Information Processing Apparatus, Information Processing Method, and Program

Abstract

To suppress a deterioration in fingerprint detection performance by making it possible to adjust a method for processing a signal detected by a fingerprint sensor in accordance with a propagation characteristic of an ultrasonic wave even in the case that a protective film is stuck to the surface of an information processing device.SOLUTION: An information processing device includes a housing, an ultrasonic sensor capable of detecting a fingerprint of a finger brought into contact with the surface of the housing, and a control part. The control part determines whether it is necessary to adjust a method for processing a signal detected by the ultrasonic sensor, and executes the adjustment of the method for processing the signal when it is determined that the adjustment is necessary.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to an information processing apparatus.

Background Art

[0002] Examples of portable information processing apparatuses include wireless terminals such as smartphones and mobile phones, tablet terminals, and notebook personal computers. Some of these information processing apparatuses are provided with fingerprint sensors for authenticating users.

[0003] As the fingerprint sensor, an ultrasonic type, an optical type, a capacitance type, or the like is adopted. Among these, the ultrasonic fingerprint sensor is provided inside the housing of the information processing apparatus, emits ultrasonic waves to a finger in contact with the surface of the housing such as a display through the housing base material such as the display, and detects a reflected wave from the finger surface. The fingerprint sensor generates a fingerprint image from the two-dimensional distribution of the signals received the reflected wave.

[0004] By the way, recently, after a portable information processing apparatus is sold to a user, the user may separately purchase a protective film and superimpose and attach it to the surface of, for example, the display of the information processing apparatus.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when a protective film is attached to the surface of the display of the information processing apparatus, the length of the path of the ultrasonic wave that reaches the finger from the fingerprint sensor, is reflected, and returns to the fingerprint sensor, and the material included in the path change. As a result, the propagation characteristics of the ultrasonic wave change, which affects the detection result of the fingerprint sensor.

[0007] Therefore, one aspect of the disclosed embodiments is to be able to adjust the processing method of the signal detected by the fingerprint sensor in response to the propagation characteristics of ultrasonic waves even when a protective film is attached to the surface of the information processing device, thereby suppressing a decrease in fingerprint detection performance.

Means for Solving the Problem

[0008] The disclosed embodiments are exemplified by an information processing device. This information processing device includes a housing, an ultrasonic sensor capable of detecting a fingerprint of a finger in contact with the surface of the housing, and a control unit. The control unit determines whether it is necessary to adjust the processing method of the signal detected by the ultrasonic sensor, and when it is determined that the adjustment is necessary, executes the adjustment of the processing method of the signal.

[0009] Here, the adjustment of the processing method of the signal may include causing the ultrasonic sensor to emit ultrasonic waves, detecting a reflected wave of the emitted ultrasonic waves, and determining a time interval for receiving the reflected wave at the time of fingerprint detection from the temporal change of the received signal of the reflected wave after the time of emitting the ultrasonic waves.

Effect of the Invention

[0010] This information processing device can adjust the processing method of the signal detected by the fingerprint sensor in response to the propagation characteristics of ultrasonic waves even when a protective film is attached to the surface of the information processing device, thereby suppressing a decrease in fingerprint detection performance.

Brief Description of the Drawings

[0011]

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DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, with reference to the drawings, an information processing apparatus 10 according to an embodiment will be exemplified. Specifically, the information processing apparatus 10 is a wireless terminal such as a smartphone, a mobile phone, a tablet terminal, a notebook personal computer, or the like. The information processing apparatus 10 disposes a fingerprint sensor in the housing below the display screen and can perform fingerprint authentication by placing a finger on the screen. Such fingerprint authentication is called in-screen authentication.

[0013] <Features and Issues of Ultrasonic Fingerprint Sensors> Referring to FIGS. 1 to 3, the features of the ultrasonic fingerprint sensor will be described. FIG. 1 is a diagram illustrating the reading principle of the ultrasonic fingerprint sensor. As shown in FIG. 1, this fingerprint sensor has a layer (piezoelectric element layer) in which piezoelectric elements are arranged on the back surface of a housing substrate such as a display. Each piezoelectric element in the piezoelectric element layer has a transmitter section and a receiver section. The transmitter section (transmission device) vibrates the piezoelectric element by an input electrical signal, emits ultrasonic waves as acoustic waves that continue for a predetermined time in a pulse shape, and propagates through a substrate such as a display. The receiver section (reception device) generates an electrical signal by the vibration of the reflected wave that has propagated through the substrate and is reflected by the finger. Note that the portion of the piezoelectric element layer including the transmitter section and the receiver section is also referred to as a transceiver section or a transducer section.

[0014] In this way, the ultrasonic fingerprint sensor is based on the basic principle of transmitting sound waves toward the fingertip and capturing the reflected sound waves. And the ultrasonic fingerprint sensor forms an image of the fingerprint on the surface of the finger based on the difference in the reflected wave signals (amplitude, energy) at each position of the piezoelectric element array, which is based on the difference in the acoustic resistance of the skin, air, and fingerprint ridges. That is, as shown in FIG. 1, the convex portions of the fingerprint have a large transmission component of ultrasonic waves and few reflected waves. On the other hand, the concave portions of the fingerprint have many reflection components. The ultrasonic fingerprint sensor detects the fingerprint based on the strength of the electrical signal detected due to the difference in the reflected wave signals caused by these.

[0015] FIG. 2 is a diagram illustrating a reception window at the time of detecting a reflected wave by the ultrasonic fingerprint sensor. Further, FIG. 2 illustrates the material of the medium that intervenes between the fingerprint sensor in an information processing device such as a smartphone and the finger that is the object of fingerprint detection and serves as the propagation path of ultrasonic waves. Here, the case where an ultrasonic fingerprint sensor is mounted on the lower side of the display, for example, on the back surface of a cover glass in a smartphone or the like is illustrated.

[0016] When an information processing device such as a smartphone detects a fingerprint image using a fingerprint sensor configured as shown in Figure 2, for image quality improvement, ultrasonic waves are emitted from the fingerprint sensor and the reflected waves are detected within a time interval after a predetermined time has elapsed. This time interval is called a reception window. That is, the information processing device tunes the time when the sound waves reflected from the surface of the finger in contact with the display, that is, the cover glass surface of the display, return according to the thickness of the display and the material of the components.

[0017] Between the piezoelectric element layer of the fingerprint sensor and the cover glass surface of the display, there is a medium of the material exemplified on the right side of Figure 2. In the example of Figure 2, the following are exemplified on the cover glass: Top OCA (adhesive), Polarizer Stack (polarizer), PSA (pressure-sensitive adhesive), Bottom OCA, OLED Panel (organic EL panel), Backplate PSA, Backplate PET (polyethylene terephthalate). As shown in the figure, the ultrasonic waves emitted from the fingerprint sensor pass through these media, reach the finger, and a part of them is reflected and returns to the fingerprint sensor. On the path through which the ultrasonic waves pass, each material is in contact with each other at their interfaces, forming the interfaces. As a result, part of the ultrasonic waves is reflected at each interface and returns to the fingerprint sensor before reaching the finger. The reflected waves reflected at the interfaces of such each material become noise with respect to the reflected waves reflected from the surface of the finger. Therefore, the information processing device sets the time interval mainly composed of the reflected waves reflected from the surface of the finger as the reception window, and limits the detection of the reflected waves to the reception window. Thereby, the information processing device selects the section with a high signal component obtained from the surface of the finger and improves the image quality. surface from which the reflected waves are mainly reflected as the reception window, and limits the detection of the reflected waves to the reception window. Thereby, the information processing device selects the section with a high signal component obtained from the surface of the finger and improves the image quality.

[0018] However, when a user arbitrarily selects and attaches a protective film onto the cover glass, the time for the reflected wave to return is shifted by the protective film. As a result, the image quality of the image acquired by the information processing apparatus using the fingerprint sensor deteriorates, and the authentication performance deteriorates. In this case, it is also conceivable to change the reception window, which is a tuning parameter of the fingerprint sensor, according to the protective film. However, it is difficult for the fingerprint sensor or the information processing apparatus to recognize the presence or absence of the protective film. Further, even if the fingerprint sensor or the information processing apparatus recognizes the presence of the protective film, it is difficult to recognize the characteristics of the protective film, such as the material and thickness of the protective film, that affect the propagation of ultrasonic waves.

[0019] In the following plurality of embodiments described below, an information processing apparatus that solves the above problems is exemplified. That is, in each of the following embodiments, when no finger is in contact with the fingerprint detection area on the display surface, the information processing apparatus detects a reflected wave that is reflected at the interface between the protective film and the air among the ultrasonic waves emitted from the fingerprint sensor. The information processing apparatus determines an appropriate reception window or corrects the reception window by identifying the reflected wave from the interface between the protective film and the air. With the start time and window width of the reception window determined in this way, the information processing apparatus can detect fingerprints with good image quality even when the protective film is attached to the display.

[0020] <First Embodiment> Hereinafter, with reference to FIGS. 3 to 7, the information processing apparatus 10 according to the first embodiment will be described.

[0021] (Configuration) Figure 3 is a hardware configuration diagram of the information processing apparatus 10. The information processing apparatus 10 includes a CPU 1, a memory 2, a touch screen sensor 3, an OLED 4 (organic EL display), and an ultrasonic fingerprint sensor 5. Further, the information processing apparatus 10 includes a wireless communication unit 11, a receiver 12, a speaker 13, a microphone 14, and a camera 15. Note that the wireless communication unit 11, the receiver 12, the speaker 13, the microphone 14, and the camera 15 are connected to the CPU 1 through their respective interfaces.

[0022] The CPU 1 is connected to the memory 2, and the memory 2 stores executable software code. The CPU 1 executes each process of the information processing method of the information processing apparatus 10 according to the software code stored in the memory 2 and provides functions. The CPU 1 and the memory 2 are an example of a control unit.

[0023] Also, the CPU 1 controls the OLED 4 to display information to the user and provide various outputs. Further, the CPU 1 has a touch screen sensor on the OLED 4, detects a touch screen operation from the user, and executes various processes using the operation as an input. The OLED 4 is an example of a display unit.

[0024] The ultrasonic fingerprint sensor 5 is located on the lower surface of the OLED 4 and reads the user's fingerprint through the touch screen sensor 3 and the OLED 4. The CPU 1 acquires image data from the ultrasonic fingerprint sensor 5. Then, the CPU 1 performs image processing on the acquired image data. The CPU 1, for example, compares the image-processed image with the template fingerprint stored in the memory 2 to determine whether the image acquired by the ultrasonic fingerprint sensor 5 matches the template fingerprint.

[0025] The wireless communication unit 11 accesses, for example, the wireless communication network of a communication carrier to execute wireless communication. Also, the receiver 12, the speaker 13, and the microphone 14 are used for input and output of voice or sound. The user makes a call through the receiver 12, the speaker 13, and the microphone 14. The camera 15 is used for taking pictures.

[0026] FIG. 4 is a front view illustrating the appearance of the information processing apparatus 10. In FIG. 4, the left side illustrates the appearance without the protective film 30, and the right side illustrates the appearance with the protective film 30 attached. As shown in FIG. 4, on the front surface of the housing of the information processing apparatus 10, OLED 4 is provided. Also, OLED On 4, the touch screen sensor 3 is superimposed on the upper surface side. Note that in FIG. 4, OLED The cover glass covering 4 and the touch screen sensor 3 is omitted. OLED In the rectangular area indicated by the dotted line at the lower part of the screen of 4, OLED An ultrasonic fingerprint sensor 5 is built in the housing on the back of 4. The fingerprint sensor 5 detects a fingerprint from a finger that has contacted the rectangular area surrounded by the dotted line of the touch screen sensor 3 (and the cover glass). The rectangular area surrounded by the dotted line in FIG. 4 will be referred to as the detection area. The fingerprint sensor 5 can be said to be an ultrasonic sensor that can detect the fingerprint of a finger that contacts the surface of the housing. Also, the detection area illustrated by the dotted rectangle in FIG. 4 can be said to be a partial area of the screen of the display unit. That is, the fingerprint sensor 5 detects the fingerprint of a finger that contacts this detection area.

[0027] As illustrated on the right side in FIG. 4, the protective film 30 OLED Covers the front surface of the screen of 4. Also, in the protective film 30 on the right side of FIG. 4, the portion covering the detection area of the fingerprint sensor 5 is surrounded by a dotted line. The protective film 30 has two holes 31A and 31B in the portion covering the detection area of the fingerprint sensor 5. When collectively referring to the two holes 31A and 31B, they are simply called holes 31. Since the position of the detection area of the fingerprint sensor 5 is fixed to the housing, information (for example, identification information) can be defined by the positions of the two holes 31A and 31B. That is, the fingerprint sensor 5 and the information processing apparatus 10 recognize the presence of the protective film 30 from the positions of the holes 31A and 31B and can identify individual protective films 30.

[0028] (Mechanism for adjusting the reception window) FIG. 5 illustrates the ultrasonic reflection situation at the portion of the cover glass 21 of the information processing apparatus 10 where the protective film 30 is attached and the portion where it is not attached. Here, the protective film 30 includes a film base material 30A on the surface side and an adhesive 30B. As already described, ultrasonic waves are greatly reflected at the interface between the cover glass 21 and air. Also, when the protective film 30 is attached to the cover glass 21, the ultrasonic reflection is small at the interface between the cover glass 21 and the adhesive 30B and at the interface between the adhesive 30B and the film base material 30A. On the other hand, at the interface between the film base material 30A and air, the ultrasonic reflection is large.

[0029] Therefore, the information processing apparatus 10 forms an interface between the protective film 30 (film base material 30A) and air. That is, the information processing apparatus 10 prompts the user with a message or the like to maintain a state where there is no finger in the detection area (the dotted rectangle in FIG. 4) of the fingerprint sensor 5. Then, the information processing apparatus 10 emits pulsed ultrasonic waves to the fingerprint sensor 5 and then continues to receive the reflected waves for a predetermined time. And the information processing apparatus 10 measures the elapsed time (time) Tx (and time interval) when the power of the reflected wave is the strongest among the continuously received reflected waves. The information processing apparatus 10 can correct the deviation of the appropriate reception window start time due to the change in the ultrasonic wave path caused by the attachment of the protective film 30 by resetting the elapsed time Tx as the start time of the reception window when the protective film 30 is attached, and obtain an appropriate reception window start time. Note that the information processing apparatus 10 may set the section where the power of the reflected wave is equal to or higher than the reference as the width (time interval) of the reception window in the section before and after the elapsed time Tx.

[0030] (Processing) FIG. 6 is a diagram illustrating the reception window correction process executed by the information processing apparatus 10. In this process, the information processing apparatus 10 first determines whether correction is necessary (S1). That is, this process is executed, for example, when the information processing apparatus 10 recognizes that the correction of the reception window should be performed at present. The information processing apparatus 10 can recognize that the correction should be performed, for example, by detecting two holes in the protective film within the detection area of the fingerprint sensor 5 illustrated in FIG. 4. Further, when the pattern formed by a plurality of holes in the protective film within the detection area of the fingerprint sensor 5 changes from before, the information processing apparatus 10 can recognize that the correction should be performed again. Therefore, the process of S1 is an example of determining whether a specific pattern is included in the image detected by the ultrasonic sensor.

[0031] Further, the information processing apparatus 10 OLED When receiving an operation such as pressing a button or selecting a menu displayed on a display such as a 4-inch display from the touch screen sensor 3, the information processing apparatus 10 can recognize that the correction should be performed. For example, when the user attaches the protective film 30 OLED to the screen (cover glass 21) of the 4-inch display (and the touch screen sensor 3), an application program that executes the process of FIG. 6 may be started by pressing a button, selecting a menu, or the like. The determination in S1 is an example of determining whether adjustment of the signal processing method detected by the ultrasonic sensor is necessary.

[0032] If the correction of the reception window should not be performed (NO in S1), the information processing apparatus 10 terminates the process without executing the process. If the correction of the reception window should be performed (YES in S1), the CPU 1 of the information processing apparatus 10 displays guidance to the user not to cover the detection area of the fingerprint sensor with a finger or the like, and prompts attention (S2). The process of S2 can be said to be an example of outputting information for guiding an object including the user's finger not to contact the outer surface of the protective film covering the screen of the display unit in a partial area when adjusting the signal processing method. Note that the CPU 1 may output the guidance from the speaker 13 as voice.

[0033] Next, the CPU 1 causes the fingerprint sensor 5 (transmitter section) to emit ultrasonic pulses (S3). Then, the CPU 1 causes the fingerprint sensor 5 (receiver section) to continuously detect ultrasonic reflected waves for a predetermined time (S4). The information processing apparatus 10 may store the detected reflected waves in the memory 2, for example, in time series.

[0034] In the above processing, the information processing apparatus 10 does not need to individually store all the reception signals of the individual receiver sections formed by the piezoelectric element array of the ultrasonic fingerprint sensor 5. That is, the information processing apparatus 10 may store only some of the signals among the receiver sections included in the piezoelectric element array of the fingerprint sensor 5. Further, the information processing apparatus 10 may integrate or average the reception signals of a plurality of receiver sections included in the piezoelectric element array of the fingerprint sensor 5. In the process of FIG. 6, it is only necessary to correct the reception window according to the change in the ultrasonic propagation path, and it is not necessary to acquire two-dimensional information such as an image.

[0035] Next, the information processing apparatus 10 specifies the peak position of the detection signal from the ultrasonic pulse emission time in S3, that is, the elapsed time Tx from the ultrasonic pulse emission time. Then, the information processing apparatus 10 determines the specified elapsed time as the reception window start time (S5). The process of S5 is an example of determining the time interval for receiving the reflected wave at the time of fingerprint detection from the time change of the reception signal of the reflected wave after the ultrasonic emission time.

[0036] Note that the information processing apparatus 10 may use the value before correction as it is for the width of the reception window. Also, as described above, the information processing apparatus 10 may set, as the width of the reception window, the time interval in the time interval before and after the elapsed time Tx during which the detection signal intensity is close to the peak and equal to or higher than the reference value. The correction of the reception window can be said to be an adjustment of the signal processing method. That is, The processes of S2 to S5 are an example of adjustment of the signal processing method.

[0037] (Effect of the First Embodiment) The information processing apparatus 10 of the present embodiment causes the ultrasonic fingerprint sensor 5 to emit ultrasonic pulses and determines the reception window from the peak of the reflected signal. Therefore, even if a protective film 30 is attached to a display such as 4 (and the touch screen sensor 3), the information processing apparatus 10 can correct it to an appropriate reception window or set the reception window. As a result, the information processing apparatus 10 can suppress a decrease in the image quality of the ultrasonic fingerprint sensor 5 due to the attachment of the protective film 30. OLED Further, the information processing apparatus 10 can detect the presence, change, etc. of the protective film 30 based on a pattern on the protective film 30 within the detection area of the fingerprint sensor 5, such as a hole formed in the protective film 30, and can determine whether correction is necessary. Therefore, as long as the protective film 30 suitable for the processing of the information processing apparatus 10 is used, the information processing apparatus 10 can set an appropriate reception window regardless of the presence or change of the protective film 30.

[0038] In addition, when the information processing apparatus 10 receives, from the touch screen sensor 3, the pressing of a button displayed on a display such as 4, the selection of a menu, etc., it can recognize that it is a situation in which correction should be performed. Therefore, it is possible to provide a tool for adjusting the image quality of the ultrasonic fingerprint sensor 5 to the user who attaches the protective film 30.

[0039] That is, the correction in the present embodiment can be called and executed by a menu operation by the user after the user attaches the protective film 30. At that time, the user is guided not to cover the detection area of the fingerprint sensor 5 with a finger. Further, when registering a fingerprint, the information processing apparatus 10 can also call the correction function first, guide the user to operate the correction function, and execute the correction in a natural form. OLED In other words, the correction in the present embodiment can be called and executed by a menu operation by the user after the user attaches the protective film 30. At that time, the user is guided not to cover the detection area of the fingerprint sensor 5 with a finger. Further, when registering a fingerprint, the information processing apparatus 10 can also call the correction function first, guide the user to operate the correction function, and execute the correction in a natural form.

[0040] That is, the correction in the present embodiment can be called and executed by a menu operation by the user after the user attaches the protective film 30. At that time, the user is guided not to cover the detection area of the fingerprint sensor 5 with a finger. Further, when registering a fingerprint, the information processing apparatus 10 can also call the correction function first, guide the user to operate the correction function, and execute the correction in a natural form.

[0041] Furthermore, when the information processing apparatus 10 executes the process shown in FIG. 6, it displays guidance to prompt the user not to cover the detection area of the fingerprint sensor 5 with a finger or the like, thereby prompting attention. For this reason, the interface between the protective film 30 and the air is maintained, and the reception window start time can be set accurately.

[0042] <Second Embodiment> In the first embodiment described above, the information processing apparatus 10 causes the fingerprint sensor 5 to continuously detect reflected ultrasonic waves for a predetermined time (S4 in FIG. 6). However, the processing of the information processing apparatus 10 is not limited to such processing. For example, the information processing apparatus 10 may cause the fingerprint sensor 5 to intermittently detect reflected ultrasonic waves.

[0043] FIG. 7 is a diagram illustrating the correction process of the reception window by intermittently detecting the reflected ultrasonic waves by the fingerprint sensor 5. The processing and configuration of the information processing apparatus 10 in this embodiment other than intermittently detecting the reflected ultrasonic waves by the fingerprint sensor 5 are the same as those in the first embodiment. Therefore, the configuration of the information processing apparatus 10 described in the first embodiment is also applicable to this embodiment. Also, the process of FIG. 7 is also executed when it is recognized that the reception window should be corrected by the information processing apparatus 10 as in the first embodiment (when YES in S1).

[0044] Also in this process, the CPU 1 of the information processing apparatus 10 displays guidance to prompt the user not to cover the detection area of the fingerprint sensor with a finger or the like, thereby prompting attention (S2). Next, the information processing apparatus 10 causes the CPU 1 to emit ultrasonic pulses to the fingerprint sensor 5 (transmitter unit) and also causes the fingerprint sensor 5 (receiver unit) to detect reflected waves for a predetermined period (Ty to Ty + dt). There is no particular limitation on the pulse width of the ultrasonic wave. There is no particular limitation on the pulse width of the ultrasonic wave.

[0045] Here, Ty is the elapsed time from the point in time when the ultrasonic pulse is emitted. Also, dt is the time interval for detecting the reflection by the fingerprint sensor 5 (receiver unit). It is desirable that dt be a time interval longer than the pulse width emitted by the fingerprint sensor 5 (transmitter unit). The information processing device 10 repeatedly executes such emission of ultrasonic pulses and detection of reflected waves in a predetermined period (Ty to Ty + dt) while changing the time Ty. The information processing device 10 stores in the memory 2 the time Ty after the emission of the ultrasonic pulse and the electrical signal intensity at the fingerprint sensor 5 (receiver unit) due to the reflected wave in the time interval dt. In this way, the information processing device obtains time-series data of the reflected signal intensity at each time Ty after the emission of the ultrasonic pulse (S3A). The process of S3A is an example of repeatedly performing ultrasonic emission and detection of reflected waves intermittently.

[0046] Then, similar to the case of the first embodiment, the information processing device 10 specifies the peak position, that is, the elapsed time from the point in time when the ultrasonic pulse is emitted, from the time-series data detected in S2A. Then, the information processing device 10 determines the specified elapsed time as the reception window start time (S5). Similar to the first embodiment, the information processing device 10 may use the value before correction as it is for the width of the reception window. Also, as described above, the information processing device 10 may set the width of the reception window from the time interval in the time-series data before and after the elapsed time Ty where the detection signal intensity is close to the peak and becomes equal to or greater than the reference value. The processes of S2 to S4 are an example of adjustment of the signal processing method.

[0047] As described above, the information processing device 10 of the present embodiment can correct the reception window with respect to the attachment of the protective film 30 by repeatedly performing intermittent operation, that is, detection of reflected waves in a predetermined period (Ty to Ty + dt) while shifting the time. The process of the present embodiment is effective when the ultrasonic fingerprint sensor 5 cannot continuously detect ultrasonic reflected waves for a predetermined time.

[0048] <Third Embodiment> In the above-described first and second embodiments, the information processing apparatus 10 corrects the reception window by causing the fingerprint sensor 5 to emit ultrasonic pulses and detecting the peak of the reflected signal. However, the correction of the reception window or the determination of the appropriate value by the information processing apparatus 10 is not limited to the above processing.

[0049] For example, the information processing apparatus 10 may recognize the characteristics of the protective film 30 by detecting a specific pattern (for example, a hole) formed in the protective film 30. That is, in the present embodiment, a specific pattern (hole) is provided in the protective film in advance. The information processing apparatus 10 may change the reception window start time ( and the width of the window) according to the specific pattern by the fingerprint sensor 5.

[0050] More specifically, the information processing apparatus 10 may detect the specific pattern by the fingerprint sensor 5 on the detection area of the fingerprint sensor 5 illustrated in FIG. 4. Further, the information processing apparatus 10 includes a reference table in which the pattern corresponds to the set parameters. Then, the information processing apparatus 10 uses the set parameters corresponding to the detected pattern for setting the reception window of the ultrasonic fingerprint sensor 5. At this time, the specific pattern may correspond to physical characteristics such as the thickness and density of the protective film, or may correspond to the reception window start time (and the width of the window). Further, when the same pattern is detected for a certain period or a plurality of times, the information processing apparatus 10 may save an image of this specific pattern and subtract it from the fingerprint image.

[0051] FIG. 8 is a diagram illustrating a cross section of the pattern provided in the protective film 30. As shown in FIG. 8 By providing holes in the protective film 30, an image with holes is generated by the fingerprint sensor 5 based on the difference in the reflected ultrasonic waves between the portion where the protective film 30 exists and the portion where the protective film does not exist. Then, the information processing apparatus 10 recognizes the holes from the image generated by the fingerprint sensor 5, and can recognize that the protective film is adhered on the cover glass 21 through the holes. This process is the same as the detection of a specific pattern for determining whether correction of the reception window is necessary in the first and second embodiments.

[0052] FIG. 9 is an example of a read image by the fingerprint sensor 5 when there is a hole in the protective film 30 at the lower left portion of the detection area (the dotted rectangular area in FIG. 4) of the ultrasonic fingerprint sensor 5. This image is an image in a state where a finger is not in contact with the surface of the protective film on the detection area of the fingerprint sensor 5. The information processing apparatus 10 reads and stores this state image in advance at a certain timing before fingerprint registration, before fingerprint authentication, or otherwise. When actually performing authentication, the information processing apparatus 10 can cancel the holes in the protective film 30 by performing image processing (subtraction processing for each pixel) on the pre-stored image from the image when the finger contacts the detection area, thereby eliminating the influence on fingerprint authentication. Note that the information processing apparatus 10 may perform processing such as smoothing in advance on the pre-stored image to gradually reduce noise and the like, so that no pattern exists except for the portion where the specific pattern (holes) of the protective film 30 is formed.

[0053] FIG. 10 is an example of a specific pattern formed in the protective film 30. The broken line represents the position corresponding to the detection area of the fingerprint sensor 5. The specific pattern (holes) shall have a size that does not affect fingerprint authentication. The specific pattern (holes) is provided at the edge of the detection area of the fingerprint sensor 5 so as not to affect fingerprint authentication. When the specific pattern is a hole, identification information for identifying a plurality of protective films 30 is defined by changing the position where the holes are formed and the number of holes.

[0054] The information processing apparatus 10 recognizes the positions where specific patterns (holes) are formed and the number of holes, and identifies a plurality of protective films 30. Note that the specific patterns (holes) do not penetrate the protective film 30, so an air gap is generated, but the appearance on the surface of the protective film 30 can be made to have no sense of incongruity.

[0055] FIG. 11 is a diagram illustrating a cross-sectional shape of a specific pattern that does not penetrate the protective film 30. That is, a specific pattern that does not penetrate the protective film 30 is formed on the back side of the film base material 30A of the protective film 30. Then, the adhesive 30B is applied to locations other than the location where the specific pattern on the back side of the film base material 30A is formed. Such a protective film 30 has an appearance with no sense of incongruity on the surface of the protective film 30 when it is attached to a display such as the 4-in-1 of the information processing apparatus 10. OLED When attached to a display such as the 4-in-1 of the information processing apparatus 10, the protective film 30 has an appearance with no sense of incongruity on the surface of the protective film 30.

[0056] FIG. 12 is a diagram illustrating the configuration of a reference table that associates the specific patterns stored in the memory 2 of the information processing apparatus 10 with the characteristics of the protective film 30. Each row of this reference table holds information on a different protective film 30. Also, each row of this reference table is identified by a specific pattern. In the example of FIG. 12, each row of this reference table has elements in columns such as pattern, base material material, base material thickness, adhesive thickness, window start time, and window width.

[0057] In the "pattern" column of this reference table, an image of the specific pattern or the address of the storage destination of the image is stored. However, identification information (number, etc.) corresponding to the specific pattern may be set in the pattern column. In any case, it is sufficient that the row of the reference table can be uniquely determined when the information processing apparatus 10 detects a specific pattern.

[0058] The information processing apparatus 10 specifies the corresponding row of the reference table from the specific pattern, and acquires the material of the base material of each protective film 30, the thickness of the base material, and the thickness of the adhesive. Then, the information processing apparatus 10 The start time (and window width) of the reception window may be corrected or determined based on the material of the base material, the thickness of the base material, and the thickness of the adhesive.

[0059] Also, in the example of FIG. 12, the reference table has columns for "reception window start time" and "reception window width". In the column for "reception window start time", the appropriate reception window start time when each protective film 30 is attached is stored. In the column for "reception window width", the appropriate reception window width (time interval) when each protective film 30 is attached is stored. Therefore, the information processing apparatus 10 can directly obtain the appropriate reception window start time and window width from the specific pattern.

[0060] FIG. 13 is a diagram illustrating a process (referred to as a window determination process) for determining the reception window start time based on a specific pattern. Also in this process, the CPU 1 of the information processing apparatus 10 displays guidance to the user so as not to cover the detection area of the fingerprint sensor with a finger or the like, and prompts attention, similar to the first or second embodiment (S11). Next, the CPU 1 acquires an image from the fingerprint sensor 5 and detects a specific pattern (S12). The detection of the specific pattern is determined by whether the image from the fingerprint sensor 5 matches a specific template. The template of the specific pattern is, for example, each pattern in the pattern column of the reference table in FIG. 12. The process of S12 can be said to be an example of determining whether a specific pattern is included in the image detected by the ultrasonic sensor.

[0061] Then, when the CPU 1 detects a specific pattern, it determines the identification information corresponding to the specific pattern, accesses the row corresponding to the identification information from the reference table stored in the memory 2, and determines the reception window start time (S13). The process of S13 can be said to be an example of determining the time interval for receiving the reflected wave at the time of fingerprint detection as the time interval corresponding to the specific pattern.

[0062] Note that the CPU 1 may read the characteristics of the protective film 30 such as the material of the base material, the thickness of the base material, and the thickness of the adhesive from the reference table, and calculate the reception window start time and the like. Further, the CPU 1 may read the corresponding reception window width from the reference table and use it as the corrected reception window width. Therefore, the process of S13 can also be said to be an example of determining the time period for receiving the reflected wave at the time of fingerprint detection based on the characteristics of the protective film that covers the screen of the display unit stored in association with a specific pattern.

[0063] FIG. 14 is a diagram illustrating the fingerprint authentication process of the information processing apparatus 10 according to the present embodiment. In this process, the information processing apparatus 10 acquires an image from the fingerprint sensor 5 (S21). Then, the information processing apparatus 10 subtracts an image including a specific pattern stored in the memory 2 from the image acquired from the fingerprint sensor (S22). Here, the image including the specific pattern is the one acquired from the fingerprint sensor 5 in a state where the finger is not in contact with the detection area of the fingerprint sensor 5, as illustrated in FIG. 9. Further, for the image including the specific pattern, by performing a smoothing process on the image, the image other than the specific pattern may have no pixel value (for example, pixel value 0 in a binary image). The process of S22 can be said to be an example of deleting a specific pattern from the image detected by the ultrasonic sensor. Then, the information processing apparatus 10 recognizes the fingerprint and executes fingerprint authentication (S23).

[0064] (Effect of the Third Embodiment) As described above, the information processing apparatus 10 can suppress a decrease in the resolution of the image by the fingerprint sensor 5 even when the protective film 30 is attached, maintain the biometric authentication accuracy, and further improve it.

[0065] A protective film 30 provided with holes at the ends of the area on the detection area of the fingerprint sensor 5 that has no influence on fingerprint authentication for the information processing apparatus 10 OLEDBy attaching it to a display such as 4, the ultrasonic fingerprint sensor 5 recognizes a specific pattern, that is, the number and position of holes. The protection film 30 has the number and position of holes assigned according to the material, thickness, etc. of the protection film 30. Thereby, the information processing apparatus 10 specifies a row of a table identified by a specific pattern specified by the number and position of holes in the reference table formed in the memory 2. Then, the information processing apparatus 10 acquires characteristics such as the material of the base material of the protection film 30, the thickness, and the thickness of the adhesive from the specified row of the reference table, and applies tuning parameters according to the characteristics. Thereby, the information processing apparatus 10 can improve the resolution of the image read by the fingerprint sensor 5 and also improve the authentication performance in a state where the protection film 30 is attached.

[0066] Note that the information assigned to the number and position of the holes in the protection film is not limited to the material and thickness of the protection film, and other information can also be assigned.

[0067] Also, in the process of this embodiment, even if a specific pattern is formed on the protection film 30, as in the process of FIG. 14, the image of the specific pattern is subtracted from the image to be authenticated before fingerprint authentication. As a result, the information processing apparatus 10 can exclude the influence of the specific pattern formed on the protection film 30 in the fingerprint authentication process.

[0068] <Other modifications> In each of the above embodiments, the information processing apparatus 10 is used as a display OLED It has 4 and a touch screen sensor 3. However, the display of the information processing apparatus 10 is OLED not limited to 4. For example, the information processing apparatus 10 may have a liquid crystal display.

[0069] Also, for example, when the optical characteristics of the camera 15 (see FIG. 3) are changed by the protection film 30, by assigning correction information of the optical characteristics to the number and position of the holes in the protection film, the information processing apparatus 10 can recognize the number and position of the holes with the fingerprint sensor 5 and correct the optical characteristics of the camera 15.

[0070] Also, for example, when the information processing apparatus 10 is a mobile phone used within a company, by assigning departments to the number and position of the holes in the protective film, the information processing apparatus 10 can recognize the department of its owner. Further, when the owner changes departments, the information of the department held by the information processing apparatus 10 can be updated simply by replacing the protective film with the number and position of holes corresponding to the destination department.

[0071] <Computer-readable recording medium> A program that causes a computer or other machine or device (hereinafter referred to as a computer or the like) to realize any of the above functions can be recorded on a computer-readable recording medium. Then, by causing the computer or the like to read and execute the program of this recording medium, the function can be provided.

[0072] Here, a computer-readable recording medium refers to a recording medium that stores information such as data and programs by electrical, magnetic, optical, mechanical, or chemical actions and can be read by a computer or the like. Examples of removable recording media of this type from a computer or the like include flexible disks, magneto-optical disks, CD-ROMs, CD-R / Ws, DVDs, Blu-ray disks, DATs, 8mm tapes, memory cards such as flash memories, etc. Also, examples of recording media fixed to a computer or the like include hard disks, ROMs (read-only memories), etc. Further, an SSD (Solid State Drive) can be used as both a removable recording medium from a computer or the like and a recording medium fixed to a computer or the like.

Explanation of reference numerals

[0073] 1 CPU 2 Memory 3 Touch screen sensor 4 OLED 5 Ultrasonic fingerprint sensor 10 Information processing device 11 Wireless communication unit 12 Receiver 13 Speaker 14 Microphone 15 Camera 21 Cover glass 30 Protective film

Claims

1. A housing, an ultrasonic sensor capable of detecting a fingerprint of a finger that contacts the surface of the housing, and a control unit, wherein the control unit determines whether adjustment of a signal processing method detected by the ultrasonic sensor is necessary, and when it is determined that the adjustment is necessary, the control unit is a control unit that executes adjustment of the signal processing method, determines whether a specific pattern is included in an image detected by the ultrasonic sensor, and an information processing apparatus that, when the specific pattern is included in the image detected by the ultrasonic sensor, determines a time period for receiving a reflected wave during fingerprint detection to be a time period corresponding to the specific pattern.

2. A housing, an ultrasonic sensor capable of detecting a fingerprint of a finger that contacts the surface of the housing, a control unit, and a display unit that guides an operation by a user, wherein the ultrasonic sensor detects a fingerprint of a finger that contacts a partial area of a screen of the display unit, the control unit determines whether adjustment of a signal processing method detected by the ultrasonic sensor is necessary, and when it is determined that the adjustment is necessary, the control unit is a control unit that executes adjustment of the signal processing method, determines whether a specific pattern is included in an image detected by the ultrasonic sensor, and an information processing apparatus that, when the specific pattern is included in the image detected by the ultrasonic sensor, determines a time period for receiving a reflected wave during fingerprint detection based on characteristics of a protective film that covers the screen of the display unit and is associated with the specific pattern.

3. The adjustment of the signal processing method includes causing the ultrasonic sensor to emit ultrasonic waves and detecting a reflected wave of the emitted ultrasonic waves, and determining, from a temporal change of a reception signal of the reflected wave after a time point of emission of the ultrasonic waves, a time period for receiving a reflected wave during fingerprint detection, The information processing apparatus according to claim 1 or 2.

4. The adjustment of the signal processing method includes intermittently repeating emission of ultrasonic waves and detection of reflected waves, the information processing apparatus according to claim 3.

5. When executing adjustment of the signal processing method, the control unit outputs information for guiding an object including a finger of the user not to contact an outer surface of a protective film that covers the screen of the display unit in the partial area. The information processing apparatus according to claim 2.

6. The control unit deletes the specific pattern from an image detected by the ultrasonic sensor and recognizes a fingerprint. The information processing apparatus according to claim 1 or 2.

7. ​ ​ A computer determines whether adjustment of a signal processing method detected by an ultrasonic sensor capable of detecting a fingerprint of a finger is necessary, and when it is determined that the adjustment is necessary, an information processing method for performing the adjustment of the signal processing method, wherein it is determined whether a specific pattern is included in an image detected by the ultrasonic sensor, and when the specific pattern is included in the image detected by the ultrasonic sensor, a time interval for receiving a reflected wave at the time of fingerprint detection is determined to be a time interval corresponding to the specific pattern.

8. A computer determines whether adjustment of a signal processing method detected by an ultrasonic sensor capable of detecting a fingerprint of a finger is necessary, and when it is determined that the adjustment is necessary, an information processing method for performing the adjustment of the signal processing method, wherein a fingerprint of a finger in contact with a partial area of a screen of a display unit is detected by the ultrasonic sensor, it is determined whether a specific pattern is included in an image detected by the ultrasonic sensor, and when the specific pattern is included in the image detected by the ultrasonic sensor, a time interval for receiving a reflected wave at the time of fingerprint detection is determined based on characteristics of a protective film covering the screen of the display unit stored in association with the specific pattern.

9. The adjustment of the signal processing method includes causing the ultrasonic sensor to emit ultrasonic waves and detecting a reflected wave of the emitted ultrasonic waves, and determining a time interval for receiving a reflected wave at the time of fingerprint detection from a time change of a reception signal of the reflected wave after a time point of emission of the ultrasonic waves, and the information processing method according to claim 7 or 8.

10. A program for causing a computer to determine whether adjustment of a signal processing method detected by an ultrasonic sensor capable of detecting a fingerprint of a finger is necessary, and when it is determined that the adjustment is necessary, perform the adjustment of the signal processing method, wherein it is determined whether a specific pattern is included in an image detected by the ultrasonic sensor, and when the specific pattern is included in the image detected by the ultrasonic sensor, cause the time interval for receiving a reflected wave at the time of fingerprint detection to be determined to be a time interval corresponding to the specific pattern.

11. A computer determines whether adjustment of a signal processing method detected by an ultrasonic sensor capable of detecting a fingerprint of a finger is necessary, ​ ​ ​ ​ ​ A program for causing adjustment of a signal processing method when it is determined that such adjustment is necessary, detecting a fingerprint of a finger that touches a partial region of a screen of a display unit by the ultrasonic sensor, determining whether a specific pattern is included in an image detected by the ultrasonic sensor, a program for causing execution of determining a time interval for receiving a reflected wave at the time of fingerprint detection based on characteristics of a protective film covering the screen of the display unit memorized in association with the specific pattern when the specific pattern is included in the image detected by the ultrasonic sensor. [

12. ] The adjustment of the signal processing method includes causing the ultrasonic sensor to emit ultrasonic waves and detecting reflected waves of the emitted ultrasonic waves, and determining a time interval for receiving a reflected wave at the time of fingerprint detection from a temporal change of a reception signal of the reflected waves after a time point of emission of the ultrasonic waves, The program according to claim 10 or 11, including the above.

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