Periscopic palm vein recognition method and intelligent door lock

Abstract

The invention discloses a periscopic palm vein recognition method and an intelligent door lock, and the method comprises the steps: when a palm is placed in an area of a glass panel, a near-infrared light source emits infrared rays to the palm of a user; the reflecting mirror intensively guides infrared rays reflected by the palm to the imaging lens group; the imaging lens group optimizes the infrared light signal to obtain an optimized infrared light signal, and focuses the optimized infrared light signal to the image sensor; the image sensor converts the optimized infrared light signal into a digital image signal and sends the digital image signal to the control processing unit; and the control processing unit converts the digital image signal into a palm vein dark fringe image, extracts a palm vein feature value from the palm vein dark fringe image, and controls unlocking if the palm vein feature value exists in the memory. Through the periscopic optical structure design, ultra-short-distance high-quality palm vein imaging is achieved, a user does not need to adjust the hand position and distance deliberately, identity recognition can be completed only by naturally holding the door handle, operation is convenient, and the recognition success rate is high.

Description

Technical Field

[0001] This invention relates to the field of smart door lock recognition technology, and in particular to a periscope palm vein recognition method and a smart door lock. Background Technology

[0002] In the field of smart locks, biometric technology has been widely used, mainly including fingerprint recognition, facial recognition, and password recognition. Fingerprint locks dominate due to their mature technology and relatively low cost, but they suffer from problems such as fingerprint wear and failure to recognize fingerprints when hands are wet. While facial recognition locks are convenient to use, they pose a risk of privacy breaches and are easily affected by factors such as lighting and angle.

[0003] Palm vein recognition technology, as an emerging biometric technology, has received widespread attention in the field of security authentication in recent years. This technology uses near-infrared light to illuminate the palm, utilizing the absorption characteristics of subcutaneous veins in the palm to acquire vein images. Because the distribution of veins is unique to each person, high-precision identity verification can be achieved. Compared with traditional fingerprint and facial recognition, palm vein recognition has advantages such as strong anti-counterfeiting capabilities and high security.

[0004] Currently, most palm vein recognition devices on the market use a direct-light optical structure, meaning the near-infrared light source and image sensor are directly aimed at the palm area being recognized. The optical system of these devices typically uses a fixed-focal-length lens assembly, with a fixed imaging distance and field of view, usually between 15-30 centimeters. When the user's palm is too close to the device, it exceeds the lens's depth of field, resulting in a blurred image; when the distance is too far, the palm occupies too small a proportion in the image, making it impossible to obtain sufficient vein feature information. This structure requires the user to place their palm within a specific distance in front of the device, requiring a certain amount of learning and adaptation for correct use, resulting in a relatively poor user experience.

[0005] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0006] The main objective of this invention is to provide a periscope palm vein recognition method and a smart door lock, aiming to solve the problem that in the prior art, when recognizing palm veins in smart door locks, users need to place their palms within a specific distance range. Too large or too small a distance will lead to recognition difficulties and low recognition success rate.

[0007] To achieve the above objectives, the present invention provides a periscope palm vein recognition method, which is applied to a smart door lock. The smart door lock includes a lock shell with a glass panel, a periscope optical module including a near-infrared light source, a reflector, an imaging lens group, and an image sensor, and a control processing unit; the periscope palm vein recognition method includes: When the user's palm is detected to be placed in the area of ​​the glass panel, infrared rays are emitted to the user's palm through the near-infrared light source; The infrared light reflected from the palm is concentrated and guided to the imaging lens group by the reflector. An optimized infrared light signal is obtained by optimizing the infrared light signal transmitted by the reflector through the imaging lens group, and the optimized infrared light signal is focused onto the image sensor; The optimized infrared light signal is converted into a digital image signal by the image sensor, and the digital image signal is sent to the control processing unit. The control processing unit converts the digital image signal into a palm vein dark pattern image, extracts palm vein feature values ​​from the palm vein dark pattern image, verifies whether the palm vein feature values ​​exist in the memory, and if they exist, controls the smart door lock to unlock based on the successful verification result.

[0008] Optionally, in the periscope palm vein recognition method, when the user's palm is detected to be placed in the area of ​​the glass panel, emitting infrared light to the user's palm via the near-infrared light source specifically includes: A near-infrared LED array with a wavelength of 700-1100nm is used, and the near-infrared LED array is evenly distributed around the glass panel; When the near-infrared LED array detects that the user's palm is placed in the area of ​​the glass panel, it emits infrared rays to the vein area inside the user's palm.

[0009] Optionally, in the periscope palm vein recognition method, the step of concentrating and guiding the infrared light reflected from the palm through the reflector to the imaging lens group specifically includes: High-reflectivity plane mirrors or slightly curved mirrors are used as reflectors and placed at a preset angle; When infrared light reflected from the palm is transmitted to the reflector, the reflector optimizes the infrared light path transmission and concentrates the infrared light to the imaging lens group.

[0010] Optionally, in the periscope palm vein recognition method, the step of optimizing the infrared light signal transmitted by the reflector through the imaging lens group to obtain an optimized infrared light signal, and focusing the optimized infrared light signal onto the image sensor, specifically includes: Multiple lenses are combined to form an imaging lens group, which optimizes the infrared light signal transmitted by the reflector, cancels optical distortion, controls the shape and proportion of the dark vein pattern to be consistent with the actual vein distribution, filters out invalid stray light, and obtains an optimized infrared light signal. The imaging lens group focuses the obtained optimized infrared light signal onto the image sensor.

[0011] Optionally, the periscope palm vein recognition method, wherein converting the optimized infrared light signal into a digital image signal using the image sensor and sending the digital image signal to the control processing unit specifically includes: The image sensor surface is covered with a photodiode array. When infrared reflected light from the imaging lens group shines on the image sensor, the photodiode array uses the photoelectric effect to convert the difference in light signals between the palm vein area and the background tissue into corresponding weak current signals. The transistor integrated in the image sensor directly amplifies the current signal at the detection point, and then the amplified analog electrical signal is converted into a digital image signal by an on-chip analog-to-digital converter.

[0012] Optionally, the periscope-type palm vein recognition method, wherein the step of converting the digital image signal into a palm vein dark pattern image by the control processing unit, extracting palm vein feature values ​​from the palm vein dark pattern image, verifying whether the palm vein feature values ​​exist in the memory, and if they exist, controlling the smart door lock to unlock based on the successful verification result, specifically includes: The microprocessor of the control processing unit converts the digital image signal into a palm vein dark pattern image; The palm vein feature values ​​of the selected user are pre-stored in the memory of the control processing unit; The recognition algorithm module of the control processing unit extracts palm vein feature values ​​from the palm vein dark pattern image and verifies whether the palm vein feature values ​​exist in the memory. If the palm vein feature value exists in the memory, the microprocessor sends the successful verification result to the drive circuit of the smart door lock; The driven circuit controls the motor drive module and the lock cylinder drive mechanism to perform the unlocking operation based on the successful verification result.

[0013] In addition, to achieve the above objectives, the present invention also provides a smart door lock, which includes: a door lock shell, a periscope optical module, and a control processing unit; the smart door lock is used to implement the periscope palm vein recognition method.

[0014] Optionally, in the smart lock, the lock housing is provided with a glass panel, and the area of ​​the glass panel is used as a fixed position for placing the user's palm.

[0015] Optionally, in the smart door lock, the periscope optical module includes a near-infrared light source, a reflector, an imaging lens group, and an image sensor; The near-infrared light source is used to emit infrared rays to the user's palm when the user's palm is detected to be placed in the area of ​​the glass panel; The reflector is used to concentrate and guide the infrared light reflected from the palm to the imaging lens group; The imaging lens group is used to optimize the infrared light signal transmitted by the reflector to obtain an optimized infrared light signal, and to focus the optimized infrared light signal onto the image sensor; The image sensor is used to convert the optimized infrared light signal into a digital image signal and send the digital image signal to the control processing unit.

[0016] Optionally, the smart door lock further includes a drive circuit, which includes a motor drive module and a lock cylinder drive mechanism. The control processing unit includes a microprocessor, a memory, and a recognition algorithm module; The microprocessor is used to convert the digital image signal into a palmar vein pattern image; The memory is used to pre-store the palm vein feature values ​​of selected users; The recognition algorithm module is used to extract palm vein feature values ​​from the palm vein dark pattern image and verify whether the palm vein feature values ​​exist in the memory; The microprocessor is also configured to send a successful verification result to the drive circuit if the palm vein feature value exists in the memory; The driven circuit is used to control the motor drive module and the lock cylinder drive mechanism to perform the unlocking operation based on the successful verification result.

[0017] In this invention, the periscope palm vein recognition method is applied to a smart lock. The smart lock includes a lock shell with a glass panel, a periscope optical module comprising a near-infrared light source, a reflector, an imaging lens group, and an image sensor, and a control processing unit. The periscope palm vein recognition method includes: when a user's palm is detected to be placed in the area of ​​the glass panel, emitting infrared light to the user's palm through the near-infrared light source; concentrating the infrared light reflected from the palm through the reflector and guiding it to the imaging lens group; optimizing the infrared light signal transmitted by the reflector through the imaging lens group to obtain an optimized infrared light signal, and focusing the optimized infrared light signal onto the image sensor; converting the optimized infrared light signal into a digital image signal through the image sensor, and sending the digital image signal to the control processing unit; converting the digital image signal into a palm vein dark pattern image through the control processing unit, extracting palm vein feature values ​​from the palm vein dark pattern image, verifying whether the palm vein feature values ​​exist in the memory, and if they exist, controlling the smart lock to unlock based on the successful verification result. This invention achieves high-quality palm vein imaging at ultra-close distances through a periscope optical structure design. Users do not need to deliberately adjust their hand position and distance; they can simply hold the door handle naturally to complete identity recognition. It is easy to operate and has a high recognition success rate. Attached Figure Description

[0018] Figure 1 This is a structural diagram of a preferred embodiment of the smart door lock of the present invention; Figure 2 This is a flowchart of a preferred embodiment of the periscope palm vein recognition method of the present invention; Figure 3 This is a flowchart illustrating the process of using a smart door lock to complete the recognition process in a preferred embodiment of the periscope palm vein recognition method of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0020] The existing palm vein recognition technology has the following main technical problems when applied to smart door lock products: (1) The recognition distance is difficult to accurately determine: Traditional palm vein recognition devices require users to place their palms within a specific distance range. However, in door lock usage scenarios, it is difficult to accurately determine the optimal recognition distance when users are holding items or when people of different heights use the device, resulting in a high recognition failure rate.

[0021] (2) Inability to recognize at close range: When the user's palm is too close to the recognition device (less than 10 cm), the traditional optical system cannot form a clear image, which is a technical problem in the industry. In door lock applications, when the user naturally holds the door handle, the distance between the palm and the door lock panel is often too close, exceeding the recognition range of traditional devices.

[0022] (3) Poor user experience: Existing devices require users to consciously adjust their hand position and distance, which is cumbersome and does not conform to ergonomic principles. In access control scenarios, users expect to complete identity recognition quickly and naturally, rather than needing to learn specific usage postures.

[0023] (4) Low recognition success rate: Due to distance and angle limitations, the recognition success rate of traditional palm vein recognition devices is often less than 90% in actual use, especially when the distance is inappropriate, the recognition failure rate increases significantly.

[0024] To overcome the aforementioned shortcomings of the prior art, the present invention provides a smart door lock, such as... Figure 1 As shown, the smart door lock includes: a door lock housing, a periscope optical module, a control processing unit, and a drive circuit.

[0025] The door lock housing is designed with standard door lock dimensions and has a glass panel. The area of ​​the glass panel is used as a fixed position for placing the user's palm, thereby achieving precise positioning and solving the problem that the user does not know where the best position for placing their palm is.

[0026] The periscope optical module adopts a periscope optical path design, which is an imaging system design that uses optical prisms or mirrors to fold the light path from the conventional vertical direction to the horizontal direction. Its core lies in changing the physical direction of the light path, which can achieve long focal length within a limited thickness and improve zoom image quality.

[0027] The periscope optical module in this invention utilizes a reflector (typically placed at a 45° angle) to deflect the originally linear infrared light path (from the light source → palm → lens group → image sensor CMOS) into a non-linear path. This allows the light path, which previously required a relatively long linear space, to be compressed into a compact three-dimensional space. Thus, by altering the direction of the infrared light path through the reflector, clear imaging of close-range objects is achieved without sacrificing image quality. Therefore, what previously required a distance of 10cm from the door lock device to achieve a clear image now only requires 2-3cm, solving the problem of the door lock not recognizing a hand touching it at close range.

[0028] The periscope optical module includes a near-infrared light source, a reflector, an imaging lens group, and an image sensor.

[0029] The near-infrared light source employs a near-infrared LED array with a wavelength of 700-1100nm, uniformly distributed around the glass panel. This provides illumination for palm vein imaging and, when the user's palm is detected placed on the glass panel, emits infrared light onto the user's palm. The 700-1100nm near-infrared light has moderate penetrability, easily passing through the epidermis and dermis of the palm, avoiding interference from fingerprints and textures on the skin surface, and accurately reaching the internal vein area. Hemoglobin in the veins has a strong absorption capacity for this wavelength of infrared light, absorbing a large amount of light; while surrounding muscles, fat, and other tissues have weak absorption capacity, reflecting most of the light, creating a contrast of "weak light in the vein area and strong light in the background area." This contrasting light signal is the basis for subsequent focusing by the imaging lens group and CMOS conversion by the image sensor. Without the "irradiation-absorption-reflection" process of infrared light, it is impossible to generate a light signal that reflects the vein distribution, let alone generate a dark vein image.

[0030] The reflectors are used to concentrate and guide the infrared light reflected from the palm to the imaging lens group. Each reflector is a high-reflectivity plane mirror or a slightly curved mirror, and precise angle design enables optical path folding and imaging distance adjustment. The purpose of the reflector group is to optimize infrared light path transmission, placing the near-infrared emitter, the palm acquisition area, and the image sensor in the optimal optical path. Concentrating the infrared light reflected from the palm and guiding it to the imaging lens group enhances signal strength and increases the contrast between the background and the dark vein patterns. This ensures that the infrared light accurately targets and effectively captures the palm while reducing interference, resulting in clearer vessel outlines in the dark vein image, thus achieving clear palm vein images at close range.

[0031] The imaging lens group is used to optimize the infrared light signal transmitted by the reflector to obtain an optimized infrared light signal, and to focus the optimized infrared light signal onto the image sensor; such as Figure 1 As shown, the imaging lens group is a lens assembly composed of multiple lenses. This imaging lens group, acting as an "optical preprocessing" step, primarily optimizes the light signal. It precisely focuses the diffused infrared light reflected from the palm onto the image sensor CMOS, enhancing signal strength and preventing image blurring. The combination of multiple lenses counteracts optical distortion, ensuring that the shape and proportion of the vascular patterns match the actual vein distribution, thus avoiding feature distortion. It filters out unwanted stray light, enhancing image detail and allowing even small vein branches to be clearly presented, providing sufficient information for feature extraction. Finally, it ensures that the light clearly reveals the differences in brightness between the blood vessels and the background.

[0032] The image sensor converts the optimized infrared light signal into a digital image signal and sends the digital image signal to the control processing unit. The surface of the image sensor is covered with a photodiode array. When infrared reflected light from the imaging lens group illuminates the image sensor, the photodiodes utilize the photoelectric effect to convert the difference in light signals between the palm vein region (weak reflected light) and the background tissue (strong reflected light) into corresponding weak current signals. Simultaneously, the transistor integrated into the image sensor directly amplifies the current signal at the detection point, and then, through an on-chip analog-to-digital converter, converts the amplified analog electrical signal into a digital image signal, providing basic data for subsequent image processing. For the image sensor, on the one hand, by optimizing pixel arrangement and fill rate, it can clearly capture the details of small vein branches, ensuring that the contours and direction of the vascular patterns are highly consistent with the actual vein distribution, avoiding feature distortion and providing clear material for subsequent vein feature extraction; on the other hand, its frame rate can flexibly adapt to the needs of palm vein recognition, typically achieving a fast acquisition standard, avoiding image blurring caused by slight hand movements, and improving recognition convenience.

[0033] The control processing unit is mainly used for image processing, feature extraction, and identity verification. The control processing unit includes a microprocessor, a memory, and a recognition algorithm module. The microprocessor converts the digital image signal into a clear palm vein image. The memory pre-stores the palm vein feature values ​​(i.e., unique features) of selected users. The recognition algorithm module extracts the palm vein feature values ​​from the palm vein image and verifies whether the palm vein feature values ​​exist in the memory. The microprocessor also sends a successful verification result to the driving circuit if the palm vein feature values ​​exist in the memory.

[0034] The drive circuit includes a motor drive module and a lock cylinder drive mechanism; the drive circuit is used to control the motor drive module and the lock cylinder drive mechanism to perform an unlocking operation based on the successful verification result.

[0035] Figure 1 In the diagram, 1 represents the user's palm, 2 represents the near-infrared light source, 3 represents the reflector, 4 represents the imaging lens group, 5 represents the image sensor, 6 represents the glass panel, and 7 represents the front panel of the lock.

[0036] Furthermore, based on the aforementioned smart door lock, this invention also provides a periscope palm vein recognition method, such as... Figure 2 and Figure 3 As shown, the periscope palm vein recognition method includes the following steps: Step S10: When the user's palm is detected to be placed in the area of ​​the glass panel, infrared rays are emitted to the user's palm through the near-infrared light source.

[0037] Specifically, a near-infrared LED array with a wavelength of 700-1100nm is used, and the near-infrared LED array is evenly distributed around the glass panel; when the near-infrared LED array detects that the user's palm is placed in the area of ​​the glass panel, infrared rays are emitted through the near-infrared LED array to the vein area inside the user's palm.

[0038] Step S20: The infrared rays reflected by the palm are concentrated and guided to the imaging lens group through the reflector.

[0039] Specifically, a plane mirror or a slightly curved mirror with high reflectivity is used as the reflector and placed at a preset angle (e.g., 45°). When the infrared light reflected by the palm is transmitted to the reflector, the reflector optimizes the infrared light path transmission and concentrates the infrared light to the imaging lens group.

[0040] Step S30: Optimize the infrared light signal transmitted by the reflector through the imaging lens group to obtain an optimized infrared light signal, and focus the optimized infrared light signal onto the image sensor.

[0041] Specifically, multiple lenses are assembled into an imaging lens group, which optimizes the infrared light signal transmitted by the reflector, cancels optical distortion, controls the shape and proportion of the vascular dark lines to be consistent with the actual vein distribution, filters out invalid stray light, and obtains an optimized infrared light signal; the imaging lens group focuses the obtained optimized infrared light signal onto the image sensor.

[0042] Step S40: The optimized infrared light signal is converted into a digital image signal by the image sensor, and the digital image signal is sent to the control processing unit.

[0043] Specifically, the surface of the image sensor is covered with a photodiode array. When infrared reflected light from the imaging lens group shines on the image sensor, the photodiode array uses the photoelectric effect to convert the difference in light signals between the palm vein area and the background tissue into corresponding weak current signals. The transistor integrated into the image sensor directly amplifies the current signal at the detection point, and then the amplified analog electrical signal is converted into a digital image signal by an on-chip analog-to-digital converter.

[0044] Step S50: The control processing unit converts the digital image signal into a palm vein dark pattern image, extracts palm vein feature values ​​from the palm vein dark pattern image, verifies whether the palm vein feature values ​​exist in the memory, and if they exist, controls the smart door lock to unlock based on the successful verification result.

[0045] Specifically, the microprocessor of the control processing unit converts the digital image signal into a palm vein dark pattern image; the memory of the control processing unit pre-stores the palm vein feature values ​​of the selected user; the recognition algorithm module of the control processing unit extracts the palm vein feature values ​​from the palm vein dark pattern image and verifies whether the palm vein feature values ​​exist in the memory; if the palm vein feature values ​​exist in the memory, the microprocessor sends the verification success result to the drive circuit of the smart door lock; the drive circuit controls the motor drive module and the lock cylinder drive mechanism to perform the unlocking operation according to the verification success result.

[0046] The technical effects that this invention can bring are as follows: (1) Solved the problem of close-range recognition: Through the periscope optical structure design, high-quality palm vein imaging at ultra-close distance was successfully realized, breaking through the technical bottleneck of traditional equipment being unable to recognize at close distance, and the recognition success rate was increased to over 99%.

[0047] (2) Improved user experience: Users do not need to deliberately adjust the position and distance of their hands. They can complete the identity recognition by simply holding the door handle naturally, realizing the convenient operation of "opening with one grip" and greatly improving the user experience.

[0048] (3) Improved recognition accuracy and speed: Optimized optical design and image processing algorithm shorten the recognition time to less than 1 second and the recognition accuracy reaches more than 99.5%, which is significantly better than traditional palm vein recognition devices.

[0049] (4) Miniaturized integration: Through the optical path folding design, the imaging system that originally required a long optical path is integrated into the limited space of a standard door lock, realizing the perfect integration of palm vein recognition function and door lock product.

[0050] (5) Reduced system cost: No additional distance sensors and position guidance devices are required, which simplifies the system structure, reduces manufacturing costs, and facilitates large-scale application.

[0051] (6) Enhanced security and reliability: Palm vein recognition technology itself has high security. Combined with the close-range recognition advantage of this invention, it effectively prevents long-range forgery attacks, while the stability and reliability of the system are significantly improved.

[0052] In summary, this invention provides a periscope palm vein recognition method and a smart lock. The periscope palm vein recognition method is applied to a smart lock, which includes a lock shell with a glass panel, a periscope optical module comprising a near-infrared light source, a reflector, an imaging lens group, and an image sensor, and a control processing unit. The periscope palm vein recognition method includes: when a user's palm is detected to be placed in the area of ​​the glass panel, emitting infrared light to the user's palm through the near-infrared light source; concentrating the infrared light reflected from the palm through the reflector and guiding it to the imaging lens group; optimizing the infrared light signal transmitted by the reflector through the imaging lens group to obtain an optimized infrared light signal, and focusing the optimized infrared light signal onto the image sensor; converting the optimized infrared light signal into a digital image signal through the image sensor, and sending the digital image signal to the control processing unit; converting the digital image signal into a palm vein dark pattern image through the control processing unit, extracting palm vein feature values ​​from the palm vein dark pattern image, verifying whether the palm vein feature values ​​exist in the memory, and if they exist, controlling the smart lock to unlock based on the successful verification result. This invention achieves high-quality palm vein imaging at ultra-close distances through a periscope optical structure design. Users do not need to deliberately adjust their hand position and distance; they can simply hold the door handle naturally to complete identity recognition. It is easy to operate and has a high recognition success rate.

[0053] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or smart lock 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 smart lock. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or smart lock that includes that element.

[0054] Of course, those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware (such as a processor, controller, etc.). The program can be stored in a computer-readable storage medium, and when executed, it can include the processes described in the above method embodiments. The computer-readable storage medium can be a memory, magnetic disk, optical disk, etc.

[0055] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A periscope-style palm vein recognition method, characterized in that, The periscope palm vein recognition method is applied to a smart door lock, which includes a door lock shell with a glass panel, a periscope optical module including a near-infrared light source, a reflector, an imaging lens group and an image sensor, and a control processing unit. The periscope-style palm vein identification method includes: When the user's palm is detected to be placed in the area of ​​the glass panel, infrared rays are emitted to the user's palm through the near-infrared light source; The infrared light reflected from the palm is concentrated and guided to the imaging lens group by the reflector. An optimized infrared light signal is obtained by optimizing the infrared light signal transmitted by the reflector through the imaging lens group, and the optimized infrared light signal is focused onto the image sensor; The optimized infrared light signal is converted into a digital image signal by the image sensor, and the digital image signal is sent to the control processing unit. The control processing unit converts the digital image signal into a palm vein dark pattern image, extracts palm vein feature values ​​from the palm vein dark pattern image, verifies whether the palm vein feature values ​​exist in the memory, and if they exist, controls the smart door lock to unlock based on the successful verification result.

2. The periscope-type palm vein recognition method according to claim 1, characterized in that, When the user's palm is detected to be placed on the area of ​​the glass panel, infrared rays are emitted to the user's palm via the near-infrared light source, specifically including: A near-infrared LED array with a wavelength of 700-1100nm is used, and the near-infrared LED array is evenly distributed around the glass panel; When the near-infrared LED array detects that the user's palm is placed in the area of ​​the glass panel, it emits infrared rays to the vein area inside the user's palm.

3. The periscope-type palm vein recognition method according to claim 1, characterized in that, The process of concentrating and guiding the infrared rays reflected from the palm through the reflector to the imaging lens group specifically includes: High-reflectivity plane mirrors or slightly curved mirrors are used as reflectors and placed at a preset angle; When infrared light reflected from the palm is transmitted to the reflector, the reflector optimizes the infrared light path transmission and concentrates the infrared light to the imaging lens group.

4. The periscope palm vein recognition method according to claim 1, characterized in that, The process of optimizing the infrared light signal transmitted by the reflector through the imaging lens group to obtain an optimized infrared light signal, and focusing the optimized infrared light signal onto the image sensor, specifically includes: Multiple lenses are combined to form an imaging lens group, which optimizes the infrared light signal transmitted by the reflector, cancels optical distortion, controls the shape and proportion of the dark vein pattern to be consistent with the actual vein distribution, filters out invalid stray light, and obtains an optimized infrared light signal. The imaging lens group focuses the obtained optimized infrared light signal onto the image sensor.

5. The periscope-type palm vein recognition method according to claim 1, characterized in that, The step of converting the optimized infrared light signal into a digital image signal using the image sensor and sending the digital image signal to the control processing unit specifically includes: The image sensor surface is covered with a photodiode array. When infrared reflected light from the imaging lens group shines on the image sensor, the photodiode array uses the photoelectric effect to convert the difference in light signals between the palm vein area and the background tissue into corresponding weak current signals. The transistor integrated in the image sensor directly amplifies the current signal at the detection point, and then the amplified analog electrical signal is converted into a digital image signal by an on-chip analog-to-digital converter.

6. The periscope-type palm vein recognition method according to claim 1, characterized in that, The process involves converting the digital image signal into a palm vein dark pattern image via the control processing unit, extracting palm vein feature values ​​from the palm vein dark pattern image, verifying whether the palm vein feature values ​​exist in the memory, and if they exist, controlling the smart door lock to unlock based on the successful verification result. Specifically, this includes: The microprocessor of the control processing unit converts the digital image signal into a palm vein dark pattern image; The palm vein feature values ​​of the selected user are pre-stored in the memory of the control processing unit; The recognition algorithm module of the control processing unit extracts palm vein feature values ​​from the palm vein dark pattern image and verifies whether the palm vein feature values ​​exist in the memory. If the palm vein feature value exists in the memory, the microprocessor sends the successful verification result to the drive circuit of the smart door lock; The driven circuit controls the motor drive module and the lock cylinder drive mechanism to perform the unlocking operation based on the successful verification result.

7. A smart door lock, characterized in that, The smart door lock includes: a door lock housing, a periscope optical module, and a control processing unit; the smart door lock is used to implement the periscope palm vein recognition method according to any one of claims 1-6.

8. The smart door lock according to claim 7, characterized in that, The door lock housing is provided with a glass panel, and the area of ​​the glass panel is used as a fixed position for the user's palm.

9. The smart door lock according to claim 8, characterized in that, The periscope optical module includes a near-infrared light source, a reflector, an imaging lens group, and an image sensor; The near-infrared light source is used to emit infrared rays to the user's palm when the user's palm is detected to be placed in the area of ​​the glass panel; The reflector is used to concentrate and guide the infrared light reflected from the palm to the imaging lens group; The imaging lens group is used to optimize the infrared light signal transmitted by the reflector to obtain an optimized infrared light signal, and to focus the optimized infrared light signal onto the image sensor; The image sensor is used to convert the optimized infrared light signal into a digital image signal and send the digital image signal to the control processing unit.

10. The smart door lock according to claim 9, characterized in that, The smart door lock also includes a drive circuit, which includes a motor drive module and a lock cylinder drive mechanism; The control processing unit includes a microprocessor, a memory, and a recognition algorithm module; The microprocessor is used to convert the digital image signal into a palmar vein pattern image; The memory is used to pre-store the palm vein feature values ​​of selected users; The recognition algorithm module is used to extract palm vein feature values ​​from the palm vein dark pattern image and verify whether the palm vein feature values ​​exist in the memory; The microprocessor is also configured to send a successful verification result to the drive circuit if the palm vein feature value exists in the memory; The driven circuit is used to control the motor drive module and the lock cylinder drive mechanism to perform the unlocking operation based on the successful verification result.

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