WO2020243935A1

WO2020243935A1 - Optical fingerprint recognition method and apparatus, and electronic device

Info

Publication number: WO2020243935A1
Application number: PCT/CN2019/090215
Authority: WO
Inventors: 张玮; 李顺展; 周飞; 曾红林
Original assignee: 深圳市汇顶科技股份有限公司
Priority date: 2019-06-05
Filing date: 2019-06-05
Publication date: 2020-12-10
Also published as: CN111052138A; CN111052138B

Abstract

The embodiments of the present application relate to an optical fingerprint recognition method and apparatus, and an electronic device. The optical fingerprint recognition apparatus comprises: an optical path guide structure and an optical fingerprint sensor, wherein the optical path guide structure is arranged between a display screen and the optical fingerprint sensor, so as to guide a returned optical signal formed by a finger above the display screen to the optical fingerprint sensor; a sensing array comprised in the optical fingerprint sensor is used to receive the returned optical signal and detect, according to the returned optical signal, a fingerprint image of the finger; and a first returned optical signal comprised in the returned optical signal is an optical signal which is obtained by means of a first optical signal being transmitted into the finger and then being transmitted out of the finger and passing through the display screen. According to the optical fingerprint recognition method and apparatus and the electronic device of the embodiments of the present application, obtaining a fingerprint image by using transmitted light that is transmitted out of the surface of a finger is not affected by whether the finger is in good contact with a surface of the electronic device, and therefore, an imaging effect is better, and the success rate of fingerprint recognition is increased.

Description

Method, device and electronic equipment for optical fingerprint identification

Technical field

This application relates to the field of biometric identification, in particular to methods, devices and electronic equipment for optical fingerprint identification.

Background technique

In recent years, smart phones have entered the era of full screens, and the screen ratio of mobile phones has become larger and larger. Under-screen fingerprint recognition technology has become a trend. Optical under-screen fingerprint technology has first entered commercial use. Domestic mainstream mobile phone manufacturers have released optical under-screen fingerprint machines. New models of under-screen fingerprint technology from international brand manufacturers are also being closely developed.

The current fingerprint technology under the optical screen is basically applied to self-luminous mobile phone screens such as Organic Light-Emitting Diode (OLED) and Active-matrix Organic Light-Emitting Diode (AMOLED) Above, the self-luminous screen pixels included in this type of screen are used as the light source. The light shines on the finger and is reflected by the finger, passes through the mobile phone screen and special optical lens, and is received by the sensor under the screen to realize fingerprint image collection and fingerprint recognition.

Summary of the invention

This application provides a method, device and electronic equipment for optical fingerprint identification, which can improve fingerprint identification efficiency.

In a first aspect, an optical fingerprint identification device is provided, which is suitable for electronic equipment with a display screen, and includes: an optical fingerprint sensor with a light path guide structure; wherein the light path guide structure is used to be arranged on the display screen and the optical fingerprint sensor. Between the fingerprint sensors to guide the first return light signal formed by the finger above the display screen to the optical fingerprint sensor; the optical fingerprint sensor is used to be arranged below the display screen, and includes A sensing array of optical sensing units, the sensing array is used to receive the first return light signal passing through the optical path guiding structure, and detect the fingerprint image of the finger according to the first return light signal; wherein The first return optical signal is the optical signal transmitted by the first optical signal into the finger, and then transmitted from the finger and passing through the display screen.

With reference to the first aspect, in an implementation of the first aspect, the first light signal is a light signal emitted by a light-emitting component toward the finger at a preset angle, wherein the light-emitting component is used to be arranged on the display The edges of the screen are arranged side by side with the display screen without blocking each other.

In combination with the first aspect and the foregoing implementation manners of the first aspect, in another implementation manner of the first aspect, the light-emitting component is configured to be disposed below a non-display area on the upper surface of the electronic device, and the light-emitting component is The first light signal emitted from the preset angle is irradiated to the finger touching the fingerprint detection area on the upper surface of the electronic device, and the fingerprint detection area is located in the display area on the upper surface of the electronic device.

Combining the first aspect and the foregoing implementation manners thereof, in another implementation manner of the first aspect, the light-emitting component includes a light source and a lens, the lens is located on the upper surface of the light source; the lens is used to converge the The first light signal emitted by the light source makes the first light signal illuminate the finger touching the fingerprint detection area.

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the light-emitting component includes a vertical cavity surface emitting laser, and the vertical cavity surface emitting laser is used to touch the fingerprint detection area. The finger emits the first light signal.

With reference to the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the first light signal emitted by the light-emitting component is infrared light or visible light.

With reference to the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the wavelength of the infrared light is 940 nm; or the wavelength of the visible light is 550 nm.

With reference to the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the light-emitting assembly includes a light source, and the position of the light source corresponds to the first area on the upper surface of the electronic device, so The position of the optical fingerprint sensor corresponds to the second area on the upper surface of the electronic device, the line connecting the center point of the first area and the center point of the second area is a first line segment, and the first line The segment is perpendicular to the edge of the electronic device.

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the value range of the first line segment is between 5 mm and 30 mm.

Combining the first aspect and the foregoing implementation manners thereof, in another implementation manner of the first aspect, the light-emitting assembly includes a first light source and a second light source, and the position of the optical fingerprint sensor corresponds to the upper surface of the electronic device The first light source corresponds to a third area on the upper surface of the electronic device, the second light source corresponds to a fourth area on the upper surface of the electronic device, and the center point of the third area corresponds to The line connecting the center point of the fourth area is a second line segment, and the line connecting the center point of the second area and the midpoint of the second line segment is a third line segment, and the third line segment is perpendicular to the The edge of electronic equipment.

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the value range of the third line segment is between 5 mm and 30 mm.

In combination with the first aspect and the foregoing implementation manners of the first aspect, in another implementation manner of the first aspect, a transparent cover is provided above the display screen, and the light-emitting assembly is provided under an edge area of the transparent cover; The transparent cover is used to provide a touch interface for the finger, and the first light signal emitted by the light-emitting component is transmitted into the finger from the transparent cover at the preset angle.

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the exit angle of the first light signal emitted by the light-emitting assembly on the upper surface of the transparent cover plate is less than or equal to the angle default value.

With reference to the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the preset angle value ranges from 1° to 20°.

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the preset angle is between 10° and 20°.

In combination with the first aspect and the foregoing implementation manners of the first aspect, in another implementation manner of the first aspect, the height of the incident position on the finger of the first light signal emitted by the light-emitting assembly from the transparent cover plate Less than or equal to the preset height value.

With reference to the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the preset height value is less than or equal to 5 mm.

In combination with the first aspect and the foregoing implementation manners of the first aspect, in another implementation manner of the first aspect, the transparent cover includes a first light-absorbing part, and the first light-absorbing part is used to absorb the The first part of the light in the first optical signal is used to prevent the first part of the light from being reflected on the surface of the transparent cover plate from being transmitted to the optical fingerprint sensor.

In combination with the first aspect and the foregoing implementation manners of the first aspect, in another implementation manner of the first aspect, the first light absorbing portion is provided in a non-display area on the upper surface of the transparent cover plate.

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the display screen includes conductive glass and a polarizer close to the transparent cover plate, and the light-emitting component is located between the conductive glass and the conductive glass. The edge of the light-emitting component, the conductive glass and the polarizer are not shielded from each other.

In combination with the first aspect and the foregoing implementation manners of the first aspect, in another implementation manner of the first aspect, a second light-absorbing part is provided between the light-emitting component and the conductive glass and the polarizer, and the second light-absorbing part The part is used to absorb the second part of the light in the first optical signal emitted by the light-emitting component, so as to prevent the second part of the light from being laterally transmitted to the conductive glass and the polarizer.

Combining the first aspect and the foregoing implementation manners thereof, in another implementation manner of the first aspect, the display screen includes a plurality of self-luminous display units, and the multiple self-luminous display units are used to display images; the light path The guiding structure is used for: guiding the second return light signal formed by the finger above the display screen to the optical fingerprint sensor; the sensing array of the optical fingerprint sensor is used for: receiving guidance through the optical path Structure of the second return light signal, and detect the fingerprint image of the finger according to the second return light signal; wherein, the second return light signal is at least part of the self-luminous display unit of the display screen. The second optical signal irradiates the finger and generates a reflected optical signal.

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the optical fingerprint sensor is used to detect the first fingerprint image of the finger according to the first return light signal, and Detecting a second fingerprint image of the finger according to the second return light signal.

With reference to the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the wavelength of the second optical signal is 550 nm.

With reference to the first aspect and the foregoing implementation manners of the first aspect, in another implementation manner of the first aspect, the device further includes: a control unit configured to control the at least The partly self-luminous display unit does not emit the second light signal, and when the at least part of the self-luminous display unit emits the second light signal, the light-emitting assembly is controlled not to emit the first light signal.

With reference to the first aspect and the foregoing implementation manners of the first aspect, in another implementation manner of the first aspect, the device further includes: a processor configured to obtain a first fingerprint image, where the first fingerprint image is Generated according to the first return light signal; when the first fingerprint image matches the preset fingerprint image, it is determined that the fingerprint recognition is successful; or, when the first fingerprint image does not match the preset fingerprint image When the fingerprint recognition fails.

With reference to the first aspect and the foregoing implementation manners of the first aspect, in another implementation manner of the first aspect, the device further includes: a processor, and the processor is further configured to: obtain a first fingerprint image, the first fingerprint The image is generated based on the first return light signal; a second fingerprint image is acquired, and the second fingerprint image is generated based on the second return signal light; in the first fingerprint image and the second fingerprint If at least one fingerprint image in the image matches a preset fingerprint image, it is determined that the fingerprint recognition is successful; or, when the first fingerprint image and the second fingerprint image do not match the preset image, it is determined that the fingerprint recognition fails .

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the optical path guiding structure includes an optical lens, and the optical lens is disposed above the optical fingerprint sensor for passing through the optical fingerprint sensor. The return light signal of the display screen is converged to the sensing array of the optical fingerprint sensor.

Combining the first aspect and the foregoing implementation manners thereof, in another implementation manner of the first aspect, the first return light signal is infrared light, the second return light signal is visible light, and the optical lens responds to infrared light. It can image and image visible light without aberration.

Combining the first aspect and the foregoing implementation manners thereof, in another implementation manner of the first aspect, the light path guiding structure includes an optical collimator having a plurality of collimating units or a microhole array, and the optical collimator is used for For transmitting the return light signal passing through the display screen to the corresponding optical sensing unit in the sensing array of the optical fingerprint sensor through the plurality of collimating units or microhole arrays; or, the optical path guides The structure includes a microlens array with a plurality of microlenses and a light blocking layer with a plurality of microholes. The microlens array is used to focus the return light signals passing through the display screen to the microlenses respectively. The microholes corresponding to the light blocking layer are transmitted to the corresponding optical sensing units in the sensing array of the optical fingerprint sensor through the microholes.

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the device further includes: a filter located above the optical fingerprint sensor, and the filter is used to filter out Optical signals other than the first return optical signal and the second return optical signal.

In combination with the first aspect and the foregoing implementation manners, in another implementation manner of the first aspect, the first return optical signal is infrared light with a wavelength of 940 nm, and the second return optical signal is visible light with a wavelength of 550 nm. The filter is at least used to filter out light whose wavelength is not equal to 940nm and 550nm.

Therefore, the optical fingerprint identification device of the embodiment of the present application includes an optical fingerprint sensor that receives the light signal transmitted from the finger. After the light is incident on the finger, the light transmitted from the surface of the finger is at the valley line and There is a difference in the ridge part, and the fingerprint image can be generated by this difference, and this difference can not be affected by whether the finger is in good contact with the surface of the electronic device, that is, it is basically not affected by the dry finger, so the imaging The effect is better and the fingerprint image obtained is clearer, which can further improve the success rate of fingerprint recognition.

In a second aspect, an electronic device is provided, including: the optical fingerprint identification device in the first aspect or each of its possible implementations.

In a third aspect, a fingerprint identification method is provided, which is applicable to the optical fingerprint identification device in the first aspect or each of its possible implementations. The method includes: acquiring a first fingerprint image, where the first fingerprint image is Generated according to the first return light, the first return light is a light signal transmitted into and out of the finger by a first light signal; fingerprint identification is performed according to the first fingerprint image.

With reference to the third aspect, in an implementation of the third aspect, the performing fingerprint recognition according to the first fingerprint image includes: if the first fingerprint image matches a preset fingerprint image, determining the fingerprint recognition Success; or, if the first fingerprint image does not match the preset fingerprint image, it is determined that the fingerprint recognition fails.

With reference to the third aspect and the foregoing implementation manners, in another implementation manner of the third aspect, the method further includes: acquiring a second fingerprint image, the second fingerprint image being generated according to the second return light, and The second return light is the light signal reflected after the finger is illuminated by the second light signal; the fingerprint recognition based on the first fingerprint image includes: if the first fingerprint image and the second fingerprint image At least one fingerprint image matches the preset fingerprint image, and it is determined that the fingerprint recognition is successful.

With reference to the third aspect and the foregoing implementation manners, in another implementation manner of the third aspect, the performing fingerprint recognition according to the first fingerprint image includes: if the first fingerprint image and the second fingerprint image are The fingerprint images do not match the preset image, and it is determined that the fingerprint recognition fails.

Description of the drawings

Fig. 1 is a top view of the structure of an electronic device according to an embodiment of the present application.

Fig. 2 is a side view of the structure of an electronic device according to an embodiment of the present application.

Fig. 3 is a schematic diagram of guiding an optical path through a collimator according to an embodiment of the present application.

Fig. 4 is a schematic diagram of guiding an optical path through a lens according to an embodiment of the present application.

Fig. 5 is a schematic diagram based on the principle of reflection imaging according to an embodiment of the present application.

Fig. 6 is a fingerprint image obtained based on reflection imaging according to an embodiment of the present application.

FIG. 7 is a schematic diagram of the principle of a dry finger based on reflection imaging according to an embodiment of the present application.

Fig. 8 is a fingerprint image obtained based on reflection imaging of a dry finger according to an embodiment of the present application.

Fig. 9 is a schematic diagram of vertical light transmitted from the surface of a finger according to an embodiment of the present application.

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

Fig. 11 is a fingerprint image obtained based on the principle of reflected light according to an embodiment of the present application.

Fig. 12 is a fingerprint image obtained based on the principle of transmitted light according to an embodiment of the present application.

Fig. 13 is a schematic diagram of a light emitting angle of a light emitting component according to an embodiment of the present application.

Fig. 14 is a schematic diagram of a position of a light source corresponding to a transparent cover plate included in a light emitting assembly according to an embodiment of the present application.

Fig. 15 is a schematic diagram of a finger touch position according to an embodiment of the present application.

Fig. 16 is a schematic diagram showing the positions of two light sources corresponding to the transparent cover plate included in the light-emitting assembly according to the embodiment of the present application.

Fig. 17 is another schematic diagram of a finger touch position according to an embodiment of the present application.

Fig. 18 is another schematic diagram of a finger touch position according to an embodiment of the present application.

Fig. 19 is a schematic diagram of a first light-absorbing part provided in a transparent cover according to an embodiment of the present application.

Fig. 20 is another schematic diagram of an electronic device according to an embodiment of the present application.

FIG. 21 is a schematic diagram of an optical fingerprint identification device according to an embodiment of the present application.

Fig. 22 is a curve of the focus shift of the polychromatic light of the optical lens according to the embodiment of the present application.

FIG. 23 is a graph of the transmittance of a filter according to an embodiment of the present application to light of different wavelengths.

FIG. 24 is a schematic flowchart of a fingerprint identification method according to an embodiment of the present application.

Detailed ways

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

It should be understood that the embodiments of this application can be applied to optical fingerprint systems, including but not limited to optical fingerprint identification systems and medical diagnostic products based on optical fingerprint imaging. The embodiments of this application only take optical fingerprint systems as an example for description, but should not The embodiments of the application constitute any limitation, and the embodiments of the present application are also applicable to other systems using optical imaging technology.

As a common application scenario, 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. Alternatively, the fingerprint identification device may be partially or fully integrated into the display screen of the electronic device, thereby forming an in-display optical fingerprint system.

FIG. 1 and FIG. 2 show two structural diagrams of electronic devices to which the embodiments of this application can be applied. FIG. 1 is a top view, and FIG. 2 is a side view. 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 below the display screen 120. The optical fingerprint device 130 includes an optical fingerprint sensor, and the optical fingerprint sensor includes a sensing array 133 with a plurality of optical sensing units 131, and the area where the sensing array is located or its sensing area is the fingerprint detection area 103 corresponding to 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. In an alternative embodiment, 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 on the edge of the electronic device 10, and the optical fingerprint device 130 can be designed through the optical path. At least part of the optical signal of the display area 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.

It should be understood that the area of the fingerprint detection area 103 may be different from the area of the sensing array of the optical fingerprint device 130. For example, through the optical path design of lens imaging, the reflective folding optical path design, or other optical path design such as light convergence or reflection, it can make The area of the fingerprint detection area 103 corresponding to the optical fingerprint device 130 is larger than the area of the sensing array of the optical fingerprint device 130. In other alternative implementations, if for example, light collimation is used for light path guidance, the fingerprint detection area 103 corresponding to the optical fingerprint device 130 may also be designed to be substantially the same as the area of the sensing array of the optical fingerprint device 130.

Therefore, when the user needs to unlock the electronic device or perform other fingerprint verification, he only needs to press his finger on the fingerprint detection area 103 located on the display screen 120 to realize fingerprint input. Since fingerprint detection can be implemented in the screen, the electronic device 10 adopting the above structure does not need to reserve space on the front side to set fingerprint buttons (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 It basically extends to the front of the entire electronic device 10.

As an optional implementation, as shown in FIG. 2, 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 And 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 optical detector 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 filter layer, a light guide layer or Optical path guiding structure and other optical elements, the filter layer can be used to filter out the ambient light penetrating the finger, and the light guiding layer or optical path guiding structure is mainly used to guide the light returned from the finger to the sensing array Optical inspection.

In terms of specific implementation, the optical assembly 132 and the light detecting part 134 may be packaged in the same optical fingerprint component. For example, 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 in the above chip.

Among them, the light guide layer or light path guiding structure of the optical component 132 has multiple implementation schemes. For example, as shown in FIG. 3, the light guide layer of the optical component 132 may be specifically a collimator fabricated on a semiconductor silicon wafer. The Collimator layer has a plurality of collimator units or micro-hole arrays. The collimator unit can be specifically a small hole. Among the reflected light reflected from the finger, the light that is perpendicularly incident on the collimator unit can pass through and It is received by the optical sensor unit below it, and the light with too large incident angle is attenuated by multiple reflections inside the collimating unit, so each optical sensor unit can basically only receive the fingerprint pattern directly above it. The light is reflected, so that the sensor array can detect the fingerprint image of the finger.

In another embodiment, 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, for example, As shown in FIG. 4, the optical component 132 may include a lens for condensing the reflected light reflected from the finger to the sensing array of the light detecting portion 134 below it, so that the sensing array can perform based on the reflected light. Imaging to obtain a fingerprint image of the finger. Optionally, the optical lens layer may also be formed with a pinhole or an aperture stop 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 to improve the optical fingerprint device 130 fingerprint imaging effect.

In other embodiments, 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-lens, which may be formed by a semiconductor growth process or Other processes are formed above the sensing array of the light detection part 134, and each microlens can correspond to one of the sensing units of the sensing array. In addition, other optical film layers may be formed between the microlens layer and the sensing unit, such as a dielectric layer or a passivation layer. More specifically, a barrier with microholes may also be formed between the microlens layer and the sensing unit. Optical layer, wherein 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 allow the light corresponding to the sensing unit to pass through the The micro lens is converged into the micro hole and is transmitted to the sensing unit through the micro hole to perform optical fingerprint imaging.

It should be understood that several implementation solutions of the above-mentioned light path guiding structure can be used alone or in combination. For example, a microlens layer can be further provided under the collimator layer or the optical lens layer. Of course, when the collimator layer or the optical lens layer is used in combination with the microlens layer, the specific laminated structure or optical path may need to be adjusted according to actual needs.

Optionally, in some embodiments, the optical fingerprint device 130 may include only one optical fingerprint sensor. At this time, the fingerprint detection area 103 of the optical fingerprint device 130 has a small area and a fixed position. Therefore, when the user performs fingerprint input It is necessary to 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.

In other alternative embodiments, 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 of the plurality of optical fingerprint sensors The areas collectively constitute the fingerprint detection area 103 corresponding to the optical fingerprint device 130. In other words, the fingerprint detection area 103 corresponding to 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 It extends to the main area of the lower half of the display screen, that is, extends to the area where the finger is habitually pressed, so as to realize the blind fingerprint input operation. Alternatively, when the number of optical fingerprint sensors is sufficient, the fingerprint detection area 130 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.

It should be understood that, in specific implementation, the electronic device 10 further includes a transparent cover 110, or referred to as a transparent protective cover 110. The cover 110 may be a glass cover or a sapphire cover, which is located on the display screen 120. And cover the front of the electronic device 10. Because, in the embodiment of the present application, the so-called finger pressing on the display screen 120 actually refers to pressing the cover 110 above the display 120 or covering the surface of the protective layer of the cover 110.

It should be understood that the display screen 120 in the embodiment of the present application may adopt a display screen with a self-luminous display unit, such as an organic light-emitting diode (Organic Light-Emitting Diode, OLED) display screen or a micro-LED (Micro-LED) display screen . Taking an OLED display screen as an example, the optical fingerprint device 130 can use the display unit (ie, an 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 on 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 passes through the finger 140. Internal scattering forms scattered light.

In other embodiments, 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. In this case, 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. Taking a liquid crystal display with a backlight module and a liquid crystal panel as an example, in order to support the under-screen fingerprint detection of the liquid crystal display, the optical fingerprint system of the electronic device 10 may also include an excitation light source for optical fingerprint detection. The excitation light source may specifically be an infrared light source or a light source of non-visible light of a specific wavelength, which may be arranged under the backlight module of the liquid crystal display or in the edge area under the protective cover of the electronic device 10, and the The optical fingerprint device 130 can be arranged under the edge area of the liquid crystal panel or 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 in the backlight module. Under the group, and the backlight module is designed to allow the fingerprint detection light to pass through the liquid crystal panel and the backlight module and reach the optical fingerprint device 130 through openings or other optical designs on the film layers such as diffuser, brightness enhancement film, and reflective film. .

In other alternative implementations, the display screen 120 may also be a non-self-luminous display screen, such as a backlit liquid crystal display screen; in this case, the optical detection device 130 cannot use the display screen 120 The display unit is used as an excitation light source, so it is necessary to integrate an excitation light source inside the optical detection device 130 or set an excitation light source outside it to achieve optical fingerprint detection. When the optical fingerprint device 130 is used, a built-in light source or an external light source is used to provide When performing fingerprint detection of optical signals, the detection principle is consistent with the description of the self-luminous display above.

It should be understood that, for ease of description, the above-mentioned reflected light and scattered light are collectively referred to as reflected light. Since the ridge and valley of the fingerprint have different light reflection capabilities, the reflected light 151 from the fingerprint ridge and the generated light 152 from the fingerprint ridge have different light intensities. After the reflected light passes through the optical component 132, It is received by the sensing 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.

Specifically, FIG. 5 shows a schematic diagram based on the principle of reflected light imaging. As shown in Figure 5, it is assumed that the surface of the mobile phone is a glass cover, and the finger touches the surface of the glass cover of the mobile phone during fingerprint recognition. The fingerprint ridge line of the finger can make good contact with the surface, and the fingerprint valley line of the finger exists on the surface. A void, the void is air.

In addition, as shown in FIG. 5, it is also assumed here that the light L1 irradiated to the finger through the glass cover is uniform. According to the law of optical refraction and reflection, when the light L1 irradiates the finger, the fingerprint ridge line is in good contact, and the refractive index of the finger and the glass cover is similar, so the light L11 transmitted into the finger is more, and the reflected light L21 is more. However, there is an air gap at the valley line. Due to the large difference in refractive index between the air and the glass cover, the light L12 transmitted into the finger is less, and the reflected light L22 on the surface of the cover is more, and there may be a small part The light L23 reflected from the surface of the fingerprint valley forms a contrast signal between the fingerprint valley ridges, and then a fingerprint image can be formed, for example, the fingerprint image shown in FIG. 6.

However, in practical applications, due to the problem of dry fingers in the principle of optical fingerprints using reflective imaging, the fingerprint image may be unclear. Dry fingers mean that there is less oil and sweat on the surface of the fingers. For example, currently about 10% to 20% of people have dry fingers. In addition, the general population will also turn into dry fingers in special situations, such as after washing hands or under low temperature conditions. , Will cause the fingers to become dry.

Comparing the state in which the finger is in good contact with the surface of the touch phone in FIG. 5, FIG. 7 shows a schematic diagram of the vertical direction light when the finger touches the surface of the phone when the finger is dry. As shown in Figure 7, in the dry finger state, when the finger touches the surface of the phone, the fingerprint ridge line and the surface are not in good contact, and there is an air gap between the fingerprint ridge line and the phone surface; and the fingerprint valley line and the phone surface are also There is an air gap, which will cause the contrast of the reflected light imaging of the two to decrease or even completely disappear. That is to say, imaging depends on the difference of reflected light, but the signal contrast of this part is very low, so the imaging quality is poor. For example, as shown in Figure 8, in the dry finger state, the optical fingerprint cannot obtain a good signal, and the fingerprint image It is very unclear, this will lead to a serious decrease in the success rate of unlocking.

Therefore, the embodiments of the present application provide an optical fingerprint identification device, which can improve fingerprint identification efficiency.

Specifically, the optical fingerprint identification device is suitable for electronic equipment with a display screen, and includes: an optical fingerprint sensor located below the display screen; the optical fingerprint sensor is used to receive a first return light signal, and the first return light signal is a first A light signal is transmitted into the finger, and then transmitted from the finger and passed through the display screen. The first return light signal is used to obtain the first fingerprint image of the finger.

When the finger performs fingerprint recognition, the finger touches the fingerprint detection area on the upper surface of the electronic device, the first light signal is transmitted into the finger, and the first return light signal is transmitted from the surface of the finger. Wherein, the first light signal propagates in the finger after being transmitted into the finger, for example, reflection, refraction, or scattering may occur in the finger. Because the shape of the valley line and the ridge line of the fingerprint surface of the finger are different, the first return light signal that can be transmitted from the finger surface is different in the valley line and the ridge line of the fingerprint, for example, the first return at the valley line position The intensity of the optical signal will be weaker than the first return optical signal transmitted from the ridge line position. Based on this difference, a fingerprint image can be generated.

For example, as shown in FIG. 9, the first light signal transmitted into the finger propagates inside the finger. Here, the light perpendicular to the valley line and the ridge line of the fingerprint is taken as an example for description. Since the fingerprint valley line and the ridge line have different structures, for light in the vertical direction, generally, the light L21 that can irradiate the valley line vertically is less than the light L11 that can irradiate the ridge line vertically. In addition, take the optical signal transmitted from the finger surface in the vertical direction as an example. Here, the light L11 transmitted from the ridge line and then transmitted vertically into the electronic device is called light L12, and the light L21 transmitted from the valley line and transmitted vertically into the electronic device is called light L22, because the light L21 and The difference in L11 and the difference between the valley line and the ridge line, so the light L22 is usually less than the light L12.

Therefore, the light transmitted from the surface of the finger is different in the valley line and the ridge line. The fingerprint image can be generated by this difference, and this difference can not be affected by whether the finger is in good contact with the surface of the electronic device. That is, it is basically not affected by dry fingers, so the imaging effect is better, the fingerprint image obtained is clearer, and the success rate of fingerprint recognition is improved.

The optical fingerprint identification device of the embodiment of the present application will be described in detail below in conjunction with specific embodiments.

Specifically, FIG. 10 shows a schematic diagram of an electronic device 200 according to an embodiment of the present application. As shown in FIG. 10, the electronic device 200 includes: an optical fingerprint identification device 240 and a display screen 220, wherein the optical fingerprint identification device 240 is located below the display screen 220. Specifically, the optical fingerprint identification device 240 may include an optical fingerprint sensor disposed below the display screen; the optical fingerprint sensor is used to receive a first return light signal, and the first return light signal is the first light signal transmitted into the finger. , And then a light signal transmitted from the finger and passing through the display screen, and the first return light signal is used to obtain a first fingerprint image of the finger. For example, the optical fingerprint sensor includes a sensing array with a plurality of optical sensing units, the sensing array is used to receive the first return light signal passing through the optical path guiding structure, and detect the fingerprint image of the finger according to the first return light signal .

In addition, the optical fingerprint identification device 240 may further include: an optical path guiding structure, the optical path guiding structure is configured to be arranged between the display screen 220 and the optical fingerprint sensor to form the second finger on the display screen 220 A return optical signal is guided to the optical fingerprint sensor.

The optical fingerprint identification device 240 in the embodiment of the present application may be disposed inside the electronic device 200, where the electronic device 200 may be the electronic device 10 described above. For example, the optical fingerprint identification device 240 may be arranged on the front or back of the electronic device, or may be arranged under the display screen of the electronic device, or arranged around the display screen, for example, at the bottom of the display screen.

For ease of description, the embodiment of the present application takes the optical fingerprint identification device 240 disposed below the display screen 220 of the electronic device 200 as an example for description. Correspondingly, when performing fingerprint recognition, the finger touches the upper part of the display screen 220, that is, touches the fingerprint detection area on the upper surface of the electronic device 200. That is, the optical fingerprint identification device in the embodiment of the present application is an under-screen fingerprint identification device.

It should be understood that the optical fingerprint identification device 240 of the embodiment of the present application may correspond to the optical fingerprint device 130 in the electronic device 10, wherein the optical fingerprint sensor included in the optical fingerprint device 240 may correspond to the light detection part of the electronic device 10. 134, the optical path guiding structure included in the optical fingerprint device 240 may correspond to the optical component 132 in the electronic device 10, for example, corresponding to the optical path guiding structure included in the optical component 132; in addition, the display screen 220 may correspond to FIG. 1 For the sake of brevity, the display screen 120 in FIG. 2 will not be repeated here.

For example, the display 220 in the embodiment of the present application takes a self-luminous display as an example for description. Specifically, the display screen 220 may also include a plurality of self-luminous display units, or an array of self-luminous display units. Among them, the self-luminous display unit can be used to display images.

Since the self-luminous display unit of the display screen 220 can emit light, the first light signal in the embodiment of the present application can be obtained by the self-luminous display unit of the display screen 220.

Alternatively, the first optical signal in the embodiment of the present application may also be obtained by emitting light from other light sources. Since the influence of reflected light should be avoided as much as possible in the process of imaging using transmitted light, it can be considered to avoid the influence of reflected light by reasonably setting the position of the light source that emits the first light signal.

Optionally, as shown in FIG. 10, the electronic device 200 further includes a light emitting component 230 for emitting the first light signal. For example, the light emitting component 230 is used for emitting the first light signal to the finger at a preset angle. The first light signal is irradiated to the finger touching the fingerprint detection area on the upper surface of the electronic device 200, and the fingerprint detection area is located in the display area on the upper surface of the electronic device 200.

. Specifically, in order to avoid the influence of reflected light, the light-emitting component 230 may be arranged on the edge of the display screen 220 so as not to block each other.

For example, the light-emitting assembly 230 may be disposed under the non-display area of the upper surface of the electronic device 200. In other words, the light-emitting component 230 can be arranged in the frame of the electronic device 200 so as not to affect the display image of the surface display 220.

For another example, the electronic device 200 may further include a transparent cover 210 which is located above the display screen 220 and also located above the light-emitting assembly 230. The transparent cover 210 is used to provide a touch interface for fingers, that is, the transparent cover 210 is the structure of the upper surface of the electronic device 200.

It should be understood that the transparent cover 210 may correspond to the cover 110 in the above-mentioned electronic device 10, for the sake of brevity, it will not be repeated here.

The transparent cover 210 is disposed above the display screen 220 and the light-emitting assembly 230, so that the light emitted by the light-emitting assembly 230 reaches the finger only after being transmitted by the transparent cover 210, thereby ensuring the first light signal transmitted to the finger Strength and directionality are better,

For example, Figure 11 shows a fingerprint image obtained based on reflected light imaging. As shown in Figure 11, the central area of the fingerprint image has a weak signal due to poor contact. For example, the fingerprint image may not be affected by dry fingers. Clear. FIG. 12 shows a fingerprint image obtained based on transmitted light imaging in the same state as FIG. 11. For example, FIG. 12 may be a first fingerprint image obtained by the electronic device 200 shown in FIG. 10. As shown in Fig. 12, in the same state as Fig. 11, the transmitted light imaging is less affected by the contact situation, so the imaging is clearer.

It should be understood that, considering the effect of light transmission, the light-emitting assembly 230 of the embodiment of the present application is preferably a light source with strong directivity. For example, the light-emitting assembly 230 may include a component for emitting laser light, such as a laser, or a vertical cavity surface emitting Laser (vecsel), the laser included in the light-emitting assembly 230 is used to emit the first light signal; or, the light-emitting assembly may also include a light-emitting diode (Light Emitting Diode, LED) light source, through which the LED light source emits light and can be emitted A lens is arranged above the light source in the component 230 to achieve the purpose of condensing light, thereby reducing the spread of stray light.

For example, as shown in FIG. 13, the light-emitting assembly 230 may include a light source 231 and a lens 232, the lens 232 is located on the upper surface of the light source 231; the lens 232 is used to converge the first light signal emitted by the light source 231, so that A light signal illuminates the finger touching the fingerprint detection area at a preset angle. For example, the lens 232 converges the first light signal toward the position where the finger touches the upper surface of the electronic device.

Optionally, the light-emitting component 230 in the embodiment of the present application may emit visible light, or may also emit invisible light, that is, the first light signal may be visible light, or the first light signal may also be invisible light, for example, the first light An optical signal can also be infrared light.

For example, when the first optical signal is visible light, visible light in the 550 nm wavelength band may be selected, or visible light in other wavelength bands may also be selected.

For another example, when the first optical signal is invisible light, for example, the first optical signal may be infrared light, and infrared light in the 940 nm band may be selected, or infrared light in other wavelength bands may also be selected.

Optionally, in order to avoid that the first light signal transmitted to the finger needs to penetrate the tissue too much, resulting in rapid attenuation of the light intensity, the relevant parameters of the light signal emitted by the light-emitting component 230 need to be adjusted.

For example, as shown in FIG. 13, the exit angle θ of the light emitted by the light-emitting assembly 230 on the upper surface of the transparent cover 210 can be set to be less than or equal to a preset angle value, where the preset angle value can be based on actual applications. Make settings. For example, the effect of the first light signal transmitted into the finger can be considered. If the preset value of the angle is too large, it will cause too much tissue to pass through after being transmitted into the finger, and too much light intensity attenuation. For example, usually, the value range of the preset angle can be set to 1° to 20°, or it can also be set to be between 10° and 20°.

In addition, as shown in FIG. 13, it is also possible to set the incident position of the light emitted by the light-emitting component 230 on the finger and the height H of the transparent cover 210 to be less than or equal to the preset height value. , The height preset value can also be set according to actual applications. For example, consider the effect of the first light signal transmitted into the finger. If the preset height is too large, it will cause too much tissue to pass through after being transmitted into the finger, and the light intensity attenuation is too much; but it cannot be set too small. , Will also affect the intensity of the first optical signal. Therefore, usually the preset height can be set to be less than or equal to 5 mm.

By setting the exit angle from the transparent cover 210 and the height of the incident finger, it is possible to avoid the problem that the first light signal needs to penetrate the tissue too much, resulting in rapid light intensity attenuation.

Optionally, the light-emitting assembly 230 of the embodiment of the present application may include at least one light source, and by setting the light source in different positions, different imaging effects may be obtained. Wherein, each light source in the at least one light source in the embodiment of the present application may be a point light source, for example, an LED lamp; or each light source may refer to a group of light sources composed of multiple point light sources, for example, an LED lamp group. The intensity of each light source can be set according to actual needs.

Optionally, as an embodiment, the light-emitting assembly 230 may include only one light source. FIG. 14 shows a schematic diagram of the position of one light source included in the light-emitting assembly 230 corresponding to the position of the transparent cover plate. As shown in FIG. 14, for ease of description, the area where a light source included in the light-emitting assembly 230 corresponds to the upper surface of the transparent cover 210 is referred to as the first area 201, and the optical fingerprint sensor in the optical fingerprint identification device 240 The area corresponding to the upper surface of the transparent cover 210 is called the second area 202.

When there is only one light source, the light source can be set according to the position shown in FIG. 14, that is, the first area 201 is located directly below the second area 202. Specifically, the distance between the first area 201 and the second area 202 may be referred to as a first line segment l ₁ , for example, as shown in FIG. 14; or, the center point of the first area 201 and the second area The line connecting the center points of the two regions 202 is called the first line segment l ₁ . The first line segment _{11 is} perpendicular to the edge of the electronic device, or the first line segment _{11 is} perpendicular to the lower edge of the transparent cover 210.

Optionally, the value range of the first line segment l ₁ can be between 5mm and 30mm, which can avoid the increase of finger tissue that needs to be transmitted when the distance is too long, which will affect the final imaging effect, and also avoid the distance from being too short It interferes with the structure of the mobile phone.

However, as shown in FIG. 15, when the finger performs fingerprint recognition, when the finger touches the fingerprint detection area of the transparent cover, the joint part of the finger may be just above the light source. Since there are more tissues in the finger joints, light needs to pass through more finger tissues, so the light signal attenuates greatly, which may affect the image quality.

Therefore, as another embodiment, the light-emitting assembly 230 may further include multiple light sources. For example, the light-emitting assembly 230 may include two light sources. Optionally, here, it is taken as an example that the multiple light sources include two light sources, and the two light sources are a first light source and a second light source, respectively.

FIG. 16 shows a schematic diagram of the position corresponding to the transparent cover when the light-emitting assembly of the embodiment of the present application includes two light sources. Specifically, the area of the optical fingerprint sensor corresponding to the upper surface of the transparent cover 210 is referred to as the second area 202, and the area of the first light source corresponding to the upper surface of the transparent cover 210 is referred to as the third area 203. The area of the second light source corresponding to the upper surface of the transparent cover 210 is called the fourth area 204. Wherein, the third area 203 is located at the lower left of the second area 202, and the fourth area 204 is located at the lower right of the second area 202.

Specifically, the line between the third area 203 and the fourth area 204 is called the second line segment l ₂ , for example, as shown in FIG. 16; or, the center point of the third area 203 and the first The line connecting the center points of the four regions 204 is called the second line segment l ₂ . In addition, the distance from the second area 202 to the second line segment l ₂ can also be referred to as the third line segment l ₃ , for example, as shown in FIG. 16; or, the center point of the second area 202 can also be The line connecting the midpoints of the second line segment l ₂ is the third line segment l ₃ . The third line segment _{13 is} perpendicular to the edge of the electronic device, or the third line segment _{13 is} perpendicular to the lower edge of the transparent cover 210.

Optionally, the value range of the third line segment is between 5mm and 30mm, which can avoid the increase of finger tissue that needs to be transmitted when the distance is too long, which will affect the final imaging effect, and also avoid the distance between the mobile phone and the structure of the phone when the distance is too short. Interference.

For the case where the left and right light sources are set, as shown in Fig. 17, when the finger presses the transparent cover 210 laterally from the left side of the surface, the second light source on the right side has better illumination effect, because fewer fingers need to penetrate Similarly, as shown in FIG. 18, when a finger presses the transparent cover 210 laterally from the right side of the surface, the first light source on the left has a better illumination effect because there are fewer fingers to penetrate. In addition, when the finger is pressed from the forward direction, for example, the finger pressing direction as shown in FIG. 15, at this time, both the first light source and the second light source have a better illumination effect. For a light source, the imaging effect is better. Therefore, setting multiple light sources in different directions and positions can change the image quality under different pressing postures.

Optionally, as another embodiment, the light-emitting assembly 230 may further include more than two light sources. For example, the light-emitting assembly 230 may also include a light source array. For example, all the light sources of the light source array can be arranged side by side at the bottom frame position of the electronic device.

For another example, the light-emitting component 230 may also be a light-emitting strip. For example, a light-emitting strip is arranged on the bottom frame of the electronic device, and the light emitted by the light-emitting strip is strip-shaped (or called a strip).

In the embodiment of the present application, considering that the light emitted by the light-emitting assembly 230 is transmitted out of the transparent cover 210, it may also be reflected when irradiated on the surface of the transparent cover 210. The reflected light may affect the optical fingerprint identification device 240. Imaging, or may also affect the display screen 220 to display images. Therefore, a light-absorbing part can be provided on the surface of the transparent cover 210 in front of the transmissive light source. For example, a light-absorbing material can be plated on the surface of the transparent cover 210 to prevent the reflected light from propagating through the transparent cover 210 to the optical fingerprint recognition transpose 240. Affect imaging.

Specifically, the transparent cover 210 may include a first light-absorbing part 211, for example, the first light-absorbing part 211 may be a light-absorbing substance plated on the surface of the transparent cover 210. Fig. 19 shows a schematic diagram of a first light-absorbing part provided in a transparent cover according to an embodiment of the present application. As shown in FIG. 19, the upper surface or the lower surface of the transparent cover 210 may be provided with a first light absorbing part 211, and the first light absorbing part 211 may be used to absorb the first part of the light emitted by the light-emitting assembly 230, so that the The first part of light cannot be transmitted to the optical fingerprint recognition device 240 after being reflected on the upper surface of the transparent cover 210. For example, the first part of light can be prevented from being reflected on the upper surface of the transparent cover 210 and transmitted to the optical fingerprint sensor.

Optionally, since the first light-absorbing part 211 is a light-absorbing material, in order not to affect the normal display image of the electronic device, the first light-absorbing part 211 may be disposed on the non-display area of the upper surface or the lower surface of the transparent cover 210 , So that the display area on the surface of the electronic device may not be affected by the first light absorption part 211.

It should be understood that the display screen 220 included in the electronic device 200 of the embodiment of the present application may also include conductive glass and a polarizer (Polarizer). Specifically, Fig. 20 shows another schematic diagram of an electronic device 200 according to an embodiment of the present application. As shown in FIG. 20, the display screen 220 of the electronic device 200 further includes: conductive glass 221 and a polarizer 222 located between the transparent cover 210 and the display screen 220.

Wherein, the position setting between the conductive glass 221 and the polarizer 222 and the light-emitting assembly 230 can refer to the relationship between the display screen 220 and the light-emitting assembly 230. Specifically, the light emitting component 230 is located at the edge of the conductive glass 221 and the light emitting component 230; the light emitting component 230 and the conductive glass 221 do not block each other; the light emitting component 230 and the polarizer 222 do not block each other.

It should be understood that the conductive glass 221 in the embodiment of the present application may be Indium-Tin Oxide (ITO) conductive glass, but the embodiment of the present application is not limited thereto.

Optionally, the electronic device 200 of the embodiment of the present application may further include: a second light absorbing part 270, wherein the second light absorbing part 270 is located between the light emitting component 230 and the conductive glass 221, and the light emitting component 230 and the conductive glass 221 Between the polarizers 222, for example, as shown in FIG. 20.

Specifically, the second light absorption portion 270 can be used to absorb the second part of the light emitted by the light-emitting assembly 230 to prevent the second part of the light from being laterally transmitted into the conductive glass 221 and the polarizer 222. In this way, the light-absorbing material is filled in front of the light source propagation, which can prevent the laterally propagating light image imaging through the conductive glass and the polarizer.

It should be understood that while the electronic device 200 of the embodiment of the present application generates a fingerprint image through the principle of transmission imaging, it does not affect the process of acquiring a fingerprint image based on the principle of reflection. Therefore, when a finger touches the fingerprint detection area on the transparent cover 210, the electronic device 200 can acquire a fingerprint image based on the principle of transmission imaging or the principle of reflection imaging.

For example, the display 220 in the embodiment of the present application takes a self-luminous display as an example for description. Specifically, the display screen 220 may also include a plurality of self-luminous display units, or an array of self-luminous display units. Among them, the self-luminous display unit can be used to display images. In addition, at least part of the self-luminous display unit included in the display screen 220 can also be used as a light source to emit a second light signal. The second optical signal can be used to obtain a second fingerprint image based on the reflection principle. Specifically, the second light signal can be used to illuminate a finger touching the surface of the transparent cover 210 and generate a reflected second return light signal; the light path guide structure located under the display screen 220 is used to: The signal is guided to the optical fingerprint sensor; the optical fingerprint sensor located under the display 220 is also used to: receive the second return light signal passing through the transparent cover 210, the display 220 and the light path guide structure, the second return light The signal is used to obtain the second fingerprint image of the finger. The second optical signal may be visible light. For example, the wavelength of the second optical signal may be 550 nm or other wavelengths.

Therefore, the electronic device 200 of the embodiment of the present application can generate a first fingerprint image based on the transmission imaging principle, or can generate a second fingerprint image based on the reflection imaging principle, and can also generate a second fingerprint image based on the first fingerprint image and/or the second fingerprint image. Perform fingerprint recognition.

The generation of the first fingerprint image based on the principle of transmission imaging and the generation of the second fingerprint image based on the principle of reflection imaging may be performed at the same time or at different times. However, considering that the reflected light and the transmitted light may affect each other, the two are generally not executed at the same time. That is, when acquiring the transmitted light, the reflected light can be acquired asynchronously; on the contrary, when acquiring the reflected light, the transmitted light can also be acquired asynchronously.

Specifically, the electronic device 200 may further include: a control unit for controlling the at least partially self-luminous display unit not to emit the second light signal when the light-emitting assembly emits the first light signal, and when the at least partially self-luminous When the display unit sends out the second light signal, the light-emitting component is controlled not to send out the first light signal. Specifically, the control unit may be used to control the light emitting component 230 to emit the first light signal and at least part of the self-luminous display unit to emit the second light signal, respectively. For example, the control unit may control at least part of the self-luminous display unit in the display 220 not to emit the second light signal when controlling the light-emitting assembly 230 to emit the first light signal, so that the optical fingerprint recognition device 240 only receives the first light signal. The first return light signal corresponding to the light signal is not affected by the second return light signal; on the contrary, when the control unit controls the self-luminous display unit to emit the second light signal, it controls the light emitting component 230 not to emit the first light signal. Optical signal, so that the optical fingerprint identification device 240 only receives the second return optical signal corresponding to the second optical signal, and is not affected by the first return optical signal.

In the embodiment of the present application, the optical fingerprint identification device 240 is arranged below the display 220, where the optical fingerprint identification device 240 can correspond to the optical fingerprint device 130 shown in FIGS. 1 to 4, wherein the optical fingerprint identification device The fingerprint identification device 240 may include an optical path guiding structure, which may correspond to the optical component 132 in the electronic device 10, for example, corresponding to the optical path guiding structure included in the optical component 132. For the sake of brevity, it will not be repeated here.

Specifically, the optical path guiding structure is located above the optical fingerprint sensor and is used to guide the return optical signal to the optical fingerprint sensor, where the return optical signal may refer to the first return optical signal and/or the second return optical signal.

For example, the optical path guiding structure includes an optical lens disposed above the optical fingerprint sensor for converging the return light signal passing through the display screen to the sensing array of the optical fingerprint sensor.

For another example, the light path guiding structure includes an optical collimator having a plurality of collimating units or microhole arrays, and the optical collimator is used to pass the return light signal passing through the display screen through the plurality of collimating units or microholes. The arrays are respectively transmitted to the corresponding optical sensing units in the sensing array of the optical fingerprint sensor.

For another example, the optical path guiding structure includes a microlens array with a plurality of microlenses and a light blocking layer with a plurality of microholes, and the microlens array is used to pass the return light signals passing through the display screen through the plurality of microlenses. They are respectively focused on the corresponding micro-holes of the light blocking layer, and transmitted through the micro-holes to the corresponding optical sensing units in the sensing array of the optical fingerprint sensor.

FIG. 21 shows a schematic diagram of an optical fingerprint identification device 240 according to an embodiment of the present application. Wherein, the optical fingerprint identification device 240 includes an optical fingerprint sensor 245, and may also include an optical path guiding structure. For example, FIG. 21 takes the optical path guiding structure as an optical lens 241 as an example for illustration.

Specifically, for the case where the optical path guiding structure includes the optical lens 241, since the optical lens may have aberrations for light of different wavelength bands, it is necessary to design the optical lens reasonably. Specifically, considering that the first return light signal in the embodiment of the present application may be visible light or invisible light, and the second return light signal is visible light, and the optical lens included in the optical path guiding structure can combine the first return light signal with /Or the second return light signal is guided to the optical fingerprint sensor 245. Therefore, for the case where the first return light signal is infrared light and the second return light signal is visible light, the optical lens needs to be reasonably designed so that the optical The lens can image infrared light and image visible light without aberration. That is, the aberration design of the optical lens is compatible with the wavelength light imaging in the visible light band and the infrared waveband, ensuring better imaging in the visible light and infrared waveband.

For example, the optical lens can be designed correspondingly with reference to FIG. 22. FIG. 22 shows the curve of the focus shift of the polychromatic light of the optical lens. As shown in FIG. 22, it is assumed that the first return light signal is infrared light and the wavelength is 940 nm; the second return light signal is visible light and the wavelength is 550 nm. Correspondingly, the focal position of the optical lens can be determined to avoid aberrations.

In addition, as shown in FIG. 21, a filter 242 may be provided above the optical fingerprint sensor 245. The filter 242 is used to filter out the interference of other optical signals except the first return optical signal and the second return optical signal, so as to reduce the interference of environmental stray light.

Conventional filters generally target a single wavelength, but the filters in the embodiments of the present application can be specially designed to transmit two specific wavelength bands of visible light and infrared light.

For example, FIG. 23 shows a curve of the transmittance of the filter to light of different wavelengths. As shown in Figure 23, it is assumed that the first return light signal is infrared light and the wavelength is 940nm; the second return light signal is visible light and the wavelength is 550nm. The transmittance of the filter to these two wavelengths is much greater than Light of other wavelengths, that is, the filter can be used to filter out light of wavelengths other than these two wavelengths.

Optionally, the optical fingerprint identification device 240 in the embodiment of the present application may also include other structures. For example, as shown in FIG. 21, the optical fingerprint identification device 240 may further include a flexible printed circuit (FPC) 243 and a frame 244, and the embodiment of the present application is not limited thereto. For another example, the optical fingerprint identification device 240 may further include a processor configured to generate a first fingerprint image from the first return optical signal. Among them, the processor can be set on the FPC 243.

It should be understood that the electronic device 200 adopting the embodiment of the present application can correspondingly obtain the first fingerprint image and/or the second fingerprint image. Therefore, in the fingerprint identification process, according to different application scenarios, the first fingerprint image and the / Or the second fingerprint image for identification.

Optionally, as a first embodiment, for any one touch of a finger for fingerprint recognition, the finger touching the fingerprint detection area on the surface of the transparent cover 210 can only acquire the second fingerprint image based on the second light signal . Specifically, the optical fingerprint identification device 240 in the electronic device 200 may further include a processor, through which a second fingerprint image is obtained, and the second fingerprint image is generated according to the second return light received by the optical fingerprint identification device 240 The second return light is the light signal reflected after the second light signal irradiates the finger; fingerprint identification is performed according to the second fingerprint image. That is, fingerprint images are acquired based on reflected light imaging for fingerprint recognition.

Optionally, as a second embodiment, for any one touch of a finger to perform fingerprint recognition, the finger touches the fingerprint detection area on the surface of the transparent cover 210, and the first fingerprint image based on the first light signal can also be obtained , And perform fingerprint recognition based on the first fingerprint image.

Specifically, FIG. 24 shows a schematic flowchart of a method 300 for fingerprint identification according to an embodiment of the present application. As shown in FIG. 24, the method 300 may include: S310, acquiring a first fingerprint image, the first fingerprint image being generated according to the first return light, and the first return light is the first light signal transmitted into the finger and from the The light signal transmitted by the finger; S320, perform fingerprint recognition according to the first fingerprint image.

It should be understood that the first optical signal, the first return optical signal, and the first fingerprint image in the method 300 may correspond to the first optical signal, the first return optical signal, and the first fingerprint image acquired by the electronic device 200. For simplicity, I will not repeat them here.

It should be understood that S320 may specifically include: if the first fingerprint image matches the preset fingerprint image, determining that the fingerprint recognition is successful; or, if the first fingerprint image does not match the preset fingerprint image, determining that the fingerprint recognition fails.

It should be understood that the electronic device 200 of the embodiment of the present application may further include a processor, or the optical fingerprint identification device 240 in the electronic device 200 may include the processor, and the processor is used to execute the first embodiment, that is, execute the The method 300 is not described here for brevity.

Optionally, as a third embodiment, for any one touch of a finger to perform fingerprint recognition, the finger touching the fingerprint detection area on the surface of the transparent cover 210 can also obtain both the first fingerprint image and the second fingerprint. image. Specifically, on the basis of the method 300 shown in FIG. 24, the method 300 may further include: acquiring a second fingerprint image, where the second fingerprint image is generated according to the second return light, and the second return light is the first The second light signal reflects the light signal after irradiating the finger. Correspondingly, the S320 may specifically include: if at least one of the first fingerprint image and the second fingerprint image matches a preset fingerprint image, determining that the fingerprint recognition is successful. On the contrary, if the first fingerprint image and the second fingerprint image do not match the preset image, it is determined that the fingerprint identification fails this time, for example, other identification processes can be continued after identification.

Similarly, the electronic device 200 of the embodiment of the present application may further include a processor, or the optical fingerprint identification device 240 in the electronic device 200 may include the processor, and the processor is used to execute the second embodiment, that is, to execute For the sake of brevity, the various steps in the above method 300 will not be described here.

In the embodiment of the present application, since the first fingerprint image and the second fingerprint image need to be collected, in order to avoid the influence between the first return optical signal and the second return optical signal, the two optical signals may not be detected at the same time. For example, when a finger presses the fingerprint detection area, the light-emitting component 230 may be lighted first to collect the data of the first return light signal corresponding to the transmitted light. At this time, the self-luminous display unit of the display 220 does not emit light; the first return light signal After the collection is completed, the luminous detail 230 is turned off, and the self-luminous display unit is turned on to collect the data of the second return light signal corresponding to the reflected light.

Among them, after the first return light signal collection is completed, multithreading can be started, that is, while the first fingerprint image is generated and the first fingerprint image is recognized, the second return light signal acquisition process is started, so that parallel execution can save The overall time does not affect imaging.

In addition, on the contrary, when the finger presses the fingerprint detection area, the data of the second return light signal corresponding to the reflected light can also be collected first, and then the data of the first return light signal corresponding to the transmitted light is collected. The embodiment of the present application is not limited to this.

For the acquired first fingerprint image and second fingerprint image, when any one of the fingerprint images matches the preset fingerprint image, it can be determined that the fingerprint recognition is successful, which can improve the efficiency of fingerprint recognition, especially in the case of the finger. The success rate of fingerprint recognition.

A person of ordinary skill in the art may realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed in this document can be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software depends on the specific application and design constraint conditions of the technical solution. Professionals and technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered beyond the scope of this application.

Those skilled in the art can clearly understand that, for the convenience and conciseness of description, the specific working process of the above-described system, device, and unit can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed system, device, and method may be implemented in other ways. For example, the device embodiments described above are only 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 can be combined or It can be integrated into another system, or some features can be ignored or not implemented. In addition, 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.

In addition, the functional units in each embodiment 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.

If 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. Based on this understanding, the technical solution of this application essentially or the part that contributes to the existing technology 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, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in each embodiment of the present application. 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 .

The above are only specific implementations of this application, but the protection scope of this application is not limited to this. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application. Should be covered within the scope of protection of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

An optical fingerprint identification device, suitable for electronic equipment with a display screen, characterized in that the optical fingerprint identification device includes: an optical path guide structure and an optical fingerprint sensor;

Wherein, the optical path guiding structure is configured to be arranged between the display screen and the optical fingerprint sensor to guide the first return light signal formed by a finger above the display screen to the optical fingerprint sensor;

The optical fingerprint sensor is configured to be arranged below the display screen, and includes a sensing array having a plurality of optical sensing units, and the sensing array is used to receive the first return light signal passing through the optical path guiding structure, And detecting the fingerprint image of the finger according to the first return light signal;

Wherein, the first return optical signal is the optical signal transmitted by the first optical signal into the finger, and then transmitted from the finger and passing through the display screen.
The device according to claim 1, wherein the first light signal is a light signal emitted by a light-emitting component toward the finger at a predetermined angle, wherein the light-emitting component is configured to be arranged on the edge of the display screen , And are arranged side by side with the display screen without blocking each other.
3. The device according to claim 2, wherein the light-emitting component is configured to be arranged below a non-display area on the upper surface of the electronic device, and the light-emitting component emits the first light at the predetermined angle. A light signal is irradiated to the finger touching the fingerprint detection area on the upper surface of the electronic device, and the fingerprint detection area is located in the display area on the upper surface of the electronic device.
The device according to claim 2 or 3, wherein the light-emitting component comprises a light source and a lens, and the lens is located on the upper surface of the light source;

The lens is used to converge the first light signal emitted by the light source, so that the first light signal irradiates the finger touching the fingerprint detection area.
The device according to claim 2 or 3, wherein the light-emitting component comprises a vertical cavity surface emitting laser, and the vertical cavity surface emitting laser of the laser is used to emit the first laser to the finger touching the fingerprint detection area. A light signal.
The device according to any one of claims 2 to 5, wherein the first light signal emitted by the light-emitting component is infrared light or visible light.
The device according to claim 6, wherein the wavelength of the infrared light is 940 nm; or the wavelength of the visible light is 550 nm.
The device according to any one of claims 2 to 7, wherein the light-emitting component comprises a light source, the position of the light source corresponds to the first area on the upper surface of the electronic device, and the optical fingerprint The position of the sensor corresponds to the second area on the upper surface of the electronic device,

The line connecting the center point of the first area and the center point of the second area is a first line segment, and the first line segment is perpendicular to the edge of the electronic device.
The device according to claim 8, wherein the value range of the first line segment is between 5 mm and 30 mm.
The device according to any one of claims 2 to 7, wherein the light-emitting assembly comprises a first light source and a second light source,

The position of the optical fingerprint sensor corresponds to a second area on the upper surface of the electronic device, the first light source corresponds to a third area on the upper surface of the electronic device, and the second light source corresponds to The fourth area of the surface,

The line connecting the center point of the third area and the center point of the fourth area is a second line segment, and the line connecting the center point of the second area and the midpoint of the second line segment is a third line segment, The third line segment is perpendicular to the edge of the electronic device.
The device according to claim 10, wherein the value range of the third line segment is between 5 mm and 30 mm.
11. The device according to any one of claims 2 to 11, wherein a transparent cover is arranged above the display screen, and the light-emitting component is arranged below an edge area of the transparent cover;

The transparent cover is used to provide a touch interface for the finger, and the first light signal emitted by the light-emitting component is transmitted into the finger from the transparent cover at the preset angle.
The device according to claim 12, wherein the emergence angle of the first light signal emitted by the light-emitting component on the upper surface of the transparent cover plate is less than or equal to a preset angle value.
The device according to claim 13, wherein the preset angle value ranges from 1° to 20°.
The device according to claim 13 or 14, wherein the preset value of the angle is between 10° and 20°.
The device according to any one of claims 12 to 15, wherein the distance from the incident position on the finger of the first light signal emitted by the light-emitting component to the transparent cover is less than or equal to Height preset value.
The device according to claim 16, wherein the preset height value is less than or equal to 5 mm.
The device according to any one of claims 12 to 17, wherein the transparent cover plate comprises a first light-absorbing part,

The first light-absorbing part is used to absorb the first part of the light in the first light signal emitted by the light-emitting component, so as to prevent the first part of the light from being reflected on the surface of the transparent cover plate from being transmitted to the optical Fingerprint sensor.
18. The device according to claim 18, wherein the first light absorbing part is provided in a non-display area on the upper surface of the transparent cover plate.
The device according to any one of claims 12 to 19, wherein the display screen comprises conductive glass and a polarizer close to the transparent cover plate, and the light-emitting component is located between the conductive glass and the light-emitting element. The edges of the component, the conductive glass and the polarizer are not shielded from each other.
22. The device of claim 20, wherein a second light absorbing part is provided between the light-emitting component, the conductive glass and the polarizer, and

The second light absorption part is used for absorbing the second part of the light in the first optical signal emitted by the light-emitting component, so as to prevent the second part of the light from being laterally transmitted to the conductive glass and the polarizer.
The device according to any one of claims 1 to 21, wherein the display screen comprises a plurality of self-luminous display units, and the multiple self-luminous display units are used to display images;

The optical path guiding structure is used to guide the second return optical signal formed by the finger above the display screen to the optical fingerprint sensor;

The sensing array of the optical fingerprint sensor is used to receive the second return light signal passing through the optical path guiding structure, and detect the fingerprint image of the finger according to the second return light signal;

Wherein, the second return light signal is a light signal generated by the second light signal emitted by at least part of the self-luminous display unit of the display screen irradiating the finger and generating reflection.
The device according to claim 22, wherein the optical fingerprint sensor is used to detect the first fingerprint image of the finger according to the first return light signal, and is also used to detect the first fingerprint image of the finger according to the second return light signal The second fingerprint image of the finger is detected.
The device according to claim 22 or 23, wherein the wavelength of the second optical signal is 550 nm.
The device according to any one of claims 22 to 24, wherein the device further comprises:

The control unit is configured to control the at least part of the self-luminous display unit not to emit the second light signal when the light-emitting assembly emits the first light signal, and when the at least part of the self-luminous display unit emits the first light signal When the second light signal is used, the light-emitting component is controlled not to emit the first light signal.
The device according to claim 25, wherein the device further comprises: a processor,

The processor is used for:

Acquiring a first fingerprint image, the first fingerprint image being generated according to the first return light signal;

When the first fingerprint image matches the preset fingerprint image, it is determined that the fingerprint recognition is successful; or, when the first fingerprint image does not match the preset fingerprint image, it is determined that the fingerprint recognition fails.
The device according to claim 25, wherein the device further comprises: a processor, and the processor is further configured to:

Acquiring a first fingerprint image, the first fingerprint image being generated according to the first return light signal;

Acquiring a second fingerprint image, the second fingerprint image being generated according to the second return signal light;

If at least one of the first fingerprint image and the second fingerprint image matches the preset fingerprint image, it is determined that the fingerprint recognition is successful; or, when the first fingerprint image and the second fingerprint image are both matched When the preset image does not match, it is determined that the fingerprint recognition fails.
The device according to any one of claims 22 to 27, wherein the optical path guiding structure comprises an optical lens, and the optical lens is arranged above the optical fingerprint sensor for passing through the display screen. The return light signal of the optical fingerprint sensor is converged to the sensing array of the optical fingerprint sensor.
The device of claim 28, wherein the first return light signal is infrared light, and the second return light signal is visible light,

The optical lens can image infrared light and has no aberration for visible light imaging.
The device according to claims 22 to 27, wherein the light path guiding structure comprises an optical collimator having a plurality of collimating units or a microhole array, and the optical collimator is used to pass through the display The return light signal of the screen is respectively transmitted to the corresponding optical sensing unit in the sensing array of the optical fingerprint sensor through the multiple collimating units or microhole array; or,

The optical path guiding structure includes a microlens array with a plurality of microlenses and a light blocking layer with a plurality of microholes, and the microlens array is used to pass the return light signal passing through the display screen through the plurality of microlenses. The lenses are respectively focused on the microholes corresponding to the light blocking layer, and are transmitted through the microholes to the corresponding optical sensing units in the sensing array of the optical fingerprint sensor.
The device according to any one of claims 22 to 30, wherein the device further comprises:

The optical filter is located above the optical fingerprint sensor, and the optical filter is used to filter other optical signals other than the first return optical signal and the second return optical signal.
The device according to claim 31, wherein the first return optical signal is infrared light with a wavelength of 940 nm, and the second return optical signal is visible light with a wavelength of 550 nm,

The filter is used to filter at least light whose wavelength is not equal to 940nm and 550nm.
An electronic device, characterized by comprising: the optical fingerprint identification device according to any one of claims 1 to 32.
A fingerprint identification method, suitable for the optical fingerprint identification device according to any one of claims 1 to 32, characterized in that the fingerprint identification method comprises:

Acquiring a first fingerprint image, where the first fingerprint image is generated according to a first return light, and the first return light is a light signal transmitted into and out of the finger by the first light signal;

According to the first fingerprint image, fingerprint recognition is performed.
The method according to claim 34, wherein the performing fingerprint recognition according to the first fingerprint image comprises:

If the first fingerprint image matches the preset fingerprint image, it is determined that the fingerprint recognition is successful; or,

If the first fingerprint image does not match the preset fingerprint image, it is determined that the fingerprint recognition fails.
The method according to claim 34, wherein the method further comprises:

Acquiring a second fingerprint image, where the second fingerprint image is generated according to a second return light, and the second return light is a light signal reflected after the second light signal irradiates the finger;

The performing fingerprint recognition according to the first fingerprint image includes:

If at least one of the first fingerprint image and the second fingerprint image matches a preset fingerprint image, it is determined that the fingerprint recognition is successful.
The method according to claim 36, wherein the performing fingerprint recognition according to the first fingerprint image comprises:

If both the first fingerprint image and the second fingerprint image do not match the preset image, it is determined that the fingerprint recognition fails.