与其上方的挡光层之间。
可选地，该光学滤波层可以生长于M个像素单元所在的传感器芯片的表面，并集成在该传感器芯片中。
可选地，可以采用物理气相沉积(Physical Vapour Deposition，PVD)工 艺在M个像素单元上进行镀膜形成光学滤波层，例如，通过原子层沉积、溅射镀膜、电子束蒸发镀膜、离子束镀膜等方法在像素单元上方制备多层滤光材料薄膜。
可选地，在本申请实施例中，光学滤波层包括多层氧化物薄膜，其中，该多层氧化物薄膜包括硅氧化物薄膜和钛氧化物薄膜，该硅氧化物薄膜和钛氧化物薄膜依次交替生长形成该光学滤波层；或者该多层氧化物薄膜包括硅氧化物薄膜和铌氧化物薄膜，该硅氧化物薄膜和铌氧化物薄膜依次交替生长形成该光学滤波层。
可选地，本申请实施例中，光学滤波层的厚度在1μm至10μm之间。
可选地，光学滤波层用于通过400nm至650nm波段范围的光信号，换言之，上述目标波段的波长范围包括400nm至650nm。
此处需要说明的是，本申请指纹识别装置300中的N个指纹识别单元301在结构上不是独立的单元结构，换言之，该指纹识别装置300不是由N个指纹识别单元301拼接形成，而是在形成该指纹识别装置300中的结构后，为了便于理解，将指纹识别装置300划分为周期性排列的多个指纹识别单元301。
可选地，图5a示出了上述指纹识别单元301的一种示意性立体结构图。图5b为该指纹识别单元301的俯视图。图5c为该指纹识别单元301形成的指纹识别装置的俯视图。
如图5a和图5b所示，指纹识别单元301包括：
圆形微透镜310；
两层挡光层，设置在圆形微透镜310下方，该两层挡光层中的每一层挡光层中设置通光小孔以形成不同方向的2个导光通道；
2个像素单元(第一像素单元331和第二像素单元332)，设置在该两层挡光层下方，该2个像素单元分布位于上述2个导光通道的底部。
可选地，如图5a和图5b所示，指纹识别单元301中的两个像素单元可以为长方形，该两个长方形的像素单元对应于圆形微透镜310，并设置于圆形微透镜310下方。
可选地，图6a示出了上述指纹识别单元301的另一种示意性立体结构图。图6b图为该指纹识别单元301的俯视图。图6c图为该指纹识别单元301形成的指纹识别装置的俯视图。
如图6a和图6b所示，指纹识别单元301包括：
圆形微透镜310；
两层挡光层，设置在圆形微透镜310下方，该两层挡光层中的每一层挡光层中设置通光小孔以形成不同方向的3个导光通道；
3个像素单元(第一像素单元331、第二像素单元332和第三像素单元333)，设置在该两层挡光层下方，该3个像素单元分布位于上述3个导光通道的底部。
可选地，图7a示出了上述指纹识别单元301的另一种示意性立体结构图。图7b为该指纹识别单元301的俯视图。图7c为指纹识别装置中多个该指纹识别单元301密排排列的俯视图。
如图7a和图7b所示，指纹识别单元301包括：
圆形微透镜310；
两层挡光层，设置在圆形微透镜310下方，该两层挡光层中的每一层挡光层中设置通光小孔以形成不同方向的4个导光通道；
4个像素单元(第一像素单元331、第二像素单元332、第三像素单元333和第四像素单元334)，设置在该两层挡光层下方，该4个像素单元分布位于上述4个导光通道的底部。
可选地，该圆形微透镜310的直径不大于四个像素单元的排列周期。例如，若四个像素单元所在区域为A×B的四边形区域，其中，A≤B，A与B为正整数，则微透镜310的直径小于等于A。
可选地，该指纹检测单元301中的四个像素单元可以为四边形像素，例如，形状大小相同的正方形像素。
可选地，在上述图5至图7三种指纹识别单元中，该圆形微透镜的上表面为球面或者非球面，该圆形微透镜310的直径不大于M个像素单元的排列周期。例如，若M个像素单元所在区域为A×B的四边形区域，其中，A≤B，A与B为正整数，则圆形微透镜310的直径小于等于A。
此处需要说明的是，设置于圆形微透镜310下方的M个像素单元还可以为异形图案，以使得指纹识别装置300中的像素阵列具有更高的对称性，更高的采样效率，相邻像素等距，更好的角度分辨率，更少的混迭效应。
上述图5a至图7a的三种指纹识别单元中，两层挡光层包括第一挡光层321和第二挡光层322。该第一挡光层321形成于圆形微透镜310与M个像 素单元所在平面之间的任意位置，本申请实施例对此不做限定。
该第二挡光层322在图5a至图7a中未示中，其可以形成于M个像素单元的表面，具体可以为M个像素单元表面的金属层。
当然，该第二挡光层322还可以形成于圆形微透镜310与M个像素单元所在平面之间的任意位置，例如，形成于第一挡光层321与M个像素单元所在平面之间，本申请实施例同样对此不做具体限定。
可选地，如图5a至图7a所示，第一挡光层321上形成有第一通光小孔3211，第二挡光层322上形成有N个通光小孔，例如，如图5a和图5b所示，第二挡光层332上形成有2个通光小孔，分别为第二通光小孔3221和第三通光小孔3222。该第二通光小孔3221和第一通光小孔3211形成第一导光通道，用于通过经过圆形微透镜310汇聚后的指纹光信号中的第一目标指纹光信号，其被位于第一导光通道底部的第一像素单元331接收，用于检测指纹信息。同样的，第三通光小孔3222和第一通光小孔3211形成第二导光通道，用于通过第二目标指纹光信号，其被位于第二导光通道底部的第二像素单元332接收，该第一目标指纹光信号和第二目标指纹光信号用于检测指纹信息。
在本申请实施例中，第一通光小孔3211、第二通光小孔3321和第三通光小孔3222可以位于圆形微透镜310下方的任意位置，旨在形成任意两个不同方向的导光通道。换言之，圆形微透镜310对应的第一像素单元331和第二像素单元332也可以位于圆形微透镜310下方的任意位置，旨在接收经过两个不同方向的导光通道的两个不同方向的指纹光信号。
类似地，如图6a和图6b所示，第二挡光层332上形成有3个通光小孔，该3个通光小孔分别与第一挡光层331上的通光小孔共同形成3个像素单元的3个不同方向的导光通道。类似地，如图7a和图7b所示，第二挡光层332上形成有4个通光小孔，该4个通光小孔分别与第一挡光层331上的通光小孔共同形成4个像素单元的4个不同方向的导光通道。
可选地，通过调整M个像素单元与圆形微透镜310之间的相对位置关系，并在M个像素单元与圆形微透镜310之间通过在挡光层上开小孔构建导光通道，以通过不同方向的指纹光信号，从而使得M个像素单元中的感光区域接收不同方向的指纹光信号。
可选地，还可以通过调整M个像素单元中感光区域的面积和/或感光区域在像素单元中的相对位置关系，使得M个像素单元中的感光区域接收不 同方向的指纹光信号。
上文以指纹识别单元301中包括2至4个像素单元为例，对指纹识别装置进行了举例说明，应理解，指纹识别单元中还可以包括4个以上任意数量的像素单元，本申请对每个指纹识别单元中的像素单元数量不做具体限定。
通过本申请实施例的方案，一个圆形微透镜对应M个像素单元，且M个像素单元分别接收经过该圆形微透镜汇聚并通过M个导光通道的M个方向的指纹光信号，该M个方向的指纹光信号分别被M个像素单元接收。相对于一个微透镜对应一个像素单元的技术方案(例如图2与图3中的指纹识别装置)，能够增大提高指纹识别装置的进光量，减小曝光时间，增大指纹识别装置的视场。并且，本申请实施例中，像素单元接收的指纹光信号的角度(指纹光信号与垂直于显示屏方向的夹角)由该像素单元与微透镜的相对位置关系决定，若像素单元偏移微透镜的中心越远，则像素单元接收的指纹光信号的角度越大。因此，通过灵活设置像素单元的位置，可以使得像素单元可以接收大角度的指纹光信号，极大的改善干手指的识别问题，并且能够降低指纹识别单元中光路的厚度，从而减小指纹识别装置的厚度、降低工艺成本。
此外，本申请实施例的方案中，通过采用密排排列的多个指纹识别单元，使得指纹识别装置中多个圆形微透镜呈密排排列，能够提高多个圆形微透镜的占空比，增大指纹识别装置的进光量，进一步提高指纹图像的质量以及指纹识别性能。
综上，采用本申请实施例的技术方案，在改善干手指的识别问题、降低指纹识别装置的厚度、降低工艺成本的同时，能够提高指纹识别装置的进光量、减小曝光时间、提高光学分辨率以及光学视场，进一步提高指纹图像的质量以及指纹识别性能。
如上所述，在N个指纹识别单元中，每个指纹识别单元包括M个像素单元，则在指纹识别装置中，共包括N×M个像素单元，该N×M个像素单元用于接收不同方向的M个指纹光信号以形成M张指纹图像，该N个指纹识别单元中的N个像素单元用于接收一个方向的指纹光信号以形成M张指纹图像中的一张指纹图像，其中，N个像素单元分别属于N个指纹识别单元。
例如，若一个指纹识别单元包括两个像素单元，即上述第一像素单元和第二像素单元，则N个指纹识别单元中N个第一像素单元用于接收第一方 向的指纹光信号，用于形成第一指纹图像，N个指纹识别单元中N个第二像素单元用于接收第二方向的指纹光信号，用于形成第二指纹图像，指纹识别装置共接收两个方向指纹光信号，分别用于形成两张指纹图像。
基于上述图5a中的一个指纹识别单元301的结构，图8a和图8b示出了两种多个指纹识别单元301中多个第一像素单元和多个第二像素单元的排列示意图。在图8a和图8b中，数字“1”表示第一像素单元，数字“2”表示第二像素单元。
如图8a所示，一个指纹识别单元中的第一像素单元和第二像素单元为一个像素单元组，多个指纹识别单元中多个像素单元组交错排列，多个像素单元组形成的像素阵列不是方形阵列排列的像素阵列。
如图8b所示，多个指纹识别单元中的多个像素单元呈方形阵列排列，但相邻的两个第一像素单元之间穿插一个第二像素单元，相邻的两个第二像素单元之间穿插一个第一像素单元，多个第一像素单元和多个第二像素单元交替穿插排列。
不论是上述图8a中的排列方式，或者是图8b中的排列方式，多个第一像素单元的排列方式与其对应的多个圆形微透镜的排列方式相同，均呈密排排列方式，一个第一像素单元与六个第一像素单元相邻，且该六个第一像素单元的中心的连线呈正六边形。同样的，多个第二像素单元的排列方式与其对应的多个圆形微透镜的排列方式也相同，均呈密排排列方式，一个第二像素单元与六个第二像素单元相邻，且该六个第二像素单元的中心的连线呈正六边形。
基于上述图7a中的一个指纹识别单元301的结构，图9示出了多个指纹识别单元301中多个第一像素单元、多个第二像素单元、多个第三像素单元以及多个第四像素单元的排列示意图。在图9中，数字“1”表示第一像素单元，数字“2”表示第二像素单元，数字“3”表示第三像素单元，数字“4”表示第四像素单元。
如图9所示，多个指纹识别单元中的多个像素单元呈方形阵列排列，多个第一像素单元之间、多个第二像素单元之间、多个第三像素单元之间、以及多个第四像素单元之间彼此均不相邻。
同样的，在图9中，多个第一像素单元、多个第二像素单元、多个第三像素单元以及多个第四像素单元的排列方式均与对应的多个圆形微透镜的 排列方式相同，均呈密排排列方式。
综上，不论一个指纹识别单元中包括几个像素单元，对于N个指纹识别单元，接收相同方向的N个像素单元的排列方式与N个圆形微透镜的排列方式相同，不是呈方形阵列排列，而是呈密排排列。
由于接收相同方向的N个像素单元的排列方式不是方形阵列排列，而是密排排列，因此，N个像素单元的像素值的数据结构为密排排列的数据结构，不同于所需要形成的指纹图像中方形阵列排列的数据结构。需要对N个像素单元的像素值进行处理，才能将密排排列的数据结构转换为方形阵列排列的数据结构，形成正常的指纹图像。
可选地，在本申请实施例中，指纹识别装置300还包括处理单元，该处理单元可以为处理器，该处理器可以为指纹识别装置300中的处理器，例如微控制单元(Microcontroller Unit，MCU)等等。该处理器还可以为所述指纹识别装置300所在的电子设备中的处理器，例如手机中主控芯片等，本申请实施例对此不做限定。
该处理器用于对接收相同方向的N个像素单元的像素值进行插值处理，将密排排列的数据结构转换为方形阵列排列的数据结构，得到像素值方形排列的指纹图像。
以上文中，一个指纹识别单元301中的第一像素单元331为例，N个指纹识别单元中包括N个第一像素单元331，该N个第一像素单元331接收的指纹光信号用于形成一张指纹图像。
可选地，图10中示出了一种多个第一像素单元331的原始像素值的数据结构，该图10中第一像素单元331的结构可以与图8a中第一像素单元331的结构相同。其中，字母“X”表示第一像素单元输出的原始像素值。
将图10中密排排列的数据结构进行插值处理后，可以形成图11中的方形阵列排列的数据结构，图11中字母y表示插值处理后形成的插值像素。
可选地，可以将图10中相邻的W个原始像素值进行平均，作为一个插值像素，插入至W个原始像素值之间，其中，W为大于1的正整数。
在一种可能的实施方式中，W＝2，图11中的插值像素y 2可以由原始像素x 1和x 6平均得到，或者也可以由原始像素x 3和x 4平均得到，同样的，每一个插值像素可以由其上下两个原始像素值平均得到或者由其左右两个原始像素值平均得到。在第一像素单元形成的原始像素值数据结构中，每列原 始像素值中相邻两个原始像素值之间，插入该相邻两个原始像素值的平均值。或者间隔的两列原始像素值中，位于同一行的相邻的两个原始像素值之间，插入该相邻的两个原始像素值的平均值。
在另一种可能的实施方式中，W＝4，图11中的插值像素y 2可以由原始像素x 1、x 3、x 4和x 6平均得到，同样的，每一个插值像素可以由其上下左右四个原始像素值平均得到，在第一像素单元形成的原始像素值数据结构中，相邻的4个原始像素值的均值可以插入至该4个原始像素值的中心。
可选地，图12中示出了另一种多个第一像素单元331的原始像素值的数据结构，该图12中的第一像素单元331可以与图8b或者图9中的第一像素单元331的结构相同。其中，字母“x”表示第一像素单元输出的原始像素值。
将图12中密排排列的数据结构进行插值处理后，可以形成图13中的方形阵列排列的数据结构，图13中的字母y表示插值处理后形成的插值像素。
可选地，可以将图12中相邻的W个原始像素值进行平均，作为一个插值像素，插入至W个原始像素值之间，其中，W为大于1的正整数。
在一种可能的实施方式中，W＝2，图13中的插值像素y 3可以由原始像素x 2和x 3平均得到，或者，也可以由原始像素x 1和x 4平均得到，同样的，每一个插值像素可以由其上下两个原始像素值平均得到或者由其左右两个原始像素值平均得到。在第一像素单元形成的原始像素值数据结构中，每列原始像素值中相邻两个原始像素值之间，插入该相邻两个原始像素值的平均值，或者每行原始像素值中相邻两个原始像素值之间，插入该相邻两个原始像素值的平均值。
在另一种可能的实施方式中，W＝4，图13中的插值像素y 3可以由原始像素x 1、x 2、x 3和x 4平均得到，同样的，每一个插值像素可以由其上下左右四个原始像素值平均得到，在第一像素单元形成的原始像素值数据结构中，相邻的4个原始像素值的均值可以插入至该4个像素值的中心。
应理解，W除了可以为2或者为4以外，还可以为其它大于1的正整数，例如，W也可以等于3，例如，图10中的x 1、x 3和x 4的均值也可以作为一个插值像素插入至x 3和x 4之间。图12中的x 1、x 2和x 3的均值也可以作为一个插值像素插入至x 2和x 3之间。
还应理解，除了上述插值方式以外，还可以采用其他的插值方式对多个 第一像素单元的原始像素值进行处理，例如，可以将相邻的多个原始像素值的中值或者从多个原始像素中选择一个原始像素值作为插值像素，旨在将密排排列的数据结构处理为方形阵列排列的数据结构即可，本申请实施例对具体的插值方式不做具体限定。
以上，以指纹识别装置中的多个第一像素单元为例，说明了多个第一像素单元的像素值插值过程，应理解，指纹识别装置中接收其它同一方向的目标指纹光信号的多个像素单元，例如多个第二像素单元，多个第三像素单元或者多个第四像素单元的像素插值过程可以参考上述多个第一像素单元的像素插值过程，此处不再赘述。
在本申请实施例中，接收一个方向的指纹光信号的N个像素单元的像素值经过上述插值过程可以形成一张像素值方形排列的指纹图像，则指纹识别装置中M组N个像素单元经过上述插值过程可以形成M张像素值方形排列的指纹图像。
在图3所示的指纹识别装置200中，微透镜阵列210中多个圆形微透镜呈方形阵列排列，该指纹识别装置200在X方向和Y方向上，空间采样率相同，均为一个圆形微透镜的直径。即，微透镜阵列210在X方向和Y方向上的重复周期相同。
但本申请实施例中，指纹识别装置300中的N个圆形微透镜密排排列，该指纹识别装置300在X方向和Y方向上，空间采样率不同。
例如，如图4所示，在X方向上，指纹识别装置300的空间采样率为相邻两个圆形微透镜的圆心距离D，若圆形微透镜的半径为R，则指纹识别装置在X方向上的空间采样率为2R。在Y方向上，指纹识别装置的空间采样率为
Figure PCTCN2020073901-appb-000004
指纹识别装置300在X方向上的空间采样率大于Y方向上的空间采样率。
可选地，在本申请实施例中，指纹识别装置300的空间采样率小于75μm，即相邻两个圆形微透镜的圆心距离小于75μm。在图4的实施方式中，相邻两个圆形微透镜相切，则圆形微透镜的半径小于37.5μm。
因而，在此情况下，经过上述插值过程形成的像素值方形排列的M张指纹图像在X方向上的空间采样率为R，在Y方向上的空间采样率为
Figure PCTCN2020073901-appb-000005
该M张指纹图像不是真实的指纹图像，而是变形的指纹图像，需要将该M张指纹图像进行进一步的优化处理，调整其横纵比，得到真实的M张优化 指纹图像。
具体地，可以通过对插值后的指纹图像进行上采样或者下采样，调整指纹图像的横纵比从而形成真实的优化指纹图像。
可选地，若上述插值后，形成的指纹图像为A×B像素大小的指纹图像，A为X方向上的像素数量，B为Y方向上的像素数量，将该A×B像素大小的指纹图像调整横纵比后，得到的真实指纹图像为A’×B’像素大小的优化指纹图像，A’为X方向上的像素数量，B’为Y方向上的像素数量。
其中，
Figure PCTCN2020073901-appb-000006
B＝B’，即将A×B像素大小的指纹图像在X方向上进行
Figure PCTCN2020073901-appb-000007
倍的上采样，使得优化的指纹图像在X方向上的像素数增大
Figure PCTCN2020073901-appb-000008
倍，而Y方向上的像素数量不变。
或者，A＝A’，
Figure PCTCN2020073901-appb-000009
即将A×B像素大小的指纹图像在Y方向上进行
Figure PCTCN2020073901-appb-000010
倍的下采样，使得优化的指纹图像在Y方向上的像素数减少为之前的
Figure PCTCN2020073901-appb-000011
而X方向上的像素数量不变。
经过上述插值处理以及横纵比调整之后，得到真实的M张优化指纹图像后，该M张优化指纹图像的一张或者多张可以单独用于进行指纹识别。
可选地，处理单元可以对M张优化指纹图像中的多张优化指纹图像进行重构，形成目标重构图像，该目标重构图像用于进行指纹识别。在本申请实施例中，该重构图像为多张优化指纹图像的叠加后形成的图像，该重构图像的像素数量为多张优化指纹图像的像素数量之和。
下面，以两张优化指纹图像为例，说明将两张优化指纹图像进行重构，形成一张第一目标重构图像的过程。
在一种可能的实施方式中，处理单元将两张优化指纹图像进行叠加，形成重构图像，处理单元可以根据重构图像的质量参数，通过算法调整两张优化指纹图像的移动距离，以形成第一目标重构图像。
具体地，上述重构图像的质量参数包括但不限于：重构图像的对比度、重构图像清晰程度，重构图像的信噪比或者重构图像与两张图像的相似度。
可选地，调整两张图像的移动距离可以为调整两张优化指纹图像移动图像像素点的数量。当该两张优化指纹图像的移动距离为N个图像像素点的距离时，可以根据重构图像的质量参数，调整所述N，以形成第一目标重构图像。
由于显示屏的厚度一定，且显示屏与指纹识别装置的相对位置基本不 变，因此可以测试得到两个图像重构为目标重构图像的所需移动的图像像素点数量，并将该图像像素点数量确定为移动图像参数，将该移动图像参数存储在存储单元中。进而，在后续指纹采集过程中，可以基于该移动图像参数重构出清晰图像。
此外，当安装有指纹识别装置的电子设备被用户使用，在遇到强烈的冲击，指纹识别装置与显示屏的安装距离发生变化或者在量产过程中，指纹识别装置与显示屏之间安装距离波动变化时，两张优化指纹图像移动的图像像素距离发生变化，此时，可以自动校准在安装距离变化情况下的两张优化指纹图像移动的图像像素的距离，进而保证重构后的图像的清晰度，信噪比以及对比度，从而保证指纹识别装置的指纹识别效果，提高用户体验。
换言之，如果指纹模组相对于显示屏的位置发生偏移，可以重新确定每一幅优化指纹图像要移动的图像像素的距离。还可以通过评估图像的质量低于预设阈值或者加速度计测量的数值超过预设阈值时，确定指纹模组相对于显示屏的位置已经发生偏移。
此外，还可以通过对比重构后的图像的中心区域与单幅图像的重叠区域的相似度，二次判断重构后的图像的清晰度是否达到最优状态。
在另一种可能的实施方式中，两张优化指纹图像分别为第一优化指纹图像和第二优化指纹图像，处理单元获取第一优化指纹图像中的第一区域，该第一区域可以为第一优化指纹图像的中心区域或者其它任意区域，本申请实施例对区域的位置和大小不做限定。
然后，处理单元根据该第一区域的像素值，在第二优化指纹图像中确定与该第一区域最接近的第二区域。
具体地，可以对该第一区域中的像素值进行特征提取，例如，提取出高频特征等图像特征，在第二优化指纹图像中进行搜索，得到与该第一区域的特征最为接近的第二区域。
在本申请实施例中，第一优化指纹图像中的第一区域和第二优化指纹图像中的第二区域可以为基于相同的手指区域进行成像的图像区域，该第一区域和第二区域的图像相同或者高度近似，该第一区域和第二区域的形状大小可以相同。
得到与第一区域最相近的第二区域后，计算该第一区域的坐标与该第二区域的坐标之差，移动该第一优化指纹图像与该第二优化指纹图像以形成第 一重构图像；
具体地，第一区域的坐标可以为第一区域的中心点坐标，同样的，第二区域的坐标也可以为第二区域的中心点坐标。当然，第一区域的坐标和第二区域的坐标还可以分别为其左上角坐标等等，本申请实施例对此不做限定。
例如，第一区域的中心点坐标在第一优化指纹图像中的坐标为(X 1，Y 1)，第二区域的中心点坐标在第二优化指纹图像中的坐标为(X 2，Y 2)，第一优化指纹图像和第二优化指纹图像的大小相同，将第一区域的中心点坐标与第二区域的中心点坐标相减得到(△X，△Y)，其中，△X＝X 1-X 2，△Y＝Y 1-Y 2。
根据该(△X，△Y)，将第一优化指纹图像和第二优化指纹图像进行像素移动得到第一目标重构图像，例如，根据该(△X，△Y)，将第一优化图像移动对应的△X，△Y个像素，然后将第二优化图像与第一优化图像的像素进行相互穿插，得到第一目标重构图像。
具体地，第一目标重构图像中，第一区域和第二区域融合为一个目标区域，该目标区域的像素数量为第一区域和第二区域的像素数量之和。且第一目标重构图像的像素数量为第一优化指纹图像和第二优化指纹图像的像素数量之和。
通过上述两种实施方式的说明，可以得到两张优化指纹图像形成第一目标重构图像，若指纹识别单元中的像素数量大于2个，指纹识别装置形成2张以上的优化指纹图像时，其它优化指纹图像也可以按照上述方法进行重构，以形成多张优化指纹图像重构在一起的目标指纹重构图像，该目标指纹重构图像用于进行指纹识别。
例如，若指纹识别单元中的像素数量为4个时，指纹识别装置形成4张优化指纹图像，可以将4张优化指纹图像分为2组，每组两张优化指纹图像可以按照上述方式进行重构得到一张第一目标重构图像，然后将两张第一目标重构图像再次进行重构，可以得到最终的目标重构图像。
采用重构图像进行指纹识别，使得指纹识别装置具有大的视场，能够进一步提高指纹识别装置的性能。
以上，结合图4至图13详细说明了本申请实施例中指纹识别装置300的基本结构以及进行指纹图像处理的过程，下文，将结合图14至图21将对指纹识别装置300中N个指纹识别单元301中每个指纹识别单元301的结构进行详细说明。
可选地，指纹识别单元301中M个像素单元接收的M个方向的目标指纹光信号均为相对于显示屏倾斜的光信号，或者M个方向的目标指纹光信号中一个目标指纹光信号为垂直于显示屏倾斜的光信号，其它的M-1个目标指纹光信号为倾斜于显示屏的光信号。
换言之，在指纹识别单元301中，至少两层挡光层中形成的M个不同方向的导光通道的方向均为相对于显示屏倾斜的方向。或者，M个不同方向的导光通道中一个导光通道的方向为垂直于显示屏的方向，其它的M-1个导光通道的方向为相对于显示屏倾斜的方向。
可选地，上述M个方向的目标指纹光信号的角度(目标指纹光信号与垂直于显示屏的方向的夹角)可以在0°至60°之间。或者说，圆形微透镜310接收的指纹光信号的角度也可以在0°至60°之间。
即至少两层挡光层中形成的M个不同方向的导光通道与垂直于显示屏方向的夹角也可以在0°至60°之间，或者说，至少两层挡光层中形成的M个不同方向的导光通道与显示屏的夹角可以在30°至90°之间，若显示屏与指纹识别单元301中的M个像素单元所在平面平行设置，则至少两层挡光层中形成的M个不同方向的导光通道分别与M个像素单元所在平面的夹角可以在30°至90°之间。
可选地，上述M个不同方向的导光通道与显示屏的夹角可以相同。
在本申请的一些实施例中，至少两层挡光层中的底层挡光层设置有与M个像素单元分别对应的M个通光小孔。
下面，以指纹识别单元301包括两个像素单元为例，详细介绍该指纹识别单元301的结构。
图14示出了图5中的指纹识别单元的一种示意性俯视图。图15是图14中指纹识别单元沿A-A’方向的截面示意图。
如图5、图14和图15所示，指纹识别单元中包括两层挡光层，两层挡光层中的顶层挡光层上设置第一通光小孔3211，两层挡光层中的底层挡光层上设置对应于第一像素单元331的第二通光小孔3221以及对应于第二像素单元332的第三通光小孔3222。
可选地，若至少两层挡光层为多于两层的多层挡光层，则多层挡光层中的导光通道的方向可以为导光通道中最上层通光小孔的中心与最下层通光小孔的中心连线方向。或者导光通道的方向为与该中心连线方向相近的方 向，例如，导光通道的方向与中心连线的方向在±5°之内。
例如，图15中，第一像素单元331对应的第一导光通道的方向为第一通光小孔3211与第二通光小孔3221的连线方向或者为与该连线方向相近的方向，第二像素单元331对应的第二导光通道的方向为第一通光小孔3211与第三通光小孔3222的连线方向或者为与该连线方向相近的方向。
如图15所示，第一目标指纹光信号311通过第一通光小孔3211以及第二通光小孔3221构成的第一导光通道被第一像素单元中的第一感光区域3311接收，第二目标指纹光信号312通过第一通光小孔3211以及第三通光小孔3222构成的第二导光通道被第二像素单元中的第二感光区域3321接收。
可选地，在本申请实施例中，第一感光区域3311的中心至微透镜310中心的距离和第二感光区域3321的中心至微透镜310中心的距离相等。
可选地，在该情况下，第一感光区域3311接收的第一目标指纹光信号311与第二感光区域3321接收的第二目标指纹光信号312与显示屏的夹角相同，或者说，第一感光区域3311对应的第一导光通道与显示屏的夹角和第二感光区域3321对应的第二导光通道与显示屏的夹角相等。
此外，第一感光区域3311的中心至微透镜310中心的距离和第二感光区域3321的中心至微透镜310中心的距离也可以不相等。
在该情况下，第一感光区域3311接收的第一目标指纹光信号311与第二感光区域3321接收的第二目标指纹光信号312与显示屏的夹角不相同，或者说，第一感光区域3311对应的第一导光通道与显示屏的夹角和第二感光区域3321对应的第二导光通道与显示屏的夹角不相等。
可选地，该至少两层挡光层还可以为三层挡光层，例如，在上述申请实施例中的两层挡光层中再设置一层挡光层，该挡光层中同样设置与第一像素单元331以及第二像素单元332对应的通光小孔，形成该两个像素单元对应的两个导光通道。
若至少两层挡光层为三层以及三层以上的挡光层，则底层挡光层与顶层挡光层之间的挡光层为中间挡光层，两个导光通道中，底层挡光层与顶层挡光层的通光小孔的连线方向为导光通道的方向，该中间挡光层中通光小孔的中心可以分别位于两个导光通道的连线上。
可选地，至少两层挡光层中的底层挡光层为两个像素单元表面的金属布 线层。
例如，第一像素单元331和第二像素单元332的金属布线层设置在微透镜310的后焦平面位置，该金属布线层为至少两层挡光层的底层挡光层，且在第一像素单元331和第二像素单元332的感光区域的上方分别形成有第二通光小孔3221和第三通光小孔3222。
换言之，通过在指纹传感器芯片的金属布线层上，形成至少两层挡光层中的底层挡光层，并在每一个像素单元的感光区域上方形成对应的通光小孔。或者说，可以将指纹传感器芯片的金属布线层复用于微透镜和像素单元之间的光路层。
可选地，至少两层挡光层的顶层挡光层设置有与第一像素单元331和第二像素单元332对应的至少一个通光小孔。例如，顶层挡光层中可为第一像素单元331和第二像素单元332分别设置一个通光小孔，又例如，顶层挡光层中也可为第一像素单元331和第二像素单元332共同设置一个通光小孔，例如上述的第一通光小孔3211，换言之，第一像素单元321对应的第一导光通道和第二像素单元322对应的第二导光通道在至少两层挡光层的顶层挡光层中的通光小孔重合。
可选地，上述第一导光通道和第二导光通道中的通光小孔由上至下孔径依次减小，例如上述第二通光小孔3221以及第三通光小孔3222的孔径均小于第一通光小孔3211的孔径。
换言之，上方的挡光层中的通光小孔的孔径设置的大于下方的挡光层中的通光小孔的孔径，由此。可以使得至少两层挡光层可以引导较多(一定的角度范围)的光信号至相应的像素单元。
图16示出了另一种指纹识别单元301的示意性俯视图，图17示出了图12中指纹识别单元301沿A-A’方向的截面示意图。
如图16和图17所示，该指纹识别单元301包括三层挡光层。其中，顶层挡光层中设置上述第一通光小孔3211，底层挡光层中设置上述第二通光小孔3221和上述第三通光小孔3222。此外，新增的中间层挡光层中设置有第四通光小孔3231和第五通光小孔3232。其中，第一通光小孔3221、第四通光小孔3231以及第二通光小孔3221形成第一感光区域3311单元对应的第一导光通道，该三个通光小孔的中心可以位于同一直线上。此外，第一通光小孔3221、第五通光小孔3232以及第三通光小孔3222形成第二感光区域 3321对应的第二导光通道，该三个通光小孔的中心也可以位于同一直线上。
可选地，在本申请实施例中，第一通光小孔3221的孔径大于第四通光小孔3231和第五通光小孔3232的孔径，且第四通光小孔3231和第五通光小孔3232的孔径大于第二通光小孔3221和第三通光小孔3222的孔径。
应理解，在本申请中，指纹识别单元301还可以包括更多层的挡光层，下文中均以两层挡光层作为示意进行说明，两层以上的多层挡光层的情况可以参考相关说明，此处不再赘述。
如图14和图16所示，该第一像素单元331和第二像素单元332所在区域(为了便于描述，在本申请实施例中，第一像素单元331和第二像素单元332的所在区域简称为像素区域330)可以位于圆形微透镜310的正下方，像素区域330的中心与微透镜310的中心在垂直方向上重合。其中，第一像素单元331和第二像素单元332均接收倾斜方向的目标指纹光信号，即第一像素单元331对应的第一导光通道和第二像素单元332对应的第二导光通道的方向均相对于显示屏倾斜。
其中，第一像素单元331和第二像素单元332中均包括感光区域(Active Area，AA)，用于分别接收经过两个导光通道的第一目标指纹光信号和第二目标指纹光信号并转换为对应的电信号。
可选地，该感光区域可以为四边形区域，例如，其可以为正方形区域或者长方形区域。
该感光区域可以为像素单元中光电二极管所在的区域，即像素单元中接收光信号的区域，像素单元中的其它区域可以用于设置像素单元中的其它电路以及用于像素间走线的排布。可选地，该感光区域对于蓝光、绿光、红光或红外光的光灵敏度大于第一预定阈值，量子效率大于第二预定阈值。例如，该第一预定阈值可以为0.5v/lux-sec，该第二预定阈值可以为40％。也就是说，该感光区域对于蓝光(波长为460±30nm)、绿光(波长为540±30nm)、红光或红外光(波长≥610nm)具有较高的光灵敏度和较高的量子效率，以便于检测相应的光。
第一像素单元331的第一感光区域3311位于第二通光小孔3221的下方，即位于第一导光通道的底部，用于接收第一目标指纹光信号，第二像素单元332的第二感光区域3321位于第三通光小孔3222的下方，即位于第二导光通道的底部，用于接收第二目标指纹光信号。
如图14和图16所示，第一像素单元331和第二像素单元332组成的像素区域330为四边形的像素区域，该第一感光区域3311和第二感光区域3321可以位于像素区域330的对角线上。在此情况下，第一感光区域3311接收的第一目标指纹光信号与第二感光区域3321接收的第二目标指纹光信号在像素区域330所在平面的投影的夹角呈180°夹角，或者说，第一导光通道在像素区域330所在平面的投影与第二导光通道在像素区域330所在平面的投影呈180°夹角。
可选地，如图18所示，第一感光区域3311接收的第一目标指纹光信号与第二感光区域3321接收的第二目标指纹光信号在像素区域330所在平面的投影的夹角呈90°夹角，或者说，第一导光通道在像素区域330所在平面的投影与第二导光通道在像素区域330所在平面的投影呈90°夹角。
采用本申请实施例的方案，两个像素单元接收的指纹光信号相互垂直，便于采集到的垂直于指纹中脊和谷纹路的指纹光信号，能够提高指纹识别单元接收的指纹光信号的质量，从而提高指纹图像质量，提升指纹识别装置的指纹识别性能。
上述图14、图16和图18仅举例说明了几种指纹识别单元301的俯视示意图，其中第一导光通道和第二导光通道在像素区域330所在平面的投影呈180°夹角或者90°夹角，应理解，第一导光通道和第二导光通道在像素区域330所在平面的投影可以呈0°至180°之间的任意夹角，本申请实施例对此不作任何限定。
还应理解，第一导光通道和第二导光通道在像素区域330所在平面的投影呈180°夹角或者呈90°夹角的实现方式不仅限于上述图14、图16和图18所示的指纹识别单元，其它实现第一导光通道和第二导光通道在像素区域330所在平面的投影呈180°夹角或者呈90°夹角的结构也在本申请的保护范围之内。
在本申请实施例中，可以通过像素单元、像素单元中的感光区域的设置，调整其对应的导光通道方向，使其满足设计的光路需求。
在一种可能的实施方式中，参见上述图14、图16和图18，两个像素单元中的感光区域只占据像素单元中的小部分区域，以满足接收光信号的要求。
在该申请实施例方式中，第一感光区域3311的中心可以位于第一导光 通道的底部，且第二感光区域3321的中心可以位于第二导光通道的底部。换言之，第一感光区域3311的中心位于第一通光小孔3211与第二通光小孔3221的连线上，第二感光区域3321的中心位于第一通光小孔3211与第三通光小孔3222的连线上。
通过上述设置，第一目标指纹光信号通过第一导光通道在第一像素单元331上形成第一光斑3301，第二目标指纹光信号通过第二导光通道在第二像素单元332上形成第二光斑3302。
为了最大化的接收第一目标指纹光信号和第二目标指纹光信号，可选地，第一像素单元331上的第一感光区域3311可以完全覆盖上述第一光斑3301，第二像素单元332上的第二感光区域3321可以完全覆盖上述第二光斑3302。
可选地，第一像素单元为四边形区域，其长和宽分别为L和W，其中，W≤L，W和L均为正数，第一像素单元中的第一感光区域的长和宽均大于等于0.1×W。当然，第二像素单元及其第二感光区域的尺寸也可以对应满足上述条件。
在一种可能的实施方式中，如图14、图16和图18所示，该第一感光区域3311为四边形区域且外切于该第一光斑3301，类似地，该第二感光区域3321为四边形区域且外切于该第二光斑3302。
在此情况下，像素单元中的感光区域较小，但充分接收了经过导光通道后的指纹光信号，满足指纹成像要求，且与此同时，像素单元中的其它区域面积较大，给像素单元的布线提供了足够的空间，降低了工艺要求，提高了工艺制造的效率，且其它区域可以用于设置其它的电路结构，能够提高像素单元的信号处理能力。
应理解，当两个像素单元中的感光区域只占据像素单元中的小部分区域时，感光区域的中心还可以不位于导光通道的底部，而发生一定的偏移，此时，可以扩大感光区域的面积，使得感光区域能够覆盖指纹光信号在像素单元上的光斑的全部面积。
可选地，在图14、图16和图18中，第一像素单元331和第二像素单元332为长方形像素单元，第一感光区域3311和第二感光区域3321偏移于两个像素单元的中心设置。由于第一像素单元331和第二像素单元332均接收倾斜方向的光信号，且倾斜角度越大，则像素单元中的感光区域距离微透镜 的中心距离越远。因而，第一感光区域3311和第二感光区域3321除了偏移于像素单元的中心设置外，还向远离于微透镜中心的方向偏移，能够增大两个感光区域接收的目标指纹光信号角度，从而减小指纹识别单元的厚度。
应理解，在本申请实施例中，第一感光区域3311和第二感光区域3321也可以位于第一像素单元331和第二像素单元332的中心，为了满足感光区域接收光信号的角度需求，可以将第一像素单元331和第二像素单元332向远离于微透镜中心的方向偏移，增大两个感光区域接收的目标指纹光信号角度，减小指纹识别单元的厚度。
在本申请实施例中，两个感光区域可以设置于像素单元中的任意位置，旨在接收经过两个通道的目标指纹光信号，本申请实施例对两个感光区域在像素单元中的具体位置不做任何限定。
在一种可能的实施方式中，两个像素单元中的感光区域占据像素单元中的大部分区域，以提高像素单元的动态范围。
可选地，图19示出了指纹识别单元301的另一种示意性俯视图。
如图19所示，两个像素单元中的感光区域面积较大，除了覆盖像素单元上光斑外，还覆盖了其它区域。在图19中，两个像素单元中的感光区域占据了像素单元的大部分面积。例如，第一像素单元331中的第一感光区域3311占据了第一像素单元331中的95％以上的面积，和/或第二像素单元332中的第二感光区域3321占据了第二像素单元332中的95％以上的面积。
在该实施方式下，像素单元的感光区域增大，能够提高像素单元的满阱容量以及像素单元的动态范围(Dynamic Range)，从而提升像素单元的整体性能，实现指纹识别装置的高动态范围成像(High Dynamic Range Imaging，HDR)。
上述图14至图19中的实施例仅示出了像素区域330的中心与圆形微透镜的中心在垂直方向上重合的情况下，部分指纹识别单元301的俯视示意图，第一像素单元和第二像素单元中感光区域可以分别设置于像素单元中的任意区域，以实现接收不同角度的目标指纹光信号。
应理解，像素区域330的中心与圆形微透镜的中心在垂直方向上还可以不重合，例如，在上述包括第一像素单元331和第二像素单元332的指纹识别单元中，第一像素单元331和第二像素单元332在空间位置上位于圆形微透镜310的斜下方，第一像素单元和第二像素单元中感光区域同样可以分别 设置于像素单元中的任意区域。
以上，结合图14至图19，以指纹识别单元中包括两个像素单元为例进行了详细说明，应理解，若指纹识别单元中包括两个以上的像素单元时，其中的两个像素单元及对应的导光通道可以参考以上描述。
图20和图21示出了图7中指纹识别单元301的两种示意性俯视图，该指纹识别单元301中包括四个像素单元。
如图20所示，该第一像素单元331、第二像素单元332、第三像素单元333和第四像素单元334所在区域(为了便于描述，在下文中，该四个像素单元所在区域简称为像素区域330)可以位于圆形微透镜310斜下方，像素区域330的中心与圆形微透镜310的中心在垂直方向上不重合。
如图21所示，四个像素单元所在区域也可以位于圆形微透镜310的下方，像素区域330的中心与圆形微透镜310的中心在垂直方向上重合。
可选地，四个像素单元中至少三个像素单元接收倾斜方向的目标指纹光信号，换言之，四个像素单元均接收倾斜方向的目标指纹光信号，即四个像素单元对应的四个导光通道的方向均相对于显示屏倾斜。或者，四个像素单元中三个像素单元接收倾斜方向的目标指纹光信号，另一个像素单元接收垂直方向的目标指纹光信号。
同样的，四个像素单元中均包括感光区域，用于分别接收经过四个导光通道的四个目标指纹光信号并转换为对应的电信号。第一像素单元331的第一感光区域3311位于第二通光小孔3221的下方，即位于第一导光通道的底部，用于接收第一目标指纹光信号；第二像素单元332的第二感光区域3321位于第三通光小孔3222的下方，即位于第二导光通道的底部，用于接收第二目标指纹光信号；第三像素单元333的第三感光区域3331位于第四通光小孔3223的下方，即位于第三导光通道的底部，用于接收第三目标指纹光信号，第四像素单元334的第四感光区域3341位于第五通光小孔3224的下方，即位于第四导光通道的底部，用于接收第四目标指纹光信号。
在本申请实施例中，四个感光区域接收的指纹光信号与显示屏的夹角可以部分相同，或者全部相同，或者全部不相同，本申请实施例对此不做限定。
可选地，在本申请实施例中，指纹识别单元同样包括三层挡光层，或者包括更多层的挡光层，两层以上的多层挡光层的情况可以参考以上相关说明，此处不再赘述。
参见图20和图21，在一种可能的实施方式中，四个像素单元中的感光区域只占据像素单元中的小部分区域，以满足接收光信号的要求。
在该申请实施例方式中，第一感光区域3311的中心可以位于第一导光通道的底部，换言之，第一感光区域3311的中心可以位于第一通光小孔3211与第二通光小孔3221的连线上。同样的，其它像素单元中的感光区域的中心同样可以位于其对应的导光通道的底部。
通过上述设置，第一目标指纹光信号通过第一导光通道在第一像素单元331上形成第一光斑3301，第二目标指纹光信号通过第二导光通道在第二像素单元332上形成第二光斑3302，第三目标指纹光信号通过第三导光通道在第三像素单元333上形成第三光斑3303，第四目标指纹光信号通过第四导光通道在第四像素单元334上形成第三光斑3304。
为了最大化的接收第一目标指纹光信号、第二目标指纹光信号、第三目标指纹光信号以及第四目标指纹光信号，可选地，第一像素单元331上的第一感光区域3311可以完全覆盖上述第一光斑3301，第二像素单元332上的第二感光区域3321可以完全覆盖上述第二光斑3302，第三像素单元333上的第三感光区域3331可以完全覆盖上述第三光斑3303，并且第四像素单元334上的第四感光区域3331可以完全覆盖上述第四光斑3304。
可选地，四个像素单元中，第一像素单元331可以为四边形区域，其长和宽分别为L和W，其中，W≤L，W和L均为正数，第一像素单元331中的第一感光区域3311的长和宽均大于等于0.1×W。当然，四个像素单元中其它三个像素单元和感光区域的尺寸也可以对应满足上述条件。
在一种可能的实施方式中，如图20所示，四个像素单元中的感光区域为四边形区域且外切于该感光区域。
在此情况下，像素单元中的感光区域较小，但充分接收了经过导光通道后的指纹光信号，满足指纹成像要求，且与此同时，像素单元中的其它区域面积较大，给像素单元的布线提供了足够的空间，降低了工艺要求，提高了工艺制造的效率，且其它区域可以用于设置其它的电路结构，能够提高像素单元的信号处理能力。
应理解，当四个像素单元中的感光区域只占据像素单元中的小部分区域时，感光区域的中心还可以不位于导光通道的底部，而发生一定的偏移，此时，可以扩大感光区域的面积，使得感光区域能够覆盖指纹光信号在像素单 元上的光斑的全部面积。
可选地，在图20和图21中，四个像素单元均为大小相同的四边形像素单元。
应理解，在本申请实施例中，除上述图中所示的像素分布外，四个像素单元的形状大小以及相对位置可以任意设置，四个像素的形状大小可以相同也可以不相同，本申请实施例对此不做任何限定。例如，四个像素单元的第一像素单元和第三像素单元为正方形像素，而第二像素单元为长方形像素，或者四个像素单元均为正方形像素等等。
可选地，在本申请实施例中，四个感光区域可以偏移于四个像素单元的中心设置。由于四个感光区域可以均接收倾斜方向的光信号，且倾斜角度越大，则像素单元中的感光区域距离微透镜的中心距离越远，例如，如图20所示，第三感光区域以及第四感光区域距离微透镜的中心距离较远，而第一感光区域以及第二感光区域距离微透镜的中心距离较近，因而第三感光区域和第四感光区域接收的目标指纹光信号的角度较大，第一感光区域和第二感光区域接收的目标指纹光信号的角度较小。
此外，四个感光区域除了偏移于像素单元的中心设置外，还向远离于微透镜中心的方向偏移，能够增大四个感光区域接收的目标指纹光信号角度，从而进一步减小指纹识别单元的厚度。
应理解，在本申请实施例中，四个感光区域也可以分别位于四个像素单元的中心，为了满足感光区域接收光信号的角度需求，可以将四个像素单元向远离于微透镜中心的方向偏移，增大四个感光区域接收的目标指纹光信号角度，减小指纹识别单元的厚度。
在本申请实施例中，四个像素单元也可以设置于圆形微透镜下方的任意位置，且四个感光区域可以设置于该四个像素单元中的任意位置，旨在接收经过四个通道的目标指纹光信号，本申请实施例对四个像素单元的位置以及四个感光区域在像素单元中的具体位置不做任何限定。
如图21所示，第一感光区域3311接收的第一目标指纹光信号与第二感光区域3321接收的第二目标指纹光信号在像素区域330所在平面的投影的夹角呈+90°，第一感光区域3311接收的第一目标指纹光信号与第三感光区域3331接收的第三目标指纹光信号在像素区域330所在平面的投影的夹角呈-90°，并且，第一感光区域3311接收的第一目标指纹光信号与第四感光 区域3341接收的第四目标指纹光信号在像素区域330所在平面的投影的夹角呈180°。
或者说，第一导光通道在像素区域330所在平面的投影与第二导光通道在像素区域330所在平面的投影呈+90°夹角，第一导光通道在像素区域330所在平面的投影与第三导光通道在像素区域330所在平面的投影呈-90°夹角，并且第一导光通道在像素区域330所在平面的投影与第四导光通道在像素区域330所在平面的投影呈180°夹角。
采用本申请实施例的方案，四个像素单元中多组两个像素单元接收的指纹光信号相互垂直，即其中的第一像素单元与第二像素单元，第一像素单元与第三像素单元，第四像素单元与第二像素单元，以及第四像素单元与第三像素单元接收的指纹光信号相互垂直，在此情况下，便于采集到的垂直于指纹中脊和谷纹路的指纹光信号，能够提高指纹识别单元接收的指纹光信号的质量，从而提高指纹图像质量，提升指纹识别装置的指纹识别性能。
应理解，四个像素单元中任意两个像素单元接收的指纹光信号垂直，即可以采集到的垂直于指纹中脊和谷纹路的指纹光信号，提高指纹识别单元接收的指纹光信号的质量，该四个像素单元中其它两个像素单元接收的指纹光信号的角度本申请实施例对此不做限定。
可选地，基于上述申请实施例中，第一感光区域3311的中心至微透镜310中心的距离、第二感光区域3321的中心至微透镜310中心的距离、第三感光区域3331的中心至微透镜310中心的距离、以及第四感光区域3341的中心至微透镜310中心的距离中任意两个距离可以不相等，或者四个距离均不相等，此时，第一目标指纹光信号、第二目标指纹光信号、第三目标指纹光信号以及第四目标指纹光信号与显示屏的四个夹角中任意两个夹角不相等，或者四个夹角均不相等，或者说，第一导光通道、第二导光通道、第三导光通道以及第四导光通道与显示屏的四个夹角中任意两个夹角不相等，或者四个夹角均不相等。
以上仅举例说明了指纹识别单元301中四个像素单元所在的像素区域330位于圆形微透镜310的下方的两种情况，应理解，像素区域300还可以位于微透镜310下方的任意区域，本申请实施例对此不做任何限定，且四个像素单元中的感光区域可以位于其所在的像素单元中的任意区域，本申请实施例对此也不做任何限定。
应当理解的是，随着像素单元和感光区域的移动，感光区域接收的目标指纹光信号的方向以及感光区域对应的导光通道的方向也随之发生变化，换言之，也可以根据光路设计中，目标指纹光信号需求的方向，设计像素单元、感光区域相对于微透镜的位置。
具体地，在一种可能的光路设计方式中，第一像素单元接收的第一目标指纹光信号的角度大于四个目标指纹光信号中其它三个目标指纹光信号的角度，其中，光信号的角度是指光信号与垂直于显示屏的方向的夹角。
圆形微透镜310与四个像素单元所在平面之间的光路高度h根据以下公式计算：
h＝x×cotθ；
其中，x为接收第一目标指纹光信号的第一感光区域3311的中心与微透镜310的中心在四个像素单元所在平面上的投影点之间的距离，θ为第一目标指纹光信号的角度。
应理解，若指纹识别单元中的像素单元数量为M个时，若M个像素单元中第一像素单元接收的第一目标指纹光信号的角度大于其它M-1个像素单元接收的其它M-1个目标指纹光信号的角度，则圆形微透镜310与M个像素单元所在平面之间的光路高度h同样可以根据上述公式计算得到。
图22是包括多个指纹识别单元的电子设备的示意性结构图。
如图22所示，所述电子设备30可包括显示屏120、位于该显示屏120的下方的滤波片400，以及位于该滤波片400下方的由多个指纹识别单元301构成的指纹识别装置300，其中每一个指纹识别单元301的像素单元，即上述像素阵列302可以设置在基板500的上表面。其中像素阵列302和该基板500可以称为指纹传感器或图像传感器。
可选地，在本申请实施例中，该滤波片400还可以生长于像素阵列302的表面，与像素阵列302集成在指纹传感器或图像传感器中。
具体地，该基板可以为图1中的电路板150，其具体可以电路板(Printed circuit board，PCB)，柔性电路板(Flexible Printed Circuit，FPC)或者软硬结合板等等，本申请实施例对此不做限定。
应理解，附图仅为本申请实施例的示例，不应理解为对本申请的限制。
例如，可替代地，上述指纹识别装置包括的至少一个挡光层包括的挡光层的数量大于3层的挡光层。
又例如，上述指纹识别装置还可以包括图像传感器驱动单元，微程序控制器等器件。
本申请实施例还提供了一种电子设备，该电子设备可以包括显示屏以及上述本申请实施例的指纹识别装置，其中，该指纹识别装置设置于显示屏下方，以实现屏下光学指纹识别。该电子设备可以为任何具有显示屏的电子设备。
其中，显示屏可以采用以上描述中的显示屏，例如OLED显示屏或其他显示屏，显示屏的相关说明可以参考以上描述中关于显示屏的描述，为了简洁，在此不再赘述。
在本申请的一些实施例中，该显示屏的下方可以设置有一层泡棉层，该泡棉层在指纹识别装置的上方可以设置有至少一个开孔，该至少一个开孔用于将经由手指反射的光信号传输至指纹识别装置。
例如，显示屏下方有一层黑色泡棉，该黑色泡棉在指纹识别装置的上方可以设置有一个开孔，当手指放于点亮的显示屏上方时，手指就会反射显示屏发出的光，经由手指反射的反射光会穿透显示屏以及通过至少一个开孔传输至指纹识别装置。指纹是一个漫反射体，其反射光在各方向都存在。
此时，可以使用指纹识别装置中的特定光路，使指纹识别装置中的光学感应像素阵列接收多个方向的倾斜光信号，该指纹识别装置中的处理单元或与该指纹识别装置相连的处理单元通过算法可以获取重构的指纹图像，进而进行指纹识别。
在本申请的一些实施例中，指纹识别装置和显示屏之间可以存在或不存在间隙。
例如，指纹识别装置和显示屏之间可以存在0至1mm的间隙。
在本申请的一些实施例中，指纹识别装置可以将采集的图像输出给计算机专用处理器或者电子设备的专用处理器，进而进行指纹识别。
应理解，本申请实施例的处理器可以是一种集成电路芯片，具有信号的处理能力。在实现过程中，上述方法实施例的各步骤可以通过处理器中的硬件的集成逻辑电路或者软件形式的指令完成。上述的处理器可以是通用处理器、数字信号处理器(Digital Signal Processor，DSP)、专用集成电路(Application Specific Integrated Circuit，ASIC)、现成可编程门阵列(Field Programmable Gate Array，FPGA)或者其他可编程逻辑器件、分立门或者晶 体管逻辑器件、分立硬件组件。可以实现或者执行本申请实施例中的公开的各方法、步骤及逻辑框图。通用处理器可以是微处理器或者该处理器也可以是任何常规的处理器等。结合本申请实施例所公开的方法的步骤可以直接体现为硬件译码处理器执行完成，或者用译码处理器中的硬件及软件模块组合执行完成。软件模块可以位于随机存储器，闪存、只读存储器，可编程只读存储器或者电可擦写可编程存储器、寄存器等本领域成熟的存储介质中。该存储介质位于存储器，处理器读取存储器中的信息，结合其硬件完成上述方法的步骤。
可以理解，本申请实施例的指纹识别还可以包括存储器，存储器可以是易失性存储器或非易失性存储器，或可包括易失性和非易失性存储器两者。其中，非易失性存储器可以是只读存储器(Read-Only Memory，ROM)、可编程只读存储器(Programmable ROM，PROM)、可擦除可编程只读存储器(Erasable PROM，EPROM)、电可擦除可编程只读存储器(Electrically EPROM，EEPROM)或闪存。易失性存储器可以是随机存取存储器(Random Access Memory，RAM)，其用作外部高速缓存。通过示例性但不是限制性说明，许多形式的RAM可用，例如静态随机存取存储器(Static RAM，SRAM)、动态随机存取存储器(Dynamic RAM，DRAM)、同步动态随机存取存储器(Synchronous DRAM，SDRAM)、双倍数据速率同步动态随机存取存储器(Double Data Rate SDRAM，DDR SDRAM)、增强型同步动态随机存取存储器(Enhanced SDRAM，ESDRAM)、同步连接动态随机存取存储器(Synchlink DRAM，SLDRAM)和直接内存总线随机存取存储器(Direct Rambus RAM，DR RAM)。应注意，本文描述的系统和方法的存储器旨在包括但不限于这些和任意其它适合类型的存储器。
本领域普通技术人员可以意识到，结合本文中所公开的实施例描述的各示例的单元及算法步骤，能够以电子硬件、或者计算机软件和电子硬件的结合来实现。这些功能究竟以硬件还是软件方式来执行，取决于技术方案的特定应用和设计约束条件。专业技术人员可以对每个特定的应用来使用不同方法来实现所描述的功能，但是这种实现不应认为超出本申请的范围。
所属领域的技术人员可以清楚地了解到，为描述的方便和简洁，上述描述的系统、装置和单元的具体工作过程，可以参考前述方法实施例中的对应过程，在此不再赘述。
在本申请所提供的几个实施例中，应所述理解到，所揭露的系统、装置和方法，可以通过其它的方式实现。例如，以上所描述的装置实施例仅仅是示意性的，例如，所述单元的划分，仅仅为一种逻辑功能划分，实际实现时可以有另外的划分方式，例如多个单元或组件可以结合或者可以集成到另一个系统，或一些特征可以忽略，或不执行。另一点，所显示或讨论的相互之间的耦合或直接耦合或通信连接可以是通过一些接口，装置或单元的间接耦合或通信连接，可以是电性，机械或其它的形式。
所述作为分离部件说明的单元可以是或者也可以不是物理上分开的，作为单元显示的部件可以是或者也可以不是物理单元，即可以位于一个地方，或者也可以分布到多个网络单元上。可以根据实际的需要选择其中的部分或者全部单元来实现本实施例方案的目的。
另外，在本申请各个实施例中的各功能单元可以集成在一个处理单元中，也可以是各个单元单独物理存在，也可以两个或两个以上单元集成在一个单元中。
所述功能如果以软件功能单元的形式实现并作为独立的产品销售或使用时，可以存储在一个计算机可读取存储介质中。基于这样的理解，本申请的技术方案本质上或者说对现有技术做出贡献的部分或者所述技术方案的部分可以以软件产品的形式体现出来，所述计算机软件产品存储在一个存储介质中，包括若干指令用以使得一台计算机设备(可以是个人计算机，服务器，或者网络设备等)执行本申请各个实施例所述方法的全部或部分步骤。而前述的存储介质包括：U盘、移动硬盘、只读存储器(Read-Only Memory，ROM)、随机存取存储器(Random Access Memory，RAM)、磁碟或者光盘等各种可以存储程序代码的介质。
以上所述，仅为本申请的具体实施方式，但本申请的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本申请揭露的技术范围内，可轻易想到变化或替换，都应涵盖在本申请的保护范围之内。因此，本申请的保护范围应所述以权利要求的保护范围为准。

Claims (30)

  1. 一种指纹识别装置，其特征在于，适用于显示屏的下方以实现屏下光学指纹识别，所述指纹识别装置包括密排排列的N个指纹识别单元，N为正整数；
    所述N个指纹识别单元中的每个指纹识别单元包括：
    圆形微透镜；
    至少两层挡光层，设置在所述圆形微透镜下方，所述至少两层挡光层中的每一层挡光层中设置通光小孔以形成不同方向的M个导光通道，M为大于1的正整数；
    M个像素单元，设置在所述至少两层挡光层下方，所述M个像素单元分别位于所述M个导光通道的底部；
    其中，从所述显示屏上方的手指反射或散射后返回的光信号通过所述圆形微透镜汇聚后，其中不同方向的M个目标指纹光信号分别经过所述M个导光通道传输至所述M个像素单元，所述M个目标指纹光信号用于检测所述手指的指纹信息；
    所述N个指纹识别单元中每个指纹识别单元与六个指纹识别单元相邻，且所述六个指纹识别单元中的六个圆形微透镜的中心的连线构成正六边形。
  2. 根据权利要求1所述的指纹识别装置，其特征在于，所述N个指纹识别单元中包括N×M个像素单元，用于接收不同方向的M个指纹光信号以形成M张指纹图像，所述N个指纹识别单元中的N个像素单元用于接收一个方向的指纹光信号形成N个像素值，所述N个像素值用于形成所述M张指纹图像中的一张指纹图像，其中，所述N个像素单元分别属于N个指纹识别单元；
    所述M张指纹图像中的至少一张指纹图像用于进行指纹识别。
  3. 根据权利要求2所述的指纹识别装置，其特征在于，所述N个像素单元的排列方式与所述N个指纹识别单元中N个圆形微透镜的排列方式相同。
  4. 根据权利要求3所述的指纹识别装置，其特征在于，所述指纹识别装置还包括处理单元；
    所述处理单元用于对所述N个像素单元的N个像素值中每相邻的W个像素值之间插入一个插值像素，以得到一张像素值方形排列的指纹图像，其 中，W为大于1的正整数。
  5. 根据权利要求4所述的指纹识别装置，其特征在于，W＝4，所述插值像素为N个像素值中每相邻的4个像素值的均值。
  6. 根据权利要求2至5中任一项所述的指纹识别装置，其特征在于，所述处理单元用于对所述M张指纹图像进行上采样或者下采样，以调整所述M张指纹图像横纵比，形成M张优化指纹图像。
  7. 根据权利要求6所述的指纹识别装置，其特征在于，所述处理单元用于获取所述M张优化指纹图像中的第一优化指纹图像和第二优化指纹图像，并获取所述第一优化指纹图像中的第一区域；
    根据所述第一区域的像素值，在所述第二优化指纹图像中确定与所述第一区域最接近的第二区域；
    计算所述第一区域的坐标与所述第二区域的坐标之差，移动所述第一优化指纹图像与所述第二优化指纹图像以形成第一重构图像；
    其中，所述第一重构图像用于形成目标重构图像，所述目标重构图像为所述M张优化指纹图像重构形成的图像，所述目标重构图像用于进行指纹识别。
  8. 根据权利要求6所述的指纹识别装置，其特征在于，所述处理单元用于移动所述M张优化指纹图像以组合形成为一张重构图像，并根据所述重构图像的质量参数，调整所述M张指纹图像的移动距离，以形成目标重构图像，所述目标重构图像用于进行指纹识别。
  9. 根据权利要求1至8中任一项所述的指纹识别装置，其特征在于，所述N个指纹识别单元中的N个圆形微透镜中，相邻两个圆形微透镜的圆心距离小于75μm。
  10. 根据权利要求1至9中任一项所述的指纹识别装置，其特征在于，所述M个导光通道的方向中一个导光通道的方向相对于所述显示屏垂直，其它M-1个导光通道的方向相对于所述显示屏倾斜；或者，
    所述M个导光通道的方向均相对于所述显示屏倾斜。
  11. 根据权利要求1至10中任一项所述的指纹识别装置，其特征在于，所述M个导光通道分别与所述显示屏的夹角在30°至90°之间。
  12. 根据权利要求11所述的指纹识别装置，其特征在于，所述M个导光通道与所述显示屏的夹角相同。
  13. 根据权利要求1至12中任一项所述的指纹识别装置，其特征在于，所述M个导光通道中的两个导光通道在所述多个像素单元所在平面上的投影的夹角为90度。
  14. 根据权利要求1至13中任一项所述的指纹识别装置，其特征在于，所述M个像素单元中分别包括M个感光区域，所述M个感光区域分别位于所述M个导光通道的底部。
  15. 根据权利要求14所述的指纹识别装置，其特征在于，所述M个感光区域中的至少一个感光区域偏离于其所在的像素单元的中心设置。
  16. 根据权利要求15所述的指纹识别装置，其特征在于，所述至少一个感光区域向远离于所述圆形微透镜中心的方向偏离。
  17. 根据权利要求1至16中任一项所述的指纹识别装置，其特征在于，所述M个像素单元包括第一像素单元，所述第一像素单元中包括第一感光区域，所述第一像素单元与所述第一感光区域均为四边形；
    其中，所述第一像素单元的长和宽分别为L和W，所述第一感光区域的长和宽均大于等于0.1×W，W≤L，W和L均为正数。
  18. 根据权利要求17所述的指纹识别装置，其特征在于，所述第一感光区域的面积大于等于所述第一像素单元面积的95％。
  19. 根据权利要求1至18中任一项所述的指纹识别装置，其特征在于，所述圆形微透镜与所述M个像素单元所在平面之间的光路高度根据公式计算，所述公式为：h＝x×cotθ；
    其中，h为所述光路高度，x为所述M个感光区域中的第一感光区域的中心与所述圆形微透镜的中心在所述M个像素单元所在平面上的投影点之间的距离，θ为所述第一感光区域接收的第一目标指纹光信号与垂直方向的夹角，所述M个目标指纹光信号中所述第一目标指纹光信号与垂直方向的夹角大于所述M个目标指纹光信号中其它目标指纹光信号与垂直方向的夹角，所述垂直方向为垂直于所述显示屏的方向。
  20. 根据权利要求1至19中任一项所述的指纹识别装置，其特征在于，所述至少两层挡光层中的底层挡光层设置有与所述M个像素单元分别对应的M个通光小孔。
  21. 根据权利要求1至20中任一项所述的指纹识别装置，其特征在于，所述至少两层挡光层中的底层挡光层为所述M个像素单元表面的金属布线 层。
  22. 根据权利要求1至21中任一项所述的指纹识别装置，其特征在于，所述M个导光通道中的通光小孔由上至下孔径依次减小。
  23. 根据权利要求22所述的指纹识别装置，其特征在于，所述M个导光通道在所述至少两层挡光层的顶层挡光层中的通光小孔重合。
  24. 根据权利要求1至23中任一项所述的指纹识别装置，其特征在于，所述指纹识别单元还包括：
    透明介质层；
    其中，所述透镜介质层用于连接所述圆形微透镜、所述至少两层挡光层以及所述M个像素单元。
  25. 根据权利要求1至24中任一项所述的指纹识别装置，其特征在于，所述指纹识别单元还包括：
    光学滤波层；
    其中，所述光学滤波层设置在所述显示屏到所述M个像素单元所在平面之间的光路中，用于滤除非目标波段的光信号，以透过目标波段的光信号。
  26. 根据权利要求25所述的指纹识别装置，其特征在于，所述光学滤波层集成于所述M个像素单元表面。
  27. 根据权利要求25或26所述的指纹识别装置，其特征在于，所述光学滤波层设置在所述至少两层挡光层的底层挡光层与所述M个像素单元所在平面之间。
  28. 根据权利要求1至27中任一项所述的指纹识别装置，其特征在于，所述指纹识别装置和所述显示屏之间的距离为0至1mm。
  29. 一种电子设备，其特征在于，包括：显示屏；以及
    根据权利要求1至28中任一项所述的指纹识别装置，所述指纹识别装置设置于所述显示屏下方，以实现屏下光学指纹识别。
  30. 根据权利要求29所述的电子设备，其特征在于，所述指纹识别装置和所述显示屏之间的距离为0至1mm。
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US20210351216A1 (en) * 2020-05-08 2021-11-11 Visera Technologies Company Limited Optical imaging device
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US11776298B2 (en) * 2020-10-29 2023-10-03 Hangzhou Single Micro Electronic Co., Ltd. Under display fingerprint sensor with improved contrast ratio
JP2022170447A (ja) * 2021-04-28 2022-11-10 株式会社ジャパンディスプレイ 検出装置
CN113780103A (zh) * 2021-08-23 2021-12-10 北京极豪科技有限公司 生物信息识别模组及电子设备
CN113449685A (zh) * 2021-07-16 2021-09-28 维沃移动通信有限公司 光学指纹识别装置、光学指纹识别方法以及电子设备
KR20230077196A (ko) * 2021-11-25 2023-06-01 삼성전자주식회사 생체인증 장치를 포함하는 전자 장치
CN114815256B (zh) * 2022-04-15 2023-10-03 青岛虚拟现实研究院有限公司 虚拟现实头戴设备的屏幕参数调整方法、设备、存储介质
US20230401889A1 (en) * 2022-06-13 2023-12-14 Omnivision Technologies, Inc. Thin, multi-lens, optical fingerprint sensor adapted to image through cell phone displays and with multiple photodiode groups each having separate fields of view for each microlens
WO2024040492A1 (zh) * 2022-08-25 2024-02-29 京东方科技集团股份有限公司 一种光学传感器件及显示装置

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN205665716U (zh) * 2016-05-25 2016-10-26 深圳印象认知技术有限公司 感光像元、图像采集器、指纹采集设备及显示设备
CN107480579A (zh) * 2016-06-08 2017-12-15 联咏科技股份有限公司 光学传感器元件及指纹传感器装置
CN108734073A (zh) * 2017-04-14 2018-11-02 华为技术有限公司 一种检测装置及终端设备
CN109145702A (zh) * 2017-06-15 2019-01-04 神盾股份有限公司 光学指纹感测器
CN109583381A (zh) * 2018-11-30 2019-04-05 京东方科技集团股份有限公司 一种纹路识别装置、自发光显示面板
KR20190048282A (ko) * 2017-10-31 2019-05-09 주식회사 비욘드아이즈 디스플레이에 지문인식 기능을 구현하는 광 선택 구조 및 지문인식 기능을 구비한 디스플레이
CN208848221U (zh) * 2019-04-10 2019-05-10 深圳市汇顶科技股份有限公司 光学指纹识别装置和电子设备
CN109791612A (zh) * 2018-12-26 2019-05-21 深圳市汇顶科技股份有限公司 指纹识别装置和电子设备

Family Cites Families (72)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004020622A (ja) * 2002-06-12 2004-01-22 Nec Viewtechnology Ltd レンズシフト機構および投影型映像表示装置
US7274808B2 (en) 2003-04-18 2007-09-25 Avago Technologies Ecbu Ip (Singapore)Pte Ltd Imaging system and apparatus for combining finger recognition and finger navigation
JP2010094499A (ja) 2008-09-16 2010-04-30 Hitachi Maxell Ltd 画像取得装置及び生体情報取得装置
KR101550433B1 (ko) 2009-01-30 2015-09-07 삼성전자주식회사 반도체 장치의 제조 방법
TWI562077B (en) 2012-01-04 2016-12-11 Gingy Technology Inc Method for fingerprint recognition using dual camera and device thereof
JP2013172292A (ja) * 2012-02-21 2013-09-02 Sony Corp 撮像装置及び撮像素子アレイ
JP2015060855A (ja) 2013-09-17 2015-03-30 ソニー株式会社 固体撮像装置およびその製造方法、並びに電子機器
CN103577821A (zh) * 2013-09-19 2014-02-12 无锡指网生物识别科技有限公司 指纹模组
JP2015128131A (ja) 2013-11-27 2015-07-09 ソニー株式会社 固体撮像素子および電子機器
WO2016064223A1 (ko) 2014-10-24 2016-04-28 주식회사 비욘드아이즈 단위 화소 및 이를 포함하는 지문인식센서
CN104392227B (zh) 2014-12-15 2018-02-09 金虎林 活体指纹判断方法及系统
CN105893917A (zh) 2015-01-26 2016-08-24 联想(北京)有限公司 一种指纹识别器、指纹识别方法、装置及电子设备
CN104794433A (zh) 2015-03-27 2015-07-22 深圳市汇顶科技股份有限公司 指纹识别系统和方法
CN110275606B (zh) 2015-04-30 2022-11-29 原相科技股份有限公司 感测元件
CN107004130B (zh) * 2015-06-18 2020-08-28 深圳市汇顶科技股份有限公司 用于屏幕上指纹感应的屏幕下光学传感器模块
WO2017129126A1 (en) * 2016-01-31 2017-08-03 Shenzhen GOODIX Technology Co., Ltd. Under-screen optical sensor module for on-screen fingerprint sensing
CN105550664A (zh) * 2016-01-08 2016-05-04 上海箩箕技术有限公司 光学指纹传感器模组
CN105956545B (zh) 2016-04-29 2020-09-25 格科微电子（上海）有限公司 光学指纹识别装置的形成方法
WO2017204776A1 (en) 2016-05-23 2017-11-30 Quostagni Research Llc Electronic device including processing circuitry for sensing images from spaced apart sub-arrays and related methods
CN107437047A (zh) 2016-05-25 2017-12-05 深圳印象认知技术有限公司 感光像元、图像采集器、指纹采集设备及显示设备
CN106127000B (zh) 2016-06-17 2017-09-29 广东欧珀移动通信有限公司 一种指纹解锁方法及终端
US20180012069A1 (en) * 2016-07-06 2018-01-11 Samsung Electronics Co., Ltd. Fingerprint sensor, fingerprint sensor package, and fingerprint sensing system using light sources of display panel
KR20180005588A (ko) * 2016-07-06 2018-01-16 삼성전자주식회사 디스플레이 패널의 광원들을 이용한 지문 센서, 지문 센서 패키지 및 지문 센싱 시스템
JP2018019020A (ja) 2016-07-29 2018-02-01 ソニーセミコンダクタソリューションズ株式会社 撮像装置
CN106228144B (zh) * 2016-08-02 2023-10-13 京东方科技集团股份有限公司 一种指纹识别显示装置
CN206058224U (zh) 2016-08-04 2017-03-29 京东方科技集团股份有限公司 一种纹路采集器及显示装置
US10332929B2 (en) 2016-09-07 2019-06-25 Mei-Yen Lee Integrated sensing module and integrated sensing assembly using the same
CN106298859B (zh) 2016-09-30 2018-09-04 京东方科技集团股份有限公司 触控面板及显示装置
CN106773273B (zh) 2017-03-09 2020-02-18 京东方科技集团股份有限公司 显示装置和显示装置的驱动方法
CN110431668B (zh) 2017-03-30 2024-03-22 索尼半导体解决方案公司 固态摄像装置和电子设备
CN110096928B (zh) 2018-01-30 2021-08-06 京东方科技集团股份有限公司 指纹识别装置及显示装置
KR102350605B1 (ko) 2017-04-17 2022-01-14 삼성전자주식회사 이미지 센서
CN107436685B (zh) 2017-07-31 2020-07-07 京东方科技集团股份有限公司 显示装置、自发光的显示面板及手势识别方法
CN107728240A (zh) 2017-08-28 2018-02-23 苏州端景光电仪器有限公司 一种用于指纹识别的自聚焦透镜阵列及移动终端
US10474867B2 (en) 2017-09-28 2019-11-12 Apple Inc. Electronic device including mask collimation and related methods
WO2019093640A1 (en) 2017-11-10 2019-05-16 Lg Electronics Inc. Display device
CN207650835U (zh) 2017-11-30 2018-07-24 华为技术有限公司 显示面板和移动终端
WO2019112282A1 (ko) * 2017-12-04 2019-06-13 주식회사 비욘드아이즈 지문인식 기능을 구비한 디스플레이
KR102491855B1 (ko) 2017-12-11 2023-01-26 삼성전자주식회사 3d 지문센서 소자 및 이를 포함하는 전자 장치
CN107910344B (zh) 2017-12-18 2021-02-23 苏州晶方半导体科技股份有限公司 一种光学指纹识别芯片的封装结构以及封装方法
SE1751613A1 (en) 2017-12-21 2019-06-22 Fingerprint Cards Ab Biometric imaging device and method for manufacturing the biometric imaging device
KR20190085258A (ko) * 2018-01-10 2019-07-18 삼성전자주식회사 이미지 센서
KR20190088822A (ko) 2018-01-19 2019-07-29 삼성전자주식회사 지문 인식을 위한 센서 및 전자 장치
CN108885696B (zh) * 2018-02-06 2021-03-19 深圳市汇顶科技股份有限公司 屏下生物特征识别装置和电子设备
US10216975B1 (en) * 2018-02-23 2019-02-26 Shenzhen GOODIX Technology Co., Ltd. Optical imaging via imaging lens and imaging pinhole in under-screen optical sensor module for on-screen fingerprint sensing in devices having organic light emitting diode (OLED) screens or other screens
CN109154961A (zh) * 2018-02-26 2019-01-04 深圳市汇顶科技股份有限公司 基于利用透镜-针孔模块和其他光学设计的光学成像的lcd屏上光学指纹感测
CN108615746A (zh) 2018-04-28 2018-10-02 武汉天马微电子有限公司 显示面板和显示装置
CN208739213U (zh) * 2018-06-21 2019-04-12 宁波舜宇光电信息有限公司 感光组件、摄像模组及智能终端设备
JP2020013842A (ja) * 2018-07-17 2020-01-23 ソニーセミコンダクタソリューションズ株式会社 光電変換素子及び受光装置
CN109270988A (zh) 2018-08-31 2019-01-25 Oppo广东移动通信有限公司 显示屏组件及电子设备
CN209168144U (zh) 2018-09-25 2019-07-26 深圳市汇顶科技股份有限公司 指纹识别装置和终端设备
WO2020073169A1 (zh) 2018-10-08 2020-04-16 深圳市汇顶科技股份有限公司 生物特征识别的方法、装置和电子设备
CN208888842U (zh) * 2018-10-26 2019-05-21 深圳市汇顶科技股份有限公司 指纹识别装置和电子设备
CN109564623A (zh) * 2018-10-26 2019-04-02 深圳市汇顶科技股份有限公司 复合透镜结构、指纹识别装置和电子设备
CN109564627B (zh) 2018-10-30 2023-09-05 深圳市汇顶科技股份有限公司 具光学指纹防伪感测功能的屏下光学指纹装置及手持装置
CN109472236A (zh) 2018-11-02 2019-03-15 成都晶砂科技有限公司 一种全屏指纹识别屏及指纹识别方法
CN111435213B (zh) * 2019-01-11 2021-12-31 财团法人工业技术研究院 成像模块与使用其的生物识别装置
WO2020147018A1 (zh) * 2019-01-15 2020-07-23 深圳市汇顶科技股份有限公司 光学图像采集系统和电子设备
EP3706036B1 (en) * 2019-01-22 2021-12-22 Shenzhen Goodix Technology Co., Ltd. Fingerprint recognition apparatus and electronic device
CN209496381U (zh) * 2019-01-22 2019-10-15 深圳市汇顶科技股份有限公司 光学指纹识别模组和终端设备
CN111860452B (zh) 2019-02-02 2022-03-04 深圳市汇顶科技股份有限公司 指纹识别装置和电子设备
CN109858465A (zh) 2019-02-27 2019-06-07 昆山国显光电有限公司 用于指纹识别的显示装置
WO2020172876A1 (zh) * 2019-02-28 2020-09-03 深圳市汇顶科技股份有限公司 光学图像采集单元、光学图像采集系统和电子设备
CN110036397A (zh) 2019-03-05 2019-07-19 深圳市汇顶科技股份有限公司 指纹识别的方法、装置和终端设备
WO2020181493A1 (zh) * 2019-03-12 2020-09-17 深圳市汇顶科技股份有限公司 屏下指纹识别装置和电子设备
WO2020181489A1 (zh) * 2019-03-12 2020-09-17 深圳市汇顶科技股份有限公司 指纹识别装置、指纹识别方法和电子设备
KR20200124800A (ko) * 2019-04-24 2020-11-04 삼성디스플레이 주식회사 표시 장치
CN111095279B (zh) 2019-07-12 2023-09-08 深圳市汇顶科技股份有限公司 指纹检测装置和电子设备
CN211375617U (zh) 2019-08-23 2020-08-28 深圳市汇顶科技股份有限公司 指纹识别装置和电子设备
TW202113666A (zh) * 2019-09-22 2021-04-01 神盾股份有限公司 指紋感測模組及電子裝置
CN210864750U (zh) * 2019-10-18 2020-06-26 深圳市汇顶科技股份有限公司 指纹检测装置和电子设备
WO2021081891A1 (zh) 2019-10-31 2021-05-06 深圳市汇顶科技股份有限公司 用于指纹识别的方法、指纹识别装置和电子设备

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN205665716U (zh) * 2016-05-25 2016-10-26 深圳印象认知技术有限公司 感光像元、图像采集器、指纹采集设备及显示设备
CN107480579A (zh) * 2016-06-08 2017-12-15 联咏科技股份有限公司 光学传感器元件及指纹传感器装置
CN108734073A (zh) * 2017-04-14 2018-11-02 华为技术有限公司 一种检测装置及终端设备
CN109145702A (zh) * 2017-06-15 2019-01-04 神盾股份有限公司 光学指纹感测器
KR20190048282A (ko) * 2017-10-31 2019-05-09 주식회사 비욘드아이즈 디스플레이에 지문인식 기능을 구현하는 광 선택 구조 및 지문인식 기능을 구비한 디스플레이
CN109583381A (zh) * 2018-11-30 2019-04-05 京东方科技集团股份有限公司 一种纹路识别装置、自发光显示面板
CN109791612A (zh) * 2018-12-26 2019-05-21 深圳市汇顶科技股份有限公司 指纹识别装置和电子设备
CN208848221U (zh) * 2019-04-10 2019-05-10 深圳市汇顶科技股份有限公司 光学指纹识别装置和电子设备

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