TW200426698A - Sweep-type fingerprint sensor module and a sensing method therefor - Google Patents

Abstract

A sweep-type fingerprint sensor module includes a microprocessor and a sweep-type fingerprint sensor, which includes a substrate, and a sensing members array, a speed-detecting unit, and a processing circuit on the substrate. The sensing members array is composed of a plurality of fingerprint sensing members. When the finger sweeps across the sweep-type fingerprint sensor, the sensing members array sequentially acquires plural fingerprint fragment images from the finger with a sampling time interval. The speed-detecting unit is composed of first and second plate electrodes. The processing circuit processes and then outputs signals from the sensing members array and the speed-detecting unit. The microprocessor electrically connected to the processing circuit derives a sweeping speed of the finger by the time difference between different time points when the plate electrodes contact the finger, determines the sampling time interval and then stitches the fingerprint fragment images into a complete fingerprint image.

Description

200426698

V. Description of the invention (1) [Technical field to which the invention belongs] Group and its sensing method Fingerprint sensor The present invention relates to a sliding fingerprint sensor module method, especially to a sliding module with a speed sensing unit And its sensing method. [Prior art] The conventional fingerprint reading method is to use an ink-stained finger to press on the paper, and then use an optical scanner to sweep the broad-brushed teeth to the brain i. + &, enter the fingerprint into the electronic paper, and then compare it with the fingerprint pattern in the library. However, the biggest disadvantage is that it cannot achieve immediate processing; / 钺 多 卽 睥 切 嘹 μ + $ γ, so it cannot meet the needs of more and more immediate, such as: network belt electronic products confidentiality, 1C card personal identity ^ π e-commerce, real-time fingerprint reading method becomes i, security system and so on. Surgery. Traditionally, the key technology in the market can be identified using optical patterns. However, it has too much volume to read fingerprints in real time. Chip-type fingerprint sensors have been developed to meet the needs; Disadvantages of semiconductors. Brother served the above-mentioned optical sensor, because the size of the finger is limited, the conventional measurement area is at least larger than that. A f said that the sensing effect of the chip-type private pattern sensor is limited to the cost of packaging and testing of silicon integrated circuit manufacturing in a β-inch wafer, which will make Star " 50 to 70 effective chips, Coupled with a price of more than 10 yuan, this will limit the price of the A-line sensor to at least greater than that of notebook computers, mobile phones, and mobile phones: in various consumer electronics products, such as ?, 啻 收 < 〇 □, since > -200426698

Therefore, the traditional two-dimensional wafer-type index can be reduced to increase the output of the effective daily film / heart-dimensional area

^ Eight Principles: Slide your finger across the surface of the chip, scan the AA car buckle AA, and then fingerprint each of the captured fragments. &&凡; Fan Chengzheng is a hand buttoned Nai Cai Cai patterned shirt plus φ Focus on the fingerprint image. A into m Fan

Mainguet in U.S. Patent No. 6,289 1 1 4 is a public fingerprint (thermal) or piezoelectric material (pressure), which is a kind of sliding fingerprint sensor and a sliding fingerprint sensor. Xi ~, law, the main disadvantage is that ... it is not possible to judge the speed of the finger sliding, so it is necessary to take a considerable number of fragment fingerprint images, plus

:: Reorganized, complete fingerprint image. It is expected that f requires a powerful micro-processing state, a large memory, and easily leads to reorganization errors. —The conventional sliding fingerprint sensor only knows to reduce the area of the sensor by reducing the number of sensing elements in the γ-axis direction (meaning the direction in which the finger slides), so that the size in the Υ-axis direction is between 〇 · 8 to 1 · 6min, so the number of captured fingerprint images is quite large. FIG. 1 is a schematic diagram showing a finger sliding over a conventional sliding fingerprint sensor. As shown in Figure 1, ‘finger 丨 20 slides over the sliding fingerprint at a speed v along the γ axis.

The sensor 11 0 ′ enables the sliding fingerprint sensor 110 to obtain a plurality of segment fingerprint images. FIG. 2 is a schematic diagram of the reorganization of a segment fingerprint image captured by the fingerprint sensor of FIG. 1. As shown in FIG. 2, the captured segment fingerprint images π (1) to I KN) can be reconstructed into a complete fingerprint image of the finger 120. Since the number of sensing elements of the conventional sliding fingerprint sensor in the γ-axis direction is too small, tens to hundreds of images I I (1) to 11 (N) must be stored. Sense of sliding fingerprint

200426698 V. Description of the invention (3) ___ When designing the sensor, the designer only knows the number of sensing elements in the contraction / direction), so the area of the sensor (reducing the Y axis from 0.8 to 1.6mm) In addition, most of the size of the array and array are the sliding speed of the finger, and the fingerprint sensor with the security factor does not detect the overlapping areas ΑΑ (1) to ΑΑ (Ν-1). Kao Xia 'causes the number of images and difficulty required for image reconstruction between each image. The product is too large and further increases the aforementioned disadvantages of image synthesis. Traditionally, the reconstructed image is used as a characteristic private pattern sensor module. It is difficult, therefore, that there is already a way to go to 7 σ to get 'and even subsequent recognition. The method of directly converting the grayscale image to frequency using frequency spectrum' will capture a large number of picture-taking actions. Iron knife cloth 'this The advantages of this method are that it does not require the surface of the wafer to be affected and the error is affected. Refers to the problem that this case intends to solve. [Contents] Therefore, ^ The number of sliding fingerprints provided by the system is provided-a type of sensor that can reduce the reorganized image eight button pattern sensor. The present invention 3L _ ^ ^ ^ ^ Force-the purpose is to provide a method that can distinguish fingers The authenticity of a sliding fingerprint sensor module. In order to achieve the above objectives, the present invention provides a sliding fingerprint sensor core group i "including a microprocessor and a sliding fingerprint sensor. Sensor. The fingerprint sensor is a substrate, and a sensor element array, a speed sensing unit, and a processing circuit located on the substrate. The sensor element array is composed of a plurality of fingers.

Page 8 200426698 V. Description of the invention (4) '" ------ The texture of 1 yuan is used to sense the fingerprint of a finger and is continuous at a sampling time interval. Take multiple fingerprints of the finger. image. The speed sensing unit is composed of a first and a second electrode plate. The processing circuit processes and outputs signals from the sensing element array and the speed sensing unit. The microprocessor and the processing circuit are electrically connected to obtain the sliding speed of the finger from the time difference between the contact between the electrode plates and the finger, and then determine the sampling time interval, and recombine the special segment image into a complete fingerprint image. . To achieve the above object, the present invention also provides a sensing method of a sliding fingerprint sensor module, which includes the following steps: detecting a sliding speed of a finger; determining a sampling time interval according to the sliding speed; The plurality of fragment fingerprint images of the finger are continuously captured at the sampling time interval, so as to output a plurality of fragment fingerprint signals corresponding to the fragment fingerprint images; and the plurality of fragment fingerprint signals are processed and reconstructed into a complete fingerprint image. . By detecting the sliding speed of the finger, the number of captured fingerprint images can be effectively reduced, thereby simplifying the reorganization process and reducing costs. [Embodiment] Fig. 3 shows a schematic diagram of a finger sliding over the sliding fingerprint sensor of the present invention. FIG. 4 is a schematic diagram of the weight of a segment fingerprint image captured by the fingerprint sensor of FIG. 3. As shown in Figures 3 and 4, when the finger 9 slides through the sliding fingerprint sensor 10 at a speed V, the sliding fingerprint sensor 10 assists in detecting the speed V of the finger 9 and captures it based on the speed v. Take a plurality of fragment fingerprint images I (1) to I (N), where N is a positive integer. The overlapping area of the fingerprint images of two adjacent fragments is A (1) to A (N-1), which is helpful for comparing these features by using feature point comparison.

Page 9 200426698 V. Description of the invention (5) Fragment fingerprint images are recombined. The above-mentioned sensor can be implanted into any dry stage where the finger 9 is placed on the Xiao platform and the clothes are placed along the arrow side. when

So, Continue: Get the fragment fingerprint image, which will be processed at last ~: The entire fingerprint image will be processed if there are no photos. Because the finger can be regarded as first-class' " = or constant-speed movement within a certain distance, if you can understand the strict ^ PV, it will be very helpful to adjust the time interval of image capture. 'Most degree |' to reorganize. This can eliminate the need for powerful micro / profits and a large amount of memory, and at the same time can greatly reduce the chance of identification errors: low cost of sensors and identification systems, and application level of energy. GA Na Figure 5 shows a top view of a sliding finger according to a first embodiment of the present invention. Fig. 6 shows a cross-sectional view along line L6-u of Fig. 5. Fig. 6 is a side view of a sliding fingerprint sensor according to the first embodiment of the present invention in operation. It is worth noting that the size of the finger and the sensor in Figure 7 are plotted according to the international scale. As shown in FIGS. 5 to 7, the sliding fingerprint sensing and measuring module of the present invention includes a microprocessor 丨 丨 and two sliding fingerprint sensors 10 electrically connected to the microprocessor 丨 丨. The sliding fingerprint sensor 10 includes a substrate i, a sensor element array 2, a speed sensing unit 3, a processing circuit 4, a resistor, a sensor t, and a plurality of solder pads 6. The solder pads 6 are electrically connected to the micro-position ‘Is 11. The sensing element array 2 is located on the substrate 1 and is composed of a plurality of fingerprint sensing elements 21 (only one sensing element is drawn for simplicity of description) in a two-dimensional array. The fingerprint sensing element 21 may be a capacitive, pressure or temperature difference sensing element, as disclosed by the applicant in the following patent application

200426698 V. Description of the invention (6) Exposed 1. Republic of China invention patent application number 9 1 1 0 68 0 6, application date 2 0 2/4/3, the name of the invention is: capacitive fingerprint reading chip; 2 · Republic of China invention patent application number 9 1 1 1 0443, application date 2002/5/17, the invention name is: pressure type fingerprint reading chip and its manufacturing method; and 3. Republic of China invention patent application number 90113755, application At 2 0 1/7/6, the invention name is: Design and manufacture of temperature difference induction fingerprint recognition chip. In order to match the size of the finger 9, the X-axis (horizontal) size of the sensor element array 2 is at least greater than 8mm, and the optimized Y-axis (longitudinal) size is between 2 · 5 and 3 · 5mm. Later. The plurality of sensing signals from the sensing element array 2 are processed by the processing circuit 4 and communicated with the outside via the input / output pad 6. The processing circuit 4 basically includes a logic control circuit, a variable gain amplifier, and an analog digital converter. The related architecture is also described in the above-mentioned "capacitive fingerprint reading chip" and "pressure fingerprint reading chip and manufacturing thereof" Method "patent application. 2. The sensing element array 2 senses and slides the fingerprint images of a plurality of segments of the finger continuously at the same time interval by sliding the fingerprint of the finger 9 (FIG. 3) thereon, thereby rotating the fingerprints corresponding to the segments. Fingerprint signal of multiple clips in the image. In order to solve the shortcomings of the conventional technology, the present invention integrates the speed sensing unit 3 into a slide-type fingerprint sensor. The degree sensing unit 3 is also located on the substrate 1, and is composed of a first electrode plate 31 and a second electrode plate 32. the first

200426698 V. Description of the invention (7) and the second electrode plates 31 and 32 are substantially flat with each other. These electrode plates are located at the sensing distance-a predetermined distance I and the right side is a large one, ▼ a soil morning and evening j Z (upper and lower sides), and there are approximately 4 Array 2 in the χ-axis direction plate 3 1 loses' ^ an electric ^ ^ ^ 9 Α trophy, ^ ^ a second time signal, the second electrode plate =: this: refers to 9 contact, out A second time signal. Comment. "'Finger 9 is along the γ-axis, and the top of the first electrode plate 31 is described as one or two ^ days'. Finger 9 will pass the reason first, please refer to the above" Capacitance capacitor (Related circuit And the original (This: Yes: Two .: Sending a pulse can turn on the power of the fingerprint sensor (this can reduce the work of the sensor when it is not in use, it will slide over the surface of the sensor element array 2 and reach the second punch). Because you already know the first and second electrode plates 31 and D1, and then calculate the time difference between the two trigger pulses, you can get the sliding speed v of the finger 9. Yu Taiyuan A office processor u required the above implementation In the example, 'sliding speed V is calculated from the micro-to-ΐϊϋn: The sliding speed of finger 9 can be used to determine the sampling time interval of receiving the μ-grain image of the mother sheet, and then the fragment fingerprint image can be received and processed. Storing too many pieces of fingerprint images' 纟 does not require a powerful microprocessor, which is beneficial to reducing costs. Therefore, the inventors of this case weighed the dual considerations of the characteristics and cost of fingerprint sensors, The best in the γ-axis direction of element array 2 Dimension defined between 2. 5 to 3. 5mm. In the present specification 5〇〇 DPI embodiment, sector size is the size of the X-axis direction 'Y-axis direction is 10mm [32_ is (in terms of

Page 12 200426698 V. Description of the invention (8) 200 * 64 pixels). This is because when the two fingerprints Γ, the axis weight square Λ = Γ meters ... The length of the sensor element array in the y-axis direction of the A (1) to AU — Dg technology shown in Figure 4 is shown in Figure 4 Only 0.2% of the area is wasted in the overlapping area of the picture, so a large mm's are needed: Minato:-a complete image. And the present invention cooperates with the finger & 1 'gate to define the optimized Y-axis size of the sensing element array 2 from 2.5 to 3.3, and the stitched image is shown in FIG. 4. Except for the overlapping area with = The image of the weight = area is 15 to 25mm in the direction of the γ car. Because of the image. 3 to 5 images, and 7 to 9 images, you can piece together a complete image. Not only can the number of required fragment fingerprint images be greatly reduced, the H mouth J spear B9 can be recombined with a general and stable feature point comparison method. The processing circuit 4 is connected to the sensing element array 2 and the The speed sensing unit 3 is used to receive and process the fingerprint signals of the plurality of fragments, the first time ^ ~, and the second time signal, and output the processing through the pads ^ ^ u 到The microprocessor 11. The microprocessor 11 obtains one of the fingers 9 according to the first time signal, the second time signal of the kiss kisser, and the predetermined distance D1; bone ^ 鸯 ^ r ^ p

, X v 'and determine the sampling time interval according to the sliding speed V, and further process the re-aged I & I segment fingerprint signal and reassemble it into a complete fingerprint image. 0 The impedance sensor 5 is located on the substrate 1 and By sensing a resistance value of the finger 9, the product i and u help identify the authenticity of the finger 9. The impedance sensor 5 includes a pair of naked ^ frS A, smart metal strip electrodes 51 and 52. When the finger 9 is placed above the two electrodes 51 and 52, π, ^ can detect the resistance value of the skin of the finger 9 R and recorded in microprocessing

Page 13 200426698 V. Description of the invention (9) In Miaozhong, the resistance value of the fake finger and the flower that pass through the microprocessor u is different, so the authenticity of the finger can be identified at W8. Figure 8 shows the top view of the door according to the present smoke. As shown in Figure 8: "The first embodiment is the same as the sliding fingerprint sensor in the second embodiment": The embodiment is similar to the first embodiment, not φ, but μ — Φ Γ For example, the second electrode plate 32 is located on the sensing element array 2 ρ, and the M-diode plate 31 is located on one longitudinal side (upper side) of the sensing element array 2. An electrode plate 32 can be integrated with the metal mesh of the sensing element array and used. : The sliding fingerprint sensor that is not according to the third embodiment of the present invention ": Two ports: As shown in 9-1, the third embodiment is similar to the first embodiment. The first and second electrode plates 31 and 32 of the embodiment are both located on the same longitudinal side (upper side) of the sensor element array 2. In the same way, both the first and second electrode plates 31 and 32 can also be used for sensing. Measure in το array 2. 囷 1 〇 ”, the flow of the sensing method of the sliding fingerprint sensor of this book: as shown in Figure 1 〇 The invention also provides a sliding fingerprint sensor The sensing method includes the following steps: Step S1: Detecting the sliding speed ν of the finger 9: First, when the finger g 1 touches the first electrode plate 31, a first time signal is output; then, when the When the finger 9 contacts the second electrode plate κ separated by a predetermined distance M from the first electrode plate 31, the second time signal is output; and then the predetermined distance D 丨 is divided by the difference between the first and second time signals to Obtain the sliding speed V; Step S20: Determine a sampling time interval according to the sliding speed V. First, use the fingerprint image of each segment Along the sliding direction of the image producing long fingers (K

200426698 V. Description of Invention (The γ-axis length of column b of the element array) minus the overlapping length of the two adjacent fingerprint images (determined by the image processing software of the heart pattern) to obtain the effective length. Divide the effective length by the sliding speed to obtain the sampling time interval; Step S30: Continuously capture the fingerprint image of the plurality of solid segments of the finger 9 at the sampling time interval to output the fingerprints corresponding to the segments The image of the plurality of fragmented fingerprint signals of the image, ... ^ Step S40: The plurality of fragmented fingerprint signals are processed and reassembled-a complete fingerprint image; and step s50: The impedance of the finger is detected to identify the straightness of the finger. The invention determines the sampling time interval of fragments, images, and scenes by detecting the sliding speed of a finger, thereby effectively reducing the number of fragments of fingerprint images and simplifying the image reorganization process, thereby reducing the cost of the sensor. The specific embodiments proposed in the detailed description of the preferred embodiments are only used to explain the technical content of the present invention, rather than limiting the present invention to the above embodiments in a narrow sense, without exceeding the spirit of the present invention and the following In the case of applying for a patent, various changes and implementations are within the scope of the present invention.

Page 15 200426698 Brief description of the drawings Figure 1 shows a schematic diagram of a finger sliding over a traditional sliding fingerprint sensor. FIG. 2 is a schematic diagram of the reorganization of a segment fingerprint image captured by the fingerprint sensor of FIG. 1. Figure 3 shows a schematic diagram of a finger sliding over a sliding fingerprint sensor of the present invention. FIG. 4 shows the unintended reorganization of the fingerprint image of the segment captured by the fingerprint sensor of FIG. 3. FIG. 5 shows a top view of a sliding fingerprint sensor module according to a first embodiment of the present invention. FIG. 6 shows a cross-sectional view taken along line L6-L6 of FIG. 5. FIG. Fig. 7 shows a side view of the sliding fingerprint sensor according to the first embodiment of the present invention during operation. FIG. 8 shows a top view of a sliding fingerprint sensor according to a second embodiment of the present invention. FIG. 9 shows a top view of a sliding fingerprint sensor according to a third embodiment of the present invention. FIG. 10 shows a flowchart of a sensing method of a sliding fingerprint sensor according to the present invention. [Explanation of Symbols of Components] 2 ~ sensor element array 4 ~ processing circuit 6 ~ solder 8 ~ capacitive sensor element array 1 ~ substrate 3 ~ speed sensing unit 5 ~ impedance sensor 7 ~ pressure sensor element Array

Page 16 200426698 Brief description of drawings 9 ~ Fingers 10-'Sliding fingerprint sensor 11 ~ Microprocessor 21-'Fingerprint sensor unit 31 ~ First electrode plate 32-'Second electrode plate 51 ~ Metal strip Electrode 52 ~ Metal strip electrode 71 ~ Pressure sensor 81 ~ Capacitance sensor 11 0 ~ Slide fingerprint sensor 1 2 0 ~ Finger II (1)-II (N) ~ Fragment fingerprint image I ( 1)-I (N) ~ fragment fingerprint image AA (1) -AA (N-1) ~ overlapping area A (l) -A (N-1) ~ overlapping area

Page 17

Claims (1)

200426698 Contains 1 * a sliding fingerprint sensor module, including: a microprocessor; and a sliding fingerprint sensor, which is electrically connected to the microprocessor and includes a substrate; a sensor element array located in the The basic measurement array is arranged in a two-dimensional array, and a plurality of fragments of the finger are taken through a fingerprint of one of the fingers to obtain a plurality of fragments of the finger. The image of the fingerprint is a plurality of fragments. It is formed with a second electrode plate, which is parallel and separated by a predetermined distance. The second plate is composed by a complex, and the sensing element outputs a check mark with a sampling time. On the substrate, one and the first When the 21 electrode plate outputs a first time signal, the second electrode plate outputs a 12 time signal; and a processing circuit connected to the sensing element for receiving, processing and outputting the first time signal, And the second time is based on the first time signal and the sliding speed of one of the fingers at the second time, and according to the interval, the fingerprints of the plurality of segments are further corrected: a fingerprint image. 2 · As set in item 1 of the scope of the patent application, wherein the sensor element array is successively captured along the electrode by the electrode and the plurality of fingerprint sensor array sensing slide intervals to the first electrode plate. In essence, when the finger is in contact with the finger, the array and the plurality of pen signals, the signal, and the sliding speed number are described in the sliding finger sliding sensing unit electrical pattern signal, and the microprocessor obtains the speed segment index according to a predetermined distance. The size of the direction in which the sampling time is determined in advance and recombined into a complete fingerprint sensor module Page 18 200426698 6. Scope of patent application The quality range is 2.5 to 3.5 mm. 3. The sliding fingerprint sensor module according to item 1 of the scope of patent application, wherein the first and second electrode plates are respectively located on an upper side and a lower side of the sensing element array. 4. The sliding fingerprint sensor module according to item 1 of the scope of the patent application, wherein both the first and first electrode plates are located on the same longitudinal side of the sensing element array. 5 · The sliding fingerprint sensor module according to item 1 of the scope of patent application, wherein both the first and second electrode plates are located in the sensing element array. 6 · as item 1 of the scope of patent application In the sliding fingerprint sensor module, one of the first and second electrode plates is located in the sensing element array, and the other is located on a longitudinal side of the sensing element array. 7. The sliding fingerprint sensor module according to item 1 of the scope of patent application, wherein the sliding fingerprint sensor further comprises an impedance sensor located on the substrate for sensing one of the fingers Resistance value to help identify the authenticity of the finger. 8. The sliding fingerprint sensor module according to item 1 of the patent application scope, wherein the impedance sensor comprises two long electrodes. 9. The sliding fingerprint sensor module according to item 1 of the scope of patent application, wherein the sliding fingerprint sensor further comprises a plurality of solder pads formed on the substrate for power supply and connection to the Microprocessors. 10. The sliding fingerprint sensor module as described in item 1 of the scope of patent application 200426698 6. The scope of patent application group, wherein the sensing element array is arranged by a plurality of capacitive sensing elements in a two-dimensional array. Make up. 11. The sliding fingerprint sensor module according to item 1 of the scope of patent application, wherein the sensing element array is composed of a plurality of temperature difference sensing elements arranged in a two-dimensional array. 12. The sliding fingerprint sensor module according to item 1 of the scope of patent application, wherein the sensing element array is composed of a plurality of pressure-type sensing elements arranged in a two-dimensional array. 13. —A method for sensing a sliding fingerprint sensor module, including the following steps: detecting a sliding speed of a finger; determining a sampling time interval according to the sliding speed; continuously capturing the finger at the sampling time interval The plurality of segment fingerprint images to output a plurality of segment fingerprint signals corresponding to the segment fingerprint images; and processing the plurality of segment fingerprint signals and recombining them into a complete fingerprint image. 14. The sensing method of the sliding fingerprint sensor module according to item 13 of the scope of the patent application, wherein the step of detecting the sliding speed of the finger includes: when the finger contacts a first electrode plate Output a first time signal; when the finger contacts a second electrode plate that is separated from the first electrode plate by a predetermined distance, output a second time signal; and Page 20 200426698 6. Scope of patent application Divide the predetermined distance by the difference between the first and second time signals to obtain the sliding speed. 15. The sensing method of the sliding fingerprint sensor module as described in item 13 of the scope of the patent application, wherein the step of determining the sampling time interval according to the sliding speed includes: along the fingerprint image of each segment An effective length is obtained by subtracting an overlapping length of two adjacent pieces of fingerprint images from an image length in a finger sliding direction; and dividing the effective length by the sliding speed to obtain the sampling time interval. 16. The sensing method of the sliding fingerprint sensor module as described in item 15 of the scope of patent application, wherein the range of the image length is substantially between 2.5 and 3.5 mm. 17. The sensing method of the sliding fingerprint sensor module according to item 15 of the scope of the patent application, wherein the range of the overlap length is substantially between 400 and 800 microns. 18. The method of sensing a sliding fingerprint sensor module as described in item 13 of the scope of patent application, further comprising the following steps: Detect an impedance of the finger to identify the authenticity of the finger 9 Page 21