CN111788575A

CN111788575A - Fingerprint identification device and electronic equipment

Info

Publication number: CN111788575A
Application number: CN202080001543.9A
Authority: CN
Inventors: 蒋鹏
Original assignee: Shenzhen Goodix Technology Co Ltd
Current assignee: Shenzhen Goodix Technology Co Ltd
Priority date: 2020-02-25
Filing date: 2020-02-25
Publication date: 2020-10-16
Anticipated expiration: 2040-02-25
Also published as: WO2021168666A1; CN111788575B

Abstract

The embodiment of the application provides a fingerprint identification device and electronic equipment, and the performance of the fingerprint identification device can be improved. This fingerprint identification device sets up in the below of display screen, includes: a microlens array; a plurality of light-blocking layers; the pixel array, the spatial sampling period P of the pixel used for receiving the fingerprint light signal of the same direction in the pixel array is less than half of the spatial imaging period of the display screen; the fingerprint light signals in the multiple directions are used for forming multiple fingerprint images, each of the multiple fingerprint images is subjected to low-pass filtering processing to form a first target fingerprint image, an average value of N rows and N columns of pixel values in the first target fingerprint image is used as one pixel value in a second target fingerprint image, and the second target fingerprint image is used for fingerprint identification. The technical scheme can eliminate moire fringes and further improve the performance of the fingerprint identification device, so that the fingerprint identification is quick in response, and the user experience is improved.

Description

Fingerprint identification device and electronic equipment

Technical Field

The embodiment of the application relates to the technical field of fingerprint identification, and more particularly relates to a fingerprint identification device and an electronic device.

Background

Optical fingerprint identification technique under screen is used extensively, in order to guarantee the fingerprint identification effect, generally need avoid producing moire fringe at fingerprint imaging in-process.

So far, in order to avoid appearing the moire fringe in the fingerprint image, increase the density of the pixel array of fingerprint identification module usually for the density of the pixel array of fingerprint identification module satisfies the nyquist sampling law relative to the density of the pixel array of display screen, promptly, makes the moire fringe be outside the fingerprint cycle, and is corresponding, promotes fingerprint identification's performance.

However, when the pixel array of the fingerprint identification module carries out fingerprint imaging based on the optical signals of a plurality of directions, moire fringes may still appear in the fingerprint image even if the density of the pixel array of the fingerprint identification module satisfies the nyquist sampling law relative to the density of the pixel array of the display screen.

In addition, for some fingerprint identification devices, such as ultra-thin large-area fingerprint identification devices, the data volume of fingerprint images processed by the fingerprint identification device can be greatly increased when the fingerprint identification device is applied to a high-pixel-density screen, so that when a user uses electronic equipment containing the fingerprint identification device, the quick response of fingerprint identification cannot be achieved, and the user experience is reduced.

Consequently, the pixel array to the fingerprint identification module carries out the scene of fingerprint formation of image based on the light signal of a plurality of directions, and the scheme that can avoid appearing moire fringe and fingerprint identification quick response in the fingerprint image is urgently needed, and is corresponding to promote the fingerprint identification effect, promote user experience.

Disclosure of Invention

The embodiment of the application provides a fingerprint identification device and electronic equipment, can solve the moire fringe problem that the fingerprint identification module appears to further reduce the data volume of fingerprint image, thereby promote fingerprint identification device's performance, promote user experience.

In a first aspect, a fingerprint identification device is provided, which is disposed below a display screen of an electronic device, and includes: a microlens array for being disposed below the display screen; the light blocking layers are arranged below the micro lens array, and each light blocking layer in the light blocking layers is provided with at least one light passing small hole corresponding to each micro lens in the micro lens array; the pixel array is arranged below the light blocking layers, the spatial sampling period P of pixels used for receiving fingerprint optical signals in the same direction in the pixel array is less than half of the spatial imaging period of the display screen, and each microlens in the microlens array converges the fingerprint optical signals in multiple directions returned after being reflected or scattered by a finger above the display screen to multiple pixels in the pixel array through a light-passing pore corresponding to each microlens; the fingerprint optical signals in the multiple directions are used for forming multiple fingerprint images, each fingerprint image in the multiple fingerprint images is subjected to low-pass filtering processing to form a first target fingerprint image, an average value of N rows and N columns of pixel values in the first target fingerprint image is used as one pixel value in a second target fingerprint image, N is a positive integer, and the second target fingerprint is used for fingerprint identification.

In the technical scheme, a plurality of pixels in the pixel array can receive fingerprint optical signals in a plurality of directions, the spatial sampling period of the pixels used for receiving the fingerprint optical signals in the same direction in the pixel array is smaller than half of the spatial imaging period of the display screen, so that the spatial sampling period of the pixels used for receiving the optical signals in the same direction can meet the Nyquist sampling law relative to the spatial imaging period of the display screen, namely, moire fringes can be avoided from appearing in each fingerprint image in the plurality of fingerprint images, and accordingly, the fingerprint identification effect is improved.

In addition, the fingerprint image used for fingerprint identification is constructed into the first target fingerprint image formed after low-pass filtering processing, and even if moire fringes are not completely eliminated through the Nyquist sampling law, the high-frequency characteristics of the moire fringes can be also based on the moire fringes when the moire fringes appear in the fingerprint image, the moire fringes in the fingerprint period are filtered through the low-pass filtering processing so as to ensure that the moire fringes do not appear in the fingerprint image, and accordingly, the fingerprint identification effect can be ensured.

Furthermore, the average value of the N rows and N columns of pixel values in the first target fingerprint image is used as one pixel value in the second target fingerprint image, and on the basis of eliminating moire fringes, the data volume of the fingerprint image is further reduced, so that the fingerprint identification can be quickly responded, and the user experience is improved.

In addition, the fingerprint identification device is not only suitable for the scene based on unilateral light signal carries out fingerprint identification, also is suitable for the scene based on multi-direction light signal carries out fingerprint identification, is equivalent to, on the basis of promoting the fingerprint identification effect, has increased fingerprint identification device's commonality.

In one possible implementation, the spatial sampling period N × P of the pixels in the second target fingerprint image is less than half of the spatial imaging period of the display screen.

In the technical scheme, when the spatial sampling period N P of the pixels in the images formed by the fingerprint optical signals in the same direction is less than half of the spatial imaging period of the display screen, the moire fringes under the screen of the fingerprint identification device can be eliminated or the period of the moire fringes is far away from the fingerprint period, so that the fingerprint identification performance is improved.

In a possible implementation manner, the spatial sampling period N × P in the second target fingerprint image is greater than or equal to half of the spatial imaging period of the display screen, and the fingerprint identification device is configured to have a preset deflection angle with respect to the display screen.

Through setting up predetermined deflection angle for the fingerprint cycle is kept away from to moire fringe's cycle under fingerprint identification device's the screen, eliminates moire fringe to fingerprint identification's influence, is favorable to promoting fingerprint identification's performance.

In one possible implementation, the fingerprint identification device has a first direction, and the first direction is parallel to the arrangement direction of the pixel array; the display screen is provided with a second direction, the second direction is parallel to the arrangement direction of pixels in the display screen, and an included angle between the first direction and the second direction is the preset deflection angle.

In one possible implementation, the range of the preset deflection angle is a tolerance range of the installation tolerance of the fingerprint identification device.

In one possible implementation, the preset deflection angle ranges from-45 degrees to 45 degrees and is not equal to 0.

In one possible implementation, the preset deflection angle is inversely proportional to the spatial imaging period of the display screen.

This technical scheme is favorable to fingerprint identification device's the cycle of moire fringe to keep away from the fingerprint cycle.

In one possible implementation, the spatial sampling period N × P of the second target fingerprint image is less than 75 microns.

In one possible implementation, the spatial sampling period N × P of the second target fingerprint image is 60 microns.

In a possible implementation manner, the pixel array includes a plurality of photosensitive regions respectively located at the bottom of the light-passing aperture, and at least one of the plurality of photosensitive regions is disposed offset from the center of the microlens on which it is located.

In a possible implementation manner, a top light-blocking layer of the plurality of light-blocking layers is provided with one light-passing small hole, and a bottom light-blocking layer of the plurality of light-blocking layers is provided with a plurality of light-passing small holes respectively corresponding to the plurality of pixels.

In a possible implementation manner, the fingerprint identification apparatus further includes: at least one color filter is located the top of this pixel array, and the fingerprint image that forms after the fingerprint light signal of these a plurality of directions passes through this color filter is used for carrying on fingerprint anti-fake.

Among this technical scheme, make the fingerprint light signal that different colours can be received to the pixel array through setting up the colour filter, can carry out the fingerprint anti-fake.

In one possible implementation, the color filters in each of the plurality of directions comprise color filters of different colors.

In one possible implementation, the color filters in each of the plurality of directions comprise color filters of the same color.

In one possible implementation, the color of the color filter is any one of the following colors: red, green, blue, yellow, white.

In a possible implementation manner, the fingerprint identification apparatus further includes: and the infrared cut-off filter is positioned above the pixel array and used for filtering infrared light signals so as to transmit visible light signals.

In a possible implementation manner, the fingerprint identification apparatus further includes: and the transparent medium layer is used for connecting the micro-lens array, the light blocking layers and the pixel array.

In one possible implementation manner, the transparent dielectric layer is a colored transparent dielectric layer.

In a second aspect, a fingerprint identification device is provided, which is disposed below a display screen of an electronic device, and includes: the micro lens array is arranged below the display screen; the light blocking layers are arranged below the micro lens array, and each light blocking layer in the light blocking layers is provided with at least one light passing small hole corresponding to each micro lens in the micro lens array; the pixel array is arranged below the light blocking layers, the spatial sampling period P of pixels used for receiving fingerprint optical signals in the same direction in the pixel array is less than half of the spatial imaging period of the display screen, and each microlens in the microlens array converges the fingerprint optical signals in multiple directions returned after being reflected or scattered by a finger above the display screen to multiple pixels in the pixel array through a light-passing pore corresponding to each microlens;

the fingerprint optical signals in multiple directions are used for forming multiple fingerprint images, the average value of N rows and N columns of pixel values in each fingerprint image in the multiple fingerprint images is used as one pixel value in a third target fingerprint image, the third target fingerprint image is subjected to low-pass filtering processing to form a fourth target fingerprint image, the average value of L rows and L columns of pixel values in the fourth target fingerprint image is used as one pixel value in a fifth target fingerprint image, and the fifth target fingerprint image is used for fingerprint identification, wherein L is a positive integer;

the spatial sampling period N x P of the pixels in the third target fingerprint image is less than half of the spatial imaging period of the display screen.

This technical scheme can be so that fingerprint identification device is on the basis of eliminating moire fringe, promptly, guarantees the fingerprint identification effect, further reduces the data volume of fingerprint image for fingerprint identification can quick response, and is corresponding, has promoted user's experience.

In a third aspect, an electronic device is provided, including: a display screen; and

the fingerprint identification device in the first aspect or any one of the possible implementations of the first aspect or the second aspect, where the fingerprint identification device is disposed below the display screen to implement an off-screen optical fingerprint identification.

In one possible implementation, the distance between the fingerprint recognition device and the display screen is 0 to 1 mm.

The fingerprint identification device is arranged in the electronic equipment, and the fingerprint identification performance of the electronic equipment is improved by improving the fingerprint identification performance of the fingerprint identification device.

Drawings

Fig. 1 is a schematic plan view of an electronic device to which the embodiments of the present application may be applied.

Fig. 2 and 3 are a schematic cross-sectional view and a schematic top view of a fingerprint recognition device according to an embodiment of the present application.

Fig. 4 is a functional block diagram of a fingerprint identification device according to an embodiment of the present application.

Fig. 5 is a schematic diagram of an optical path direction according to an embodiment of the present application.

FIG. 6 is a schematic block diagram of a fingerprint identification system of an embodiment of the present application.

Fig. 7 is a schematic diagram of a fingerprint identification device according to an embodiment of the present application, the fingerprint identification device having a preset deflection angle with respect to a display screen.

Fig. 8 is a schematic diagram of a fingerprint identification device according to an embodiment of the present application, the fingerprint identification device having a predetermined deflection angle with respect to a display screen.

Fig. 9 is a schematic diagram of a fingerprint identification device according to an embodiment of the present application, the fingerprint identification device having a predetermined deflection angle with respect to a display screen.

Fig. 10 is a schematic block diagram of an electronic device according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings.

It should be understood that the embodiments of the present application can be applied to optical fingerprint systems, including but not limited to optical fingerprint identification systems and products based on optical fingerprint imaging, and the embodiments of the present application are only described by way of example, but not limited to any limitation, and the embodiments of the present application are also applicable to other systems using optical imaging technology, etc.

As a common application scenario, the optical fingerprint system provided by the embodiment of the application can be applied to smart phones, tablet computers and other mobile terminals or other electronic devices with display screens; more specifically, in the above electronic device, the fingerprint recognition device may be embodied as an optical fingerprint device, which may be disposed in a partial area or an entire area below the display screen, thereby forming an Under-screen (Under-display) optical fingerprint system. Alternatively, the fingerprint identification device may be partially or completely integrated into a display screen of the electronic device, so as to form an In-display (In-display) optical fingerprint system.

Fig. 1 is a schematic structural diagram of an electronic device to which the embodiment of the present invention is applicable, where the electronic device 10 includes a display screen 120 and an optical fingerprint device 130, where the optical fingerprint device 130 is disposed in a local area below the display screen 120. The optical fingerprint device 130 comprises an optical fingerprint sensor including a sensing array 133 having a plurality of optical sensing units 131, where the sensing array 133 is located or a sensing area thereof is a fingerprint detection area 103 of the optical fingerprint device 130. As shown in fig. 1, the fingerprint detection area 103 is located in a display area of the display screen 120. In an alternative embodiment, the optical fingerprint device 130 may be disposed at other locations, such as the side of the display screen 120 or the edge opaque region of the electronic device 10, and the optical path is designed to guide the optical signal of at least a portion of the display area of the display screen 120 to the optical fingerprint device 130, such that the fingerprint detection area 103 is actually located in the display area of the display screen 120.

It should be appreciated that the area of the fingerprint sensing area 103 may be different from the area of the sensing array of the optical fingerprint device 130, for example, by optical path design such as lens imaging, reflective folded optical path design, or other optical path design such as light converging or reflecting, the area of the fingerprint sensing area 103 of the optical fingerprint device 130 may be larger than the area of the sensing array of the optical fingerprint device 130. In other alternative implementations, if light path guidance is performed using, for example, light collimation, fingerprint sensing area 103 of optical fingerprint device 130 may also be designed to substantially coincide with the area of the sensing array of optical fingerprint device 130.

Therefore, when the user needs to unlock or otherwise verify the fingerprint of the electronic device, the user only needs to press the finger on the fingerprint detection area 103 of the display screen 120, so as to input the fingerprint. Since fingerprint detection can be implemented in the screen, the electronic device 10 with the above structure does not need to reserve a space on the front surface thereof to set a fingerprint key (such as a Home key), so that a full-screen scheme can be adopted, that is, the display area of the display screen 120 can be substantially extended to the front surface of the whole electronic device 10.

In some embodiments of the present application, as shown in fig. 1, the optical fingerprint apparatus 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 and other auxiliary circuits electrically connected to the sensing array, which can be fabricated on a chip (Die) by a semiconductor process, such as an optical imaging chip or an optical fingerprint sensor, the sensing array is specifically a Photo detector (Photo detector) array, which includes a plurality of Photo detectors distributed in an array, and the Photo detectors can be used as the above-mentioned optical sensing units; the optical assembly 132 may be disposed above the sensing array of the light detection portion 134, and may specifically include a light guiding layer or a light path guiding structure for guiding the reflected light reflected from the surface of the finger to the sensing array for optical detection, and other optical elements.

It should be understood that the optical assembly 132 may be packaged with the same optical fingerprint component as the light detection portion 134. For example, the optical component 132 may be packaged in the same optical fingerprint chip as the optical detection portion 134, or the optical component 132 may be disposed outside the chip where the optical detection portion 134 is located, such as attaching the optical component 132 on the chip, or integrating some components of the optical component 132 into the chip.

Alternatively, the light guide layer or the light path guiding structure may also specifically employ a Micro-Lens (Micro-Lens) layer, which has a Micro-Lens array formed by a plurality of Micro-lenses, which may be formed above the sensing array of the light detecting portion 134 through a semiconductor growth process or other processes, and each Micro-Lens may respectively correspond to one of the sensing units of the sensing array. And, other optical film layers may be further formed between the microlens layer and the sensing unit, such as a dielectric layer or a passivation layer, and more specifically, a light blocking layer having micro holes may be further included between the microlens layer and the sensing unit, where the micro holes are formed between the corresponding microlenses and the sensing unit, and the light blocking layer may block optical interference between adjacent microlenses and the sensing unit, and enable light rays corresponding to the sensing unit to be converged into the micro holes through the microlenses and transmitted to the sensing unit through the micro holes to perform optical fingerprint imaging.

As an alternative embodiment, the display screen 120 may adopt a display screen having a self-Light Emitting display unit, such as an Organic Light-Emitting Diode (OLED) display screen or a Micro-LED (Micro-LED) display screen. Taking the OLED display screen as an example, the optical fingerprint device 130 may use the display unit (i.e., the OLED light source) of the OLED display screen 120 located in the fingerprint detection area 103 as an excitation light source for optical fingerprint detection. When the finger 140 is pressed against the fingerprint detection area 103, the display screen 120 emits a beam of light 111 toward the target finger 140 above the fingerprint detection area 103, and the light 111 is reflected at the surface of the finger 140 to form reflected light or scattered light by scattering through the inside of the finger 140 to form scattered light, which is collectively referred to as reflected light for convenience of description in the related patent application. Because the ridges (ridges) and valleys (valley) of the fingerprint have different light reflection capacities, the reflected light 151 from the ridges and 152 from the valleys have different light intensities, and after passing through the optical assembly 132, the reflected light is received by the sensing array 134 in the optical fingerprint device 130 and converted into corresponding electrical signals, i.e., fingerprint detection signals; based on the fingerprint detection signal, fingerprint image data can be obtained, and fingerprint matching verification can be further performed, so that an optical fingerprint identification function is realized in the electronic device 10.

It should be understood that the electronic device 10 may also include a transparent protective cover plate, which may be a glass cover plate or a sapphire cover plate, positioned over the display screen 120 and covering the front face of the electronic device 10. Because, in the embodiment of the present application, the pressing of the finger on the display screen 120 actually means pressing on the cover plate above the display screen 120 or the surface of the protective layer covering the cover plate.

It should also be understood that electronic device 10 may also include a circuit board 150 disposed below optical fingerprint arrangement 130. The optical fingerprint device 130 may be adhered to the circuit board 150 by a back adhesive, and electrically connected to the circuit board 150 by soldering a pad and a wire. Optical fingerprint device 130 may be electrically interconnected and signal-transferred to other peripheral circuits or other components of electronic device 10 via circuit board 150. For example, the optical fingerprint device 130 may receive a control signal of a processing unit of the electronic apparatus 10 through the circuit board 150, and may also output a fingerprint detection signal from the optical fingerprint device 130 to the processing unit or the control unit of the electronic apparatus 10 through the circuit board 150, or the like.

On the other hand, in some embodiments, the optical fingerprint device 130 may include only one optical fingerprint sensor, where the area of the fingerprint detection area 103 of the optical fingerprint device 130 is small and the position is fixed, so that the user needs to press a finger to a specific position of the fingerprint detection area 103 when performing a fingerprint input, otherwise the optical fingerprint device 130 may not acquire a fingerprint image and the user experience is poor. In other alternative embodiments, optical fingerprint device 130 may specifically include a plurality of optical fingerprint sensors; the plurality of optical fingerprint sensors may be disposed side by side below the display screen 120 in a splicing manner, and sensing areas of the plurality of optical fingerprint sensors jointly form the fingerprint detection area 103 of the optical fingerprint device 130. That is, the fingerprint detection area 103 of the optical fingerprint device 130 may include a plurality of sub-areas, each of which corresponds to a sensing area of one of the optical fingerprint sensors, so that the fingerprint collection area 103 of the optical fingerprint device 130 may be extended to a main area of a lower half portion of the display screen, i.e., to a region where a finger is normally pressed, thereby implementing a blind-touch fingerprint input operation. Alternatively, when the number of optical fingerprint sensors is sufficient, the fingerprint detection area 103 may also be extended to half the display area or even the entire display area, thereby enabling half-screen or full-screen fingerprint detection.

It should also be understood that in the embodiments of the present application, the sensing array in the optical fingerprint device may also be referred to as a pixel array, and the optical sensing unit or the sensing unit in the sensing array may also be referred to as a pixel unit or a pixel.

It should be noted that, optical fingerprint device in this application embodiment also can be called optical fingerprint identification module, fingerprint identification device, fingerprint identification module, fingerprint collection device etc. but above-mentioned term mutual replacement.

However, when the pixel array of fingerprint identification module carries out fingerprint imaging based on the optical signal of a plurality of directions, even make the density of the pixel array of fingerprint identification module satisfy the nyquist sampling law relative to the density of the pixel array of display screen, still can appear the moire fringe in the fingerprint image.

In order to eliminate the influence of moire fringe under the screen to fingerprint identification performance and promote performance and the commonality of fingerprint identification module, this application embodiment is through promoting the space sampling density that is used for receiving the pixel of the fingerprint light signal of the equidirectional in the pixel array, reduce the space sampling cycle that is used for receiving the pixel of the fingerprint light signal of the equidirectional in the pixel array promptly, make it be less than half of the space imaging cycle of display screen, and form first target fingerprint image after each fingerprint image in a plurality of fingerprint images of the fingerprint light signal formation of a plurality of directions passes through low pass filtering, the average value of N row pixel value in this first target fingerprint image is as a pixel value in the second target fingerprint image, this second target fingerprint image is used for carrying out fingerprint identification. Therefore, the fingerprint identification device can eliminate moire fringes under a screen or enable the period of the moire fringes to be far away from the fingerprint period, further, the data volume of a fingerprint image is reduced, the fingerprint identification is enabled to respond quickly, correspondingly, the performance of the fingerprint identification is improved, and the experience of a user is improved.

The fingerprint identification device and the electronic device of the present application will be described with reference to the embodiments.

As shown in fig. 2 and 3, the fingerprint recognition device 200 may include: microlens array 210, a plurality of light blocking layers, pixel array 250. Wherein, the spatial sampling period of the pixels for receiving fingerprint light signals of the same direction in the pixel array 250 is less than half of the spatial imaging period of the display screen. The fingerprint light signals in the multiple directions are used for forming multiple fingerprint images, and each fingerprint image in the multiple fingerprint images forms a first target fingerprint image after being subjected to low-pass filtering processing.

Optionally, in this embodiment of the present application, digital average processing may be performed on the first target fingerprint image, that is, an average value of N rows and N columns of pixel values in the first target fingerprint image after low-pass filtering processing may be used as one pixel value in the second target fingerprint image, where N is a positive integer. The following detailed description will be given with reference to specific embodiments, which will not be described in detail herein.

Optionally, in this embodiment of the present application, the fingerprint images formed by the fingerprint optical signals in the same direction may be subjected to digital averaging first, and then the fingerprint images subjected to the digital averaging are subjected to low-pass filtering, that is, an average value of N rows and N columns of pixel values in the fingerprint images formed by receiving the fingerprint optical signals in the same direction may be used as one pixel value in a third target fingerprint image, the third target fingerprint image is subjected to the low-pass filtering to form a fourth target fingerprint image, and the fourth target fingerprint image is used for fingerprint identification; wherein a spatial sampling period N P of pixels in the third target fingerprint image is less than half of a spatial imaging period of the display screen.

Optionally, in this embodiment of the application, when the pixel density of the pixel array for receiving the fingerprint optical signals in the same direction is relatively large, the first digital averaging processing may be performed on the fingerprint images formed by the fingerprint optical signals in the same direction, and then the low-pass filtering processing may be performed on the fingerprint images after the first digital averaging processing, at this time, the pixel density of the fingerprint images after the first digital averaging processing is still relatively large, and in order to reduce the data amount of the fingerprint images, the second digital averaging processing may be performed on the fingerprint images after the low-pass filtering processing. That is, an average value of N rows and N columns of pixel values in a fingerprint image formed by receiving fingerprint light signals in the same direction may be used as one pixel value in a third target fingerprint image, the third target fingerprint image is subjected to a low-pass filtering process to form a fourth target fingerprint image, an average value of L rows and L columns of pixel values in the fourth target fingerprint image is used as one pixel value in a fifth target fingerprint image, the fifth target fingerprint image is used for fingerprint identification, wherein L is a positive integer; wherein a spatial sampling period N P of pixels in the third target fingerprint image is less than half of a spatial imaging period of the display screen.

Alternatively, the spatial imaging period of the display screen may be a period of a pixel unit of the display screen.

Optionally, the spatial imaging period of the display screen may also be a ratio of a pixel unit period of the display screen to a scaling factor K of the optical imaging system, where K is a scaling ratio between an image displayed in a photosensitive area in a pixel unit of the fingerprint identification device and an image captured by the pixel unit in the photosensitive area.

Alternatively, the display screen may be an OLED screen or an LCD screen.

The microlens array 210 is disposed under the display screen and is composed of a plurality of microlenses. Alternatively, the microlens may be a colored microlens, such as a spherical cap of the microlens with a color that may be green or cyan or other color.

In the embodiment of the present application, a top light-blocking layer of the plurality of light-blocking layers is provided with one light-passing aperture, and a bottom light-blocking layer of the plurality of light-blocking layers is provided with a plurality of light-passing apertures corresponding to the plurality of pixels, respectively.

The plurality of light-blocking layers are disposed below the microlens array 210, and may include a first light-blocking layer 220, a second light-blocking layer 230, and a third light-blocking layer 240, and at least one light-passing aperture corresponding to each microlens in the microlens array is disposed in each light-blocking layer of the plurality of light-blocking layers.

As one example, in the first light-blocking layer 220, a first small hole 221 corresponding to the first microlens 211 is provided, a second small hole 231 and a third small hole 232 corresponding to the first microlens 211 are provided in the second light-blocking layer 230, a fourth small hole 241 and a fifth small hole 242 corresponding to the first microlens 211 are provided in the third light-blocking layer 240, and the fourth small hole 241 and the fifth small hole 242 correspond to the

pixel units

261 and 262, respectively.

It should be understood that the figure shows that the fingerprint identification device 200 includes three light-blocking layers, and the light-blocking layers in this application may be two layers or more, which is not specifically limited in this application.

The pixel array 250 is configured to be disposed below the plurality of light blocking layers, a spatial sampling period P of a pixel in the pixel array, which is used for receiving fingerprint optical signals in the same direction, is less than half of a spatial imaging period of the display screen, at least one microlens in the microlens array 210 converges, through a light-passing aperture corresponding to the at least one microlens, fingerprint optical signals in a plurality of directions, which are returned after being reflected or scattered by a finger above the display screen, into a plurality of pixels in the pixel array, respectively, and the fingerprint optical signals in the plurality of directions are used for identifying fingerprint information of the finger.

As an example, each pixel unit in the pixel array 250 may further include a photosensitive region, for example, the pixel unit 251 includes a photosensitive region 261, and the pixel unit 252 includes a photosensitive region 262. The multiple photosensitive areas are used for receiving fingerprint optical signals in different directions.

Alternatively, the plurality of photosensitive regions may be enabled to receive fingerprint light signals in different directions by adjusting the area size of the photosensitive region in each pixel unit and/or the relative position relationship of the photosensitive region in the pixel unit.

Optionally, the fingerprint light signals of multiple directions can also be used for fingerprint anti-counterfeiting.

As an example, as shown in fig. 3, one microlens corresponds to four pixel units, and the center of the microlens is offset with respect to the center of the four pixel units by a certain amount. The photosensitive areas in the four pixel units receive fingerprint optical signals in different directions through at least one light-transmitting small hole in the light blocking layer so as to carry out fingerprint identification or fingerprint anti-counterfeiting. The spatial sampling period of the pixels for receiving the fingerprint light signals in the same direction is less than half of the spatial imaging period of the display screen.

In the embodiment of the present application, one light-passing aperture 221 is disposed in the top light-blocking layer of the plurality of light-blocking layers, and a plurality of light-passing apertures corresponding to a plurality of pixels are disposed in the bottom light-blocking layer of the plurality of light-blocking layers, that is, light-passing

apertures

241 and 242 corresponding to

pixel units

261 and 262 are disposed in the bottom light-blocking layer.

As another example, each microlens in the embodiment of the present application may also correspond to one pixel unit, in this case, a plurality of microlenses form a microlens set, and the plurality of microlenses in the microlens set are respectively used for receiving fingerprint light signals in different directions to perform fingerprint identification or fingerprint anti-counterfeiting. The spatial sampling period of the pixels for receiving the fingerprint light signals in the same direction is less than half of the spatial imaging period of the display screen.

In the technical scheme, a plurality of pixels in the pixel array can receive fingerprint optical signals in a plurality of directions, and the spatial sampling period of the pixels used for receiving the fingerprint optical signals in the same direction in the pixel array is set to be less than half of the spatial imaging period of the display screen, namely, moire fringes can be avoided from appearing in each fingerprint image in the plurality of fingerprint images, and accordingly, the fingerprint identification effect is improved. In addition, the fingerprint image used for fingerprint identification is constructed into the first target fingerprint image formed after low-pass filtering processing, even though moire fringes are not completely eliminated through the Nyquist sampling law, the high-frequency characteristic of the moire fringes can be also based on the occurrence of the moire fringes in the fingerprint image, the moire fringes in the fingerprint period are filtered through the low-pass filtering processing so as to ensure that the moire fringes do not occur in the fingerprint image, accordingly, the fingerprint identification effect can be ensured, further, the average value of N rows and N columns of pixel values in the first target fingerprint image is used as one pixel value in the second target fingerprint image, the data volume of the fingerprint image can be reduced, the fingerprint identification is enabled to be fast in response, and the user experience is improved.

As shown in fig. 4, four pixel units are corresponding to one microlens, and numbers "1", "2", "3" and "4" respectively indicate the pixel units for receiving fingerprint light signals in four different directions under each microlens, and the pixel units for receiving fingerprint light signals in the same direction are not adjacent to each other.

It should be understood that fig. 4 only shows the relative positions of the pixel units corresponding to the numbers "1", "2", "3" and "4", but this should not limit the present application in any way.

In the embodiment of the present application, the pixel units for receiving the fingerprint optical signals in the same direction form one fingerprint image, that is, four fingerprint images can be formed under the condition that one microlens corresponds to four pixel units, wherein each fingerprint image in the four fingerprint images can be used for fingerprint identification and/or fingerprint anti-counterfeiting, or the four fingerprint images can be combined into one image for fingerprint identification and/or fingerprint anti-counterfeiting.

When the spatial sampling period of the pixels for receiving the fingerprint light signals in the same direction in the pixel array is less than half of the spatial imaging period of the display screen, for example, the distance between the pixel units corresponding to two numbers "1" is less than half of the spatial imaging period of the display screen.

In the embodiment of the present application, the four fingerprint images may be subjected to low pass filtering firstly, so as to eliminate moire fringes at a high frequency and a pixel structure period of a screen at a high frequency, and then the four fingerprint images after the low pass filtering are subjected to pixel averaging respectively, that is, an average value of pixels of N rows and N columns of pixel units for receiving fingerprint optical signals in the same direction is used as a pixel value in a target fingerprint image, and as shown in fig. 4, an average value of pixels of 2 rows and 2 columns of pixel units for receiving fingerprint optical signals in the same direction, that is, an average value of pixels of 4 pixel units, is used as a pixel value in a fingerprint pattern formed by the fingerprint optical signals in the same direction. Specifically, the pixel average value of the pixel unit corresponding to four digital "1" is taken as one pixel value in the fingerprint image formed by the fingerprint light signal corresponding to the direction of "1"; the pixel average value of the pixel unit corresponding to the four numbers of '2' is used as one pixel value in the fingerprint image formed by the fingerprint light signals corresponding to the '2' direction; the pixel average value of the pixel unit corresponding to the four numbers of '3' is used as one pixel value in the fingerprint image formed by the fingerprint light signals corresponding to the direction of '3'; the pixel average value of the pixel unit corresponding to the four digital '4' is used as one pixel value in the fingerprint image formed by the fingerprint light signal corresponding to the '4' direction.

Alternatively, when the spatial sampling period of the pixels in the pixel array for receiving the fingerprint light signals in the same direction is not less than half of the spatial imaging period of the display screen, but moire fringes can be eliminated after the low-pass filtering process, the spatial sampling period of the pixels in the fingerprint image is also available.

According to the technical scheme, the data volume of the fingerprint image can be further reduced while the moire fringes are eliminated, the transmission time of the data signal of the fingerprint image between the fingerprint identification device and the central processing unit of the electronic equipment is reduced, the fingerprint identification device can respond quickly, the performance of the fingerprint identification device is improved, and the user experience is improved.

Optionally, in the embodiment of the present application, pixel averaging may be performed first, and then the fingerprint image after the pixel averaging is subjected to low-pass filtering to obtain the target fingerprint image. In this case, the spatial sampling period of the pixels of the fingerprint image formed after the pixel averaging process is less than half of the spatial imaging period of the display screen. Alternatively, when the spatial sampling period of the pixels of the fingerprint image formed after the pixel averaging process is not less than half of the spatial imaging period of the display screen, but moire fringes can be eliminated after the low-pass filtering process, the spatial sampling period of the pixels in the fingerprint image is also available.

Alternatively, the low-pass filtering and pixel averaging processes may be performed inside the fingerprint recognition device, i.e., inside the chip; the fingerprint identification device may also be implemented between the fingerprint identification device and a central processing unit of the terminal device, that is, implemented outside the chip, which is not specifically limited in this embodiment of the present application.

Optionally, the low-pass filtering process in this application may be implemented by a configurable low-pass filter, such as a gaussian filter, a butterworth filter, a chebyshev filter, or the like, and may also be implemented by using window sliding, which is not specifically limited in this embodiment of the present application.

The following describes the optical path direction of the embodiment of the present application with reference to fig. 5, and fig. 5 is a schematic diagram of an optical path direction of the embodiment of the present application. As shown in fig. 5, the light beams in two different directions include a first light beam 271 and a second light beam 272, the light in the first light beam 271 passes through the microlens array 210 and at least one light-passing aperture in the plurality of light-blocking layers and is respectively converged into light-

sensing areas

262 and 264 in a plurality of pixel units in the pixel array, and the light-

sensing areas

262 and 264 respectively correspond to different microlenses in the microlens array 210. The light in the second light beam 272 passes through the microlens array 210 and at least one light-passing aperture in the plurality of light-blocking layers and is converged into

photosensitive regions

261 and 263 in a plurality of pixel units in the pixel array, respectively, and the

photosensitive regions

261 and 263 correspond to different microlenses in the microlens array 210, respectively. By setting the spatial sampling period of the pixels in the pixel array for receiving the fingerprint light signals in the same direction, that is, the distance between the pixels where the

photosensitive regions

261 and 263 are located (or the distance between the pixels where the

photosensitive regions

262 and 264 are located), to be less than half of the spatial imaging period of the display screen, the fingerprint identification device can eliminate moire fringes or make the period of the moire fringes far away from the fingerprint period, so that the fingerprint identification performance is improved, and the universality of the fingerprint identification device is increased.

It should be understood that fig. 5 only shows the light path direction in the cross-sectional view of the fingerprint identification device, and the cross-sectional view includes light in two different directions, in practice, each microlens may correspond to more pixel units, each pixel unit may be respectively used for receiving light in one direction, and at this time, the microlens converges light in multiple directions into corresponding multiple pixel units through its corresponding light-passing aperture.

FIG. 6 is a schematic block diagram of a fingerprint identification system of an embodiment of the present application. As shown in fig. 6, in the fingerprint identification system, since the structural form of the pixel unit of the display screen is similar to that of the pixel unit in the fingerprint identification device, moire fringes may be generated when the fingerprint identification device images based on light transmitted through the display screen, and the performance of fingerprint identification may be affected.

As shown in fig. 6, if the structural period of the pixel unit of the display screen is M, the spatial imaging period of the display screen is M/K, and K is the scaling ratio between the image displayed in the pixel unit in the fingerprint identification device and the image collected by the pixel unit in the pixel unit. The spatial sampling period for receiving pixels in the same direction in the fingerprint identification device is P. The space sampling period of the pixel used for receiving the fingerprint light signals in the same direction in the pixel array is set to be smaller than half of the space imaging period of the display screen, namely P < M/2K, so that the fingerprint identification device can eliminate moire fringes or enable the period of the moire fringes to be far away from the fingerprint period, the fingerprint identification performance is improved, and the universality of the fingerprint identification device is improved.

It should be understood that, after taking the average value of the pixels of N rows and N columns of the fingerprint light signals receiving the same direction as a pixel value in the fingerprint image formed by the fingerprint light signals receiving the same direction, the period of the pixels in the fingerprint image becomes N × P.

In one possible implementation, N × P is less than half of the spatial imaging period of the display screen.

In the technical scheme, when the spatial sampling period N P of the image formed by the fingerprint optical signals in the same direction is less than half of the spatial imaging period of the display screen, the moire fringes under the screen of the fingerprint identification device can be eliminated or the period of the moire fringes is far away from the fingerprint period, so that the fingerprint identification performance is improved.

In another possible implementation manner, the spatial sampling period N × P in the fingerprint image formed by the fingerprint light signals in the same direction is greater than or equal to half of the spatial imaging period of the display screen, and the fingerprint identification device is configured to have a preset deflection angle with respect to the display screen.

In one embodiment of the present application, the average value of the pixels of N1 rows and N2 columns receiving the same direction of fingerprint light signals is taken as a pixel value in the fingerprint image, N1 is different from N2, in which case the fingerprint recognition device is configured to have a preset deflection angle with respect to the display screen.

The case of a preset deflection angle between the fingerprint identification device and the display screen according to the embodiment of the present application will be described with reference to fig. 7.

As shown in fig. 7, the electronic device 300 includes a protective cover 310, a display screen may be disposed below the protective cover 310, and a fingerprint recognition device 320 may be disposed below the display screen. The fingerprint acquisition area of the fingerprint identification device 320 is located within the display area 330 of the display screen. The fingerprint recognition device 320 has a preset deflection angle relative to the display screen.

Optionally, the pixel array 331 in the fingerprint identification device 320 has a first direction, and the first direction of the pixel array 331 in the fingerprint identification device 320 is a direction parallel to the row arrangement of the pixel array in the fingerprint identification device; the pixel unit array 340 in the display screen has a second direction, the second direction of the pixel unit array 340 in the display screen is parallel to the row arrangement direction of the pixel units in the display screen, and a first included angle θ is formed between the first direction of the pixel array 311 and the second direction of the pixel unit array 340 in the display screen, so that the fingerprint identification device has the preset deflection angle relative to the display screen. For example, the preset deflection angle may range from-45 degrees to 45 degrees, and is not equal to zero, based on the preset deflection angle θ; the preset deflection angle theta can also range from-15 degrees to 15 degrees and is not equal to zero; for another example, the preset deflection angle θ may also range from-2.5 degrees to 2.5 degrees and is not equal to zero.

Optionally, a preset deflection angle between the fingerprint identification device 320 of the embodiment of the present application and the display screen may also be as shown in fig. 8 and 9, where the preset deflection angle θ may range from-45 degrees to 45 degrees and is not equal to zero; the preset deflection angle theta can also range from-15 degrees to 15 degrees and is not equal to zero; for another example, the preset deflection angle θ may also range from-2.5 degrees to 2.5 degrees and is not equal to zero.

It should be understood that, when the fingerprint identification device of the embodiment of the present application is applied to display screens with different parameters, the preset deflection angle of the embodiment of the present application may also be different due to different parameters of the display screens, for example, the range of the preset deflection angle may be within a tolerance range of an installation tolerance of the fingerprint identification device; the preset deflection angle may also be inversely proportional to the spatial imaging period of the display screen, and so on.

Optionally, in this embodiment of the application, a plane where the pixel array in the fingerprint identification module is located may also have a preset deflection angle with a plane where the display screen is located.

Through setting up predetermined angle for the fingerprint cycle is kept away from to the cycle of moire fringe under fingerprint identification device's the screen, eliminates moire fringe to fingerprint identification's influence, is favorable to promoting fingerprint identification's performance.

It should be understood that the fingerprint recognition device 320 may also include a circuit board electrically connected to the fingerprint recognition device 320.

Optionally, in the embodiment of the present application, the circuit board may rotate together with the fingerprint recognition device 320, and has a preset deflection angle with the display screen; the rotation angle of the circuit board can be the same as or different from that of the fingerprint identification device 320; the circuit board may not rotate with the fingerprint recognition device 320.

It should be understood that fig. 7 to 9 are only examples of the embodiments of the present application and should not be construed as limiting the embodiments of the present application.

In one possible implementation, the spatial sampling period N × P of the fingerprint image formed by the fingerprint light signals in the same direction is less than 75 micrometers.

For example, the unit period P of the microlens, that is, the distance between pixels for receiving the same direction may be 15 micrometers, and the spatial sampling period N P of the fingerprint image formed by the fingerprint light signals in the same direction is 60 micrometers by taking the average value of the pixels of the 4 rows and 4 columns of the fingerprint light signals in the same direction as one pixel value in the fingerprint image. The data volume of the fingerprint image is compressed by 16 times by taking the pixel average value of the pixels of 4 rows and 4 columns as one pixel value in the fingerprint image, so that the transmission time of the data signal of the fingerprint image between the fingerprint identification device and the terminal equipment processor is greatly reduced, and the quick response of fingerprint identification can be realized. As another example, the distance between the pixels for receiving the same direction may also be 14.4 micrometers or 14.6 micrometers, and the average value of the pixels of the 4 rows and 4 columns of the fingerprint light signals of the same direction is taken as a pixel value in the fingerprint image.

It should be understood that, in the above scheme, an average pixel value of pixels receiving the same direction in 3 rows and 3 columns or 2 rows and 2 columns may also be used as one pixel value in the fingerprint image, which is not specifically limited in this embodiment of the present application.

Alternatively, the color filter may be located in one or more of the plurality of directions, for example, if the color filter is placed in one of the directions, the fingerprint image formed by the fingerprint light signal in the direction is used for fingerprint anti-counterfeiting, such as anti-counterfeiting of 3D false fingerprint. Fingerprint images formed by the fingerprint optical signals in other directions are used for fingerprint identification, the images in the directions can be used for fingerprint anti-counterfeiting independently, and the images can be subjected to fingerprint identification after a clear fingerprint image is obtained through algorithm reconstruction. The color filters can be placed in a plurality of directions, and can be color filters of the same color or color filters of different colors.

Optionally, the color of the color filter is any one of red, green, blue, yellow, and white.

Optionally, the color filter may be placed in one or more of the light blocking layers, and the color filter may also be placed above the top metal layer of the chip.

In some embodiments of the present application, the fingerprint identification device may further include a transparent medium layer.

The transparent medium layer is used for connecting the micro-lens array, the light blocking layers and the pixel array.

For example, the transparent medium layer is transparent to the optical signal of the target wavelength band (i.e., the optical signal of the wavelength band required for fingerprint detection). For example, the transparent dielectric layer may be an oxide or a nitride. Optionally, the transparent dielectric layer may include multiple layers to achieve the functions of protection, transition, buffering, and the like, respectively. For example, a transition layer may be disposed between the inorganic layer and the organic layer to achieve a tight connection; a protective layer may be provided over the easily oxidizable layer to provide protection.

Optionally, the transparent medium layer may be a colored transparent medium layer, for example, the color of the transparent medium layer may be all green or all cyan, which is not specifically limited in this embodiment of the application.

As shown in fig. 10, the electronic device 400 may include a display 420, a plurality of fingerprint recognition units 430 in a fingerprint recognition device under the display, and a substrate 440, where a pixel array in the fingerprint recognition device and the substrate 440 may be referred to as a fingerprint sensor or an image sensor. Wherein the color filter 431 as described above is provided in the light blocking layer in the plurality of fingerprint recognition units 430. The fingerprint identification unit 430 may further include a transparent medium layer 432, as shown in fig. 10, the transparent medium layer 432 may be disposed between the second light-blocking layer and the third light-blocking layer to transmit an optical signal of a target wavelength band, so as to improve the quality of a fingerprint image. The transparent medium layer may also be disposed between the pixel array and the plurality of light blocking layers, and the transparent medium layer may also be disposed between the microlens array and the light blocking layers, which is not specifically limited in this embodiment of the application. Optionally, the transparent medium layer may be a colored transparent medium layer.

The fingerprint identification unit 430 may further include an optical filter layer for filtering out the optical signals in the non-target wavelength band to transmit the optical signals in the target wavelength band. For example, the transmittance of the optical filter layer for light in a target wavelength band may be greater than or equal to a preset threshold, and the cut-off rate for light in a non-target wavelength band may be greater than or equal to the preset threshold. For example, the preset threshold may be 80%. Alternatively, the optical filter layer may be a separately formed optical filter layer. For example, the optical filter layer may be formed by using blue crystal or blue glass as a carrier. For example, the optical filter layer may be an infrared cut filter for filtering an infrared light signal to transmit a visible light signal. The infrared cut-off filter can be arranged between the pixel array and the light blocking small holes in the bottom layer, and can also be arranged between a plurality of light blocking layers. The optical filter layer can also be arranged between the display screen and the fingerprint identification device, and if the infrared cut-off filter plate is arranged between the display screen and the fingerprint identification device. The embodiment of the present application does not limit this.

It should be understood that fig. 10 is only an example of the way of placing the color filter, and should not impose any limitation on the present application.

The embodiment of the application also provides electronic equipment which can comprise a display screen and the fingerprint identification device, wherein the fingerprint identification device is arranged below the display screen to realize optical fingerprint identification under the screen. The electronic device may be any electronic device having a display screen.

In some embodiments of the present application, there may or may not be a gap between the fingerprint recognition device and the display screen.

For example, there may be a gap of 0 to 1mm between the fingerprint recognition device and the display screen.

In some embodiments of the present application, the fingerprint recognition device may output the collected image to a special processor of a computer or a special processor of an electronic device, so as to perform fingerprint recognition.

It should be understood that the fingerprint recognition device of the embodiments of the present application may further include a memory, which may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. The non-volatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable PROM (EEPROM), or a flash Memory. The volatile Memory may be a Random Access Memory (RAM) which functions as an external cache. By way of example, but not limitation, many forms of RAM are available, such as Static random access memory (Static RAM, SRAM), dynamic random access memory (dynamic RAM, DRAM), Synchronous dynamic random access memory (Synchronous DRAM, SDRAM), Double Data Rate Synchronous dynamic random access memory (DDR SDRAM), Enhanced Synchronous SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), and Direct Rambus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

It should be understood that the specific examples in the embodiments of the present application are for the purpose of promoting a better understanding of the embodiments of the present application and are not intended to limit the scope of the embodiments of the present application.

It is to be understood that the terminology used in the embodiments of the present application and the appended claims is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of the present application. For example, as used in the examples of this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

Those of ordinary skill in the art will appreciate that the elements of the examples described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described above generally in terms of their functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the several embodiments provided in the present application, it should be understood that the disclosed system and apparatus may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present application.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or four or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially or partially contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: u disk, removable hard disk, read only memory, random access memory, magnetic or optical disk, etc. for storing program codes.

While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a fingerprint identification device, sets up in electronic equipment's display screen below, its characterized in that includes:

a micro lens array arranged below the display screen;

the light blocking layers are arranged below the micro lens array, and each light blocking layer in the light blocking layers is provided with at least one light passing small hole corresponding to each micro lens in the micro lens array;

the pixel array is arranged below the light blocking layers, the spatial sampling period P of pixels used for receiving fingerprint optical signals in the same direction in the pixel array is smaller than half of the spatial imaging period of the display screen, and each microlens in the microlens array converges the fingerprint optical signals in multiple directions, which are reflected or scattered by a finger above the display screen and then return, to multiple pixels in the pixel array respectively through a light-passing pore corresponding to each microlens;

the fingerprint light signals in the multiple directions are used for forming multiple fingerprint images, each fingerprint image in the multiple fingerprint images is subjected to low-pass filtering processing to form a first target fingerprint image, an average value of N rows and N columns of pixel values in the first target fingerprint image is used as one pixel value in a second target fingerprint image, N is a positive integer, and the second target fingerprint image is used for fingerprint identification.

2. The fingerprint recognition device of claim 1, wherein the spatial sampling period N P of the pixels in the second target fingerprint image is less than half of the spatial imaging period of the display screen.

3. The fingerprint recognition device of claim 1, wherein the spatial sampling period N P of the pixels in the second target fingerprint image is greater than or equal to half of a spatial imaging period of the display screen, and the fingerprint recognition device has a preset deflection angle relative to the display screen.

4. The fingerprint recognition device according to claim 3, wherein the fingerprint recognition device has a first direction, the first direction being parallel to an arrangement direction of the pixel array; the display screen is provided with a second direction, the second direction is parallel to the arrangement direction of pixels in the display screen, and an included angle between the first direction and the second direction is the preset deflection angle.

5. The fingerprint recognition device according to claim 4, wherein the preset deflection angle is in a range of-45 degrees to 45 degrees and is not equal to zero.

6. The fingerprint recognition device according to claim 4, wherein the preset deflection angle is inversely proportional to a spatial imaging period of the display screen.

7. The fingerprint identification device of any one of claims 1 to 6, wherein the spatial sampling period N P of pixels in the second target fingerprint image is less than 75 microns.

8. The fingerprint recognition device according to any one of claims 1 to 7, wherein each of the pixel arrays comprises a plurality of photosensitive areas, each of the plurality of photosensitive areas is located at a bottom of the light-passing aperture, and at least one of the plurality of photosensitive areas is located offset from a center of the microlens on which it is located.

9. The fingerprint identification device according to any one of claims 1 to 8, wherein one light-passing aperture is disposed in a top light-blocking layer of the plurality of light-blocking layers, and a plurality of light-passing apertures corresponding to the plurality of pixels are disposed in a bottom light-blocking layer of the plurality of light-blocking layers.

10. The fingerprint recognition device according to any one of claims 1 to 9, further comprising:

at least one color filter is located pixel array's top, the fingerprint light signal of a plurality of directions passes through the fingerprint image that forms behind the color filter is used for carrying on fingerprint anti-fake.

11. The fingerprint recognition device of claim 10, wherein the color filters in each of the plurality of directions comprise different color filters.

12. The fingerprint recognition device of claim 10, wherein the color filters in each of the plurality of directions comprise color filters of the same color.

13. The fingerprint recognition device according to any one of claims 10 to 12, wherein the color filter has a color of any one of the following colors:

red, green, blue, yellow, white.

14. The fingerprint recognition device according to any one of claims 1 to 13, further comprising:

and the infrared cut-off filter is positioned above the pixel array and used for filtering the infrared light signals so as to transmit the visible light signals.

15. The fingerprint recognition device according to any one of claims 1 to 14, further comprising:

and the transparent medium layer is used for connecting the micro-lens array, the light blocking layers and the pixel array.

16. The fingerprint recognition device of claim 15, wherein the transparent dielectric layer is a colored transparent dielectric layer.

17. The utility model provides a fingerprint identification device, sets up in electronic equipment's display screen below, its characterized in that includes:

a micro lens array arranged below the display screen;

the fingerprint optical signals in the multiple directions are used for forming multiple fingerprint images, an average value of N rows and N columns of pixel values in each fingerprint image in the multiple fingerprint images is used as one pixel value in a third target fingerprint image, the third target fingerprint image is subjected to low-pass filtering processing to form a fourth target fingerprint image, an average value of L rows and L columns of pixel values in the fourth target fingerprint image is used as one pixel value in a fifth target fingerprint image, and the fifth target fingerprint image is used for fingerprint identification, wherein L is a positive integer;

18. An electronic device, comprising:

a display screen; and

the fingerprint recognition device according to any one of claims 1 to 17, said fingerprint recognition device being disposed below said display screen to enable an off-screen optical fingerprint recognition.

19. The electronic device of claim 18, wherein a distance between the fingerprint recognition device and the display screen is 0 to 1 mm.