CN112507960A - Fingerprint sensing module and fingerprint sensing method - Google Patents
Fingerprint sensing module and fingerprint sensing method Download PDFInfo
- Publication number
- CN112507960A CN112507960A CN202011524267.2A CN202011524267A CN112507960A CN 112507960 A CN112507960 A CN 112507960A CN 202011524267 A CN202011524267 A CN 202011524267A CN 112507960 A CN112507960 A CN 112507960A
- Authority
- CN
- China
- Prior art keywords
- image
- fingerprint
- fingerprint sensing
- light source
- generate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 33
- 238000012545 processing Methods 0.000 claims abstract description 49
- 230000003287 optical effect Effects 0.000 claims description 6
- 230000000873 masking effect Effects 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 12
- 239000011159 matrix material Substances 0.000 description 8
- 238000005286 illumination Methods 0.000 description 3
- 238000010191 image analysis Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 1
- 238000003708 edge detection Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
- G06V40/10—Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
- G06V40/12—Fingerprints or palmprints
- G06V40/13—Sensors therefor
- G06V40/1324—Sensors therefor by using geometrical optics, e.g. using prisms
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Human Computer Interaction (AREA)
- General Physics & Mathematics (AREA)
- Multimedia (AREA)
- Theoretical Computer Science (AREA)
- Image Input (AREA)
- Collating Specific Patterns (AREA)
- Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)
Abstract
本发明提供一种指纹感测模块以及指纹感测方法。指纹感测模块包括光源、指纹感测器以及处理模块。指纹感测器感测经光源照明的手指以及未经光源照明的手指，以取得第一图像以及第二图像。处理模块耦接指纹感测器。处理模块依据第一图像以及第二图像判断指纹图像区域，以产生指纹图像。
The present invention provides a fingerprint sensing module and a fingerprint sensing method. The fingerprint sensing module includes a light source, a fingerprint sensor and a processing module. The fingerprint sensor senses a finger illuminated by the light source and a finger not illuminated by the light source to obtain a first image and a second image. The processing module is coupled to the fingerprint sensor. The processing module determines a fingerprint image area according to the first image and the second image to generate a fingerprint image.
Description
Technical Field
The present invention relates to a sensing device, and more particularly, to a fingerprint sensing module and a fingerprint sensing method.
Background
For the current optical fingerprint sensing technology, since the fingerprint sensor may capture a fingerprint image (image of a finger-pressed area) and a non-fingerprint image (image of a non-finger-pressed area) simultaneously during the process of acquiring the fingerprint image, the back-end processor often needs to design a special and complex image recognition algorithm to distinguish the images. It is common that when the appearance of the non-fingerprint image portion after the sensing image is processed is similar to that of a finger fingerprint, the back-end processor will make a False positive, which affects the False Rejection Rate (FRR) or False Acceptance Rate (FAR) of the recognition system. In view of this, several embodiments of solutions will be presented below.
Disclosure of Invention
The invention is directed to a fingerprint sensing module and a fingerprint sensing method, which can provide a fingerprint image with high identifiability.
According to an embodiment of the present invention, a fingerprint sensing module of the present invention includes a light source, a fingerprint sensor, and a processing module. The fingerprint sensor senses the finger illuminated by the light source and the finger not illuminated by the light source to acquire a first image and a second image. The processing module is coupled with the fingerprint sensor. The processing module judges the fingerprint image area according to the first image and the second image so as to generate a fingerprint image.
According to an embodiment of the invention, the fingerprint sensing method of the invention is adapted to a fingerprint sensing module. The fingerprint sensing module comprises a fingerprint sensor. The fingerprint sensing method comprises the following steps: sensing the finger illuminated by the light source through a fingerprint sensor to obtain a first image; sensing the finger which is not illuminated by the light source through a fingerprint sensor to obtain a second image; and judging the fingerprint image area according to the first image and the second image to generate a fingerprint image.
Based on the above, the fingerprint sensing module and the fingerprint sensing method of the present invention can sense two sensing images of a finger respectively illuminated by a light source and not illuminated by the light source in the same fingerprint sensing operation by the fingerprint sensor, and perform image processing according to the two sensing images, thereby obtaining a fingerprint image with high identifiability.
In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below.
Drawings
FIG. 1 is a schematic diagram of a fingerprint sensing module according to an embodiment of the present invention;
FIG. 2 is a flow diagram of a fingerprint sensing method of an embodiment of the invention;
FIG. 3 is a schematic diagram of an electronic device according to an embodiment of the invention;
FIG. 4 is a flow diagram of image processing according to an embodiment of the invention;
FIG. 5A is a schematic diagram of a first image of an embodiment of the invention;
FIG. 5B is a diagram illustrating a first image after image enhancement according to an embodiment of the invention;
FIG. 6A is a schematic diagram of a second image in accordance with one embodiment of the present invention;
FIG. 6B is a schematic diagram of a mask image according to an embodiment of the present invention;
FIG. 7 is a schematic diagram of a fingerprint image according to an embodiment of the present invention.
Description of the reference numerals
100: a fingerprint sensing module;
110, a processing module;
120, fingerprint sensor;
130, a light source;
140 a storage module;
300, an electronic device;
310: a display panel;
320, fingerprint sensing area;
510. 520, a first image;
511. 521, 611, 621, 711 fingerprint image area;
512. 522, 612, 622, 712 non-fingerprint image areas;
610, a second image;
masking the image 620;
710 fingerprint image;
D1-D3 is direction;
S210-S230, S410-430.
Detailed Description
Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings and the description to refer to the same or like parts.
Fig. 1 is a schematic diagram of a fingerprint sensing module according to an embodiment of the present invention. Referring to fig. 1, the fingerprint sensing module 100 includes a processing module 110, a fingerprint sensor 120, a light source 130, and a storage module 140. The processing module 110 is coupled to the fingerprint sensor 120, the light source 130 and the storage module 140. In the embodiment, the processing module 110 may be a processing chip dedicated to driving the Fingerprint sensor, or an integrated chip, such as a Fingerprint touch driver integrated chip (FTDDI). In the present embodiment, the fingerprint sensing module 100 may be an optical fingerprint sensing module, and the light source 130 is a display panel or an external light source. Alternatively, the fingerprint sensing module 100 may be an off-screen fingerprint sensing module or an in-cell fingerprint sensing module, and the light source 130 is a display panel. The processing module 110 can control the light-emitting state of the display panel (displaying a specific illumination pattern) for generating the first image and the second image as described in the following embodiments.
In the present embodiment, the fingerprint sensor 120 may be an optical fingerprint sensor, and the light source 130 is a visible light source or an infrared light source. In the embodiment, the light source 130 may be a plurality of display pixels in a pixel array of a display panel, and the fingerprint sensor 120 may be a plurality of sensing pixels integrated in the pixel array of the display panel to realize full-screen fingerprint sensing, but the invention is not limited thereto. In one embodiment, the fingerprint sensor 120 may be an in-screen optical fingerprint sensor disposed below the display panel, and the Light source 130 may be a Light-emitting diode (LED) Light source disposed below the display panel. In addition, the Display panel may be, for example, a Light Emitting Diode (led) Display panel, an Organic Light Emitting Diode (OLED) Display panel, a Liquid Crystal Display (LCD), or the like, and the invention is not limited thereto.
Fig. 2 is a flow chart of a fingerprint sensing method according to an embodiment of the present invention. Fig. 3 is a schematic diagram of an electronic device according to an embodiment of the invention. Referring to fig. 1 to 3, the fingerprint sensing module 100 can perform steps S210 to S230 for fingerprint sensing, and the following description will be given by taking the electronic device 300 of fig. 3 as an example. The electronic device 300 may be provided with the fingerprint sensor module 100 as shown in fig. 1 and may provide an on-screen fingerprint sensing function. The display surface of the display panel 310 may be, for example, parallel to a plane extending along the direction D1 and the direction D2, and provide a display screen towards the direction D3, wherein the directions D1-D3 are perpendicular to each other, but the invention is not limited thereto. In the present embodiment, when a finger presses the fingerprint sensing area 320 of the display panel 310 of the electronic device 300, the display panel 310 may display an illumination pattern (pattern) at the position of the fingerprint sensing area 320 first. Accordingly, in step S210, the fingerprint sensing module 100 may sense the finger illuminated by the light source 130 through the fingerprint sensor 120 to obtain a first image (e.g., fig. 5A). Notably, the first image may include a fingerprint image (finger-pressed area image) and a non-fingerprint image (non-fingerprint-pressed area image) surrounding the fingerprint image area because there is an effect that the finger may not completely cover the fingerprint sensing module 100.
Then, the display panel 310 can be switched to display a black pattern at the position of the fingerprint sensing area 320. In this regard, the display panel 310 may be unlit by operating a plurality of pixel units corresponding to the fingerprint sensing area 320, for example, to display the black pattern. Alternatively, the plurality of pixel units corresponding to the fingerprint sensing area 320 are operated to display the lowest brightness. Therefore, in step S220, the fingerprint sensing module 100 may sense the finger without being illuminated by the light source 130 through the fingerprint sensor 120 to obtain a second image (e.g., fig. 6A). It is noted that steps S210 and S220 refer to two sensing operations performed by the fingerprint sensor 120 during one fingerprint sensing operation performed by the finger continuously pressing on the fingerprint sensing area 320 of the display panel 310 (the finger is not separated and moved). The present invention does not limit the order of acquiring the first image and the second image. In one embodiment, the fingerprint sensing module 100 may first acquire the second image and then acquire the first image.
Next, in step S230, the processing module 110 determines the fingerprint image area according to the first image and the second image to generate a fingerprint image. In detail, during the process of acquiring the first image by the fingerprint sensor 120, since the light source 130 illuminates (e.g., the fingerprint sensing area 320 of the display panel 310 is turned on) the finger pressing the fingerprint sensing area 320, the fingerprint image area of the first image acquired by the fingerprint sensor 110 may present an image with obvious fingerprint texture, for example. Moreover, since the fingerprint sensor 120 can also receive the ambient light (or the background light) from the portion of the fingerprint sensing area 320 not pressed by the finger, the first image obtained by the fingerprint sensor 110 has a fingerprint image area and a non-fingerprint image area which are difficult to distinguish. However, in the process of acquiring the second image by the fingerprint sensor 120, since the light source 130 does not illuminate the finger pressed on the fingerprint sensing area 320 (for example, the fingerprint sensing area 320 of the display panel 310 is not illuminated), the brightness of the finger without illumination is lower for the fingerprint sensor 110, and the finger is tightly pressed on a portion of the fingerprint sensor 110, so that the fingerprint image area of the second image acquired by the fingerprint sensor 110 may present an image without fingerprint texture or an image with fingerprint texture that is not obvious or blurred, for example, with darker overall brightness or lower overall gray level. Although the light source 130 does not illuminate the fingerprint sensing area 320 (e.g., the fingerprint sensing area 320 of the display panel 310 is not illuminated), the fingerprint sensor 120 can still receive the ambient light (or the background light) from the portion of the fingerprint sensing area 320 that is not pressed by the finger, so that the second image obtained by the fingerprint sensor 110 has a brighter or higher gray-scale non-fingerprint image area image (which may be an ambient image or a background image). In this regard, the processing module 110 may obtain a fingerprint image (foreground image) having only fingerprint information by analyzing and comparing the first image and the second image to remove the non-fingerprint image of the first image. The detailed manner of acquiring the fingerprint image will be further described in the following embodiments.
FIG. 4 is a flow diagram of image processing according to an embodiment of the invention. Referring to fig. 1 and 4, after the fingerprint sensor module 100 obtains the first image 510 shown in fig. 5A and the second image 610 shown in fig. 6A, the processing module 110 may perform the following steps S410 to S430 to generate a fingerprint image. In step S410, the processing module 110 may first perform image enhancement on the first image 510 to obtain the image-enhanced first image 520 as shown in fig. 5B. In this embodiment, the processing module 110 may remove image noise through image processing operations such as low-pass, high-pass or band-pass filters, or find and enhance the features of the fingerprint image by image processing operations such as image area comparison, edge detection, thinning, and the like. In this regard, the first image 510 of fig. 5A may include fingerprint information in a fingerprint image area 511 and image information in a non-fingerprint image area 512. After the processing module 110 performs image enhancement on the first image 510, the fingerprint information in the fingerprint image area 511 and the image details or features in the non-fingerprint image area 512 may be enhanced. Therefore, compared to fig. 5A, the fingerprint image area 521 and the non-fingerprint image area 522 of the image-enhanced first image 520 of fig. 5B may respectively include fingerprint information and non-fingerprint image content with more obvious or clear image details or features.
Next, in step S420, the processing module 110 may perform binarization processing on the second image 610. In the embodiment, the processing module 110 can generate the mask image 620 as shown in fig. 6B according to the binarization result of the second image 610. In detail, the processing module 110 may set the parameter values of the corresponding pixels in the mask image 620 to a first value (e.g., a value 0) according to a portion of the Analog-to-Digital Converter output code (ADC code) of the pixels in the second image 610 being greater than a threshold value (e.g., an ADC code _ threshold _ 100(full ADC code) and the processing module 110 may set the parameter values of the corresponding pixels in the mask image 620 to a second value (e.g., a value 1) according to a portion of the Analog-to-Digital Converter output code of the other pixels in the second image 610 being less than or equal to the threshold value.
Furthermore, since the finger is not illuminated, the fingerprint sensor 120 only senses the ambient light around the user's body, and the sensing surface of the fingerprint sensor 120 corresponding to the portion covered by the finger cannot receive light (or a very small amount) due to the finger pressing tightly, the non-fingerprint image area 612 of the second image 610 may display an ambient image, but the fingerprint image area 611 will show a darker gray-scale image, for example. Therefore, the processing module 110 can set the parameter values of the pixels in the non-fingerprint image area 622 of the mask image 620 corresponding to the non-fingerprint image area 612 having image information and brightness (ADC code ≧ 100) in the second image 610 to 0 (e.g., the gray-level filled area in fig. 6B) by the above determination method, and the processing module 110 can set the parameter values of the other pixels in the fingerprint image area 621 of the mask image 620 corresponding to the fingerprint image area 611 having no fingerprint image information and brightness (ADC code <100) in the second image 610 to 1 (e.g., the blank area in fig. 6B) by the above determination method.
Then, in step S430, the processing module 110 may generate a fingerprint image according to the image-enhanced first image 520 (or the image-enhanced first image 510) and the mask image 620. in this embodiment, the processing module 110 may multiply a pixel value of each pixel in the image-enhanced first image 520 (or the image-enhanced first image 510) with a parameter value of each pixel in the corresponding mask image 620 to generate the fingerprint image 710 as shown in fig. 7. for example, the image is represented by A3 × 3 mathematical matrix, where the parameters a 11-a 33 of the following matrix (1) are pixel values corresponding to each pixel in the image-enhanced first image 520, and the matrix (2) is a parameter value corresponding to each pixel in the mask image 620. the processing module 110 may multiply parameters at positions corresponding to the matrix (1) and the matrix (2), thus, a matrix (3) is obtained. It is noted that the only remaining parameters of the matrix (3) are the parameters a12, a13, a22, a23 corresponding to the parameter values of 1 in the matrix (2). That is, the fingerprint image 710 will retain the fingerprint information in the fingerprint image area 711, and the non-fingerprint image information in the non-fingerprint image area 712 of the fingerprint image 710 can be effectively removed to obtain a highly recognizable fingerprint image.
In this embodiment, the processing module 110 may further store the fingerprint image 710 to the storage module 140 and as the registration data. However, the present invention is not limited thereto, and in one embodiment, the fingerprint image 710 may also be used for fingerprint verification or other fingerprint applications.
It is noted that in other embodiments of the present invention, when the finger completely presses the fingerprint sensing area 320 as shown in fig. 3, the first image and the second image acquired by the fingerprint sensor 120 may not have the non-fingerprint image area (i.e. the area of the non-fingerprint image area is 0). In contrast, the fingerprint sensing module and the fingerprint sensing method of the present invention can still obtain a fingerprint image with high identifiability (a fingerprint image with only fingerprint information) according to the related image analysis operations and processes explained in the above embodiments.
In summary, the fingerprint sensing module and the fingerprint sensing method of the present invention can sequentially sense two sensing images of a finger respectively illuminated by a light source and not illuminated by the light source in the same fingerprint sensing operation by the fingerprint sensor. In contrast, the fingerprint sensing module and the fingerprint sensing method of the present invention can perform image analysis, processing and comparison according to the two sensing images to remove the non-fingerprint image in the sensing images, and can obtain the fingerprint image only containing the fingerprint information. Therefore, the fingerprint image obtained by the fingerprint sensing module and the fingerprint sensing method of the invention can effectively eliminate unnecessary image information (environmental information), so the fingerprint image of the invention can be used for the back-end processing circuit to carry out rapid and correct fingerprint identification, registration or comparison operation.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (20)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US202063051907P | 2020-07-15 | 2020-07-15 | |
| US63/051,907 | 2020-07-15 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112507960A true CN112507960A (en) | 2021-03-16 |
Family
ID=74921897
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011524267.2A Pending CN112507960A (en) | 2020-07-15 | 2020-12-22 | Fingerprint sensing module and fingerprint sensing method |
Country Status (3)
| Country | Link |
|---|---|
| CN (1) | CN112507960A (en) |
| TW (1) | TWI790516B (en) |
| WO (1) | WO2022011972A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI834384B (en) * | 2022-11-14 | 2024-03-01 | 友達光電股份有限公司 | Biological feature identification module and method of driving the same |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102446271A (en) * | 2010-10-08 | 2012-05-09 | 金佶科技股份有限公司 | Segmented Image Recognition Method and Area Recognition Device |
| CN110472469A (en) * | 2018-05-11 | 2019-11-19 | 辛纳普蒂克斯公司 | The scanning sequence of optimization for biometric sensors |
| US20200065552A1 (en) * | 2018-08-22 | 2020-02-27 | Guangzhou Tyrafos Semiconductor Technologies Co., Ltd | Fingerprint sensing device and fingerprint sensing method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101892013B1 (en) * | 2016-05-27 | 2018-08-27 | 엘지전자 주식회사 | Mobile terminal |
| CN108205665A (en) * | 2018-01-19 | 2018-06-26 | 深圳信炜生物识别科技有限公司 | Electronic equipment |
-
2020
- 2020-12-22 WO PCT/CN2020/138314 patent/WO2022011972A1/en active Application Filing
- 2020-12-22 TW TW109145383A patent/TWI790516B/en not_active IP Right Cessation
- 2020-12-22 CN CN202011524267.2A patent/CN112507960A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102446271A (en) * | 2010-10-08 | 2012-05-09 | 金佶科技股份有限公司 | Segmented Image Recognition Method and Area Recognition Device |
| CN110472469A (en) * | 2018-05-11 | 2019-11-19 | 辛纳普蒂克斯公司 | The scanning sequence of optimization for biometric sensors |
| US20200065552A1 (en) * | 2018-08-22 | 2020-02-27 | Guangzhou Tyrafos Semiconductor Technologies Co., Ltd | Fingerprint sensing device and fingerprint sensing method |
| CN110858296A (en) * | 2018-08-22 | 2020-03-03 | 广州印芯半导体技术有限公司 | Fingerprint sensing device and fingerprint sensing method |
Also Published As
| Publication number | Publication date |
|---|---|
| TW202205147A (en) | 2022-02-01 |
| TWI790516B (en) | 2023-01-21 |
| WO2022011972A1 (en) | 2022-01-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107690653B (en) | Method and device for acquiring fingerprint image and terminal equipment | |
| WO2020063111A1 (en) | Print detection method and apparatus, print image compensation method and apparatus, and electronic apparatus | |
| US11227141B2 (en) | Fingerprint identification device and fingerprint identification method | |
| TWI793448B (en) | Electronic device and operating method thereof | |
| US8610670B2 (en) | Imaging and display apparatus, information input apparatus, object detection medium, and object detection method | |
| US10963665B2 (en) | Method of setting light sources in display panel for optical fingerprint recognition and method of performing optical fingerprint recognition using the same | |
| JP2018005640A (en) | Classifying unit generation device, image inspection device, and program | |
| US11908227B2 (en) | Method and device for reference imaging and optical object recognition | |
| JP2018005639A (en) | Image classification device, image inspection device, and program | |
| CN106934794A (en) | Information processor, information processing method and inspection system | |
| US20220254185A1 (en) | Fingerprint sensing device and operation method thereof | |
| CN100390714C (en) | Display devices that use light beams to input information | |
| WO2020216091A1 (en) | Image processing method and related apparatus | |
| US11551467B2 (en) | Method of obtaining reference image for optical object recognition and method of performing optical object recognition using the same | |
| CN112507960A (en) | Fingerprint sensing module and fingerprint sensing method | |
| EP2919149A2 (en) | Image processing apparatus and image processing method | |
| CN114144812A (en) | Method for generating palm/finger foreground mask | |
| CN112257571B (en) | Biometric image acquisition method and electronic device | |
| CN111046706A (en) | Fingerprint identification method and electronic device using same | |
| CN110858296A (en) | Fingerprint sensing device and fingerprint sensing method | |
| CN117809110A (en) | Training method of defect detection model and defect detection method | |
| US11270097B2 (en) | Electronic device having fingerprint sensing function and fingerprint sensing method | |
| US11347353B2 (en) | Method of performing half-shutter function using optical object recognition and method of capturing image using the same | |
| US9348464B2 (en) | Imaging systems and methods for user input detection | |
| US20220130016A1 (en) | Optical imaging processing method and storage medium |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20210316 |
|
| WD01 | Invention patent application deemed withdrawn after publication |