Optical coherence tomography analysis device, optical coherence tomography analysis method, and recording medium

Abstract

This optical interference tomographic imaging analysis device (10) comprises: an acquisition means (301) for carrying out optical interference tomographic imaging through irradiation with a light beam and acquiring three-dimensional luminance data of skin; a position extraction means (302) for extracting the epiderm position of the skin for each tomographic image obtained through fast-axis scanning of the light beam in the three-dimensional luminance data of the skin; a connection means (303) for adjusting the relative positions of the tomographic images and connecting the tomographic images on the basis of the result of extraction of the epiderm position of the skin, thereby generating connected three-dimensional data; a planarization means (304) for executing conversion processing on the connected three-dimensional data to planarize the epiderm on the basis of the result of extraction the epiderm position of the skin, thereby generating planarized three-dimensional data; and a pattern extraction means (305) for extracting, from the planarized three-dimensional data, a pattern of the skin that corresponds to a prescribed depth of extraction.

Description

[Technical Field]

[0001] The present disclosure relates to the technical fields of an optical coherence tomography analysis device, an optical coherence tomography analysis method, and a recording medium. [Background technology]

[0002] Known devices of this type are those that capture images of skin patterns (e.g., fingerprints) of living organisms. For example, Patent Document 1 discloses a fingerprint imaging device that captures a fingerprint image of the epidermis in a non-contact manner by passing a fingertip through a predetermined location without contacting a glass plate or the like. Patent Documents 2 to 4 also disclose fingerprint imaging devices that use optical coherence tomography (OCT) technology to perform three-dimensional tomographic imaging of the fingertip and capture a fingerprint image of the dermis. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2009 / 112717 [Patent Document 2] International Publication No. 2016 / 204176 [Patent Document 3] International Publication No. 2020 / 170439 [Patent Document 4] International Publication No. 2021 / 019788 Summary of the Invention [Problem to be solved by the invention]

[0004] This disclosure aims to improve upon the techniques disclosed in the prior art documents. [Means for solving the problem]

[0005] One aspect of the optical coherence tomography analysis device disclosed herein comprises: an acquisition means that performs optical coherence tomography by irradiating skin with a light beam while scanning it two-dimensionally, and acquires three-dimensional luminance data of the skin; a position extraction means that extracts the epidermis position of the skin for each tomographic image obtained by scanning the light beam in the fast axis direction in the three-dimensional luminance data of the skin; a connection means that generates connected three-dimensional data by adjusting the relative positions between the tomographic images and connecting the tomographic images based on the extraction result of the epidermis position of the skin; a flattening means that generates flattened three-dimensional data by performing a conversion process on the connected three-dimensional data to flatten the epidermis based on the extraction result of the epidermis position of the skin; and a pattern extraction means that extracts the skin pattern according to a predetermined extraction depth from the flattened three-dimensional data.

[0006] One aspect of the optical coherence tomography imaging analysis method disclosed herein is an optical coherence tomography imaging analysis method executed by at least one computer, which performs optical coherence tomography imaging by irradiating skin with a light beam while scanning it in two dimensions, obtains three-dimensional luminance data of the skin, extracts the position of the skin's epidermis for each tomographic image obtained by scanning the light beam in the fast axis direction in the three-dimensional luminance data of the skin, generates connected three-dimensional data by adjusting the relative positions between the tomographic images and connecting the tomographic images based on the extraction result of the skin's epidermis position, generates flattened three-dimensional data by performing a conversion process on the connected three-dimensional data to flatten the epidermis based on the extraction result of the skin's epidermis position, and extracts the skin pattern according to a predetermined extraction depth from the flattened three-dimensional data.

[0007] One aspect of a recording medium of the disclosure is a recording medium having recorded thereon a computer program for causing at least one computer to execute an optical coherence tomography analysis method, the optical coherence tomography analysis method comprising: performing optical coherence tomography by irradiating skin with a light beam while scanning it two-dimensionally; acquiring three-dimensional luminance data of the skin; extracting an epidermis position of the skin for each tomographic image obtained by scanning the light beam in the fast axis direction in the three-dimensional luminance data of the skin; adjusting the relative positions between the tomographic images based on the extraction result of the epidermis position of the skin to connect the tomographic images to generate connected three-dimensional data; performing a conversion process on the connected three-dimensional data to flatten the epidermis based on the extraction result of the epidermis position of the skin to generate flattened three-dimensional data; and extracting the skin pattern according to a predetermined extraction depth from the flattened three-dimensional data. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram showing an example of the hardware configuration of an optical coherence tomography analysis apparatus according to a first embodiment. [Figure 2] 2 is a schematic diagram showing an example of the configuration of an optical coherence tomographic imaging section according to the first embodiment. FIG. [Figure 3] FIG. 2 is a block diagram showing the functional configuration of an optical coherence tomography analysis unit according to the first embodiment. [Figure 4] 6 is a flowchart showing the flow of a fingerprint extraction operation performed by an optical coherence tomography analysis unit according to the first embodiment. [Figure 5] 3 is a plan view showing an example of three-dimensional luminance data acquired by the optical coherence tomography imaging section according to the first embodiment. FIG. [Figure 6] 3 is a plan view showing an example of extraction of an epidermis position by an optical coherence tomography analysis unit according to the first embodiment. FIG. [Figure 7] 3 is a three-dimensional diagram showing an example of connection of tomographic images obtained by an optical coherence tomography analysis unit according to the first embodiment. FIG. [Figure 8] 4 is a plan view showing an example of flattening conversion processing by an optical coherence tomography imaging analysis unit according to the first embodiment. FIG. [Figure 9] 3 is a plan view showing an example of extraction of a fingerprint image by an optical coherence tomography analysis unit according to the first embodiment. FIG. [Figure 10] FIG. 10 is a block diagram showing the configuration of an optical coherence tomography analysis apparatus according to a second embodiment. [Figure 11] 10 is a flowchart showing the flow of a collation operation performed by an optical coherence tomography analysis unit according to the second embodiment. [Figure 12] FIG. 10 is a block diagram showing the configuration of an optical coherence tomography analysis apparatus according to a third embodiment. [Figure 13] FIG. 10 is a block diagram showing the configuration of an optical coherence tomography analysis apparatus according to a fourth embodiment. [Figure 14] FIG. 10 is a block diagram showing the configuration of an optical coherence tomography analysis apparatus according to a fifth embodiment.

[0009] Hereinafter, embodiments of an optical coherence tomography analysis apparatus, an optical coherence tomography analysis method, and a recording medium will be described with reference to the drawings.

[0010] First Embodiment An optical coherence tomography analysis apparatus according to a first embodiment will be described with reference to FIGS.

[0011] (Hardware configuration) First, the hardware configuration of an optical coherence tomography analysis apparatus according to the first embodiment will be described with reference to Fig. 1. Fig. 1 is a block diagram showing an example of the hardware configuration of the optical coherence tomography analysis apparatus according to the first embodiment.

[0012] In Fig. 1, an optical coherence tomography imaging analysis apparatus 1 according to the first embodiment is configured as an apparatus capable of imaging the skin of a living body using a three-dimensional measurement technique such as OCT and extracting a skin pattern from the three-dimensional data obtained by imaging. The type of skin pattern is not particularly limited and may be, for example, a fingerprint or palm print. However, for the sake of convenience, the following description will be given assuming that a fingerprint is extracted. The optical coherence tomography imaging analysis apparatus 1 according to the first embodiment is configured to include an optical coherence tomography imaging unit 2 and an optical coherence tomography analysis unit 3. Note that the components of the optical coherence tomography imaging analysis apparatus 1 may be connected to each other via buses, wiring, driving devices, etc. (not shown).

[0013] The optical coherence tomography imaging unit 2 is configured to be able to image the skin of a living body using a three-dimensional measurement technique such as OCT. The optical coherence tomography imaging unit 2 is configured to be able to output three-dimensional brightness data obtained by imaging to the optical coherence tomography analysis unit 3. The specific configuration of the optical coherence tomography imaging unit 2 will be described in detail later.

[0014] The optical coherence tomography analysis unit 3 is configured to be able to extract skin patterns (e.g., fingerprints on the epidermis or dermis) of a living body by analyzing the three-dimensional brightness data acquired from the optical coherence tomography imaging unit 2. The optical coherence tomography analysis unit 3 may be a computer such as a data processing server, a desktop PC (Personal Computer), a notebook PC, or a tablet PC. The optical coherence tomography analysis unit 3 is a computer that performs calculations, control, and storage, and includes a processor 101, a memory 102, a communication I / F (Interface) 103, an input device 104, and an output device 105.

[0015] The processor 101 is a processing device including one or more arithmetic processing circuits, such as a central processing unit (CPU), a graphics processing unit (GPU), a field-programmable gate array (FPGA), an application specific integrated circuit (ASIC), etc. The processor 101 performs predetermined calculations according to programs stored in a memory 102 or the like, and also has the function of controlling each part of the optical coherence tomography analysis unit 3.

[0016] The memory 102 may include a volatile storage medium that provides a temporary memory area required for the operation of the processor 101, and a nonvolatile storage medium that non-temporarily stores information such as data to be processed and an operating program for the optical coherence tomography analysis unit 3. Examples of the volatile storage medium include RAM (Random Access Memory). Examples of the nonvolatile storage medium include ROM (Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), flash memory, etc.

[0017] The communication I / F 103 is a communication interface based on standards such as Ethernet (registered trademark), Wi-Fi (registered trademark), Bluetooth (registered trademark), etc. The communication I / F 103 is a module for communicating with other devices such as the optical coherence tomography imaging unit 2.

[0018] The input device 104 is a keyboard, a pointing device, a button, etc., and is used by the user to operate the optical coherence tomography analysis unit 3. Examples of pointing devices include a mouse, a trackball, a touch panel, and a pen tablet.

[0019] The output device 105 is a device that presents information to a user, such as a display device, a speaker, etc. Examples of the display device include a liquid crystal display, an OLED (Organic Light Emitting Diode) display, etc. The input device 104 and the output device 105 may be integrally formed as a touch panel.

[0020] Note that the hardware configuration shown in FIG. 1 is an example, and other devices may be added, or some devices may not be provided. Furthermore, some devices may be replaced with other devices having similar functions. Furthermore, some functions of this embodiment may be provided by other devices via a network, or the functions of this embodiment may be distributed and realized among multiple devices. For example, the optical coherence tomography imaging unit 2 and the optical coherence tomography analysis unit 3 may be integrated into one device. In this way, the hardware configuration shown in FIG. 1 can be modified as appropriate.

[0021] (Configuration of optical coherence tomography imaging unit) Next, the configuration of the optical coherence tomography imaging unit 2 according to the first embodiment will be specifically described with reference to Fig. 2. Fig. 2 is a schematic diagram showing an example of the configuration of the optical coherence tomography imaging unit according to the first embodiment. Note that the configuration diagram shown in Fig. 2 shows only one example of a measuring device using OCT technology, and other measuring device configurations may also be used.

[0022] OCT technology utilizes the interference between object light and reference light to identify the position in the optical axis direction, i.e., the depth direction, of the area where the object light is scattered (light scattering point) in the object being measured, and obtain spatially resolved structural data in the depth direction inside the object being measured. OCT technologies include time domain (TD-OCT) and Fourier domain (FD-OCT), but FD-OCT is more promising due to its high speed and high sensitivity. In FD-OCT, when the object light and reference light interfere, the interference light spectrum is measured over a wide wavelength band, and structural data in the depth direction is obtained by Fourier transforming this. Methods for obtaining the interference light spectrum include spectral domain (SD-OCT), which uses a spectroscope, and swept source (SS-OCT), which uses a wavelength-swept light source.

[0023] Furthermore, by scanning the object light beam irradiation position on the object in an in-plane direction perpendicular to the depth direction of the object, it is possible to obtain tomographic structure data that is spatially resolved in the in-plane direction and spatially resolved in the depth direction, i.e., three-dimensional tomographic structure data of the object.

[0024] 2 shows an SS-OCT optical coherence tomography imaging unit 2. In the optical coherence tomography imaging unit 2, a wavelength-swept optical pulse is generated by a wavelength-swept laser source 201. The light emitted from the wavelength-swept laser source 201 passes through an optical coherence and light-receiving unit 202 and an optical beam scanning unit 203, and is irradiated onto a measurement object 205 and scattered. A portion of this scattered light returns to the optical coherence and light-receiving unit 202 and undergoes photoelectric conversion. An electrical signal output from the optical coherence and light-receiving unit 202 is converted into data by a signal processing and control unit 204 and sent to the optical coherence tomography analysis unit 3.

[0025] The wavelength-swept laser light source 201 generates optical pulses whose wavelength increases from 1250 nm to 1350 nm over a duration of 5 μs, and generates these optical pulses every 10 μs at a repetition rate of 100 kHz.

[0026] In the optical interference / light receiving unit 202, light emitted from the wavelength swept laser light source 201 is input to the branching / converging unit 212 via the circulator 211. In the branching / converging unit 212, the input light is branched into an object light R211 and a reference light R221. The object light R211 passes through a fiber collimator 215 and an irradiation optical system 216 consisting of a scanning mirror and a lens, and is then irradiated onto the measurement object 205. Then, the object light R231 scattered by the measurement object 205 returns to the branching / converging unit 212. On the other hand, the reference light R221 returns to the branching / converging unit 212 via the reference light mirror 213. Therefore, in the branching / converging unit 212, the object light R231 scattered from the measurement object 205 and the reference light R241 reflected by the reference light mirror 213 interfere with each other, generating interference lights R251 and R261. That is, the intensity ratio between the interference light R251 and the interference light R261 is determined by the phase difference between the object light R231 and the reference light R241. The interference light R251 passes through a circulator 211, and the interference light R261 is directly input to a two-input balanced photodetector 214. A voltage corresponding to the intensity difference between the interference light R251 and the interference light R261 is output from the balanced photodetector 214 and input to the signal processing and control unit 204.

[0027] The signal processing and control unit 204 generates interference light spectrum data based on information regarding wavelength changes in the light emitted from the wavelength swept laser light source 201 and information regarding changes in the intensity ratio between the interference light R251 and R261. This interference light spectrum data is Fourier transformed to obtain data indicating the intensity of the backscattered light (object light) at different positions in the depth direction (Z direction). (Hereinafter, the operation of obtaining data indicating the intensity of the backscattered light (object light) in the depth direction (Z direction) at a position on the measurement object 205 will be referred to as an "A-scan.") To generate an A-scan waveform every 10 μs of the optical pulse repetition period, an electrical signal with a repetition frequency of 100 kHz is supplied from the wavelength swept laser light source 201 to the signal processing and control unit 204 as an A-scan trigger signal. The A-scan waveform obtained indicates the intensity of the backscattered object light at Nz locations.

[0028] Furthermore, the irradiation position of the object light beam R231 is scanned on the measurement object 205 by the irradiation optical system 216. The signal processing and control unit 204 controls the irradiation optical system 216 in response to an A-scan trigger signal supplied from the wavelength swept laser light source 201 to move the irradiation position of the object light beam R231 in the scanning line direction (the fast axis direction of scanning, the X direction). By repeatedly performing A-scan operations and connecting the A-scan waveforms for each object light beam irradiation position, a two-dimensional map of the intensity of backscattered light (object light) in the scanning line direction and depth direction is obtained as a tomographic image (hereinafter, the operation of repeatedly performing A-scan operations in the scanning line direction (the fast axis direction of scanning, the X direction) and connecting the measurement results is referred to as a "B scan"). If the number of object light beam irradiation positions per B-scan is Nx, the tomographic image obtained by the B-scan becomes two-dimensional brightness data indicating the object light backscattering intensity at Nz × Nx points.

[0029] Furthermore, by repeatedly performing B-scan operations while moving the irradiation position of the object light beam R231 using the irradiation optical system 216 not only in the scanning line direction but also in a direction perpendicular to the scanning line (slow axis direction of scanning, Y direction), and connecting the B-scan measurement results, three-dimensional tomographic structure data can be obtained (hereinafter, the operation of repeatedly performing B-scan operations in the direction perpendicular to the scanning line (Y direction) and connecting the measurement results will be referred to as a "C-scan"). If the number of B-scans per C-scan is Ny, the tomographic structure data obtained by the C-scan will be three-dimensional brightness data indicating the object light backscattering intensity at Nz × Nx × Ny points.

[0030] If the object light beam irradiation positions in the X direction are, for example, 300, and the object light beam irradiation positions in the Y direction are, for example, 300, the time required for one B scan is 3 ms since it is the equivalent of 300 A scans, and the time required for one C scan is 900 ms since it is the equivalent of 300 B scans. When measuring a person's finger without contact, it may be possible to reduce the amount of finger movement over 3 ms, but it is difficult to reduce the amount of finger movement over 900 ms.

[0031] (Functional configuration of the optical coherence tomography analysis unit) Next, the functional configuration of the optical coherence tomography analysis unit 3 according to the first embodiment will be described with reference to Fig. 3. Fig. 3 is a block diagram showing the functional configuration of the optical coherence tomography analysis unit according to the first embodiment.

[0032] 3, the optical coherence tomography analysis unit 3 according to the first embodiment includes, as functional blocks for realizing its functions, a three-dimensional luminance data acquisition unit 301, an epidermis position extraction unit 302, a tomographic image connection unit 303, a flattening conversion processing unit 304, and a fingerprint image extraction unit 305. Each of the three-dimensional luminance data acquisition unit 301, the epidermis position extraction unit 302, the tomographic image connection unit 303, the flattening conversion processing unit 304, and the fingerprint image extraction unit 305 may be realized by, for example, the above-mentioned processor 101 (see FIG. 1).

[0033] The three-dimensional luminance data acquisition unit 301 is configured to be able to acquire three-dimensional luminance data obtained by measuring the skin of a living body with the optical coherence tomography imaging unit 2. The three-dimensional luminance data acquisition unit 301 may control the optical coherence tomography imaging unit 2 to acquire new three-dimensional luminance data, or may acquire three-dimensional luminance data by reading out three-dimensional luminance data acquired in advance from a storage medium such as the memory 102.

[0034] The epidermis position extraction unit 302 extracts the epidermis position for each tomographic image (specifically, for each B-scan tomographic image obtained by scanning the light beam in the fast axis direction) of the three-dimensional luminance data acquired by the three-dimensional luminance data acquisition unit 301. The epidermis position extraction unit 302 may extract, for example, coordinates indicating the epidermis position in the tomographic image.

[0035] The tomographic image connection unit 303 is configured to be able to adjust the relative positions between the tomographic images and connect the tomographic images based on the epidermis position extracted by the epidermis position extraction unit 302. More specifically, the tomographic image connection unit 303 adjusts the relative positions based on the extracted epidermis position so as to reduce the difference in epidermis position between adjacent B-scan tomographic images. Then, the tomographic image connection unit 303 connects the adjacent B-scan tomographic images whose positions have been adjusted, thereby generating three-dimensional brightness data (hereinafter referred to as "connected three-dimensional data" as appropriate).

[0036] The flattening conversion processing unit 304 is configured to be able to perform conversion processing to flatten the epidermis of the connected three-dimensional data based on the epidermis position extracted by the epidermis position extraction unit 302. The flattening conversion processing unit 304 may flatten the epidermis, for example, by performing a parallel translation in the Z direction (i.e., the depth direction) to reset the epidermis position to the origin. Hereinafter, the three-dimensional luminance data obtained by performing such conversion processing will be referred to as "flattened three-dimensional data."

[0037] Fingerprint image extraction unit 305 is configured to be able to extract a fingerprint image (i.e., a planar image showing the skin pattern) according to a predetermined extraction depth from the flattened three-dimensional data obtained by flattening conversion processing unit 304. The extraction depth here is a value that is set in advance depending on the extraction target, and may be set to, for example, a value corresponding to the epidermis or a value corresponding to the dermis. Fingerprint image extraction unit 305 may extract multiple fingerprint images by changing the extraction depth from one piece of flattened three-dimensional data. Furthermore, fingerprint image extraction unit 305 may extract other data indicating a fingerprint (e.g., fingerprint feature amounts) in addition to or instead of a fingerprint image.

[0038] (Operation flow) Next, the flow of the operation of extracting a fingerprint image from three-dimensional luminance data by the optical coherence tomography analysis unit 3 according to the first embodiment (hereinafter referred to as "fingerprint extraction operation") will be described with reference to Fig. 4. Fig. 4 is a flowchart showing the flow of the fingerprint extraction operation by the optical coherence tomography analysis unit according to the first embodiment.

[0039] 4, when the optical coherence tomography analysis unit 3 according to the first embodiment operates, first, the three-dimensional luminance data acquisition unit 301 acquires three-dimensional luminance data, which is the measurement result of the optical coherence tomography imaging unit 2 (step S11). The three-dimensional luminance data acquired by the three-dimensional luminance data acquisition unit 301 is output to the epidermis position extraction unit 302.

[0040] Next, the epidermis position extraction unit 302 extracts the epidermis position for each tomographic image from the three-dimensional brightness data acquired by the three-dimensional brightness data acquisition unit 301 (step S12). Information on the epidermis position extracted by the epidermis position extraction unit 302 is output to each of the tomographic image connection unit 303 and the flattening conversion processing unit 304.

[0041] Next, the tomographic image connection unit 303 adjusts the relative positions between the tomographic images based on the epidermis position extracted by the epidermis position extraction unit 302, and connects the tomographic images to generate connected three-dimensional data (step S13). The connected three-dimensional data generated by the tomographic image connection unit 303 is output to the flattening conversion processing unit 304.

[0042] Next, the flattening conversion processing unit 304 performs conversion processing to flatten the surface of the connected three-dimensional data based on the surface position extracted by the surface position extraction unit 302, and generates flattened three-dimensional data (step S14). The flattened three-dimensional data generated by the flattening conversion processing unit 304 is output to the fingerprint image extraction unit 305.

[0043] Next, fingerprint image extraction unit 305 extracts a fingerprint image according to a predetermined extraction depth from the flattened three-dimensional data obtained by flattening conversion processing unit 304 (step S15). Fingerprint image extraction unit 305 may register (store) the extracted fingerprint image as registration information. In this case, a matching process (e.g., a biometric authentication process using a fingerprint) may be executed using the registered fingerprint image. A configuration using a fingerprint image in a matching process will be described in detail in another embodiment described later.

[0044] (Specific operation example) Next, a specific example of the above-mentioned fingerprint extraction operation will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is a plan view showing an example of three-dimensional luminance data acquired by the optical coherence tomography imaging unit according to the first embodiment. Fig. 6 is a plan view showing an example of extraction of epidermis position by the optical coherence tomography analysis unit according to the first embodiment. Fig. 7 is a three-dimensional view showing an example of connection of tomographic images by the optical coherence tomography analysis unit according to the first embodiment. Fig. 8 is a plan view showing an example of flattening conversion processing by the optical coherence tomography imaging analysis unit according to the first embodiment. Fig. 9 is a plan view showing an example of extraction of fingerprint image by the optical coherence tomography analysis unit according to the first embodiment.

[0045] The optical coherence tomography imaging unit 2 captures non-contact images of a living finger and generates three-dimensional intensity data of Nx=300, Ny=300, and Nz=256. This imaging is performed by setting the optical beam scanning unit 203 of the optical coherence tomography imaging unit 2 to irradiate 300 locations in the X direction (the fast axis direction of scanning) and 300 locations in the Y direction (the slow axis direction of scanning). The interference light spectrum between the object light and the reference light is analyzed to obtain intensity data resolved into 256 locations in the Z direction, resulting in the generation of three-dimensional intensity data of the living finger. This three-dimensional intensity data can be considered as a set of Ny=300 B-scan tomographic images (Nx×Nz=300×256). Figures 5(a) to 5(c) show three of the 300 B-scan tomographic images as an example of the acquired three-dimensional intensity data.

[0046] The epidermis position extraction unit 302 extracts the coordinates of the epidermis position for each B-scan tomographic image from the three-dimensional brightness data acquired by the three-dimensional brightness data acquisition unit 301 of the optical coherence tomography analysis unit 3. FIGS. 6(a) to 6(c) show the results of extracting the epidermis position for three of the 300 B-scan tomographic images. When an object light beam is irradiated onto a finger without contact, the object light reflection is usually strongest at the epidermis position. For this reason, in the B-scan tomographic image with the horizontal axis X and the vertical axis Z, the Z value Zs' at which the object light backscattering intensity (brightness) is maximized for each X value is selected. However, because the brightness is often maximized at a position other than the epidermis due to the influence of noise, an outlier removal process is performed taking into account that the epidermis is continuous.

[0047] Based on the epidermis position Zs extraction result extracted for each (X, Y) value by the epidermis position extraction unit 302 of the optical coherence tomography analysis unit 3, the tomographic image connection unit 303 adjusts the relative positions between adjacent B-scan tomographic images. When the epidermis position curve extracted on the B-scan tomographic image is Zs(X), adjustment is made so that the difference between adjacent tomographic images is minimized. The tomographic image connection unit 303 connects the tomographic images whose positions have been adjusted in this way to generate connected three-dimensional data (see FIG. 7).

[0048] The flattening conversion processing unit 304 performs conversion on the connected 3D data generated by the tomographic image connection unit 303 of the optical coherence tomography analysis unit 3 based on the extracted epidermis position so that the epidermis position becomes flat. That is, it performs a parallel translation in the Z direction to reset the epidermis position Zs extracted for each (X, Y) value to the origin. In this way, the tomographic image connection unit 303 obtains flattened 3D data. Figures 8(a) to 8(c) show the results of performing the epidermis flattening conversion process on three of the 300 B-scan tomographic images.

[0049] The fingerprint image extraction unit 305 extracts at least one of an epidermal fingerprint image and a dermal fingerprint image from the flattened three-dimensional data that has undergone epidermal flattening conversion processing. In flattened three-dimensional data that has undergone conversion processing based on the epidermis, Z=0 corresponds to the epidermal position. Therefore, the fingerprint image extraction unit 305 extracts the luminance data on the XY plane at Z=0 as the epidermal fingerprint image. The dermal fingerprint image can be extracted by selecting the Z position based on the feature of the image sliced ​​along the XY plane. In this case, an example of the feature used can be the stripe pattern definition of a stripe pattern in a fingerprint or the like. The stripe pattern definition can be, for example, a feature such as OCL (Orientation Certainty Level) that indicates that there are many stripes formed by light and dark in the image and that they have the same shape. The fingerprint image extraction unit 305 extracts the luminance data on the XY plane at the Z value selected as the dermal position as the dermal fingerprint image. The dermal position can also be selected by dividing the XY plane into appropriate small regions and performing the selection for each small region. The epidermal fingerprint image extracted by the above procedure is shown in FIG. 9(a), and the dermal fingerprint image is shown in FIG. 9(b).

[0050] (Technical Effects) Next, the technical effects obtained by the optical coherence tomography analysis apparatus 1 according to the first embodiment will be described.

[0051] Devices that image living skin often fail to produce good images depending on the skin's condition. For example, good images cannot be obtained if the epidermis is dirty, rough, or wrinkled. In particular, when using OCT technology, generating three-dimensional tomographic imaging data while scanning with a light beam takes time. Therefore, if measurements are taken without fixing the finger in a non-contact manner, the finger's position will move during the light beam scan, creating a technical problem. Furthermore, when scanning without touching the fingertip to a glass plate or other surface, the dermal fingerprint is located on a curved surface beneath the skin, making it difficult to accurately extract a flat fingerprint image.

[0052] However, with the optical coherence tomography imaging analysis device 1 according to this embodiment, as described above, the position of the finger's epidermis is extracted for each B-scan tomographic image, and the relative positions of adjacent B-scan tomographic images are adjusted taking into account that the epidermis is continuous. Here, the B-scan obtained by a single scan in the fast axis direction is short, so the influence of finger movement is small. Therefore, the above-described operation allows for the acquisition of three-dimensional intensity data in which the influence of finger movement is significantly suppressed. Furthermore, by performing a flattening conversion process based on the extracted epidermis position, it becomes possible to extract dermal fingerprints and the like that exist on the curved surface under the skin.

[0053] Second Embodiment An optical coherence tomography analysis apparatus 1 according to the second embodiment will be described with reference to Figures 10 and 11. The second embodiment differs from the first embodiment described above only in some of its configurations and operations, and other parts may be the same as those of the first embodiment. Therefore, the following will describe in detail the parts that differ from the first embodiment already described, and will omit a description of other overlapping parts as appropriate.

[0054] (Device configuration) First, the configuration of an optical coherence tomography analysis apparatus 1 according to the second embodiment will be described with reference to Fig. 10. Fig. 10 is a block diagram showing the configuration of an optical coherence tomography analysis apparatus according to the second embodiment. Note that in Fig. 10, the same elements as those shown in Fig. 3 are denoted by the same reference numerals.

[0055] 10, the optical coherence tomography analysis apparatus 1 according to the second embodiment includes an optical coherence tomography imaging unit 2, an optical coherence tomography analysis unit 3, a registration information database (DB) 4, and a matching unit 5. That is, the optical coherence tomography analysis apparatus 1 according to the second embodiment is configured to further include the registration information database 4 and the matching unit 5 in addition to the configuration of the first embodiment described above (see FIG. 3).

[0056] The registration information database 4 is configured as a database made up of, for example, a storage device, and is configured to be able to store fingerprint images (i.e., extracted skin patterns) extracted by the fingerprint image extraction unit 305 as registration information to be used during matching. The registration information database 4 is also configured to be able to store transformation parameters linked to the registration information. The transformation parameters are parameters related to the transformation process executed by the flattening transformation processing unit 304, and may, for example, indicate the amount of parallel movement in the Z direction when resetting the epidermis position to the origin. More specifically, the transformation parameters may, for example, be second average values ​​obtained by averaging a first average value, which is the average value of the amount of parallel movement in the Z direction for each tomographic image, over multiple tomographic images. The various types of information stored in the registration information database 4 are configured to be able to be read out as needed by the matching unit 5.

[0057] The matching unit 5 is configured to perform a matching process for matching a newly acquired fingerprint image (hereinafter referred to as a "matching image") with registration information (i.e., pre-registered fingerprint images) stored in the registration information database 4. This matching process may be performed, for example, as a biometric authentication process. Furthermore, the matching unit 5 according to this embodiment is particularly configured to perform the matching process based on transformation parameters stored in the registration information database 4. Specifically, the matching unit 5 may compare transformation parameters related to the matching image with transformation parameters associated with the registration information, and perform the matching process in order of the smallest difference. That is, the matching process may be performed in order of the registration information whose transformation parameters are close to those of the matching image. The matching unit 5 may also compare transformation parameters related to the matching image with transformation parameters associated with the registration information, and exclude from the matching process those whose difference is greater than a predetermined value. That is, registered information whose transformation parameters are far different from those of the matching image may not be used in the matching process.

[0058] The above-described registration information database 4 and the matching unit 5 may be integrally configured by using hardware common to the optical coherence tomography analysis unit 3. That is, the registration information database 4 and the matching unit 5 may be configured as functional blocks included in the optical coherence tomography analysis unit 3.

[0059] (Matching operation) Next, the flow of the collation operation performed by the collation unit 5 according to the second embodiment will be described with reference to Fig. 11. Fig. 11 is a flowchart showing the flow of the collation operation performed by the optical coherence tomography analysis unit according to the second embodiment.

[0060] 11, when the matching operation by the matching unit 5 according to the second embodiment starts, the matching unit 5 first acquires a matching image (step S21). Note that the matching image is typically acquired via the optical coherence tomography imaging unit 2 and the optical coherence tomography analysis unit 3, but the matching unit 5 may acquire the matching image via another route.

[0061] Next, the matching unit 5 acquires the transformation parameters of the match image (step S22). Then, the matching unit 5 excludes from the matching target, among the registered information registered in the registered information database 4, any registered information whose difference in transformation parameters is equal to or greater than a predetermined value (step S23). The predetermined value may be a value set in advance, or may be a value that can be changed by the user, for example. Specifically, a user who wishes to perform the matching process with more images may increase the predetermined value, thereby reducing the number of registered information pieces that are excluded from the matching target. Alternatively, a user who wishes to perform the matching process with fewer images may decrease the predetermined value, thereby increasing the number of registered information pieces that are excluded from the matching target.

[0062] Next, the matching unit 5 performs matching processing on the registered information to be matched (i.e., the registered information that was not excluded from the matching target in step S23) in order of the difference in transformation parameters between the registered information and the match image. Note that the matching unit 5 may end the matching processing when matching is successful.

[0063] (Technical Effects) Next, the technical effects obtained by the optical coherence tomography analysis apparatus 1 according to the second embodiment will be described.

[0064] 10 and 11, in the optical coherence tomography analysis apparatus 1 according to the second embodiment, the matching process of the fingerprint image is performed based on the transformation parameters. In this way, it is possible to improve the accuracy and speed of the matching process compared to when the matching process is performed without taking the transformation parameters into consideration.

[0065] <Third embodiment> An optical coherence tomography analysis apparatus 1 according to the third embodiment will be described with reference to Fig. 12. The third embodiment differs from the first and second embodiments described above only in some of its configurations and operations, and other parts may be the same as those of the first and second embodiments. Therefore, the following will describe in detail the parts that differ from the embodiments already described, and will omit a description of other overlapping parts as appropriate.

[0066] (Device configuration) First, the configuration of an optical coherence tomography analysis apparatus 1 according to the third embodiment will be described with reference to Fig. 12. Fig. 12 is a block diagram showing the configuration of an optical coherence tomography analysis apparatus according to the third embodiment. Note that in Fig. 12, the same elements as those shown in Fig. 10 are denoted by the same reference numerals.

[0067] 12, the optical coherence tomography analysis apparatus 1 according to the third embodiment includes an optical coherence tomography imaging unit 2, an optical coherence tomography analysis unit 3, a registration information database 4, and a matching unit 5. That is, the optical coherence tomography analysis apparatus 1 according to the third embodiment is configured to include the same components as those of the second embodiment (see FIG. 10) described above.

[0068] However, the registration information database 4 according to the third embodiment is configured to be able to store spatial resolution information indicating the spatial resolution at which the registration information was acquired, in addition to the registration information (i.e., the extracted fingerprint image). The spatial resolution is the resolution at which three-dimensional brightness data is acquired in the optical coherence tomography imaging unit 2. The diameter of the light beam irradiated onto the skin of a living body changes depending on the depth direction. For example, when irradiating a light beam onto a finger in a non-contact state, if the finger is bent, the distance to the finger changes depending on the irradiation position, and therefore the diameter of the irradiated light beam changes depending on the distance. As a result, the spatial resolution is not constant, and high and low areas may occur. The registration information database 4 stores such information indicating the spatial resolution in association with the registration information.

[0069] Moreover, the matching unit 5 according to the third embodiment includes a weighting unit 501. The weighting unit 501 is configured to be able to perform weighting according to the spatial resolution. For example, the weighting unit 501 may increase the weight of a portion with high spatial resolution and decrease the weight of a portion with low spatial resolution. The distance at which the spatial resolution is high depends on the characteristics of the lens attached to the optical coherence tomography imaging unit 2. For this reason, the weighting unit 501 may store in advance the distance at which the spatial resolution is highest, and determine that a portion close to that distance is a portion with high spatial resolution before performing weighting.

[0070] As a result of weighting by weighting unit 501, matching processing by matching unit 5 is performed in a state where the weight of each part (in other words, the spatial resolution) is taken into consideration. Specifically, parts with large weights (i.e., parts with high spatial resolution) have a larger effect on the matching results, and parts with small weights (i.e., parts with low spatial resolution) have a smaller effect on the matching results.

[0071] (Technical Effects) Next, the technical effects obtained by the optical coherence tomography analysis apparatus 1 according to the third embodiment will be described.

[0072] 12, in the optical coherence tomography analysis apparatus 1 according to the third embodiment, the matching process is performed after weighting according to the spatial resolution. In this way, it is possible to improve the accuracy of the matching process compared to when the matching process is performed without taking the spatial resolution into consideration.

[0073] <Fourth embodiment> An optical coherence tomography analysis apparatus 1 according to a fourth embodiment will be described with reference to Fig. 13. The fourth embodiment differs only in part of the configuration and operation from the first to third embodiments described above, and other parts may be the same as the first to third embodiments. Therefore, the following will describe in detail the parts that differ from the embodiments already described, and will omit a description of other overlapping parts as appropriate.

[0074] (Device configuration) First, the configuration of an optical coherence tomography analysis apparatus 1 according to the fourth embodiment will be described with reference to Fig. 13. Fig. 13 is a block diagram showing the configuration of an optical coherence tomography analysis apparatus according to the fourth embodiment. Note that in Fig. 13, the same elements as those shown in Fig. 3 are denoted by the same reference numerals.

[0075] 13, the optical coherence tomography imaging analysis apparatus 1 according to the fourth embodiment includes an optical coherence tomography imaging unit 2 and an optical coherence tomography analysis unit 3. That is, the optical coherence tomography imaging analysis apparatus 1 according to the fourth embodiment is configured to include the same components as those of the first embodiment (see FIG. 3) described above.

[0076] However, the flattening conversion processing unit 304 according to the fourth embodiment includes a spatial resolution acquisition unit 3041. The spatial resolution acquisition unit 3041 is configured to acquire spatial resolution information indicating the spatial resolution used when acquiring three-dimensional intensity data in the optical coherence tomography imaging unit 2. The spatial resolution information acquired by the spatial resolution acquisition unit 3041 is used for conversion processing in the flattening conversion processing unit 304. Specifically, the flattening conversion processing unit 304 may perform conversion processing using a portion with high spatial resolution as a reference. For example, the flattening conversion processing unit 304 may identify a position in the image with the highest spatial resolution and perform conversion processing such that this portion serves as a reference (i.e., by resetting this portion as the origin). As already described, conversion processing is usually performed based on the epidermis position. However, in the flattening conversion processing unit 304 according to this embodiment, when the spatial resolution at the epidermis position is low, conversion processing may be performed using a portion other than the epidermis position (e.g., the dermis position) as a reference.

[0077] (Technical Effects) Next, the technical effects obtained by the optical coherence tomography analysis apparatus 1 according to the fourth embodiment will be described.

[0078] 13, in the optical coherence tomography analysis apparatus 1 according to the fourth embodiment, the conversion process is performed using a portion with high spatial resolution as a reference. In this way, the portion that serves as a reference for flattening can be accurately identified and the conversion process can be performed, thereby improving the accuracy of the conversion process.

[0079] Fifth Embodiment An optical coherence tomography analysis apparatus 1 according to the fifth embodiment will be described with reference to Fig. 14. The fifth embodiment differs from the first to fourth embodiments described above only in some configurations and operations, and other parts may be the same as the first and fourth embodiments. Therefore, the following will describe in detail the parts that differ from the embodiments already described, and will omit a description of other overlapping parts as appropriate.

[0080] (Device configuration) First, the configuration of an optical coherence tomography analysis apparatus 1 according to the fifth embodiment will be described with reference to Fig. 14. Fig. 14 is a block diagram showing the configuration of an optical coherence tomography analysis apparatus according to the fifth embodiment. Note that in Fig. 14, the same elements as those shown in Fig. 10 are denoted by the same reference numerals.

[0081] 14, the optical coherence tomography analysis apparatus 1 according to the fifth embodiment includes an optical coherence tomography imaging unit 2, an optical coherence tomography analysis unit 3, a registration information database 4, and a matching unit 5. That is, the optical coherence tomography analysis apparatus 1 according to the fifth embodiment is configured to include the same components as those of the second embodiment (see FIG. 10) and the third embodiment (see FIG. 12) described above.

[0082] However, the registration information database 4 according to the fifth embodiment is configured to be able to store three-dimensional data in addition to the registration information (i.e., extracted fingerprint image: two-dimensional data). The three-dimensional data here is three-dimensional data relating to the skin of a living body (e.g., data including the three-dimensional shape of a finger) indicated by three-dimensional brightness data. The three-dimensional data is stored in association with the registration information. The three-dimensional data may be data generated by connecting multiple tomographic images by the tomographic image connection unit 303.

[0083] The registration information and the three-dimensional data stored in the registration information database 4 may each be used for the matching process in the matching unit 5. For example, the matching unit 5 may select either the registration information or the three-dimensional data to perform the matching process. Specifically, when two-dimensional data is acquired as the matching image, the matching unit 5 may use the registration information, which is two-dimensional data, for matching, and when three-dimensional data is acquired as the matching image, the matching unit 5 may use the three-dimensional data for matching.

[0084] Alternatively, the matching unit 5 may perform the matching process using both the registered information and the three-dimensional data. Specifically, the matching unit 5 may determine that the matching is successful when both the registered information and the three-dimensional data match, and may determine that the matching is unsuccessful when either one of them does not match.

[0085] Alternatively, the matching unit 5 may use the three-dimensional data to narrow down the registered information to be matched, and then perform the matching process. For example, the matching unit 5 calculates the distribution of finger curvature and depth obtained from the three-dimensional data stored in the registered information database 4, and compares it with the distribution of finger curvature and depth obtained from the three-dimensional data for matching. If the distribution of finger curvature and depth is significantly different, the matching unit 5 may exclude the registered information linked to that three-dimensional data from the matching target. In other words, the matching process may be performed only on registered information linked to three-dimensional data with a similar distribution of finger curvature and depth.

[0086] (Technical Effects) Next, the technical effects obtained by the optical coherence tomography analysis apparatus 1 according to the fifth embodiment will be described.

[0087] 14, in the optical coherence tomography analysis apparatus 1 according to the fifth embodiment, the registration information database stores two-dimensional data and three-dimensional data. This makes it possible to improve the accuracy and speed of the matching process compared to when the matching process is performed using only two-dimensional data.

[0088] The scope of each embodiment also includes a processing method in which a program that operates the configuration of each embodiment to realize the functions of the above-described embodiments is recorded on a recording medium, the program recorded on the recording medium is read as code, and the program is executed on a computer. In other words, a computer-readable recording medium is also included in the scope of each embodiment. Furthermore, each embodiment includes not only a recording medium on which the above-described program is recorded, but also the program itself.

[0089] Examples of recording media that can be used include floppy disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, magnetic tapes, non-volatile memory cards, and ROMs. Furthermore, the scope of each embodiment is not limited to programs that execute processing by themselves, but also includes programs that execute processing by operating on an OS in cooperation with other software or functions of an expansion board. Furthermore, the program itself may be stored on a server, and part or all of the program may be downloadable from the server to a user terminal.

[0090] <Additional Notes> The above-described embodiment may be further described as follows, but is not limited to the following.

[0091] (Appendix 1) The optical coherence tomography analysis device described in Appendix 1 is an optical coherence tomography analysis device including: an acquisition means that performs optical coherence tomography by irradiating skin with a light beam while scanning it two-dimensionally and acquires three-dimensional brightness data of the skin; a position extraction means that extracts the epidermis position of the skin for each tomographic image obtained by scanning the light beam in the fast axis direction in the three-dimensional brightness data of the skin; a connection means that generates connected three-dimensional data by adjusting the relative positions between the tomographic images and connecting the tomographic images based on the extraction result of the epidermis position of the skin; a flattening means that generates flattened three-dimensional data by performing a conversion process that flattens the epidermis on the connected three-dimensional data based on the extraction result of the epidermis position of the skin; and a pattern extraction means that extracts the skin pattern according to a predetermined extraction depth from the flattened three-dimensional data. is.

[0092] (Appendix 2) The optical coherence tomography analysis device described in Appendix 2 is the optical coherence tomography analysis device described in Appendix 1, further comprising: a storage means for storing the skin pattern extracted by the pattern extraction means as registration information; and a comparison means for performing a comparison process between the newly acquired skin pattern and the registration information stored in the storage means, wherein the storage means stores the registration information in association with transformation parameters related to the conversion process performed by the flattening means, and the comparison means performs the comparison process based on the transformation parameters.

[0093] (Appendix 3) The optical coherence tomography imaging analysis device described in Appendix 3 is the optical coherence tomography imaging analysis device described in Appendix 1 or 2, further comprising: a storage means for storing the skin pattern extracted by the pattern extraction means as registered information; and a matching means for performing a matching process between the newly acquired skin pattern and the registered information stored in the storage means, wherein the matching means performs the matching process by applying weighting according to the spatial resolution when the optical coherence tomography imaging is performed.

[0094] (Appendix 4) The optical coherence tomography imaging analysis device described in Appendix 4 is the optical coherence tomography imaging analysis device described in any one of Appendixes 1 to 3, in which the flattening means performs the conversion processing based on a portion with high spatial resolution when the optical coherence tomography imaging is performed.

[0095] (Appendix 5) The optical coherence tomography analysis device described in Appendix 5 is the optical coherence tomography analysis device described in any one of Appendixes 1 to 4, further comprising: a storage means for storing the skin pattern extracted by the pattern extraction means as registration information; and a matching means for performing a matching process between the newly acquired skin pattern and the registration information stored in the storage means, wherein the storage means stores the registration information and the connected three-dimensional data in association with each other, and the matching means performs the matching process using the connected three-dimensional data in addition to the registration information.

[0096] (Appendix 6) The optical coherence tomography analysis method described in Supplementary Note 6 is an optical coherence tomography analysis method executed by at least one computer, which performs optical coherence tomography by irradiating skin with a light beam while scanning it two-dimensionally, obtains three-dimensional brightness data of the skin, extracts the position of the skin's epidermis for each tomographic image obtained by scanning the light beam in the fast axis direction in the three-dimensional brightness data of the skin, generates connected three-dimensional data by adjusting the relative positions between the tomographic images and connecting the tomographic images based on the extraction result of the skin's epidermis position, performs a conversion process on the connected three-dimensional data to flatten the epidermis based on the extraction result of the skin's epidermis position, generates flattened three-dimensional data, and extracts the skin pattern according to a predetermined extraction depth from the flattened three-dimensional data.

[0097] (Appendix 7) The recording medium described in Appendix 7 is a recording medium having recorded thereon a computer program for causing at least one computer to execute an optical coherence tomography analysis method, the optical coherence tomography method comprising: performing optical coherence tomography by irradiating skin with a light beam while scanning it two-dimensionally; acquiring three-dimensional luminance data of the skin; extracting an epidermis position of the skin for each tomographic image obtained by scanning the light beam in the fast axis direction from the three-dimensional luminance data of the skin; adjusting the relative positions of the tomographic images based on the extraction result of the epidermis position of the skin to connect the tomographic images to generate connected three-dimensional data; performing a conversion process on the connected three-dimensional data to flatten the epidermis based on the extraction result of the epidermis position of the skin to generate flattened three-dimensional data; and extracting the skin pattern according to a predetermined extraction depth from the flattened three-dimensional data.

[0098] (Appendix 8) The computer program described in Supplementary Note 8 causes at least one computer to execute an optical coherence tomography analysis method, which includes performing optical coherence tomography by irradiating skin with a light beam while scanning it two-dimensionally, acquiring three-dimensional brightness data of the skin, extracting an epidermis position of the skin for each tomographic image obtained by scanning the light beam in the fast axis direction from the three-dimensional brightness data of the skin, adjusting relative positions between the tomographic images based on the extraction result of the skin's epidermis position to connect the tomographic images to generate connected three-dimensional data, performing a conversion process on the connected three-dimensional data to flatten the epidermis based on the extraction result of the skin's epidermis position to generate flattened three-dimensional data, and extracting the skin pattern according to a predetermined extraction depth from the flattened three-dimensional data.

[0099] (Appendix 9) The optical coherence tomography analysis system described in Supplementary Note 9 is an optical coherence tomography analysis system including: an acquisition means that performs optical coherence tomography by irradiating skin with a light beam while scanning it two-dimensionally and acquires three-dimensional luminance data of the skin; a position extraction means that extracts an epidermis position of the skin for each tomographic image obtained by scanning the light beam in the fast axis direction in the three-dimensional luminance data of the skin; a connection means that generates connected three-dimensional data by adjusting the relative positions between the tomographic images and connecting the tomographic images based on the extraction result of the epidermis position of the skin; a flattening means that generates flattened three-dimensional data by performing a conversion process that flattenes the epidermis on the connected three-dimensional data based on the extraction result of the epidermis position of the skin; and a pattern extraction means that extracts a pattern of the skin according to a predetermined extraction depth from the flattened three-dimensional data.

[0100] This disclosure may be modified as appropriate within the scope that does not contradict the gist or idea of ​​the invention that can be read from the claims and the entire specification, and optical coherence tomography imaging analysis devices, optical coherence tomography imaging analysis methods, and recording media that incorporate such modifications are also included in the technical idea of ​​this disclosure. [Explanation of symbols]

[0101] 1. Optical coherence tomography imaging analysis device 2 Optical coherence tomography imaging unit 3 Optical Coherence Tomography Analysis Department 4 Registration Information Database 5. Matching section 101 processors 102 memory 103 Communication Interface 104 Input Device 105 Output Device 201 Wavelength Swept Laser Light Source 202 Optical interference and light receiving unit 203 Light beam scanning unit 204 Signal processing and control section 205 Measurement object 211 Circulator 212 Junction 213 Reference beam mirror 214 Balanced Receiver 215 Fiber Collimator 216 Irradiation optical system 301 Three-dimensional brightness data acquisition unit 302 Epidermal position extraction part 303 Tomographic Image Connection 304 Flattening conversion processing unit 305 Fingerprint Image Extraction Unit 501 Weighting section 3041 Spatial resolution acquisition unit

Claims

1. an acquisition means for performing optical coherence tomography imaging by irradiating the skin with a light beam while scanning it two-dimensionally, and acquiring three-dimensional brightness data of the skin; a position extraction means for extracting an epidermis position of the skin for each tomographic image obtained by scanning the light beam in the fast axis direction in the three-dimensional luminance data of the skin; a connecting means for adjusting the relative positions between the tomographic images and connecting the tomographic images based on the extraction result of the epidermis position of the skin, thereby generating connected three-dimensional data; a flattening means for generating flattened three-dimensional data by performing a conversion process for flattening the epidermis on the connected three-dimensional data based on the extracted result of the epidermis position of the skin; a pattern extraction means for extracting a skin pattern corresponding to a predetermined extraction depth from the flattened three-dimensional data; An optical coherence tomography analysis device comprising:

2. a storage means for storing the skin pattern extracted by the pattern extraction means as registration information; a matching means for performing a process of matching the newly acquired skin pattern with the registered information stored in the storage means; Further provided with the storage means stores the registration information in association with a conversion parameter related to the conversion process executed by the flattening means, the matching means executes the matching process based on the transformation parameters; The optical coherence tomography analysis apparatus according to claim 1 .

3. a storage means for storing the skin pattern extracted by the pattern extraction means as registration information; a matching means for performing a process of matching the newly acquired skin pattern with the registered information stored in the storage means; Further provided with the matching unit performs the matching process by weighting the images according to the spatial resolution when the optical coherence tomography imaging is performed. The optical coherence tomography analysis apparatus according to claim 1 or 2.

4. the flattening means performs the conversion process based on a portion with high spatial resolution when the optical coherence tomographic imaging is performed. The optical coherence tomography analysis apparatus according to claim 1 .

5. a storage means for storing the skin pattern extracted by the pattern extraction means as registration information; a matching means for performing a process of matching the newly acquired skin pattern with the registered information stored in the storage means; Further provided with the storage means stores the registration information and the connected three-dimensional data in association with each other; the matching means performs the matching process using the connected three-dimensional data in addition to the registration information; The optical coherence tomography analysis apparatus according to claim 1 .

6. 1. A method of optical coherence tomography analysis executed by at least one computer, comprising: irradiating the skin with a light beam while scanning it two-dimensionally to perform optical coherence tomography imaging, thereby obtaining three-dimensional brightness data of the skin; extracting an epidermis position of the skin for each tomographic image obtained by scanning the light beam in the fast axis direction from the three-dimensional luminance data of the skin; generating connected three-dimensional data by adjusting the relative positions between the tomographic images and connecting the tomographic images based on the extraction result of the epidermis position of the skin; generating flattened three-dimensional data by performing a conversion process for flattening the epidermis on the connected three-dimensional data based on the extraction result of the epidermis position of the skin; extracting the skin pattern according to a predetermined extraction depth from the flattened three-dimensional data; Optical coherence tomography imaging analysis methods.

7. At least one computer irradiating the skin with a light beam while scanning it two-dimensionally to perform optical coherence tomography imaging, thereby obtaining three-dimensional brightness data of the skin; extracting an epidermis position of the skin for each tomographic image obtained by scanning the light beam in the fast axis direction from the three-dimensional luminance data of the skin; generating connected three-dimensional data by adjusting the relative positions between the tomographic images and connecting the tomographic images based on the extraction result of the epidermis position of the skin; generating flattened three-dimensional data by performing a conversion process for flattening the epidermis on the connected three-dimensional data based on the extraction result of the epidermis position of the skin; extracting the skin pattern according to a predetermined extraction depth from the flattened three-dimensional data; A computer program that causes an optical coherence tomography imaging analysis method to be executed.

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