CN113469140A - Optical fingerprint identification module under translation formula screen - Google Patents

Abstract

The invention belongs to the technical field of micro sensors, and discloses a translation type under-screen optical fingerprint identification module which is arranged in terminal equipment with a screen and used for acquiring fingerprint information attached to the corresponding position of the screen, wherein the translation type under-screen optical fingerprint identification module comprises a sensor and a lens module; the optical fiber sensor also comprises an actuating module connected with the sensor, and the actuating module pushes the sensor to move in the plane direction perpendicular to the incident light to enlarge the field of view.

Description

Optical fingerprint identification module under translation formula screen

Technical Field

The invention belongs to the technical field of micro sensors, and particularly relates to a translation type under-screen optical fingerprint identification module.

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, because the area for identification on the screen is small, a fingertip is required to be continuously moved when a fingerprint is input, so that the equipment can acquire more complete fingerprint information, meanwhile, because the acquired information is less during identification, light touch cannot pass through generally, the contact area is small, and therefore 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 slow.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a translation type optical fingerprint identification module under a screen, which can move a sensor on a horizontal plane by utilizing a sensor horizontal moving technology, and effectively increase the area for taking a fingerprint image under the condition of using the same sensor.

The technical scheme adopted by the invention is as follows:

in a first aspect, the invention provides a translational under-screen optical fingerprint identification module, which is arranged in a terminal device with a screen, is used for acquiring finger fingerprint information attached to a corresponding position of the screen, and comprises a sensor and a lens module; the optical fiber sensor also comprises an actuating module connected with the sensor, and the actuating module pushes the sensor to move in the plane direction perpendicular to the incident light to enlarge the field of view.

The principle of optical fingerprint identification under the screen is that one side of a finger fingerprint attached to the screen is irradiated by a light source, so that fingerprint reflected light generated by the finger fingerprint 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. Since the devices provided with such identification modules are generally compact-class mobile terminals with displays (mainly touch displays), there is a demand for improving screen occupation, and various functional modules are provided 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 panel and the protective glass covering the surface of the display panel.

The above has shown that the technology of fingerprint identification under the screen needs special treatment to the screen, so that the light transmittance of the detection area can meet the identification requirement of the built-in sensor. Since the special treatment affects the normal display of the screen, the prior art mostly only sets a circular area on the lower side of the screen, and the finger print surface in the circular area is identified by irradiation. The plane displacement technology of the invention can expand the visual field range as much as possible on the premise of not changing the size of the original sensor, thereby obtaining more fingerprint images in a limited space.

The view range refers to the maximum range of information that can be acquired by the corresponding sensor, and the acquired image is not necessarily a complete single finger fingerprint, so that the amount of acquired information needs to be increased, and the view range needs to be expanded. The simplest method is to use a larger sensor to increase the size, but this method is not suitable for a terminal device with insufficient internal installation space. The size of the sensor is not changed, the lens module is not adjusted, and the sensor is pushed to move within a certain range only by the arranged actuating module, so that a wider sampling range can be obtained compared with a fixed mounting mode.

It is worth mentioning that the actuation module is connected to the sensor and pushes it into motion from at least two directions, thus creating a smooth movement in a single plane.

In combination with the first aspect, the present invention provides a first implementation manner of the first aspect, wherein the actuation module includes at least two sets of mutually perpendicular lead screws with independent motors, and the lead screws push the sensors to move in a plane.

It is worth to be noted that, if planar movement is to be achieved through the lead screws and the motors, one of the lead screws is the main lead screw, and the other lead screw is the auxiliary lead screw. The main lead screw and the corresponding motor push the auxiliary lead screw and the sensor together. And the auxiliary lead screw is connected with the main lead screw and the sensor, and can push the sensor relative to the main lead screw. The structure has good stability and stopping effect, and can realize plane movement quickly and stably. Meanwhile, a proper control program is set, so that the finger can quickly sweep a certain area when being attached, and a plurality of pictures are shot by the sensor for identification, so that the success rate is improved.

In combination with the first aspect, the present disclosure provides a second implementation manner of the first aspect, wherein the actuation module is a voice coil motor including a magnet and a coil.

Different from a lead screw structure, the voice coil motor has the characteristics of small volume and simple structure, is low in delay and can be started quickly. The stopping performance of the screw rod structure is not better than that of the screw rod structure only due to the fact that the elastic sheet provides limiting and resetting effects. 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.

In combination with the first or second embodiment of the first aspect, the present invention provides a third embodiment of the first aspect, wherein the sensor is independent from the lens module, and the lens module is fixed in the screen or pushed by another separately arranged actuating module to keep relatively still with the sensor.

With reference to the first or second implementation manner of the first aspect, the present invention provides a fourth implementation manner of the first aspect, wherein the sensor is fixedly connected to the lens module. Different from the above-mentioned and embodiment, the lens module and the sensor are pushed to synchronously move by the actuating module, so that the wide-range movement can be realized to obtain a larger identification range. The range of the sampling range can be expanded by only moving the sensor, but the range is limited, and the effective range of the lens module cannot be exceeded. If large-area identification sampling is to be realized, a wide-angle lens module is required to be adopted, the moving range is required to be enlarged, and an image meeting the identification requirement can be acquired after the wide-angle lens module moves for a certain distance.

With reference to the first or second implementation manner of the first aspect, the present invention provides a fifth implementation manner of the first aspect, where 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, and the fingerprint reflected light is formed by screen luminous irradiation.

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 panel 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 and the first or second embodiment of the first aspect, the present invention provides a seventh embodiment of the first aspect, wherein the fingerprint reflected light is formed by reflecting an infrared emission source disposed inside the screen toward the surface of the finger. 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 the screen imaging and panel specific area is not influenced, and the identification efficiency is improved.

With reference to the fifth implementation manner of the first aspect, the invention provides an eighth implementation manner of the first aspect, wherein an optical filter is disposed between the sensor and the lens module.

The invention has the beneficial effects that:

the invention uses the sensor horizontal moving technology to move the chip in the X/Y direction of a plane, and effectively increases the area of fingerprint image taking under the condition of using the same chip, so that the development cost of the lens is lower than that of the chip.

Drawings

FIG. 1 is an external view of an optical fingerprint recognition module of the present invention applied to a mobile phone;

FIG. 2 is a schematic diagram illustrating the principle of the present invention that a single finger is displaced without moving the finger to obtain a complete image as much as possible;

FIG. 3 is a schematic side view of the optical fingerprint recognition module according to the present invention;

FIG. 4 is an isometric view of the specific structure of the whole optical fingerprint identification module of the present invention inembodiment 1;

FIG. 5 is an isometric view of the internal structure of the optical fingerprint recognition module of the present invention after the housing is removed inembodiment 1;

fig. 6 is a schematic diagram illustrating the recognition of the entire optical fingerprint recognition module in the screen light-emitting reflective state according to the present invention.

In the figure: 1-sensor, 1 a-initial position, 1B-mobile position, 2-optical filter, 3-lens module, 4-base, 5-shell, A-initial view and B-mobile view.

Detailed Description

The invention is further explained below with reference to the drawings and the specific 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:

the conventional smart phones with high screen occupation ratio mainly comprise a plurality of necessary biometric identification modules, which can only be adjusted and optimized, and a plurality of manufacturers advance the technology of fingerprint identification under the screen, but the identification efficiency and the success rate of the technology of fingerprint identification under the screen are lower than those of the conventional entity identification key, so that in order to improve the identification rate, the sampling range is improved by the technology of theplanar motion sensor 1, so that more fingerprint information is obtained, and the identification rate is improved.

The present embodiment discloses an optical fingerprint recognition module under a screen with a planar movingsensor 1, as shown in fig. 3-6, 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 is also shown at the same time.

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

A plurality of magnets are arranged on thebase 4, a coil is arranged on the back surface or the outer annular surface of the fixing plate of thesensor 1, and ahall 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 thebase 4, the coil will be pushed by the acting force and drive thewhole 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).

Thelens module 3 is fixed in the housing 5, the end surface of the light-entering side faces the screen direction, and the axial direction of the lens module is vertical to the screen. And the axis of thelens module 3 passes through the center of the fingerprint identification area on the screen. 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 formed locally on the screen 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 is irradiated to the surface of the finger from the self-illumination, and when the light reflected from the end face of the finger fingerprint enters the screen, the light can be adjusted by thelens module 3 and then emitted to thesensor 1.

In fig. 6, it can be seen that the light beam is focused on the surface of thesensor 1 after being converged by thelens module 3. The surface of thesensor 1 is also covered with theoptical filter 2, and theoptical filter 2 can filter other non-object rays and retain the fingerprint reflected light to enter thesensor 1, so that the identification precision is improved.

While in fig. 2 it can be seen that the area occupied by a complete finger fingerprint is significantly larger than the identification area shown in a black box, the prior art achieves a large sampling range by continuously moving the finger. In this embodiment, the displacement in at least four directions is performed in the manner shown in fig. 2 by driving the movingsensor 1 or the entire movingsensor 1 and the camera module through the coil without changing the original screen recognition area. The dotted line frame in fig. 2 represents a moving view B, and the solid line frame is an initial view a, and the moving view B in the up, down, left, and right directions can cover the whole finger fingerprint surface with high probability, and can be realized only through four moving steps, thereby improving the recognition efficiency.

Fig. 6 shows the actual movement, where the dashed line is themovement position 1b of thesensor 1 and the solid line is the initial position 1 a.

Example 2:

the present embodiment also discloses an off-screen optical fingerprint identification module forsensor 1 displacement, which is different fromembodiment 1 in that a terminal device in the present embodiment is provided with a separate light source, i.e., an infrared emission source. By being disposed near the recognition area, infrared light is projected toward the recognition area of the screen. 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-described alternative embodiments, and various other forms of products can be obtained by anyone in light of the present invention. The above detailed description should not be taken as limiting the scope of the invention, which is defined in the claims, and which the description is intended to be interpreted accordingly.

Claims (9)

Translated fromChinese

1.一种平移式屏下光学指纹识别模块，设置在具有屏幕的终端设备内，用于获取贴合在屏幕对应位置的手指指纹信息，包括传感器(1)和镜头模组(3)；其特征在于：还包括与传感器(1)连接的致动模组，通过致动模组推动传感器(1)在沿垂直于入射光线的平面方向移动扩大视界范围。1. A translational under-screen optical fingerprint identification module, arranged in a terminal device with a screen, for obtaining finger fingerprint information attached to a corresponding position of the screen, comprising a sensor (1) and a lens module (3); It is characterized in that: it also includes an actuating module connected with the sensor (1), and the sensor (1) is pushed to move along a plane direction perpendicular to the incident light by the actuating module to expand the field of view.2.根据权利要求1所述的一种平移式屏下光学指纹识别模块，其特征在于：所述致动模组包括至少两组相互垂直且带有独立电机的丝杠，由丝杠推动传感器(1)在平面内移动。2 . The optical fingerprint identification module under a translational screen according to claim 1 , wherein the actuating module comprises at least two sets of mutually perpendicular lead screws with independent motors, and the lead screws push the sensor. 3 . (1) Move in the plane.3.根据权利要求1所述的一种平移式屏下光学指纹识别模块，其特征在于：所述致动模组为包括磁体和线圈的音圈马达。3 . The translational under-screen optical fingerprint identification module according to claim 1 , wherein the actuating module is a voice coil motor comprising a magnet and a coil. 4 .4.根据权利要求2或3所述的一种平移式屏下光学指纹识别模块，其特征在于：所述传感器(1)与镜头模组(3)相互独立，所述镜头模组(3)固定在屏幕内或通过单独设置的另一致动模组推动与传感器(1)保持相对静止。4. A translational under-screen optical fingerprint identification module according to claim 2 or 3, characterized in that: the sensor (1) and the lens module (3) are independent of each other, and the lens module (3) The sensor (1) is fixed in the screen or pushed and kept relatively stationary by another actuating module set separately.5.根据权利要求2或3所述的一种平移式屏下光学指纹识别模块，其特征在于：所述传感器(1)与镜头模组(3)固定连接。5. A translational under-screen optical fingerprint identification module according to claim 2 or 3, wherein the sensor (1) is fixedly connected to the lens module (3).6.根据权利要求2或3所述的一种平移式屏下光学指纹识别模块，其特征在于：所述致动模组包括设置在终端设备内的外壳(5)，镜头模组(3)和传感器(1)设置在外壳(5)内；传感器(1)下部设有通过弹片连接的底座，传感器(1)上具有线圈，底座上设有磁体。6. The optical fingerprint identification module under a translational screen according to claim 2 or 3, wherein the actuating module comprises a housing (5) arranged in the terminal device, a lens module (3) The sensor (1) and the sensor (1) are arranged in the casing (5); the lower part of the sensor (1) is provided with a base connected by elastic sheets, the sensor (1) is provided with a coil, and the base is provided with a magnet.7.根据权利要求1-3任一项所述的一种平移式屏下光学指纹识别模块，其特征在于：所述指纹反射光由屏幕发光照射形成。7. A translational under-screen optical fingerprint identification module according to any one of claims 1-3, wherein the fingerprint reflected light is formed by illuminating the screen.8.根据权利要求1-3任一项所述的一种平移式屏下光学指纹识别模块，其特征在于：所述指纹反射光由设置在屏幕内侧的红外发射源射向手指表面反射形成。8. A translational under-screen optical fingerprint identification module according to any one of claims 1-3, wherein the fingerprint reflected light is formed by the infrared emitting source disposed on the inner side of the screen radiating toward the surface of the finger.9.根据权利要求6所述的一种平移式屏下光学指纹识别模块，其特征在于：所述传感器(1)与镜头模组(3)之间设有滤光片(2)。9. A translational under-screen optical fingerprint identification module according to claim 6, wherein a filter (2) is arranged between the sensor (1) and the lens module (3).

Images