CN116563955A - Living body fingerprint detection device and detection method - Google Patents

Abstract

The invention provides a living fingerprint detection device and a living fingerprint detection method, wherein the living fingerprint detection device comprises a light source and a recognition module, wherein light generated by the light source is emitted to a fingerprint to be detected, the recognition module comprises at least one sensor and an optical component, the optical component is positioned on an optical path of the at least one sensor, reflected light of the fingerprint to be detected reaches the at least one sensor through the optical component, and the at least one sensor carries out living fingerprint judgment based on spectral information of the received reflected light.

Description

Living body fingerprint detection device and detection method

Technical Field

The invention relates to the field of fingerprint detection, in particular to a living fingerprint detection device and a living fingerprint detection method.

Background

Various types of biometric systems are increasingly used to provide greater security and/or enhanced user convenience. For example, fingerprint sensing systems have been widely used in various types of terminal devices, such as smart phones for consumers, due to their small size, high performance, and high user acceptance. At present, various fingerprint sensing systems are circulated in the market, such as a sensing system based on a capacitive fingerprint module, a sensing system based on an optical fingerprint module and the like, and the fingerprint sensing system of the type can realize unlocking, but after being applied to fingerprint identification unlocking of a mobile terminal, lawless persons can crack a security system of a user by stealing the fingerprint of the user to prepare a fake fingerprint, so that the probability of the fingerprint password of the mobile terminal being recognized is increased, and the security of information of the mobile terminal is threatened greatly.

However, the existing living fingerprint identification schemes have certain drawbacks, such as the capacitor module has the disadvantages of poor environmental stability, short service life and insufficient living detection capability, and the optical module generally does not have the living detection capability, so that a simple and reliable fingerprint identification scheme is needed to realize living fingerprint identification.

Disclosure of Invention

It is a principal advantage of the present invention to provide a living fingerprint detection device and a detection method, wherein the living fingerprint detection device is adapted for living detection, improving the applicability of the fingerprint detection device.

Another advantage of the present invention is to provide a living fingerprint detection apparatus and a detection method, wherein the living fingerprint detection apparatus performs living judgment based on spectral information after percutaneous reflection, thereby realizing living detection of fingerprints and improving detection accuracy.

Another advantage of the present invention is to provide a living fingerprint detection apparatus and a detection method, wherein the living fingerprint detection apparatus determines a recognition result of the object to be recognized based on a comparison result of reference spectral response data and recognition spectral response data, which is beneficial to improving accuracy of fingerprint detection recognition.

Another advantage of the present invention is to provide a living fingerprint detection apparatus and a living fingerprint detection method, wherein the living fingerprint detection apparatus includes a light source and an identification module, wherein the light source is disposed at or adjacent to the identification module, and is used by the light source to illuminate a fingerprint to be detected.

Another advantage of the present invention is to provide a living fingerprint detection device and a detection method, wherein the light source is disposed on a circuit board or a frame of the identification module, which is beneficial to miniaturization of the living fingerprint detection device.

The invention further provides a living fingerprint detection device and a detection method, wherein the living fingerprint detection device obtains original data, namely light intensity information, respectively carries out image information correction and spectrum information correction on the original data, then respectively adopts a fingerprint identification algorithm and a living algorithm, compares fingerprint images and spectrum information with corresponding information extracted during input to obtain matching degree, and when the matching degree of the fingerprint images and the spectrum information is higher than a threshold value, input verification passes, otherwise output verification fails.

Another advantage of the present invention is to provide a living fingerprint detection apparatus and a living fingerprint detection method, wherein the living fingerprint detection method includes image information correction and spectrum information correction including image processing method of surrounding mean value compensation (binning), and accuracy of data detection is improved by weighted average.

Another advantage of the present invention is to provide a living fingerprint detection apparatus and a living fingerprint detection method, wherein the living fingerprint detection method further includes a living algorithm process, wherein the effective corrected spectral parameters (or spectral information) extracted from the processed raw data (light intensity information) and the corresponding parameters of the input data form a data set, and a correlation coefficient R after straight line fitting is calculated, and when the correlation coefficient R is greater than a corresponding threshold, it is determined that the living fingerprint is a living fingerprint, otherwise, it is determined that the living fingerprint is not a living fingerprint.

In accordance with one aspect of the present invention, a living fingerprint detection device of the present invention capable of achieving the foregoing and other objects and advantages includes:

the light source emits light generated by the light source to the fingerprint to be detected; and

the identification module comprises at least one sensor and an optical component, wherein the optical component is positioned on an optical path of the at least one sensor, reflected light of the fingerprint to be detected reaches the at least one sensor through the optical component, and the at least one sensor performs living fingerprint judgment based on the received spectral information of the reflected light.

According to one embodiment of the present invention, the identification module further includes a bracket and a circuit board, wherein the sensor is electrically connected to the circuit board, the bracket is disposed on the circuit board, the optical component is disposed on the bracket, the optical component is supported by the bracket, and the optical component is held in a photosensitive path of the sensor.

According to one embodiment of the invention, the light source is arranged on the circuit board and is communicated with the sensor through the circuit board.

According to one embodiment of the invention, the identification module further comprises a transparent cover plate and a support member, wherein the transparent cover plate is supported by the support member on the photosensitive path of the sensor.

According to one embodiment of the present invention, the circuit board further includes a first circuit board and a second circuit board, wherein the sensor is disposed on the first circuit board, and the light source is disposed on the second circuit board.

According to one embodiment of the invention, the wiring board further comprises at least one connection line, wherein the connection line electrically connects the first wiring board and the second wiring board.

According to an embodiment of the present invention, the wiring board further includes a flexible board, wherein the flexible board is disposed at the first wiring board and the second wiring board, and the first wiring board and the second wiring board are electrically connected through the flexible board.

According to one embodiment of the invention, the sensor is a spectroscopic sensor.

According to an embodiment of the invention, the identification module comprises a spectrum sensor, an imaging sensor and a light splitting element, wherein the light splitting element is located on an optical path of the spectrum sensor and the imaging sensor, the detection light is split into a first detection light and a second detection light by the light splitting element, the first detection light reaches the spectrum sensor after being turned by the light splitting element, the second detection light reaches the imaging sensor after being transmitted by the light splitting element, the spectrum sensor obtains spectrum information of an object to be detected through the first detection light, and the imaging sensor obtains image information of the object to be detected through detecting the second detection light.

According to one embodiment of the present invention, the identification module further includes a light homogenizing member, wherein the light homogenizing member is disposed between the light splitting member and the spectrum sensor, and the light homogenizing member homogenizes the light, and the spectrum sensor obtains the spectrum information to perform the living body discrimination.

According to one embodiment of the present invention, the identification module further includes a lens group, and the lens group is located between the imaging sensor and the light splitting element, and the lens group is received by the imaging chip after adjusting the light.

According to an embodiment of the present invention, the imaging sensor and the lens group are disposed in a horizontal direction, wherein the spectral sensor and the light homogenizing sheet are disposed in a height direction.

According to another aspect of the present invention, there is further provided a living body fingerprint detection method including:

(a) Acquiring light intensity information acquired by fingerprints;

(b) Acquiring fingerprint images and spectrum information based on the acquired light intensity information; and

(c) And comparing the fingerprint image and the spectrum information with the input reference information, and when the matching degree is higher than a threshold value, inputting verification, otherwise, outputting verification failure.

According to one embodiment of the invention, the detection method further comprises: and correcting the light intensity information, wherein the light intensity information correction comprises an image processing mode of surrounding average value compensation.

According to one embodiment of the invention, in the image information correction, the intensity values of the spectral pixels are replaced by intensity values that are weighted averages of intensities of nearby ordinary physical pixels, thereby generating corrected picture parameters for obtaining a fingerprint image.

According to one embodiment of the invention, the detection method further comprises: and correcting the spectrum information corresponding to the spectrum pixel, dividing or subtracting the intensity value of the current spectrum pixel by the weighted average intensity value of the adjacent common pixels to obtain the relative intensity, and taking the relative intensity as corrected spectrum information to carry out subsequent processing.

According to one embodiment of the invention, the detection method further comprises: calculating a correlation coefficient R formed by the effective correction spectrum information extracted from the processed original data and the recorded reference spectrum information, and judging as a living body when the correlation coefficient R is larger than a corresponding threshold value; otherwise, the non-living body is judged.

According to one embodiment of the invention, the detection method further comprises the steps of:

under the condition of n times of effective recording, carrying out correlation coefficient R calculation on each spectrum characteristic parameter and other n-1 times, taking the lowest correlation coefficient R_min, carrying out specific formula calculation on the lowest correlation coefficient R_min and a system setting parameter k to obtain a judging threshold value R_t of the recording comparison, and when n-1 or more than n are larger than the corresponding judging threshold value, considering the test as a living body, otherwise, judging as a non-living body, wherein the specific formula is as follows: r_t=max (r_min, k).

According to one embodiment of the present invention, the detection method further includes the step of consistency determination of the spectral features:

and when the input data is input each time, processing the input spectrum information according to a comparison flow, calculating the correlation coefficient of the input data and the input spectrum information, and if the correlation coefficient is smaller than a system set value m, failing the input.

According to one embodiment of the invention, the detection method further comprises the step of entering a data update:

after each time of judging and detecting success, carrying out correlation coefficient calculation on the spectrum information judged at the time and n pieces of input data, obtaining a corresponding mean value R_atest, comparing the average value R_a1-n with the correlation coefficient mean value R_a1-n between the n pieces of input data, and if R_atest is greater than 1 or more of R_a1-n, replacing the smallest data in R_a1-n in the input data with the data tested at the time.

Further objects and advantages of the present invention will become fully apparent from the following description and the accompanying drawings.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description and accompanying drawings.

Drawings

Fig. 1 is a schematic diagram of a living fingerprint detection device according to a first preferred embodiment of the present invention.

Fig. 2 is a schematic frame view of the living body fingerprint detection device according to the first preferred embodiment of the present invention.

Fig. 3 is a schematic view showing a partial structure of the living body fingerprint detection device according to the first preferred embodiment of the present invention.

Fig. 4 is a schematic view showing the overall structure of the living body fingerprint detection device according to the first preferred embodiment of the present invention.

Fig. 5A to 5C are schematic views of alternative implementations of the overall structure of the living body fingerprint detection device according to the first preferred embodiment of the present invention.

Fig. 6A to 6D are schematic views of alternative implementations of the overall structure of the living body fingerprint detection device according to the first preferred embodiment of the present invention.

Fig. 7 is a schematic structural frame diagram of a sensor of the living body fingerprint detection device according to the first preferred embodiment of the present invention.

Fig. 8A and 8B are schematic views of a microstructure of a sensor of the living fingerprint detection device according to the first preferred embodiment of the present invention.

Fig. 9 is a schematic frame structure of a spectrum sensor of the living body fingerprint detection device according to the first preferred embodiment of the present invention.

Fig. 10 is a sectional view of a spectrum sensor of the living body fingerprint detection device according to the above first preferred embodiment of the present invention.

Fig. 11 is a physical pixel diagram of a spectrum sensor of the living body fingerprint detection device according to the first preferred embodiment of the present invention.

Fig. 12 is a schematic frame diagram of a living fingerprint detection device according to a second preferred embodiment of the present invention.

Fig. 13 is a flowchart of a living fingerprint detection method according to another preferred embodiment of the present invention.

Fig. 14 is a schematic diagram showing a correlation coefficient after linear fitting according to a living fingerprint detection method according to another preferred embodiment of the present invention.

Fig. 15 is a schematic diagram of a living fingerprint detection method according to another preferred embodiment of the present invention.

Detailed Description

The following description is presented to enable one of ordinary skill in the art to make and use the invention. The preferred embodiments in the following description are by way of example only and other obvious variations will occur to those skilled in the art. The basic principles of the invention defined in the following description may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.

It will be appreciated by those skilled in the art that in the present disclosure, the terms "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," etc. refer to an orientation or positional relationship based on that shown in the drawings, which is merely for convenience of description and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore the above terms should not be construed as limiting the present invention.

It will be understood that the terms "a" and "an" should be interpreted as referring to "at least one" or "one or more," i.e., in one embodiment, the number of elements may be one, while in another embodiment, the number of elements may be plural, and the term "a" should not be interpreted as limiting the number.

Overview of detection principle of living fingerprint detection device in the present invention

As shown in fig. 1, due to physiological characteristics such as capillaries (blood) and sweat pores in human skin, the human skin is difficult to forge as compared with fingerprint lines, and due to the physiological characteristics, the skin has different spectral absorption/reflection degrees of different wave bands, which means that living body judgment can be performed according to spectral information reflected by the skin, so that living body detection of fingerprints is realized. Specifically, as shown by the reflection spectrum test on the real finger and the finger model material, the difference between the reflection spectrum of the real finger and the reflection spectrum of the finger model material is huge at the wavelength of 300nm-1100nm, and as shown in fig. 1, the difference between the reflection spectrum data corresponding to the real finger and the reflection spectrum data corresponding to the finger model material is large by taking the test of silica gel, paper, human skin and the like as an example. Therefore, it is possible to make a living body judgment by the received reflection spectrum.

A living body fingerprint detection device and detection method according to the present invention is explained in the following description with reference to fig. 1 to 15 of the drawings of the present specification. The living fingerprint detection device comprises a light source 10 and an identification module 20, wherein the light source 10 emits illumination light to a finger to be detected, and the identification module 20 detects the fingerprint to be detected by detecting the light reflected by the finger. The identification module 20 comprises an optical component 21 and at least one sensor 22, wherein the optical component 21 is located in the optical path of the sensor 22. It is worth mentioning that in this preferred embodiment of the invention, the sensor 22 is an image sensor or a spectral sensor. Preferably, the optical component 21 is a lens group, and the optical component 21 further includes at least one lens. More preferably, the optical assembly 21 is configured to transmit imaging information of a finger print to the sensor 22, wherein the FOV of the optical assembly 21 is between 80 degrees and 130 degrees, the back focal length is between 0.3mm and 5mm, and the total optical length is between 1mm and 10 mm.

The light source 10 is used for illuminating the finger to be detected, and a certain frequency spectrum width (> 30 nm) is needed to be selected. Wherein, the light source can emit monochromatic light or mixed light according to the requirement.

It should be noted that, in the preferred embodiment of the present invention, the light source 10 is disposed on the recognition module 20 or the light source 10 is disposed adjacent to the recognition module 20, the light emitted by the light source 10 reaches the finger to be detected, the detection light reflected by the finger to be detected passes through the optical component 21 of the recognition module 20 to the sensor 22, and then the sensor 22 performs the living body judgment, so as to implement the living body detection of the fingerprint.

In the preferred embodiment of the invention, as shown in fig. 3, the identification module 20 further comprises a bracket 23 and a circuit board 24, wherein the sensor 22 is electrically connected to the circuit board 24. Preferably, the holder 23 is provided to the circuit board 24, the optical assembly 21 is provided to the holder 23, the optical assembly 21 is supported by the holder 23, and the optical assembly 21 is held in a photosensitive path of the sensor 22. It should be noted that the circuit board 24 may be, but is not limited to, a Flexible Printed Circuit (FPC), a rigid Printed Circuit (PCB) or a flexible-rigid printed circuit (F-PCB), a ceramic substrate, etc. The circuit board 24 may be used for driving, controlling, data processing and outputting of the light source and the sensor.

In at least one embodiment of the present invention, since the living fingerprint detection device needs to be miniaturized, the light source 10 may be integrated with the circuit board 24, as shown in fig. 4, or integrated with the stand 23. That is, the light source 10 is fixed to the wiring board 24, or the light source 10 is fixed to the bracket 23. Preferably, the light emitting path of the light source 10 is not parallel to the light sensing path of the sensor 22.

Fig. 5A and 5B show a specific embodiment of the identification module 20 according to the present invention, in the preferred embodiment of the present invention, the identification module 20 further comprises a transparent cover plate 25 and a supporting member 26, wherein the transparent cover plate 25 is supported by the supporting member 26 on the photosensitive path of the sensor 22. The transparent cover 25 is used for placing an object to be measured, such as a finger, and obtains reflected light information of the object to be measured through the transparent cover 25. As an example, the light emitted by the light source 10 is transmitted through the finger print illuminated by the transparent cover plate 25, and the reflected light is reflected by the transparent cover plate 25 into the sensor 22.

It should be noted that, in the preferred embodiment of the present invention, the identification module 20 has a double-bracket structure, wherein the support member 26 supports the transparent cover plate 25, and the support member 26 and the transparent cover plate 25 enclose the bracket 23 and the optical assembly 21 fixed by the bracket 23 inside. The support 26 is an outer support structure, and the support 23 is an inner support structure fixed inside the support 26.

Preferably, the supporting member 26 is disposed on the circuit board 24, wherein the transparent cover plate 25 is fixed to an upper end of the supporting member 26, the other end of the supporting member 26 is fixed to the circuit board 24, and the supporting member 26, the circuit board 24, and the transparent cover plate 25 form a closed space, thereby preventing dust from entering. Preferably, in the preferred embodiment of the present invention, the transparent cover plate 25 is supported by the support 26, and the transparent cover plate 25 is spaced apart from the wiring board 24 by a distance of less than 7mm. In a separate embodiment of the invention, the support 26 and the support 23 are integral, i.e. they are integrated as a unitary structure for fixing and supporting the optical assembly 21 and the transparent cover plate 25.

The light source 10 is provided on the wiring board 24 and is electrically connected to the wiring board 24. Preferably, in the preferred embodiment of the present invention, the light source 10 is located at the inner side of the support 26, wherein the light source 10 is adjacently disposed at the outer side of the bracket 23, and the light emitting path of the light source 10 is not parallel to the light sensing path of the sensor. Alternatively, in other alternative embodiments of the present invention, the light source 10 is disposed on the bracket 23, and the light source 10 is electrically connected to the wiring board 24.

As shown in fig. 5B, according to another aspect of the present invention, the present invention further provides an alternative embodiment of the identification module, wherein the circuit board 24 further includes a first circuit board 241 and a second circuit board 242, wherein the sensor 241 is disposed on the first circuit board 241, and the light source 10 is disposed on the second circuit board 242. The bracket 23 is fixed to the first circuit board 241, and the optical assembly 21 is fixed to the bracket 23 and positioned in the photosensitive path of the sensor 22.

The circuit board 24 further includes a flexible board 244, wherein the flexible board 244 is disposed on the first circuit board 241 and the second circuit board 242, and the first circuit board 241 and the second circuit board 242 are electrically connected through the flexible board 244 to realize the conduction of the circuit board 24.

In an alternative embodiment of the present invention, as shown in fig. 5C, the identification module 20 further includes at least one light homogenizing member 28, wherein the light homogenizing member 28 is disposed on the photosensitive path of the light source 10 for homogenizing the light emitted by the light source. The light homogenizing member 28 is disposed at the emitting end of the light source 10, wherein the light emitted by the light source 10 irradiates the transparent cover plate 25 through the light homogenizing member 28.

An identification module 20 according to another preferred embodiment of the present invention is illustrated in fig. 6A-6C of the drawings of the present invention. The difference from the above preferred embodiment is that in this preferred embodiment of the invention, the transparent cover plate 25 of the identification module is provided to the bracket 23. The stand 23 includes a stand body 231, a lens supporting portion 232, and a cover supporting portion 233, wherein the lens supporting portion 232 is located at an upper end of the cover supporting portion 233. That is, the transparent cover plate 25 is supported above the optical assembly 21 by the bracket 23. The lens supporting part 232 extends inward from the lens body 231 and forms a supporting structure having a light passing hole inside the bracket 23, wherein the cover supporting part 233 extends upward integrally from the bracket body 231 to fix and support the transparent cover 25. Briefly, in the preferred embodiment of the present invention, the support 23 is a two-layered support structure in which the transparent cover plate 25 is supported above the optical assembly 21 by the cover plate supporting portion 233 of the support 23, and the optical assembly 21 is supported below the transparent cover plate 25 by the lens supporting portion 232 of the support 23.

The lens supporting part 232 of the holder 23 divides the inner space of the holder 23 into an upper receiving space 234 and a lower receiving space 235, wherein the optical assembly 21 is held in the upper receiving space 234 of the holder 23, and the sensor 22 is held in the lower receiving space 235 of the holder 23. The light source 10 and the sensor 22 are provided on the wiring board 24 and electrically connected to the wiring board 24. The circuit board 24 further includes a first circuit board 241 and a second circuit board 242, wherein the sensor 241 is disposed on the first circuit board 241, and the light source 10 is disposed on the second circuit board 242. The bracket 23 is fixed to the first circuit board 241, and the optical assembly 21 is fixed to the bracket 23 and positioned in the photosensitive path of the sensor 22.

As shown in fig. 6A, unlike the above preferred embodiment, the light source 10 is disposed at the lens support 232 of the holder 23, wherein the light source 10 is located above the sensor 22. Preferably, the light source 10 is disposed at the holder lens part 232 of the holder 23, and the light emitting path of the light source is not parallel to the light sensing path of the sensor.

Preferably, in the preferred embodiment of the present invention, the first wiring board 241 and the second wiring board 242 are electrically connected; the transparent cover 25 is disposed at the upper end of the bracket 23 and is held on the photosensitive path of the sensor 22. The sensor 22, the holder 23 and the optical assembly 22 supported by the holder 23 form a substantially sealed space; the transparent cover plate 25, the holder 23 and the optical assembly 21 form a substantially sealed space.

As shown in fig. 6B, the identification module 20 of the living fingerprint detection device of the present invention is further provided with at least one heat dissipation hole 201, wherein the at least one heat dissipation hole 201 communicates with the internal space of the identification module to the external environment, and the internal temperature of the identification module 20 is reduced through the heat dissipation hole. As an example, the bracket 23 is provided with an opening, or when the transparent cover 25 is fixed, the transparent cover 25 and the supporting member 26 form the heat dissipation hole 201 at the connection position of the transparent cover 25 and the supporting member 26 by three-sided painting, so that the upper space is not completely closed, and a gap exists for ventilation and heat dissipation.

As shown in fig. 6C, according to another aspect of the present invention, the first circuit board 241 and the second circuit board 242 are electrically connected. The first circuit board 241 and the second circuit board 242 are conducted through pins. Specifically, the wiring board 24 further includes at least one connection line 243, wherein the connection line 243 electrically connects the first wiring board 241 and the second wiring board 242. It is understood that the connection line may be, but not limited to, a metal pin, wherein one end of the connection line 243 is connected to the second circuit board 242, and the other end of the connection line 243 is connected to the first circuit board 241, so as to achieve the conduction between the first circuit board and the second circuit board.

Since the bracket 23, the optical assembly 21 and the first circuit board 241 form a closed space, it is difficult to fix the connection wire 243 to the first circuit board 241 in a conductive manner from a process point of view. Preferably, the bracket 23 is provided with corresponding communication holes 230, wherein the communication holes 230 of the bracket 23 are opposite to the connection position of the first circuit board 241, so that the connection wire 243 can be connected with the first circuit board 241 through the communication holes 230 of the bracket 23 when the second circuit board 242 is disposed on the bracket 23, and then the connection wire 243 is fixed to the first circuit board 241 through welding, gluing, or the like. Further, since the bracket 23 is fixed to the first wiring board 241, the connection wire 243 is connected to the first wiring board 241. Therefore, preferably, the first circuit board 241 has a connection through hole through which the connection wire 243 at least partially passes, so that the connection wire 243 can be fixed to and conducted with the first circuit board 241 from the back surface of the first circuit board 241.

In an alternative embodiment of the present invention, as shown in fig. 6D, the identification module 20 further includes at least one light homogenizing member 28, wherein the light homogenizing member 28 is located in the light sensing path of the light source 10 for homogenizing the light emitted by the light source. The light homogenizing member 28 is disposed at the emitting end of the light source 10, wherein the light emitted by the light source 10 irradiates the transparent cover plate 25 through the light homogenizing member 28.

Preferably, for the solution that the light source is disposed on the first circuit board, the living fingerprint detection device further includes a heat dissipation member, and the heat dissipation member is disposed below the light source, so as to rapidly conduct out heat generated by the light source.

As shown in fig. 6 to 11, the sensor 22 is a spectrum sensor, and the spectrum sensor includes a filtering structure and an image sensor, where the filtering structure is located on a photosensitive path of the image sensor, and the filtering structure is a broadband filtering structure in a frequency domain or a wavelength domain. The passband spectra of different wavelengths of the filter structure are not identical. The filter structure may be a structure or a material having a filter property such as a super surface, a photonic crystal, a nano-pillar, a multilayer film, a dye, a quantum dot, a MEMS (micro electro mechanical system), an FP etalon, a cavity layer, a waveguiding layer, a diffraction element, or the like. For example, in the embodiment of the present application, the optical filtering structure may be a light modulation layer in chinese patent CN 201921223201.2. The image sensor may be a CMOS Image Sensor (CIS), CCD, array photodetector, or the like. The spectroscopic device further includes a data processing unit, which may be a processing unit such as MCU, CPU, GPU, FPGA, NPU, ASIC, that can export data generated by the image sensor to the outside for processing.

The spectrum sensor is used for acquiring finger grain image information and finger spectrum characteristic information so as to realize the verification of finger biological characteristics. The chip size range is between 1/9 'and 1/1.6', the imaging spatial resolution is more than 5 ten thousand pixels, and the spectrum discrimination capability of the light to be detected is equivalent to the spectrum resolution below 30 nm. The spectrum sensor can be attached to the circuit board by adopting a COB or CSP packaging and FC packaging process.

Specifically, the working principle of the spectrum sensor is that the intensity signals of incident light under different wavelengths lambda are marked as f (lambda), the transmission spectrum curve of the optical filtering structure is marked as T (lambda), the spectrum sensor is provided with m groups of optical filtering structures, each group of transmission spectrums are different from each other, and the spectrum sensor is also called as a 'structural unit', and the whole spectrum sensor can be marked as Ti (lambda) (i=1, 2,3, …, m). And corresponding physical pixels are arranged below each group of filter structures, and the light intensity information Ii modulated by the filter structures is detected. In the specific embodiment of the present application, the description is given taking the case that one physical pixel corresponds to one group of structural units as an example, but the present invention is not limited thereto, and in other embodiments, a plurality of physical pixels may be formed as a group corresponding to one group of structural units.

The relationship between the spectral distribution of the incident light and the measured value of the image sensor can be expressed by the following equation:

Ii＝Σ(f(λ)·Ti(λ)·R(λ))

Where R (λ) is the response of the image sensor, noted as:

Si(λ)＝Ti(λ)·R(λ)

the above equation can be extended to a matrix form:

where Ii (i=1, 2,3, …, m) is the response of the image sensor after the light to be measured passes through the broadband filter structure, and corresponds to the light intensity information of the m image sensors, which is also called m "physical pixels", and is a vector with a length of m. S is the optical response of the system for different wavelengths, and is determined by two factors, namely the transmissivity of the filtering structure and the quantum efficiency of the response of the image sensor. S is a matrix, each row vector corresponds to the response of a structural unit to incident light with different wavelengths, wherein the incident light is discretely and uniformly sampled, and n sampling points are all used. The number of columns of S is the same as the number of samples of the incident light. Here, f (λ) is the intensity of the incident light at different wavelengths λ, i.e. the spectrum of the incident light to be measured.

In practical applications, the response parameter S of the system is known, and the spectrum f (can be understood as spectrum recovery) of the input light can be obtained by using algorithm to back-calculate through the light intensity reading I of the image sensor, and the process can adopt different data processing modes according to the situation, including but not limited to: least squares, pseudo-inverses, equalizations, least squares, artificial neural networks, etc.

Taking one physical pixel corresponding to one group of structural units as an example, how to recover one spectrum information, which is also called as a "spectrum pixel", by using m groups of physical pixels (i.e., pixel points on an image sensor) and m groups of corresponding structural units (the same structure on a modulation layer is defined as a structural unit) are described above. It should be noted that in the embodiment of the present application, a plurality of physical pixels may correspond to a set of structural units. It may be further defined that a group of structural elements and corresponding at least one physical pixel constitute a unit pixel, in principle at least one unit pixel constitutes one of said spectral pixels.

On the basis of the implementation mode, the spectral pixels are subjected to array processing, so that the snapshot type spectral imaging device can be realized.

For example, as shown in fig. 8A and 8B, with an image sensor of 1896×1200 pixels (fig. 8A shows a partial area of the image sensor), and selecting m=4, i.e. selecting 4*4 unit pixels to form one spectrum pixel, 474×300 spectrum pixels independent from each other can be implemented, where each spectrum pixel can separately calculate a spectrum result by the above method. After the image sensor is matched with components such as a lens group, the object to be detected can be subjected to snapshot spectrum imaging, so that spectrum information of each point of the object to be detected can be obtained through single exposure.

On the basis, the selection mode of the optical pixels can be rearranged according to actual needs under the condition that the image sensor does not need to be adjusted, so that the spatial resolution is improved. As shown in fig. 8B, the close-packed arrangement of the solid line boxes and the dashed line boxes may be selected to increase the spatial resolution from 474×300 to approximately 1896×1200 in the above example.

Further, for the same image sensor, rearrangement of spatial resolution and spectral resolution can be performed as needed. For example, in the above example, when the spectral resolution requirement is high, 8×8 unit pixels may be used to form one spectral pixel; when the spatial resolution requirement is high, 3*3 physical pixels can be used to form one spectral pixel.

That is, the spectral sensor may acquire light intensity information, which may be used for imaging or for spectral recovery. For example, in the living body fingerprint detection device, the light intensity information may include image information for fingerprint line image restoration and spectrum information for judging a living body.

In an embodiment of the present invention, preferably, the spectrum sensor has a modulation area and a non-modulation area, the modulation area refers to that a filtering structure is disposed on an optical path of the image sensor, and the non-modulation area is correspondingly not provided with the filtering structure, that is, incident light is modulated by the filtering structure in the modulation area and then received by the image sensor. Whereas the non-modulated areas are not modulated, for example when the image sensor is a CMOS chip, the non-modulated areas are implemented directly as black and white pixels (i.e. no bayer array is provided on the CMOS chip). Preferably, the modulation region is mainly used for acquiring spectrum information, and the non-modulation region acquires image information. In individual embodiments, the non-modulated regions may also be implemented as bayer arrays, microlens arrays, convex lenses, concave lenses, fresnel lenses, etc. to modulate the incident light.

Preferably, in this preferred embodiment of the present invention, the area of the modulation region is 10% -50%, preferably 12% -25% of the area of the active area of the spectrum chip, and optionally at least a part of the modulation region and the non-modulation region are spaced apart; therefore, in the process of processing and analyzing, the image information of the non-modulation area around the modulation area can be used for being combined with the spectrum information of the modulation area, and the spectrum information is optimized by utilizing the image information, for example, the image information can be used for removing background noise and the like, so that the spectrum information is more accurate; specifically, the image information of the peripheral non-modulation region may be averaged, and then the value of the modulation region may be divided by or subtracted from the average value of the image information of the peripheral non-modulation region of the modulation region; the spectrum information can be used for assisting the image information to restore the image, generally, the spectrum information has more information, and meanwhile, as the modulation area is provided with a structural unit which is different from the non-modulation area information, the area has information gaps during imaging, so that the spectrum information acquired by the modulation area can be used for calculating to compensate the image information of the area or correct the image information of the adjacent area. For example, as shown in fig. 11, taking the example that the filtering structure corresponds to one physical pixel, two adjacent filtering structures are separated by two physical pixels; i.e. 1 physical pixel with a structural unit is surrounded by 8 physical pixels.

In at least one embodiment of the present invention, since the image information used for calculation may be missing in the modulation area, the image information value of the modulation area may also be calculated by using the image information values obtained by the physical pixels of the peripheral non-modulation area, specifically, the average value of the image information of the peripheral physical pixels may be used as the image information value of the modulation area, so that the whole image is more complete, for example, 8 physical pixels of the following figure surround the physical pixels corresponding to 1 structural unit, and the image information value of the middle modulation area may be calculated by using the peripheral 8 physical pixels; the average value of 24 peripheral physical pixels can be used to calculate the image information value corresponding to the intermediate modulation region.

It should be noted that, in the present embodiment, the spectrum information does not necessarily need to restore the spectrum curve to perform the living body judgment, but may directly perform the living body judgment according to the response. Specifically, acquiring reference spectral response data of an image sensor of the spectrum-based analysis device to a reference object; acquiring identification spectrum response data of an object to be identified by the image sensor of the spectrum-based analysis device; and determining a recognition result of the object to be recognized based on a comparison result of the reference spectral response data and the recognition spectral response data.

Referring to fig. 12 of the drawings, a living body fingerprint detection device according to another aspect of the present invention is illustrated in the following description. The identification module 20 of the living fingerprint detection device includes a spectrum sensor 221A, an imaging sensor 222A, and a spectroscopic element 27A, wherein the spectroscopic element 30 is located in an optical path of the spectrum sensor 221A and the imaging sensor 222A, that is, incident light enters the spectroscopic element 27A. The detection light is split into a first detection light and a second detection light by the light splitting element 27A, wherein the first detection light reaches the spectrum sensor 221A after being turned by the light splitting element 27A, and the second detection light reaches the imaging sensor 222A after being transmitted by the light splitting element 27A. The spectrum sensor 221A obtains spectrum information of the object to be measured by the first detection light, and the imaging sensor 222A obtains image information of the object to be measured by detecting the second detection light.

Preferably, the identification module 20 further includes a light homogenizing member 28A, wherein the light homogenizing member 28A is disposed between the light splitting member 27A and the spectrum sensor 221A, and the light is homogenized by the light homogenizing member 28A, and then the spectrum information is obtained by the spectrum sensor 221A to perform the living body discrimination. It should be noted that, because the surface to be measured is often uneven, such as the fingerprint has valleys and ridges, the spectral response generated by different regions may be different due to the variation of the corresponding regions during the test, so that the difficulty of judging the living body increases. Therefore, even if the area is changed during the test after the light is homogenized by using the light homogenizing member 28A, the spectrum information of the whole area is unchanged.

For example, in the fingerprint living body judging process, a tester deflects at a certain angle when placing a finger, the fingerprint valley and ridge corresponding to the spectrum sensor also change, so that the spectrum information reaching the spectrum sensor changes, at the moment, additional processing is needed to realize accurate judgment, and after light homogenization, the whole valley and ridge are unchanged due to the fact that a light source is not moved, the deflection does not cause the spectrum information to change greatly, and therefore living body judgment can be realized relatively simply and efficiently. Preferably, the identification module 20 of the living fingerprint detection device further includes a lens group 29A, and the lens group 29A is located between the imaging sensor 222A and the spectroscopic element 27A, so that the light is received by the imaging chip after being adjusted, which is beneficial to improving the imaging quality, for example, more clearly.

In view of the size requirements in practical applications, for example, in mobile phones, wearable devices, etc., it is necessary to limit the size in a certain direction. For example, in the height direction, since the imaging sensor 222A is matched with the lens assembly 29A, the focal length is generally required, and the size of the lens assembly is generally larger. Preferably, the imaging sensor 222A and the lens group 29A are disposed in a horizontal direction, wherein the spectral sensor 221A is disposed in a height direction (vertical direction) along with the light homogenizing sheet 28A. That is, after the incident light enters the spectroscopic element 27A in the height direction, the transmission portion enters the light uniformizing member 28A, and reaches the spectrum sensor 221A after being homogenized; the turning portion enters the lens group 29A in the horizontal direction and is adjusted, and is received by the imaging sensor 222A.

It should be noted that, because the identification module of the preferred embodiment of the present invention adopts the spectrum sensor, spectrum information can be obtained, and the spectrum information can be used to determine whether the object to be detected is a living body, so that the security performance of fingerprint identification is higher.

Referring to fig. 13, the present invention further provides a living fingerprint detection method based on the living fingerprint detection device, wherein the spectrum sensor 221A obtains raw data, namely light intensity information, the light intensity information includes image information and spectrum information, and image information correction and spectrum information correction are respectively performed on the raw data; then, respectively adopting a fingerprint identification algorithm and a living body algorithm, and comparing the fingerprint image with spectrum information with corresponding reference information extracted during input to obtain a matching degree; when the matching degree of the two is higher than the threshold value, inputting verification is passed; otherwise, outputting verification failure.

Image information correction and spectral information correction include image processing methods of ambient mean compensation (binding). Therefore, in the preferred embodiment of the present invention, the living fingerprint detection method further includes the steps of image information correction and spectral information correction. In the correction of image information, the intensity value of a spectral pixel (which can be understood as a filter structure formed in correspondence with a physical pixel) is replaced with an intensity value obtained by a weighted average of intensities of nearby ordinary physical pixels, thereby generating corrected image information (image data). The average value can be obtained by selecting a plurality of adjacent (e.g. 4, 8, 24, 80) common physical pixels for averaging, and when the number is greater than 4, the weighted kernel used for weighted averaging can be a uniform kernel (all physical pixels Ping Quan) or a gaussian kernel. For example, in the embodiment shown in fig. 11, a gaussian kernel of 5*5 may be used, as shown in table 1, where the middle 0 represents a spectrum pixel, that is, where the light intensity information (image information) needs to be obtained by gaussian kernel weighted average of the light intensity information (image information) of 24 physical pixels around, that is, the light intensity information value of the relevant material pixel is multiplied by the sum of corresponding coefficients and divided by the sum of weights.

TABLE 1

For the acquisition of spectral information, it is necessary to avoid the effect of the brightness of the pattern at different positions on the spectral verification. For example, the different reflectivities of the fingerprint valleys and the fingerprint ridges cause different brightness and darkness, and thus may affect the judgment of the spectrum signal of the object to be measured. The living fingerprint detection method according to the preferred embodiment of the present invention further includes a step of correcting the spectral pixel intensities. For example, the intensity value of the current spectral pixel may be divided by or subtracted from the value of the weighted average (binning) of neighboring normal pixels to obtain the relative intensity, which may be subsequently processed as modified spectral information. Furthermore, the correction spectrum information can be screened according to a specific rule, and the oversized value and the undersized value are removed, so that the effectiveness of the correction spectrum information is improved. Taking fig. 11 as an example, the value of 8 physical pixels around the spectrum pixel may be taken as an average intensity value, and the intensity value of the spectrum pixel may be divided by or subtracted from the average intensity value of 8 physical pixels to obtain corrected spectrum information.

Referring to fig. 14, the living body fingerprint detection method of the present invention further includes a step of a living body judgment algorithm. The effective corrected spectrum parameter (may also be understood as corrected spectrum information) extracted from the processed raw data (light intensity information) is calculated, and a correlation coefficient R (for example, pearson correlation coefficient may be adopted) with the reference spectrum information is calculated, and when the correlation coefficient R is greater than a corresponding threshold value, it is determined as a living body, otherwise it is determined as a non-living body. Because the invention needs to calculate the correlation coefficient R, the input information and the detection information are one-dimensional vectorization.

Further, the living fingerprint detection method of the present invention further includes the steps of threshold selection and use. For different times of recording information, due to potential changes of various conditions during recording, the noise power ratio (signal to noise ratio) is different each time data are collected. When the signal-to-noise ratio is high, the correlation coefficient between the corresponding spectrum information and other recorded reference spectrum information is generally high; otherwise, when the signal-to-noise ratio is low, the corresponding correlation coefficient is generally low. Therefore, the judgment using the uniform threshold value is liable to introduce erroneous judgment. In this way, the method eliminates the dynamic selection of a threshold value and the corresponding use method, and can perform living body verification more accurately.

Under the condition of n effective entries (for example, a group of effective entries is 10 entries), calculating the correlation coefficient R of the spectral information which is entered at this time and the spectral information which is entered at other n-1 times, taking the lowest correlation coefficient R_min, and carrying out specific formula calculation with the system setting parameter k to obtain the judging threshold value R_t of the comparison of the entries. In actual use, the data to be tested and the n times of recorded data are respectively calculated to be related coefficients, the related coefficients are respectively compared with corresponding judgment thresholds R_t (1-10), when n-1 or more are larger than the corresponding judgment thresholds, the test is considered to be a living body, otherwise, the test is judged to be a non-living body.

Further, the living body fingerprint detection method of the present invention further includes a fingerprint input step. And during recording, judging the consistency of the recorded spectrum features. Due to the interference of potential ambient light or random factors such as finger states to be recorded, unstable factors can be caused to recorded spectrum information, and thus experience such as use accuracy is affected. Therefore, it is necessary to judge the consistency of the spectrum information at the time of recording.

For example, the entry requires a set of N (2-20) consecutive entries with the same finger. And when the input is performed each time, processing the input spectral parameters according to the comparison flow, calculating the correlation coefficient of the input data and the input corresponding spectral parameter data, and if the correlation coefficient is smaller than the system set value m, failing the input.

Alternatively, the correlation coefficient of each entry data may be compared with the entry data of the database corresponding to the specific prosthetic material already existing in the system, and if a plurality of (n=1 to 3) data correlation coefficients are greater than the system threshold q, the entry fails. If the input fails for a plurality of times (n=2 to 5), the input fails and a group of inputs needs to be carried out again.

Further, the living fingerprint detection method of the present invention further includes a step of inputting data update. The entered data needs to be updated in view of the possible changes in the system or test object over time. For example, after each time of judging that the detection is successful, calculating a mean value R_atest of correlation coefficients of the spectral parameters judged at this time and comparison of 10 pieces of input data stored in the system, comparing the mean value R_a1-10 of correlation coefficients among the 10 pieces of input data, if R_atest is greater than 1 or more of R_a1-10, selecting the smallest one of R_a1-10, and replacing the corresponding input data with the data tested at this time. It should be noted that 10 pieces of input data are only used as examples and not limited to 10 pieces, and may be greater than 10 pieces, or less than 10 pieces, and they may be adjusted according to the requirement.

The living body fingerprint detection method according to the above-described preferred embodiment of the present invention is explained in the following description with reference to fig. 15 of the drawings accompanying the present invention. The living body fingerprint detection method comprises the following steps:

(a) Acquiring light intensity information acquired by fingerprints;

(b) Acquiring fingerprint images and spectrum information based on the acquired light intensity information; and

(c) And comparing the fingerprint image and the spectrum information with the input reference information, and when the matching degree is higher than a threshold value, inputting verification, otherwise, outputting verification failure.

In the above living fingerprint detection method, the detection method further includes: and correcting the light intensity information, wherein the light intensity information correction comprises an image processing mode of surrounding mean value compensation (binding). In image information correction, the intensity of a spectral pixel is replaced with an intensity value that is a weighted average of the intensities of nearby ordinary physical pixels, thereby generating a corrected picture parameter.

In the above living fingerprint detection method, the detection method further includes: and correcting the spectrum information corresponding to the spectrum pixel, namely dividing or subtracting the intensity value of the current spectrum pixel by the intensity value of the adjacent common pixel weighted average (binning), and obtaining the relative intensity to be used as corrected spectrum information for subsequent processing.

In the above living fingerprint detection method, the detection method further includes: calculating a correlation coefficient R formed by the effective correction spectrum information extracted from the processed original data and the recorded reference spectrum information, and judging as a living body when the correlation coefficient R is larger than a corresponding threshold value; otherwise, the non-living body is judged.

In the above living fingerprint detection method, the detection method further includes the steps of:

under the condition of n times of effective recording, carrying out correlation coefficient R calculation on the spectrum information of each time and other n-1 times, taking the lowest correlation coefficient R_min, carrying out specific formula calculation on the lowest correlation coefficient R_min and a system setting parameter k to obtain a judging threshold value R_t of the recording comparison, and when n-1 or more than one of the spectrum information is larger than the corresponding judging threshold value, considering the test as a living body, otherwise, judging the test as a non-living body, wherein the specific formula is as follows: r_t=max (r_min, k).

In the above living fingerprint detection method, the detection method further includes a step of judging consistency of the spectral features:

and when the input is performed each time, processing the input spectrum information according to a comparison flow, calculating the correlation coefficient of the input data and the input spectrum information, and if the correlation coefficient is smaller than a system set value m, failing the input. Optionally, the spectral parameters at each entry are compared with the spectral parameters of the specific prosthetic material already present in the system, and if there is a data correlation coefficient greater than the system threshold q, the entry fails.

In the above living fingerprint detection method, the detection method further includes the step of inputting data update:

after each time of judging and detecting success, carrying out correlation coefficient calculation on the spectrum information judged at the time and n pieces of input data, obtaining a corresponding mean value R_atest, comparing the average value R_a1-n with the correlation coefficient mean value R_a1-n between the n pieces of input data, and if R_atest is greater than 1 or more of R_a1-n, replacing the smallest data in R_a1-n in the input data with the data tested at the time.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are by way of example only and are not limiting. The objects of the present invention have been fully and effectively achieved. The functional and structural principles of the present invention have been shown and described in the examples and embodiments of the invention may be modified or practiced without departing from the principles described.

Claims (20)

1. A living body fingerprint detection device, characterized by comprising:

the light source emits light generated by the light source to the fingerprint to be detected; and

the identification module comprises at least one sensor and an optical component, wherein the optical component is positioned on an optical path of the at least one sensor, reflected light of the fingerprint to be detected reaches the at least one sensor through the optical component, and the at least one sensor performs living fingerprint judgment based on the received spectral information of the reflected light.

2. The living fingerprint detection device according to claim 1, wherein the identification module further comprises a holder and a wiring board, wherein the sensor is electrically connected to the wiring board, the holder is provided to the wiring board, the optical component is provided to the holder, the optical component is supported by the holder, and the optical component is held in a photosensitive path of the sensor.

3. The living fingerprint detection device according to claim 2, wherein the light source is provided to the wiring board.

4. The living fingerprint detection device according to claim 3, wherein the identification module further comprises a transparent cover plate and a supporting member, wherein the supporting member is sleeved outside the bracket, and the transparent cover plate is supported above the optical component by the supporting member.

5. The living fingerprint detection device according to claim 3, wherein the identification module further comprises a transparent cover, wherein the transparent cover is disposed on the support and is supported by the support above the optical component.

6. The living fingerprint detection device according to claim 2, wherein the holder includes a holder main body, a lens support portion and a cover support portion, wherein the lens support portion is located at an upper end of the cover support portion, and the light source and the second wiring board are provided to the lens support portion of the holder.

7. The living fingerprint detection device according to claim 4 or 5, wherein the wiring board further comprises a first wiring board and a second wiring board, wherein the sensor is provided to the first wiring board, and the light source is provided to the second wiring board.

8. The living fingerprint detection device according to claim 7, wherein the wiring board further comprises at least one connection wire, wherein the connection wire electrically connects a first wiring board and the second wiring board.

9. The living fingerprint detection device according to claim 7, wherein the wiring board further comprises a flexible board, wherein the flexible board is provided to the first wiring board and the second wiring board, and the first wiring board and the second wiring board are electrically connected through the flexible board.

10. The living fingerprint detection device according to claim 1, wherein the identification module further comprises at least one light homogenizing member, wherein the at least one light homogenizing member is disposed in a light emitting path of the light source.

11. The living body fingerprint detection device according to any one of claims 1-10, wherein the sensor is a spectral sensor.

12. The living fingerprint detection device according to claim 1, wherein the identification module comprises a spectrum sensor, an imaging sensor and a spectroscopic element, wherein the spectroscopic element is located in an optical path of the spectrum sensor and the imaging sensor, the detection light is divided into a first detection light and a second detection light by the spectroscopic element, wherein the first detection light reaches the spectrum sensor after being turned by the spectroscopic element, the second detection light reaches the imaging sensor after being transmitted by the spectroscopic element, the spectrum sensor obtains spectrum information of the object to be detected through the first detection light, and the imaging sensor obtains image information of the object to be detected through detecting the second detection light.

13. A living fingerprint detection method, characterized by comprising:

(a) Acquiring light intensity information acquired by fingerprints;

(b) Acquiring fingerprint images and spectrum information based on the acquired light intensity information; and

(c) And comparing the fingerprint image and the spectrum information with the input reference information, and when the matching degree is higher than a threshold value, inputting verification, otherwise, outputting verification failure.

14. The living fingerprint detection method according to claim 13, wherein the detection method further comprises: and correcting the light intensity information, wherein the light intensity information correction comprises an image processing mode of surrounding average value compensation.

15. The living fingerprint detection method according to claim 14, wherein in the image information correction, the intensity value of the spectral pixel is replaced with an intensity value obtained by a weighted average of intensities of nearby ordinary physical pixels, thereby generating a corrected picture parameter for obtaining the fingerprint image.

16. The living fingerprint detection method according to claim 14, wherein the detection method further comprises: and correcting the spectrum information corresponding to the spectrum pixel, dividing or subtracting the intensity value of the current spectrum pixel by the weighted average intensity value of the adjacent common pixels to obtain the relative intensity, and taking the relative intensity as corrected spectrum information to carry out subsequent processing.

17. The living fingerprint detection method according to claim 16, wherein the detection method further comprises: calculating a correlation coefficient R formed by the effective correction spectrum information extracted from the processed original data and the recorded reference spectrum information, and judging as a living body when the correlation coefficient R is larger than a corresponding threshold value; otherwise, the non-living body is judged.

18. The living fingerprint detection method according to claim 16, wherein the detection method further comprises the steps of:

under the condition of n times of effective recording, carrying out correlation coefficient R calculation on the spectrum information of each time and other n-1 times, taking the lowest correlation coefficient R_min, carrying out specific formula calculation on the lowest correlation coefficient R_min and a system setting parameter k to obtain a judging threshold value R_t of the recording comparison, and when n-1 or more than one of the spectrum information is larger than the corresponding judging threshold value, considering the test as a living body, otherwise, judging the test as a non-living body, wherein the specific formula is as follows: r_t=max (r_min, k).

19. The living fingerprint detection method according to claim 13, wherein the detection method further comprises the step of consistency judgment of spectral features:

and when the input data is input each time, processing the input spectrum information according to a comparison flow, calculating the correlation coefficient of the input data and the input spectrum information, and if the correlation coefficient is smaller than a system set value m, failing the input.

20. The living fingerprint detection method according to claim 13, wherein the detection method further comprises the step of entering a data update:

after each time of judging and detecting success, carrying out correlation coefficient calculation on the spectrum information judged at the time and n pieces of input data, obtaining a corresponding mean value R_atest, comparing the average value R_a1-n with the correlation coefficient mean value R_a1-n between the n pieces of input data, and if R_atest is greater than 1 or more of R_a1-n, replacing the smallest data in R_a1-n in the input data with the data tested at the time.