Optical physical unclonable function authentication device and authentication method

Abstract

The invention discloses an optical physical unclonable function authentication device and an authentication method, which are applied to the technical field of optical PUF (Physical Unclonable Function). The first lens is located on the light-emitting side of the light source; the first lens is at least used for expanding light emitted by the light source to a preset area; the optical medium is positioned on the light-emitting side of the first lens; the optical medium has an optical physical unclonable function structure; the second lens is positioned on the light emitting side of the optical medium; the second lens is at least used for splitting the light carrying the optical physical unclonable function information into multiple beams of light; the detector is positioned on the light-emitting side of the second lens; the detection surface of the detector is used for receiving multiple beams of light, and the multiple beams of light form a light spot array with multiple light spots on the detection surface. The light is expanded through the first lens to enable the light to carry more physical unclonable function information, the second lens splits the light into a plurality of light beams, and multiple identity authentication is performed based on a plurality of light spots, so that the safety can be improved.

Description

Technical Field

[0001] This invention relates to the field of optical PUF technology, and in particular to an optically physically unclonable function (OPF) authentication device and an OPF authentication method. Background Technology

[0002] Identity authentication systems based on physically unclonable functions (PUFs) have significant application value in finance, public safety, and defense due to their high security advantages. Among various types of PUFs, optical PUFs are particularly important, renowned for their high security and large capacity of excitation-response pairs. Physically unclonable functions rely on the interaction between light and the microstructure of materials to generate complex modes that are virtually impossible to replicate. These systems utilize properties such as scattering, refraction, polarization, or fluorescence, employing a variety of materials in high-security applications to generate a very large number of excitation-response pairs, resulting in multi-layered enhanced security.

[0003] High-security optical identity authentication systems place high demands on the information capacity and system stability of optical response speckle. Existing optical identity authentication systems generally use divergent laser light sources, and use a small aperture stop (light passage) to intercept the light from the center of the speckle as the excitation source. The excitation speckle is a Gaussian speckle with relatively weak intensity uniformity and a small usable area. After modulation, it interacts with the non-clonal scattering medium, resulting in less information carried by the corresponding optical speckle on the imaging detector. The low utilization rate of the light source makes it difficult to fully realize the high security advantages of optical PUF authentication systems.

[0004] Therefore, how to provide a highly secure optical-physical non-clonable function authentication device is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide an optically physically unclonable function authentication device with higher security and greater information capacity; another purpose of this invention is to provide an optically physically unclonable function authentication method with higher security.

[0006] To address the aforementioned technical problems, this invention provides an optical-physical non-clonable function authentication device, comprising: light source; A first lens located on the light-emitting side of the light source; the first lens is at least used to expand the light emitted by the light source to a predetermined area; An optical medium located on the light-emitting side of the first lens; the optical medium has an optically physically non-clonable function structure; A second lens located on the light-emitting side of the optical medium; the second lens is at least used to split the light beam carrying information about the optical physical non-clonable function into multiple light beams; A detector located on the light-emitting side of the second lens; the detector's detection surface is used to receive multiple beams of light, and the multiple beams of light form a light spot array with multiple light spots on the detection surface, so as to perform multi-identity authentication based on the multiple light spots of the light spot array.

[0007] Optionally, the optical medium includes a liquid crystal cell, which is used to control the light transmittance of multiple pixels according to the encoded information to form a corresponding optically physically non-cloning function structure.

[0008] Optionally, a microlens array is provided on the light-emitting side surface of the liquid crystal cell.

[0009] Optionally, the light source includes a VCSEL laser chip.

[0010] Optionally, the first lens includes a first double freeform lens, the first double freeform lens including a first surface facing the light source and a second surface facing the optical medium; The first surface is used to collimate the light beam; the second surface is used to regulate the light distribution to expand and homogenize the light beam.

[0011] Optionally, the second lens includes a second double freeform lens, the second double freeform lens including a third surface facing the optical medium and a fourth surface facing the detector; The third surface is used to shape the beam into a Gaussian beam array; the fourth surface is used to shape the Gaussian beam array into a beam-splitting array.

[0012] Optionally, the energy distribution of a single spot in the spot array can be any of the following: Point distribution, Gaussian distribution, uniform distribution, Lorentz distribution, Dirac distribution, Bessel beam distribution, ring distribution, pattern distribution; The shape of the light spot can be any of the following: Circle, oval, triangle, rectangle.

[0013] The present invention also provides an optical-physically unclonable function authentication method, applied to any of the optical-physically unclonable function authentication devices described in the present invention, comprising: Acquire multiple speckle images corresponding to the speckle array; Multi-factor authentication is performed based on multiple speckle images.

[0014] Optionally, multi-factor authentication can be performed based on multiple speckle images: Select a speckle image at a preset position from multiple speckle images as the image to be authenticated, and select a total of multiple images to be authenticated; Identity authentication is performed based on each of the images to be authenticated, in order to perform multi-factor authentication.

[0015] Optionally, the optical medium includes a liquid crystal cell, which is used to control the light transmittance of multiple pixels according to the encoding information to form a corresponding optically physically non-cloning function structure; Before acquiring the multiple speckle images corresponding to the speckle array, the process also includes: Obtain user input instructions; Based on the instruction information, corresponding encoding information is generated, and based on the encoding information, the liquid crystal cell is controlled to form a corresponding optical-physical non-cloning function structure, thereby generating a corresponding light spot array.

[0016] The present invention provides an optically physically non-cloning function (OPF) authentication device, comprising: a light source; a first lens located on the light-emitting side of the light source; the first lens being used at least to expand the light emitted from the light source to a preset area; an optical medium located on the light-emitting side of the first lens; the optical medium having an OPF structure; a second lens located on the light-emitting side of the optical medium; the second lens being used at least to split the light carrying OPF information into multiple beams; a detector located on the light-emitting side of the second lens; the detector's detection surface being used to receive the multiple beams of light, the multiple beams of light forming a spot array with multiple spots on the detection surface, and performing multi-identity authentication based on the multiple spots of the spot array.

[0017] Expanding the light beam using a first lens allows it to illuminate a larger area of ​​the optical medium, thus carrying more information about the physically unclonable functions (PFCs). Splitting the light beam into multiple beams using a second lens allows each beam to carry PFC information from a portion of the optical medium. Subsequently, multiple authentication methods based on these multiple light spots can be implemented, significantly improving authentication security.

[0018] This invention also provides a method for authenticating optically physically unclonable functions, which also has the above-mentioned beneficial effects, and will not be elaborated further here. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1This is a schematic diagram of the structure of an optical-physical non-clonable function authentication device provided in an embodiment of the present invention; Figure 2 This is an irradiance distribution diagram of light directly hitting the target surface without passing through the first lens; Figure 3 This is a schematic diagram of the structure of the first lens in this embodiment; Figure 4 This is a radiance distribution diagram of light rays passing through the first lens and illuminating the target surface. Figure 5 This is a diagram showing the effect of the first type of beam splitting; Figure 6 This is a diagram showing the effect of the second type of beam splitting; Figure 7 A flowchart illustrating an optically physically unclonable function authentication method provided in an embodiment of the present invention; Figure 8 This is a flowchart illustrating a specific optical-physical non-clonable function authentication method provided in an embodiment of the present invention.

[0021] In the figure: 1. Light source, 2. First lens, 3. Optical medium, 4. Second lens, 5. Detection surface, 21. First surface, 22. Second surface. Detailed Implementation

[0022] The core of this invention is to provide an optically physically unclonable function (PUF) authentication device. In existing technologies, the light spot formed on the detector surface can only carry a small portion of the information from the optical PUFs, resulting in low authentication security.

[0023] The present invention provides an optically physically non-clonable function (OPF) authentication device, comprising: a light source; a first lens located on the light-emitting side of the light source; the first lens being used at least to expand the light emitted from the light source to a preset area; an optical medium located on the light-emitting side of the first lens; the optical medium having an OPF structure; a second lens located on the light-emitting side of the optical medium; the second lens being used at least to split the light carrying OPF information into multiple beams; a detector located on the light-emitting side of the second lens; the detector's detection surface being used to receive multiple beams of light, the multiple beams of light forming a spot array with multiple spots on the detection surface, and performing multi-identity authentication based on the multiple spots of the spot array.

[0024] Expanding the light beam using a first lens allows it to illuminate a larger area of ​​the optical medium, thus carrying more information about the physically unclonable functions (PFCs). Splitting the light beam into multiple beams using a second lens allows each beam to carry PFC information from a portion of the optical medium. Subsequently, multiple authentication methods based on these multiple light spots can be implemented, significantly improving authentication security.

[0025] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example

[0026] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of an optical-physical non-clonable function authentication device provided in an embodiment of the present invention.

[0027] See Figure 1 In this embodiment, the optically physically non-cloning function (OPF) authentication device includes: a light source 1; a first lens 2 located on the light-emitting side of the light source 1; the first lens 2 being used at least to expand the light emitted by the light source 1 to a preset area; an optical medium 3 located on the light-emitting side of the first lens 2; the optical medium 3 having an OPF structure; a second lens 4 located on the light-emitting side of the optical medium 3; the second lens 4 being used at least to split the light carrying OPF information into multiple beams; a detector located on the light-emitting side of the second lens 4; the detector's detection surface 5 being used to receive the multiple beams of light, and the multiple beams of light forming a spot array with multiple spots on the detection surface 5, so as to perform multi-identity authentication based on the multiple spots of the spot array.

[0028] The aforementioned light source 1 is typically a laser light source 1. The light emitted by it passes through the optical medium 3, carrying optically physically non-cloning function (OPF) information, which can ultimately be used for authentication. In this embodiment, the light source 1 may include a VCSEL (Vertical-Cavity Surface-Emitting Laser) chip. The wavelength range of the emitted beam is typically 380nm-1500nm. The VCSEL chip can emit a Gaussian-distributed circular or square beam, which facilitates beam expansion and shaping by the second lens 4. Of course, other light source structures 1 can also be used in this embodiment, and no specific limitation is made here.

[0029] In this embodiment, the light emitted from the light source 1 passes through the first lens 2. The first lens 2 is used at least to expand the light beam, that is, to expand the light emitted from the light source 1 to a preset area. By using the first lens 2, the area of ​​the light that ultimately illuminates the optical medium 3 can be increased, thereby allowing the light passing through the optical medium 3 to carry more optically physics-unclonable function information. In addition to its beam-expanding function, the first lens 2 may also have other functions, such as homogenizing and shaping the light, the details of which will be described in detail in the following embodiments.

[0030] In this embodiment, the light shaped by the first lens 2 illuminates the optical medium 3. The optical medium 3 has a physically non-clonable function (PUF) structure and is translucent, allowing it to modulate the passing light. The light passing through the optical medium 3 can carry PUF information. The optical medium 3 can be a sheet structure with a fixed PUF structure or a sheet structure with a variable PUF structure, such as a liquid crystal cell. Specific details will be provided in the following embodiments.

[0031] In this embodiment, the light modulated by the optical medium 3 passes through the second lens 4. The second lens 4 is used to split the light carrying optically physically unclonable (OPI) information into multiple beams. Each beam can carry at least some OPI information corresponding to a portion of the OPI structure in the optical medium 3. Typically, the OPI information carried by each beam corresponds to the OPI structure of a certain region of the optical medium 3 at the beam's location. It should be noted that in this embodiment, since the light beam is expanded by the first lens 2, the second lens 4 can be used to split the light beam into multiple beams.

[0032] In this embodiment, the multiple beams of light split by the second lens 4 will eventually illuminate the detection surface 5 of the detector. That is, the detection surface 5 of the detector is used to receive the multiple beams of light. The multiple beams of light can form multiple light spots on the detection surface 5. Typically, each beam of light can form a corresponding light spot on the detection surface 5. Multiple light spots can form a light spot array. In this embodiment, multiple identity authentication can be performed based on the multiple light spots of the above-mentioned light spot array.

[0033] Multi-identity authentication refers to performing multiple authentications. In this embodiment, authentication can be performed once based on a single light spot, while multiple light spots based on an array of light spots can perform multiple different authentications, thus achieving multi-identity authentication. It should be noted that when performing multi-identity authentication, all light spots can be used, or only some light spots can be selectively used. This selection process can increase the randomness of the entire multi-identity authentication process. In this embodiment, each authentication can be performed using a single light spot or a pattern composed of multiple light spots. The pattern composed of multiple light spots essentially includes the positional relationship between the multiple light spots and can itself serve as information referenced during authentication.

[0034] The aforementioned detector can specifically be a CCD (Charge-Coupled Device) imaging device. The size of the detection surface 5 of this CCD imaging device is typically not smaller than the size of the optical medium 3, to ensure that it can receive light carrying information about the optically physically non-clonable functions corresponding to each region of the optical medium 3. Of course, the specific structure of the detector can be set according to the actual situation, and no specific limitation is made here.

[0035] This embodiment provides an optical physical non-cloning function (PNF) authentication device. A first lens 2 expands the light beam, allowing it to illuminate a larger area of ​​the optical medium 3, thus carrying more PNF information. A second lens 4 splits the light beam into multiple beams, ensuring each beam carries PNF information from a portion of the optical medium 3. This allows for multiple authentication methods based on the multiple light spots, significantly improving authentication security.

[0036] The specific details of the optical-physical non-clonable function authentication device provided by the present invention will be described in detail in the following embodiments. Example

[0037] Please refer to Figures 2 to 7 , Figure 2 This is an irradiance distribution diagram of light directly hitting the target surface without passing through the first lens; Figure 3 This is a schematic diagram of the structure of the first lens in this embodiment; Figure 4 This is a radiance distribution diagram of light rays passing through the first lens and illuminating the target surface. Figure 5 This is a diagram showing the effect of the first type of beam splitting; Figure 6 This is a diagram showing the effect of the second type of beam splitting.

[0038] Unlike the above embodiments, this embodiment further defines the specific structure of each component in the optical-physical non-clonable function authentication device based on the above embodiments. The rest has been described in detail in the above embodiments and will not be repeated here.

[0039] See Figure 1 In this embodiment, the optical medium 3 includes a liquid crystal cell, which is used to control the light transmittance of multiple pixels according to encoded information to form a corresponding optically physically non-cloning function (OPF) structure. Multiple pixels are arranged in an array within the liquid crystal cell. The specific structure of the liquid crystal cell can be found in existing technology and will not be described in detail here. This embodiment focuses on controlling the light transmittance of each pixel in the liquid crystal cell. Based on the pattern formed by pixels with different light transmittances, a corresponding OPF structure can be formed. Accordingly, in this embodiment, the liquid crystal cell is specifically used to control the light transmittance of multiple pixels according to encoded information to form a corresponding OPF structure. The encoded information is the instruction information received by the liquid crystal cell. The specific content of this encoded information can correspond to the operator's identity information, etc., and is not specifically limited here.

[0040] Preferably, in this embodiment, a microlens array is provided on the light-emitting side surface of the liquid crystal cell. Specifically, the microlens array is disposed on the light-emitting side surface of the liquid crystal cell, and typically consists of multiple microlenses arranged in an array. These microlenses can refract light rays coupled from the liquid crystal cell, thereby increasing the randomness of the light rays coupled from the liquid crystal cell based on the distribution of the microlenses, thus increasing the randomness of the optically physical non-cloning function structure.

[0041] Furthermore, in this embodiment, the microlens array is a microlens array including micro / nano particles, meaning that each microlens in the array can have micro / nano particles. By incorporating micro / nano particles into the microlens array, and based on the refraction or reflection of light by these particles, as well as the randomness of their positions within the microlenses, the randomness of the optically physically unclonable function (OPF) structure provided by the liquid crystal cell can be further increased. Combined with this embodiment, the light transmittance of each pixel in the liquid crystal cell can be actively controlled. Even using the same encoding information, different OPF structures can be generated for different liquid crystal cells, ensuring the reliability of the final authentication.

[0042] In this embodiment, the first lens 2 includes a first double freeform surface lens, which includes a first surface 21 facing the light source 1 and a second surface 22 facing the optical medium 3; the first surface 21 is used to collimate the light beam; the second surface 22 is used to regulate the light distribution to expand and homogenize the light beam.

[0043] The first lens 2 described above can be a double freeform surface lens. In this embodiment, different functions can be achieved based on the two curved surfaces of the double freeform surface lens. Specifically, the surface of the first double freeform surface lens facing the light source 1 is the first surface 21, and the surface facing the optical medium 3 is the second surface 22. The first surface 21 can be an aspherical surface, used to collimate the Gaussian beam emitted by the VCSEL chip. The second surface 22 is typically a freeform surface, specifically used to control the light distribution, thereby achieving beam expansion and homogenization. In this embodiment, the preset exit angle range of the light passing through the second surface 22 is 10° to 130°, including the endpoint value.

[0044] Specifically, in this embodiment, the divergence angle of the VCSEL chip serving as light source 1 can be set to 8°, the beam waist to 0.1mm, and the aperture of the first double freeform lens to be square with a side length of 3.6mm. The lens is made of PMMA (Polymethyl Methacrylate) with a refractive index n of 1.49. The distance between the first double freeform lens and the target plane is 30mm, and the target plane is 10mm × 10mm in size. This target plane can be the plane where the optical medium 3 is located. The beam emitted from the VCSEL chip is directly emitted onto the target plane without being collimated or shaped by the first double freeform lens, resulting in the following irradiance distribution pattern: Figure 2 As shown, the irradiance uniformity is only 52.7%.

[0045] See Figure 3 After passing through the first double freeform lens (the first surface 21 being aspherical and the second surface 22 being an optimized freeform surface), the irradiance distribution of the beam emitted from the VCSEL chip reaching the target surface after passing through the first double freeform lens is shown in the figure below. Figure 4 As shown, the irradiance uniformity of the 10mm×10mm target surface reached 92.8%.

[0046] In this embodiment, the second lens 4 includes a second double freeform surface lens, which includes a third surface facing the optical medium 3 and a fourth surface facing the detector; the third surface is used to shape the beam into a Gaussian beam array; the fourth surface is used to shape the Gaussian beam array into a beam-splitting array.

[0047] The second lens 4 mentioned above can also be a double freeform surface lens. In this embodiment, different functions can be achieved based on the two surfaces of the double freeform surface lens. Specifically, the surface of the second double freeform surface lens facing the optical medium 3 is the third surface, and the surface facing the detector is the fourth surface. The third surface can be a continuous and smooth freeform surface, while the fourth surface can be a continuous freeform surface with some rough areas. The cooperation between the third and fourth surfaces can achieve synchronous and precise control of the beam energy and wavefront.

[0048] Specifically, in this embodiment, the third surface is used to shape the light beam into a Gaussian beam array. That is, the light beam modulated by the liquid crystal cell can be shaped into an approximate Gaussian beam array after passing through the third surface. This approximate Gaussian beam array can then be shaped into a beam-splitting array after passing through the fourth surface. This beam-splitting array forms a spot array on the detector surface 5. The aforementioned second freeform surface lens can achieve synchronous control of the beam wavefront and illuminance. When designing the second double freeform surface lens, the fourth surface is specifically calculated based on the optical path equality condition of the optical system, and its concavity and convexity properties also depend entirely on this calculation result. After determining the surface shape data of the third surface, solving the corresponding equations yields the surface shape data related to the fourth surface.

[0049] Specifically, in this embodiment, the energy distribution of a single light spot in the light spot array can be any of the following: point distribution, Gaussian distribution, uniform distribution, Lorentz distribution, Dirac distribution, Bessel beam distribution, annular distribution, or patterned distribution; the shape of the light spot can be any of the following: circular, elliptical, triangular, or rectangular. The energy distribution and shape of the single light spot can be achieved by designing the structures of the first lens 2 and the second lens 4 accordingly, and will not be elaborated further here.

[0050] In this embodiment, the aforementioned second double freeform lens can split the Gaussian point light source 1 (the optical fiber emitted by the VCSEL chip) with a spherical wavefront into a 5×5 rectangular uniform light spot array on the detection surface 5, where each light spot in the array has the same size and energy. Let the wavelength of light source 1 be 680nm and the divergence angle be θ. x_half =θ y_half =12.5°. When the distance between the first surface 21 of the first double freeform lens and the light source 1 is 3mm, and the distance between the second surface 22 and the light source 1 is 8mm, the target surface (liquid crystal cell) can be located at a distance of 10mm from the light source 1. At this time, the side length of the beam-expanding spot on the target surface can be 6mm. The spot area is 2.33 times that without the first freeform lens.

[0051] Assume light source 1 has a wavelength of 680 nm and a divergence angle of θ. x_half =θ y_half=10.5°. The distance between the first surface 21 of the first double freeform lens and the light source 1 is 3mm, the distance between the second surface 22 and the light source 1 is 8mm, and the distance between the target surface (liquid crystal cell) and the light source 1 can be 10mm. At this time, the side length of the beam-expanding spot on the target surface can be 5mm. The spot area is 2.56 times that without the first freeform lens.

[0052] Assume a Gaussian beam (spot side length 5mm) is emitted from light source 1 located at z=0 (the exit surface of the liquid crystal cell). Light source 1 has a wavelength of 680nm, and the beam propagates along the positive z-axis. The third surface of the second double freeform lens is located at z=35mm, the fourth surface at z=80mm, and the detector surface 5 is located at z=165mm. The size of a single spot on detector surface 5 can be a rectangular spot of 0.21mm × 0.11mm. The beam splitting effect on detector surface 5 is as follows: Figure 5 As shown.

[0053] In this embodiment, by designing different surface morphologies of the second double freeform lens, a rectangular light spot with a side length of 0.22 mm can be formed on the detection target surface. The beam splitting effect on the detection surface 5 is shown in [the figure]. Figure 6 As shown.

[0054] In this embodiment, when fabricating the optical-physical non-cloning function (OPF) authentication device, two freeform surface lenses can be connected together via a fixed substrate. The purpose is to form a freeform surface lens array from multiple lenses, facilitating subsequent assembly and adjustment. The substrate can be made of the same material as the freeform surface lenses. During manufacturing, multiple freeform surface lenses and the substrate can be injection molded together. The substrate does not control the light distribution; it is merely a connector. The thickness of the substrate needs to be less than the edge thickness of the freeform surface lenses to avoid affecting the surface shape of the lenses.

[0055] In this embodiment, the first and second double freeform lenses can be injection molded or glass-molded from a light-transmitting adhesive with a light transmittance greater than 90%. The material of the light-transmitting adhesive is any one of the following: PC, PMMA, epoxy, silicone resin, or silicone, and its refractive index is typically greater than 1.4. The glass material is typically inorganic glass or chalcogenide glass.

[0056] The first distance from the liquid crystal cell to the light source 1 ranges from 10mm to 50mm, including the endpoint values. Characteristic values ​​for this first distance include 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, and 50mm. The second distance from the detection surface 5 to the liquid crystal cell ranges from 50mm to 200mm, including the endpoint values. Characteristic values ​​for this second distance include 50mm, 80mm, 100mm, 120mm, 150mm, 160mm, 180mm, and 200mm.

[0057] This embodiment provides an optical physical non-cloning function (PNF) authentication device. A first lens 2 expands the light beam, allowing it to illuminate a larger area of ​​the optical medium 3, thus carrying more PNF information. A second lens 4 splits the light beam into multiple beams, ensuring each beam carries PNF information from a portion of the optical medium 3. This allows for multiple authentication methods based on the multiple light spots, significantly improving authentication security.

[0058] The specific authentication process will be described in detail in the following examples, and will not be repeated here. Example

[0059] This embodiment further describes the optically physically unclonable function (OPF) authentication method based on the above embodiments. The specific structure of the OPF authentication device has been described in detail in the above embodiments and will not be repeated here.

[0060] See Figure 7 , Figure 7 This is a flowchart of an optical-physical non-clonable function authentication method provided in an embodiment of the present invention.

[0061] See Figure 7 In this embodiment, the optical-physically unclonable function authentication method is applied to the optical-physically unclonable function authentication device described in any of the above embodiments, including: S101: Acquire multiple speckle images corresponding to the speckle array.

[0062] Prior to this step, the light source 1 can be controlled to generate corresponding light rays, which will pass through the first lens 2, the optical medium 3 and the second lens 4 in sequence to reach the detection surface 5, and form a light spot array with multiple light spots on the detection surface 5. Each light spot in the light spot array has optically physically unclonable function information corresponding to a portion of the optical medium 3.

[0063] S102: Multi-identity authentication based on multiple speckle images.

[0064] In this embodiment, the speckle image can be a pattern illuminated by a single light spot or a combination of patterns illuminated by multiple light spots. The correspondence between the speckle image and the number of light spots is not specifically limited in this embodiment. Typically, the pattern illuminated by each light spot is a speckle image.

[0065] In this step, authentication can be performed once for each speckle image. The authentication process typically involves determining whether the acquired speckle image matches a pre-stored speckle image in the database. If the acquired speckle image matches the stored speckle image, the authentication is successful. Conversely, if the acquired speckle image does not match the stored speckle image, the authentication fails.

[0066] In this step, multiple identity authentications can be performed using multiple speckle images, thus achieving multi-factor authentication.

[0067] This embodiment provides an optical physical non-cloning function (PNF) authentication method. By using a first lens 2 to expand the light beam, the light can illuminate a larger area of ​​the optical medium 3, thus carrying more PNF information. A second lens 4 splits the light beam into multiple beams, allowing each beam to carry PNF information from a portion of the optical medium 3. Subsequently, multiple authentication methods based on these multiple light spots can be performed, significantly improving authentication security.

[0068] The specific details of this invention will be described in detail in the following embodiments, and will not be repeated here. Example

[0069] Please refer to Figure 8 , Figure 8 This is a flowchart illustrating a specific optical-physical non-clonable function authentication method provided in an embodiment of the present invention.

[0070] In this embodiment, a liquid crystal cell is specifically selected as the optical medium 3. That is, the optical medium 3 includes a liquid crystal cell, which is used to control the light transmittance of multiple pixels according to encoded information to form a corresponding optically physically non-cloning function structure. See also... Figure 8 In this embodiment, the optical-physical non-cloning function authentication method includes: S201: Obtain user-input command information.

[0071] This instruction information is typically entered by the user who needs to authenticate. The specific content of this instruction information can be set according to the actual situation and is not specifically limited here. For example, it can be the corresponding instruction information such as a PIN code or password entered by the user.

[0072] S202: Generate corresponding encoding information according to the instruction information, control the liquid crystal cell to form the corresponding optical-physical non-cloning function structure according to the encoding information, and generate the corresponding light spot array.

[0073] In this embodiment, after receiving the aforementioned instruction information, the processor generates corresponding encoded information. This encoded information is recognizable by the liquid crystal cell and is used to control the light transmittance of each pixel in the liquid crystal cell. Based on specific encoded information, the processor can control the light transmittance of the pixel corresponding to that encoded information while controlling the opacity of other pixels, thereby generating a corresponding optically physically unclonable function (OFC) structure. In this embodiment, depending on the different encoded information, the same liquid crystal cell can also exhibit different OFC structures for authentication.

[0074] After controlling the liquid crystal cell to form the corresponding optically physically non-cloning function (OFLAC) structure, the light source 1 can be controlled to emit light, ultimately generating a corresponding light spot array on the detector surface 5. Each light spot in this array thus possesses corresponding OFLAC information. This embodiment, based on the programmable partitioning control of the liquid crystal cell to control the phase distribution of the light field in each region, can achieve high flexibility and high security in generating OFLAC structures.

[0075] S203: Acquire multiple speckle images corresponding to the speckle array.

[0076] This step is basically the same as S101 in the above embodiment. For details, please refer to the above embodiment. It will not be repeated here.

[0077] Specifically, in this step, to suppress temperature drift and vibration interference and ensure stable operation of identity authentication, the original speckle image corresponding to the speckle array can be processed to obtain the speckle image used in the actual identity authentication process. Specifically, to suppress temperature drift and vibration interference, multiple consecutive frames of original speckle images are first acquired by the detector. Then, based on these multiple frames, the average brightness of each pixel at the same position is calculated. This average brightness is used as the brightness value of the corresponding pixel in the speckle image used in the actual identity authentication process, thereby suppressing temperature drift and vibration interference.

[0078] Accordingly, in this embodiment, when calculating the brightness value of a target pixel in the speckle image used in the actual identity authentication process, the brightness of the original pixel in the original speckle image corresponding to the target pixel, and the brightness of the four or eight pixels surrounding the original pixel, can be averaged or weighted to obtain the brightness value of the corresponding target pixel. By calculating the average or weighted average of a certain original pixel and its surrounding pixels in the original image as the brightness value of the target pixel in the speckle image used in the actual identity authentication process, temperature drift and vibration interference can be suppressed.

[0079] It should also be noted that the two methods described above can be used simultaneously. For example, the brightness values ​​of pixels at the same position can be determined first using multiple frames of original speckle images as the first speckle image. Then, the average brightness value of a pixel and its surrounding pixels in the first speckle image can be calculated as the brightness value of the pixel at the center position in the second speckle image. This second speckle image can then be used for multi-factor authentication in subsequent steps. In this embodiment, the method for generating the speckle image can also be used independently, and no specific limitation is made here.

[0080] S204: Select a speckle image at a preset position from multiple speckle images as the image to be authenticated, and select multiple images to be authenticated in total.

[0081] In this embodiment, to speed up the verification process, a speckle image at a preset position can be selected from multiple speckle images as the image to be authenticated. Multiple images need to be selected in this step, and subsequent identity authentication will be based on these images. It should be noted that if the process of selecting the image to be authenticated is implemented using a random algorithm, the randomness can be further increased to improve the accuracy of identity authentication.

[0082] For example, in this embodiment, the spatial position of each light spot can be generated by a pseudo-random sequence or a chaotic mapping algorithm to ensure that each user's authentication pattern is unique and unpredictable. The distribution pattern of each light spot can adopt a quasi-random gridded layout (such as low-difference sequence sampling) to avoid periodic structures while ensuring uniform coverage and enhancing anti-spoofing capabilities.

[0083] In this embodiment, the number of light spots used for identity authentication is related to the security level of the authentication. Obviously, the more light spots used for identity authentication, the higher the security, but the longer the authentication time. The selection principle for the number of light spots for a single authentication in this embodiment is shown in Table 1 below: Table 1. Principles for Selecting the Number of Spots in a Single Authentication Session In this embodiment, the number of light spots is selected based on statistical security assessment. Too few light spots make it vulnerable to brute-force attacks, while too many increase the time required for interferogram acquisition and matching. Typically, 15 light spots offer a good balance between response speed (<0.5s) and security (FAR<10⁻). 5 To achieve the optimal balance between )

[0084] S205: Perform identity authentication based on each image to be authenticated in order to conduct multi-factor authentication.

[0085] In this step, identity authentication is performed based on each image to be authenticated. Specifically, digital correlation algorithms, such as normalized cross-correlation or raster image feature matching, are used to match the image to be authenticated with images pre-stored in the database. When a match is successful, it means that identity authentication is successful. Identity authentication can be performed once based on each image to be authenticated, and multiple rounds of identity authentication can be achieved based on multiple images to be authenticated.

[0086] Specifically, when the matching degree of multiple identity authentications all meets the threshold requirements, the user is determined to be a legitimate user and corresponding permissions are granted according to the password level.

[0087] The optically physically unclonable function (PUF) authentication method provided in this embodiment utilizes the nonlinear chaotic characteristics of speckle and the physical unclonability (PUF) to prevent deep learning models from being forged through generalization of training samples, thus providing high security.

[0088] In this embodiment, a microlens array can be disposed on the light-emitting side surface of the liquid crystal cell, and the specific fabrication method of the microlens array includes: S301: Spin-coating the first sol-gel layer onto the light-emitting side surface of the liquid crystal cell.

[0089] S302: Based on the first sol-gel layer, the microlens template is pressed together, so that the first sol-gel layer overflows into the microlens template and is disposed in the microlens groove facing the first sol-gel layer. The shape of the microlens groove corresponds to each microlens of the microlens array.

[0090] S303: After pressing the microlens template, the first sol-gel layer is cured to form the microlens array.

[0091] Specifically, in this embodiment, the first sol-gel layer can be a sol-gel photosensitive layer containing micro- and nano-particles; correspondingly, the above-mentioned process of curing the first sol-gel layer includes: after pressing the microlens template, exposing the sol-gel photosensitive layer containing micro- and nano-particles to convert the sol-gel photosensitive layer containing micro- and nano-particles into a glassy state; and peeling off the microlens template after exposing the sol-gel photosensitive layer containing micro- and nano-particles to form a microlens array.

[0092] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section.

[0093] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0094] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0095] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0096] The foregoing has provided a detailed description of the optical-physical non-clonable function authentication device and method provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A device for authenticating optically physically unclonable functions, characterized in that, include: light source; The first lens is located on the light-emitting side of the light source; The first lens is used at least to expand the light emitted by the light source to a predetermined area; The optical medium located on the light-emitting side of the first lens; The optical medium has an optically physically non-clonable function structure; A second lens located on the light-emitting side of the optical medium; the second lens is at least used to split the light beam carrying information about the optical physical non-clonable function into multiple light beams; A detector located on the light-emitting side of the second lens; the detector's detection surface is used to receive multiple beams of light, and the multiple beams of light form a light spot array with multiple light spots on the detection surface, so as to perform multi-identity authentication based on the multiple light spots of the light spot array.

2. The optical-physical non-clonable function authentication device according to claim 1, characterized in that, The optical medium includes a liquid crystal cell, which is used to control the light transmittance of multiple pixels according to the encoded information to form a corresponding optically physically non-clonable function structure.

3. The optical-physical non-clonable function authentication device according to claim 2, characterized in that, A microlens array is provided on the light-emitting side surface of the liquid crystal cell.

4. The optical-physical non-clonable function authentication device according to claim 1, characterized in that, The light source includes a VCSEL laser chip.

5. The optical-physical non-clonable function authentication device according to claim 1, characterized in that, The first lens includes a first double freeform lens, which includes a first surface facing the light source and a second surface facing the optical medium; The first surface is used to collimate the light beam; the second surface is used to regulate the light distribution to expand and homogenize the light beam.

6. The optical-physical non-clonable function authentication device according to claim 1, characterized in that, The second lens includes a second double freeform lens, which includes a third surface facing the optical medium and a fourth surface facing the detector; The third surface is used to shape the beam into a Gaussian beam array; the fourth surface is used to shape the Gaussian beam array into a beam-splitting array.

7. The optical-physical non-clonable function authentication device according to claim 1, characterized in that, The energy distribution of a single spot in the spot array is any one of the following: Point distribution, Gaussian distribution, uniform distribution, Lorentz distribution, Dirac distribution, Bessel beam distribution, ring distribution, pattern distribution; The shape of the light spot can be any of the following: Circle, oval, triangle, rectangle.

8. A method for authenticating optically physically unclonable functions, characterized in that, The optical-physical non-clonable function authentication apparatus according to any one of claims 1 to 7 comprises: Acquire multiple speckle images corresponding to the speckle array; Multi-factor authentication is performed based on multiple speckle images.

9. The method according to claim 8, characterized in that, Multi-factor authentication based on multiple speckle images: Select a speckle image at a preset position from multiple speckle images as the image to be authenticated, and select a total of multiple images to be authenticated; Identity authentication is performed based on each of the images to be authenticated, in order to perform multi-factor authentication.

10. The method according to claim 8, characterized in that, The optical medium includes a liquid crystal cell, which is used to control the light transmittance of multiple pixels according to the encoded information to form a corresponding optically physically non-clonable function structure. Before acquiring the multiple speckle images corresponding to the speckle array, the process also includes: Obtain user input instructions; Based on the instruction information, corresponding encoding information is generated, and based on the encoding information, the liquid crystal cell is controlled to form a corresponding optical-physical non-cloning function structure, thereby generating a corresponding light spot array.

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