CN215264842U - Optical fingerprint identification module under screen of axial displacement - Google Patents

Abstract

The utility model belongs to the technical field of microsensors, and discloses an axially-moving optical fingerprint identification module under a screen, which is arranged in terminal equipment with a screen and used for acquiring finger fingerprint information attached to a corresponding position of the screen, and comprises a lens module and a sensor which can move relatively, wherein the lens module guides fingerprint reflected light outside the screen to the sensor for imaging; the fingerprint surface adjusting device further comprises an actuating module which is at least connected with any one of the lens module and the sensor, and the actuating module pushes one or more of the lens module and the sensor to move along the incident direction of light rays so as to compensate the distance difference between the fingerprint surface and the screen.

Description

Optical fingerprint identification module under screen of axial displacement

Technical Field

The utility model belongs to the technical field of microsensor, concretely relates to optical fingerprint identification module under screen of axial displacement.

Background

The fingerprint identification technology is one of the most widely used biometric identification technologies, namely, the biometric identification technology, which is used for identifying the identity of a person by using the inherent physiological characteristics or behavior characteristics of the human body, has wide application prospects in the fields of identity authentication identification and network security due to the advantages of convenience, safety and the like of biometric identification, and the available biometric identification technologies include fingerprints, human faces, voiceprints, irises and the like, wherein the fingerprints are the most widely applied technologies. At present, fingerprint identification technologies can be classified into three categories: capacitive fingerprint identification, optical screen fingerprint identification and ultrasonic fingerprint identification.

Because mobile terminal equipment such as current cell-phones all can adopt biological identification technique as a safety guarantee measure, nevertheless along with the continuous development of technique, people also improve gradually to the demand of full face screen, can enlarge display area as far as possible on effectual terminal equipment, will certainly crowd the space that occupies other functional modules. The existing fingerprint identification technology needs to be arranged outside a shell and directly contacts with the surface of a finger, and in order to further improve the external integrity of terminal equipment such as a mobile phone, various manufacturers research and develop the fingerprint identification technology under a screen to replace an entity identification key. The optical screen fingerprinting and the ultrasonic fingerprinting mentioned in the above are feasible solutions.

The ultrasonic fingerprint identification technology has higher cost and complex structure, and the optical fingerprint identification equipment and the solution are mature and have lower cost. However, since optical fingerprint recognition has certain requirements on the light transmittance of the screen, special processing is inevitably performed on the screen at the recognition area when the requirements are met, and the normal display effect of the screen is influenced by the special processing. Therefore, in order to ensure the appearance of the whole screen, the screen identification area is not too large, the existing identification equipment generally adopts a fixed structure, the structure cannot acquire more light reflection information in a limited screen identification area, and different from ultrasonic waves, optical identification is carried out by comparison and identification according to acquired image information, once a protective film is attached to the surface of the structure or finger pressing force causes screen deformation, a fingerprint image acquired under the original determined focal length condition becomes fuzzy, so that the identification rate is influenced, and the fixed structure is one of the reasons that the identification rate of a fingerprint identification module under the existing optical screen is slower.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem that prior art exists, the utility model provides an optical fingerprint identification module under axial displacement's the screen, but the image that the compensation optimization caused on the screen is pasted the laminating at the protection that uses different thickness is fuzzy.

The utility model discloses the technical scheme who adopts does:

in a first aspect, the present invention provides an axially moving underscreen optical fingerprint recognition module, disposed in a terminal device having a screen, for acquiring finger fingerprint information attached to a corresponding position of the screen, including a relatively movable lens module and a sensor, wherein the lens module guides fingerprint reflected light outside the screen to the sensor for imaging;

the fingerprint surface adjusting device further comprises an actuating module which is at least connected with any one of the lens module and the sensor, and the actuating module pushes one or more of the lens module and the sensor to move along the incident direction of light rays so as to compensate the distance difference between the fingerprint surface and the screen.

The principle of optical fingerprint identification under the screen is that a light source irradiates one side of a finger fingerprint attached to the screen, so that fingerprint reflected light generated by the light source can be fed back to a sensor, the fingerprint reflected light is converted into an electric signal after being identified by the sensor and is sent to the outside, and an external processor processes, analyzes and compares acquired fingerprint image data.

The devices provided with such identification modules are generally compact mobile terminals with a display (mainly a touch display), and there is a demand for improving the screen occupation ratio by arranging various functional modules as built-in as possible. Since the built-in sensor needs to receive external reflected light, the structure of the common LCD screen with the backlight plate cannot meet the requirement, and the screen is generally an OLED screen, and the screen in the above description is the display screen and the protective glass covering the surface of the display screen.

Although the thickness of the screen and the thickness of the protective glass are set conditions, the distance between the lens module and the sensor can be calculated and determined according to the thicknesses of the two layers of light-transmitting structures during debugging. However, due to the influence of the finger-contacting state or other obstacles such as a protective film on the outer surface of the screen, the best fingerprint influence cannot be obtained by the fixed identification module. The event the utility model discloses in adjust the focus through the identification module that can axial displacement, actuating module wherein can remove one or two in sensor and the camera lens module to whether focus according to the image information analysis that acquires through outside processing module, the accessible laser rangefinder is focused or the inside phase place mode of focusing acquires the distance data that need remove, thereby actuates the module action by processing module control and promotes the completion work of focusing.

It is worth also saying that the distance between the finger-print surface and the screen is small due to the protective film or other factors, and for a common camera module, the above error influence is small and can be ignored. However, due to the optical fingerprint identification under the screen, the original light transmission amount is smaller than a normal value, the focal length of the optical fingerprint identification is small, and the optical fingerprint identification belongs to a microspur state, and the identification efficiency is influenced by the change identification of one point and one space. And the utility model provides an actuating module volume is less, and it removes the stroke equally less, can fully satisfy the demand of focusing of discernment module in certain little removal stroke.

In combination with the first aspect, the present invention provides a first implementation manner of the first aspect, wherein the actuating module is connected to the lens module and controls the operation through an external circuit.

The actuating module directly realizes focusing by adjusting the movement of the lens module, and the sensor is fixed on the inner side of the screen of the terminal equipment and is the same as the existing miniature camera.

In combination with the first aspect, the present invention provides a second implementation manner of the first aspect, wherein the actuating module is connected to the sensor and controls the operation through an external circuit.

Because the sensor has smaller thickness and weight, the driving force required by the actuating module is smaller than that for driving the lens module, so that the volume of the actuating module can be further reduced.

With reference to the first or second implementation manners of the first aspect, the present invention provides a third implementation manner of the first aspect, wherein the actuating module is a voice coil motor including a magnet and a coil.

The so-called voice coil motor is an electromagnetic actuating structure commonly used in a miniature camera, and mainly comprises a magnet and a coil, wherein an electrified coil can form an interaction force with the magnet in an effective magnetic field range of the magnet, and then the movement control is realized by fixing one end to move the other end or elastically connecting the two ends to have a fixed state and by means of relative movement of the two parts. Because the voice coil motor is small in size and controllable in motion, the voice coil motor can meet the moving requirement of a small stroke.

With reference to the first or second embodiment of the first aspect, the present invention provides a fourth embodiment of the first aspect, wherein the actuating module is a micro-motor assembly.

The so-called micro-motor assembly is also an electric mechanism commonly used in mobile terminal equipment, and is generally in a screw motor structure, and the existing mobile phone lifting camera adopts the action mechanism. Its volume is less to can the accurate control move the stroke, also be applicable to equally the utility model discloses a demand.

With reference to the third implementation manner of the first aspect, the present invention provides a fifth implementation manner of the first aspect, wherein the actuation module includes a housing disposed in the terminal device, and the lens module and the sensor are disposed in the housing; the lower part of the sensor is provided with a base connected through a spring plate, the sensor is provided with a coil, and the base is provided with a magnet.

With reference to the first aspect, the first or second implementation manner of the first aspect, the present invention provides a sixth implementation manner of the first aspect, wherein the fingerprint reflected light is formed by screen illumination.

It should be noted that, the screen itself is a light source, and the existing under-screen optical fingerprint recognition modules all set a recognition area at a corresponding position, and process the screen in the area, so as to improve the light transmittance without reducing the image quality as much as possible. Then, the specific area emits light to prompt a finger to press, and the intensity of the reflected light can meet the identification requirement due to the small distance. And the filter additionally arranged can filter other external light, and only special fingerprint emission light is reserved.

With reference to the first aspect or the first or second embodiment of the first aspect, the present invention provides a seventh embodiment of the first aspect, wherein the fingerprint reflection light is formed by reflecting an infrared emission source disposed inside the screen toward a finger surface.

Different from the screen excitation mode, the independently arranged infrared emission source can emit invisible light, interference can be reduced through a special light source on the basis that the service life of the light emitting unit in a screen imaging area and a screen specific area is not influenced, and the identification efficiency is improved.

In combination with the fifth implementation manner of the first aspect, the present invention provides an eighth implementation manner of the first aspect, wherein an optical filter is disposed between the sensor and the lens module.

The utility model has the advantages that:

the utility model compensates and optimizes the image blurring caused by the use of the protective stickers with different thicknesses by consumers, and can adjust the back focus according to different wavelengths to obtain the clearest image; visible light emitted by the screen is used for fingerprint identification on the surface of the skin, and infrared light is used for biological living body identification on blood vessels and blood flow in the skin;

meanwhile, the three-dimensional information of the fingerprint can be obtained by axial scanning, and the size variation of the mobile phone (including the fingerprint module) caused by temperature variation can be compensated and optimized; just the utility model provides a camera lens need not remove.

Drawings

Fig. 1 is an external diagram of the application of the whole optical fingerprint recognition module of the present invention on a mobile phone;

FIG. 2 is a schematic side view of the optical fingerprint recognition module according to the present invention;

fig. 3 is a schematic side view of the whole optical fingerprint recognition module of the present invention in embodiment 1;

fig. 4 is an isometric view of the internal structure of the whole optical fingerprint identification module of the present invention after the housing is removed in embodiment 1;

FIG. 5 is a schematic diagram of the whole optical fingerprint recognition module according to the present invention in the state of screen light-emitting reflection;

fig. 6 is a schematic diagram of the recognition of the present invention when a protective film is covered on the screen on the basis of fig. 5;

fig. 7 is the utility model discloses whole optics fingerprint identification module is setting up infrared light source's discernment schematic diagram alone.

In the figure: 1-sensor, 2-optical filter, 3-lens module, 4-base, 5-shell, 6-infrared emission source, 7-screen and 8-protective film.

Detailed Description

The present invention will be further explained with reference to the drawings and the embodiments.

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present application, it should be noted that if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are used for indicating the orientation or positional relationship based on the orientation or positional relationship shown in the drawings or the orientation or positional relationship which is usually placed when the product of the application is used, the description is only for convenience and simplicity, and the indication or suggestion that the referred device or element must have a specific orientation, be constructed in a specific orientation and be operated, and thus, should not be construed as limiting the present application. Furthermore, the appearances of the terms "first," "second," and the like in the description herein are only used for distinguishing between similar elements and are not intended to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical" and the like when used in the description of the present application do not require that the components be absolutely horizontal or overhanging, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present application, it should also be noted that, unless otherwise explicitly stated or limited, the terms "disposed," "mounted," "connected," and "connected" should be interpreted broadly, e.g., as being fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

Example 1:

many existing smart phones mainly have a high screen occupation ratio, and better visual experience can be brought by improving the screen occupation ratio. However, since the originally necessary biometric identification module can only be adjusted and optimized, many manufacturers advance the technology of underscreen fingerprint identification, but the identification efficiency of underscreen fingerprint identification equipment on the market is lower than that of the entity identification module, and the identification success rate is obviously reduced after the protective film 8 is attached, and then all manufacturers search for improving the identification success rate.

The present embodiment discloses an optical fingerprint recognition module under a screen capable of moving axially, as shown in fig. 2 to 6, the specific structure of the module in the present embodiment is shown in the drawings, including a complete state and a split state, and the schematic diagram of the optical path of the module for fingerprint recognition under the screen 7 is also shown.

Specifically, the module is an independent structure arranged in the mobile terminal equipment, the lighting end of the module comprises a shell 5 and a base 4 which are mutually buckled, a lens module 3 and a sensor 1 which are mutually independent are arranged in the shell 5, a plurality of fixed lenses are arranged in the lens module 3, and the sensor 1 is of a similar rectangular plate structure and is movably connected with the shell 5 or the base 4 through an elastic connecting piece.

A plurality of magnets are arranged on the base 4, a coil is arranged on the back surface or the outer annular surface of the fixing plate of the sensor 1, and a hall sensor 1 is arranged at the inner center part of the coil and used for detecting the movement distance to form a control closed loop.

The coil is connected with an external control circuit through an FPC, and the coil and the magnet generate interaction force by inputting current by the control circuit. Since the magnet is fixed on the base 4, the coil will be pushed by the acting force and drive the whole sensor 1 to perform directional movement. (the principle of the controllable relative motion between the magnet and the coil is common knowledge in the field, and the present embodiment does not require any driving force or control logic, and therefore is not described in detail).

The lens module 3 is fixed in the housing 5, and the end surface of the light-entering side faces the direction of the screen 7, and the axial direction of the lens module is vertical to the screen 7. And the axis of the lens module 3 passes through the center of the fingerprint identification area on the screen 7. As can be seen in fig. 1, the mobile terminal device is a full-screen smart phone, and the lower side of the front of the smart phone has an identification area, and a circular bright spot is locally formed on the screen 7 to indicate that the user places a finger thereon.

When the finger is already attached to the corresponding area as shown in fig. 5, the circular bright spot still keeps the lighted state, and the brightness can be improved when the finger is attached to the corresponding area to increase the recognition efficiency. At this time, the screen 7 emits light to the surface of the finger, and when the light reflected from the end face of the finger enters the screen 7, the light can be adjusted by the lens module 3 and then emitted to the sensor 1.

In fig. 5, it can be seen that the light beam is focused on the surface of the sensor 1 after being converged by the lens module 3. The surface of the sensor 1 is also covered with the optical filter 2, and the optical filter 2 can filter other non-object rays and retain the fingerprint reflected light to enter the sensor 1, so that the identification precision is improved.

In fig. 6, it can be seen that the screen 7 is covered with a protective film 8, and the finger surface originally in focus is moved upward due to the presence of the protective film 8. Since the gaps from the screen 7 to the lens module 3 and from the lens module 3 to the sensor 1 are small, once the surface of the finger as the sampling object is displaced, the focus is liable to be out of the effective range recognized by the sensor 1. Therefore, the sensor 1 is axially moved by the coil under the control of the external mobile phone processor in the embodiment. In fig. 6, in order to adapt to the existence of the protective film 8, the sensor 1 is moved upward, so that the changed focus can fall on the sensor 1, and a clearer image can be obtained, thereby improving the recognition efficiency.

Example 2:

the present embodiment also discloses an off-screen optical fingerprint recognition module, which is different from embodiment 1 in that, as shown in fig. 7, a single light source, i.e. an infrared emission source 6, is provided inside the terminal device in this embodiment. By being disposed near the recognition area, infrared light is projected toward the recognition area of the screen 7. The infrared light can not only perform fingerprint identification through finger reflection, but also perform organism identification, and the mobile phone can acquire the pulse and even the blood oxygen saturation information of the user through the extraction and analysis of the reflected light information of the blood vessel.

The present invention is not limited to the above-mentioned alternative embodiments, and various other products can be obtained by anyone under the teaching of the present invention. The above detailed description should not be taken as limiting the scope of the invention, which is defined in the following claims, and which can be used to interpret the claims.

Claims (9)

1. An optical fingerprint identification module under an axially moving screen is arranged in terminal equipment with a screen and used for acquiring finger fingerprint information attached to the corresponding position of the screen, and comprises a lens module (3) and a sensor (1) which can move relatively, wherein fingerprint reflected light outside the screen is guided to the sensor (1) by the lens module (3) for imaging;

the method is characterized in that: the fingerprint surface adjusting device further comprises an actuating module which is at least connected with any one of the lens module (3) and the sensor (1), and the actuating module pushes one or more of the lens module and the sensor to move along the incident direction of light rays so as to compensate the distance difference between the fingerprint surface and the screen.

2. The axially moving underscreen optical fingerprint recognition module of claim 1, wherein: the actuating module is connected with the lens module (3) and controls the action through an external circuit.

3. The axially moving underscreen optical fingerprint recognition module of claim 1, wherein: the actuating module is connected with the sensor (1) and controls the action through an external circuit.

4. An axially moving underscreen optical fingerprint recognition module as claimed in claim 2 or 3, wherein: the actuation module is a voice coil motor including a magnet and a coil.

5. An axially moving underscreen optical fingerprint recognition module as claimed in claim 2 or 3, wherein: the actuating module is a micro-motor assembly.

6. The axially moving underscreen optical fingerprint recognition module of claim 4, wherein: the actuating module comprises a shell (5) arranged in the terminal equipment, and the lens module (3) and the sensor (1) are arranged in the shell (5); the lower part of the sensor (1) is provided with a base connected through an elastic sheet, the sensor (1) is provided with a coil, and the base is provided with a magnet.

7. The axially moving underscreen optical fingerprint recognition module of any one of claims 1-3, wherein: the fingerprint reflection light is formed by screen luminous irradiation.

8. The axially moving underscreen optical fingerprint recognition module of any one of claims 1-3, wherein: the fingerprint reflection light is formed by reflecting an infrared emission source (6) arranged on the inner side of the screen to the surface of a finger.

9. The axially moving underscreen optical fingerprint recognition module of claim 6, wherein: and an optical filter (2) is arranged between the sensor (1) and the lens module (3).

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