An OCT-based animal ophthalmic examination device and an automatic alignment method thereof

Abstract

The application discloses an animal ophthalmic examination device based on OCT and an automatic alignment method thereof. The device comprises: an electrically adjustable platform for carrying an animal and adjusting the body position of the animal; an OCT system for acquiring an eye tomographic image of the animal; a focusing system for realizing adaptive focusing between an OCT system scanning beam and an animal eyeball; a half-transmission half-reflection mirror; an automatic recognition system for acquiring an eye image of the animal and recognizing an eyeball position and an optical axis direction; an OCT device electrically adjustable platform for carrying the OCT system and adjusting the spatial position of an OCT probe; a data processing system for processing image data and controlling an alignment process; and a control system in electrical signal connection with the data processing system, the OCT device electrically adjustable platform, the focusing system, the automatic recognition system, the OCT system and the electrically adjustable platform, and capable of automatically controlling the movement and focusing of each system according to the feedback of the data processing system. The application has high automation degree, strong compatibility, and improves the scanning precision and consistency of the device.

Description

Technical Field

[0001] This invention belongs to the field of ophthalmic optical coherence tomography (OCT) imaging technology, specifically relating to an OCT-based animal ophthalmic examination device and its automatic alignment method. Background Technology

[0002] Optical coherence tomography (OCT) technology, with its advantages of being non-invasive, high-resolution, and providing real-time tomographic imaging, has become a core tool for basic ophthalmic research and clinical diagnosis. In research on ophthalmic diseases (such as glaucoma, retinal degeneration, diabetic retinopathy, and corneal diseases), laboratory animals are indispensable research vehicles. By performing in vivo OCT scans on anesthetized laboratory animals, key morphological data such as the thickness of each retinal layer, the morphology of the optic nerve fiber layer, macular structure, and anterior chamber angle parameters can be accurately obtained, providing important quantitative evidence for exploring disease pathogenesis, screening candidate drugs, and verifying efficacy.

[0003] In existing technologies, alignment methods for post-anesthesia animal ophthalmic OCT imaging primarily rely on manual and semi-automatic alignment. In manual alignment mode, operators must manually adjust the X / Y / Z axis displacement of the stage and the pitch and deflection angles of the OCT probe using an auxiliary eyepiece or by visual observation to align the scanning beam with the center of the pupil and the visual axis of the animal's eyeball. This method is highly dependent on the operator's experience and skill; the alignment process is cumbersome and time-consuming, typically requiring 3-10 minutes per alignment. It is not only inefficient but also prone to human error, causing the scanning beam to deviate from the visual axis, resulting in blurred images, tomographic misalignment, and other problems that affect the accuracy of subsequent parameter measurements.

[0004] While semi-automatic alignment optimizes the operation process to some extent, and some devices integrate infrared pupil recognition modules and two-dimensional motorized stages to achieve coarse pupil localization, significant drawbacks remain: First, it lacks the ability to accurately identify the angle of the eye's optical axis (visual axis), only achieving two-dimensional localization of the pupil center. It cannot guarantee that the scanning beam is coaxial with the eye's optical axis, easily leading to off-center scanning and resulting in inaccurate imaging of critical areas such as the macula and optic disc. Second, it lacks a dynamic motion compensation mechanism designed for the physiological characteristics of anesthetized animals. Anesthetized experimental animals (especially small animals such as mice and rats) may exhibit spontaneous nystagmus, respiratory fluctuations, and heartbeat disturbances. The micro-displacement of the eyeball (the amplitude is usually 5-50μm, the frequency is 0.5-5Hz) cannot be compensated for in real time by manual or simple semi-automatic systems. This will lead to scanning tomographic misalignment and image artifacts, and the measurement error of key parameters such as retinal thickness will exceed 15%, which cannot meet the needs of longitudinal comparative studies. Third, it lacks depth adaptive focusing ability. After anesthesia, the anterior chamber depth of the animal's eyeball will fluctuate by ±200μm. Moreover, there are significant differences in the refractive state and axial length of the eyeball between different species and individuals. Manual focusing is inefficient and it is difficult to adapt to the curvature changes caused by corneal dehydration during long-term scanning, which can easily lead to the focus deviating from the retina.

[0005] Furthermore, while some existing OCT automatic alignment technologies for humans possess functions such as fixation tracking and eye movement compensation, they cannot be directly transferred to imaging scenarios in anesthetized animals. Automatic alignment in human OCT relies on the subject's active fixation, but anesthetized experimental animals lose their autonomous control and cannot perform active fixation, rendering the tracking function of such technologies completely ineffective. Simultaneously, existing patents related to animal ophthalmic OCT primarily focus on optical path structure design, scanning mode optimization, or image processing algorithms, failing to systematically address the core technical challenges of automatic alignment at the optical axis level, real-time micro-motion compensation, and adaptive focusing in anesthetized animals. This results in low alignment success rates (typically below 60% in small animal models), low experimental throughput, and imaging times of 15-30 minutes per animal, making it difficult to support large-sample, long-term animal experimental research.

[0006] Furthermore, existing technologies suffer from poor consistency in repeated scans, with intraclass correlation coefficients (ICC) below 0.7, making it impossible to guarantee the comparability of data from multiple longitudinal follow-ups (such as baseline, post-drug administration, and experimental endpoints). Additionally, the devices have poor compatibility, making them difficult to adapt to different species and sizes of experimental animals, resulting in insufficient versatility. These issues limit the effectiveness of OCT technology in ophthalmic research on anesthetized animals, necessitating a targeted solution to these pain points with a post-anesthetized animal ophthalmic OCT device and an automated alignment method.

[0007] Therefore, how to provide an OCT-based animal ophthalmological examination device and its automatic alignment method is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] In view of this, the present invention provides an OCT-based animal ophthalmological examination device and its automatic alignment method, which has a high degree of automation, strong compatibility, and improves the scanning accuracy and consistency of the device.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: an OCT-based animal ophthalmological examination device, comprising:

[0010] An electrically adjustable platform for supporting animals and adjusting their position; OCT system, used to acquire tomographic images of the eyes of animals; A focusing system, located between the electrically adjustable stage and the OCT system, is used to achieve adaptive focusing between the scanning beam of the OCT system and the animal's eyeball; A semi-transparent mirror, wherein the semi-transparent mirror is located in the optical path between the OCT system and the focusing system; An automatic identification system, located on the reflected light path of the semi-transparent mirror, is used to acquire images of the animal's eyes and identify the position of the eyeballs and the direction of the optical axis. An electric adjustment platform for OCT equipment is used to support the OCT system and adjust the spatial position of the OCT probe. The data processing system is used to process image data and control the alignment process; The control system is connected to the data processing system, the electric adjustment platform of the OCT equipment, the focusing system, the automatic identification system, the OCT system, and the electric adjustment platform via electrical signals. It can automatically control the movement and focusing of each system based on feedback from the data processing system.

[0011] The technical advantages of this invention are as follows: An automatic recognition system acquires real-time images of the animal's eyes, automatically identifying the eye's position and optical axis direction. After data processing, the control system drives the electrically adjustable stage (adjusting the animal's position) and the electrically adjustable stage of the OCT device (adjusting the spatial position of the OCT probe), forming a closed-loop control of "recognition → calculation → drive → verification." This eliminates the need for manual focusing or alignment, making it particularly suitable for animals that cannot fixate or whose eyes move frequently, significantly improving examination efficiency and repeatability. A semi-transparent, semi-reflective mirror is located between the OCT system and the focusing system; its transmitted light path allows the OCT scanning beam to pass through, while its reflected light path provides illumination / imaging light for the automatic recognition system. Both optical systems share the focusing system and subsequent optical path, ultimately converging on the animal's eye. The "eye position / optical axis" seen by the recognition system is strictly coaxial with the actual optical path of the OCT scan, eliminating the systematic errors of traditional paraxial alignment. No separate focusing mechanism is needed for the recognition system, resulting in a compact structure and controllable cost. The electrically adjustable stage is responsible for the overall animal position, such as tilting, while the electrically adjustable stage of the OCT equipment is responsible for the fine spatial positioning of the OCT probe (including the scanning galvanometer and focusing lens group). Together, they can cover the spatial positioning needs of eyeballs in animals of different sizes, from mice and rats to rabbits and dogs. The coarse adjustment (stage) and fine adjustment (probe stage) have clearly defined roles, resulting in a large dynamic range and high positioning accuracy. This invention, through "coaxial common optical path automatic recognition + dual electrically adjustable stage hierarchical alignment + adaptive focusing + closed-loop real-time tracking," achieves fully automatic, high-precision, and manual-intervention-free ophthalmic OCT examination of moving animals, significantly improving efficiency, image quality, and animal compatibility.

[0012] Preferably, the electrically adjustable platform is a servo motor-controlled rotary table, and the surface of the rotary table is used to support the animal to be tested.

[0013] The resulting technical effect is that by using a servo motor-controlled rotary table as an electric adjustment platform, high-precision, programmable, closed-loop automatic rotation adjustment of the animal's overall position is achieved, ensuring that the optical axis of the eyeball is quickly and accurately coaxial with the OCT scanning beam, thereby improving the degree of alignment automation, repeatability accuracy, and examination efficiency.

[0014] Preferably, the OCT system includes: a light source, a fiber optic coupler, a reference arm, a sample arm, and a spectrometer; The reference arm includes a second collimating lens, a second lens, and a reflecting mirror; The sample arm includes a third collimating lens, a corner bevel prism, a first scanning mirror, and a second scanning mirror; The spectrometer includes a first collimating lens, a grating, a first lens, and a linear camera; The sample light detected by the sample arm and the reference light detected by the reference arm interfere in the fiber optic coupler. The interference light is received by the spectrometer and transmitted to the data processing system to generate a tomographic image of the animal's eye.

[0015] The resulting technical effect is that the OCT system adopts a spectral domain architecture + corner prism optical path adjustment + dual galvanometer scanning + fiber coupling, realizing high-speed, high-sensitivity, three-dimensional, adaptive optical path tomographic imaging of animal eyes, and has the advantages of flexibility, stability and modularity.

[0016] Preferably, the cornerstone prism serves as an optical extension line, and its position is controlled by the control system to move via a linear motor, thereby adjusting the optical path of the sample light to be consistent with that of the reference light.

[0017] The resulting technical effect is that by using a linear motor to drive a corner bevel prism as an optical extension line, fully automatic, high-precision, and wide-range adjustment of the optical path of the sample arm is achieved. This allows for rapid matching of the differences in axial length of different animals (and individuals), ensuring that OCT is always in the best interference state while maintaining beam quality and system stability.

[0018] Preferably, the automatic identification system includes: an illumination source, a cylindrical mirror, a line-scanning galvanometer, an intensity beam splitter, and an area array camera; the light emitted by the illumination source is focused by the cylindrical mirror, then becomes two-dimensional scanning light by the line-scanning galvanometer, and finally reaches the animal's eye after passing through the intensity beam splitter, a semi-transparent mirror, and the focusing system; the reflected light passes through the focusing system, the semi-transparent mirror, the intensity beam splitter, and the focusing lens to reach the area array camera for imaging.

[0019] The resulting technical effect is that the automatic identification system adopts the design of "line scanning illumination + area array imaging + coaxial common optical path", which realizes fast, large field of view, high contrast real-time imaging of animal eyes. It is strictly coaxial with the OCT main optical path, thus providing a reliable guarantee for zero-error automatic alignment, dynamic eye tracking and fully automated inspection process. At the same time, it has a compact structure and controllable cost.

[0020] Preferably, the focusing system is a combination of a 4F focusing system and a zoom electronically tuned lens.

[0021] The resulting technical effect is that the combination of the 4F system and the zoom electronically tuned lens achieves millisecond-level response and wide-range continuous adaptive focusing, while maintaining the conjugate relationship of the scanning optical system and image plane stability, providing a high-performance, compact, and low-power solution for autofocus under multi-species, multi-site, and dynamic eye-tracking conditions.

[0022] Preferably, the electric adjustment platform of the OCT device is a six-axis displacement adjustment platform, and the OCT probe of the OCT system is mounted on the platform of the electric adjustment platform of the OCT device.

[0023] The resulting technical effects are: using a six-axis displacement adjustment stage to support the OCT probe, achieving full-degree-of-freedom, high-precision, dynamic closed-loop adjustment of the probe's spatial position and orientation, supporting real-time compensation in eye tracking, and working in conjunction with the electric adjustment stage to complete a coarse-to-fine alignment strategy. At the same time, it simplifies the assembly and calibration process, significantly improving the system's positioning accuracy, imaging flexibility, and long-term reliability.

[0024] Preferably, it also includes a fluorescence detection system, which is implemented by the control system switching the dichroic mirror and filter wheel in the automatic recognition system to generate angiographic images of the animal fundus.

[0025] The resulting technical effect is that by integrating a controllable dichroic mirror and filter wheel into the automatic recognition system, this solution achieves seamless integration of OCT structural imaging and fundus fluorescence angiography functional imaging with minimal hardware increment. It supports multi-channel, multi-dye, and fully automated multimodal detection, greatly expanding the application value of the device in basic ophthalmic research and drug evaluation.

[0026] Preferably, the fluorescence detection system is divided into a white light combined with a filter system and a single-wavelength light excitation system based on the difference in light source; the light source of the white light combined with a filter system is a white LED or a xenon lamp, and the light source of the single-wavelength light excitation system is a laser or a single-wavelength LED.

[0027] The resulting technical effect is that the fluorescence detection system is divided into two modes: "white light + filter" and "single-wavelength light excitation". The latter utilizes the flexibility and multi-color advantages of broadband light sources and the high purity and high signal-to-noise ratio advantages of narrowband light sources, respectively. This allows users to flexibly select or combine modes according to dye characteristics, fluorescence intensity, cost budget, and safety requirements, achieving a wide range of coverage from conventional angiography to high-sensitivity multicolor fluorescence imaging, and improving the system's versatility, performance adjustability, and market adaptability.

[0028] Preferably, the control system includes a host computer and a microcontroller. The host computer sends position information, angle information, and compensation amount to the microcontroller via USB serial communication, and the microcontroller controls the electric adjustment platform and the electric adjustment platform of the OCT equipment to perform corresponding movements.

[0029] The resulting technical effect is that by adopting a hierarchical control architecture of "host computer (computation) + microcontroller (execution)", and transmitting position, angle and dynamic compensation through USB serial communication, complex image processing and real-time motor control are decoupled. This takes into account the system's high computing power requirements, real-time response, cost control, ease of development and maintenance flexibility, and is a reliable foundation for fully automatic eye tracking and precise alignment processes.

[0030] Preferably, it also includes a display system, which is electrically connected to the data processing system for focusing and displaying scanned images.

[0031] The resulting technical effects are as follows: the display system, as the core interface for human-computer interaction, realizes real-time visualization of the alignment and focusing process, multimodal image fusion analysis on the same screen, intuitive annotation and measurement functions, and status feedback and safety monitoring of the fully automatic process. This greatly improves the intuitiveness of operation, the convenience of diagnosis, the traceability of data, and the overall usability of the system, making complex multi-degree-of-freedom animal ophthalmic OCT examinations more flexible and convenient.

[0032] The present invention also discloses an automatic alignment method for animal ophthalmic OCT based on the above-mentioned examination device, which includes the following steps: S1: The automatic recognition system acquires a three-dimensional image of the animal, identifies the position of the animal's head, and controls the electric adjustment platform of the OCT device to move the animal's head to the center of the field of view. S2: The data processing system further identifies the pupil position of the animal's eye, and controls the movement of the electric adjustment stage of the OCT device and the tilting of the electric adjustment platform through the control system, so that the pupil of the detected eye moves to the center of the field of view. S3: Identify the direction of the optical axis of the eyeball and control the deflection angle of the electric adjustment stage to make the OCT scanning beam coaxial with the optical axis of the eyeball; S4: Perform OCT optical path calibration by moving the corner bevel prism to make the optical path of the sample arm and the reference arm consistent. S5: The focusing system automatically adjusts the focal length according to the clarity of the fundus image, and further refines the focus according to the clarity of the OCT tomographic image; S6: Real-time eye movement tracking; the control system controls the electric adjustment platform of the OCT device to dynamically compensate for micro-displacements caused by nystagmus, breathing or heartbeat, so as to achieve eye tracking and alignment maintenance. S7: Start the OCT system to scan and generate a tomographic image of the animal's eye.

[0033] The resulting technical effect is: Attached Figure Description Figure 1 This is a schematic diagram of an animal ophthalmological examination device based on OCT according to the present invention; Figure 2 This is an application diagram of an automatic identification system for an animal ophthalmology examination device based on OCT, according to the present invention; Figure 3 This is an application diagram of the white light combined with filter system of an OCT-based animal ophthalmic examination device according to the present invention; Figure 4This is an application diagram of the single-wavelength light excitation system of an OCT-based animal ophthalmic examination device according to the present invention; Figure 5 This is a schematic diagram illustrating the application of an OCT-based animal ophthalmological examination device according to the present invention.

[0034] 1-Electric adjustment stage, 2-OCT system, 21-Light source, 22-Fiber optic coupler, 23-Reference arm, 231-Second collimating lens, 232-Second lens, 233-Reflector, 24-Sample arm, 241-Third collimating lens, 242-Corner prism, 243-First scanning galvanometer, 244-Second scanning galvanometer, 25-Spectrometer, 251-First collimating lens, 252-Grating, 253-First lens, 254-Linear camera, 3-Focusing system, 31-Variable zoom electrically tuned lens, 32-4F focusing system, 4-Semi-transparent mirror, 5-Automatic recognition system, 51-Illumination source, 52-Cylindrical mirror, 53-Line scanning galvanometer, 54-Intensity spectrometer, 54-Area array camera, 6-OCT equipment electric adjustment stage, 7-Data processing system, 8-Control system, 9-Display system. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only 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.

[0036] See the appendix of this invention. Figures 1 to 5 According to an embodiment of the present invention, an OCT-based animal ophthalmic examination device includes: The electrically adjustable platform 1 is used to support the animal and adjust its position. OCT system 2 is used to acquire tomographic images of the animal's eye. The focusing system 3 is located between the electric adjustment stage 1 and the OCT system 2, and is used to achieve adaptive focusing between the scanning beam of the OCT system 2 and the animal's eyeball. A semi-transparent mirror 4 is located in the optical path between the OCT system 2 and the focusing system 3. Automatic recognition system 5, located on the reflected light path of semi-transparent mirror 4, is used to acquire images of the animal's eyes and identify the position of the eyeball and the direction of the optical axis. The electric adjustment platform 6 of the OCT equipment is used to support the OCT system 2 and adjust the spatial position of the OCT probe. Data processing system 7 is used to process image data and control the alignment process; The control system 8 is electrically connected to the data processing system 7, the electric adjustment stage 6 of the OCT equipment, the focusing system 3, the automatic identification system 5, the OCT system 2, and the electric adjustment platform 1, and can automatically control the movement and focusing of each system according to the feedback of the data processing system.

[0037] In other embodiments, the electrically adjustable platform 1 is a servo motor-controlled rotary table, and the surface of the rotary table is used to support the animal to be tested.

[0038] In some other specific embodiments, the OCT system 2 includes: a light source 21, an optical fiber coupler 22, a reference arm 23, a sample arm 24, and a spectrometer 25; Reference arm 23 includes a second collimating lens 231, a second lens 232, and a reflecting mirror 233; Sample arm 24 includes a third collimating lens 241, a corner cube prism 242, a first scanning galvanometer 243, and a second scanning galvanometer 244; The spectrometer 25 includes a first collimating lens 251, a grating 252, a first lens 253, and a linear camera 254; The sample light detected by the sample arm and the reference light detected by the reference arm interfere in the fiber optic coupler. The interference light is received by the spectrometer and transmitted to the data processing system to generate a tomographic image of the animal's eye.

[0039] In the OCT system, the light source is split into two beams after passing through the fiber optic coupler 22. One beam is collimated into parallel light by the second collimating lens 231, then focused by the second lens 232, and reflected back by the mirror 233. This part is the reference beam. Another beam of light is collimated into parallel light by the third collimating lens 241, then passes through the optical extension line, the first scanning galvanometer 243, the second scanning galvanometer 244, the semi-transparent mirror 4, and the focusing system 3 before reaching the eye of the animal being tested. The light reflected back is the sample light, and this part is called the sample arm. Then the reference light and the sample light interfere in the fiber optic coupler 22 to form interference light, which is received by the spectrometer 25 to generate a tomographic image of the animal's eye.

[0040] The spectrometer 25 includes a first collimating lens 251, a grating 252, a first lens 253, and a linear camera 254. Interference light from the fiber optic coupler 22 is collimated by the first collimating lens 251, then passes through the grating 252 and the first lens 253 to reach the linear camera 254. The linear camera 254 is connected to the control system 8 and used for imaging. The data processing system 7 performs data processing on the signal light acquired by the linear camera 254, including Fourier transform, phase extraction, and background filtering, to generate a tomographic image of the animal's eye. The control system 8 can control a motor to move the optical extension line so that the sample light and reference light have the same optical path. Simultaneously, it controls a focusing system via a motor to scan the anterior and posterior segments of the animal's eye. Based on the clarity of the tomographic image obtained from the data processing system, the motor-controlled focusing system further refines the focus, thereby automatically generating clear images of different positions of the animal's eye.

[0041] In some other embodiments, the cornerstone prism 242 serves as an optical extension line, and its position is controlled by the control system 8 to move via a linear motor to adjust the optical path of the sample light to be consistent with that of the reference light.

[0042] In some other specific embodiments, the automatic identification system 5 includes: an illumination source 51, a cylindrical mirror 52, a line scanning galvanometer 53, an intensity beam splitter 54 (which is a semi-transparent and semi-reflective mirror), and an area array camera 55; the light emitted by the illumination source 51 is formed into a line-focused light by the cylindrical mirror 52, and then formed into a two-dimensional scanning light by the line scanning galvanometer 53, and reaches the animal's eye after passing through the intensity beam splitter 54, the semi-transparent and semi-reflective mirror 4, and the focusing system 3; the reflected light reaches the area array camera 55 for imaging after passing through the focusing system 3, the semi-transparent and semi-reflective mirror 4, the intensity beam splitter 54, and the focusing lens.

[0043] In other embodiments, the focusing system 3 is a combination of a 4F focusing system 32 and a zoom electronically tuned lens 31, wherein the 4F focusing system is formed by a first lens and a second lens.

[0044] In some other embodiments, the electric adjustment platform 6 of the OCT device is a six-axis displacement adjustment platform, and the OCT probe of the OCT system 2 is located on the platform of the electric adjustment platform 6 of the OCT device. Specifically, the semi-transparent mirror 4, the automatic recognition system 5 and the focusing system 3 are all located on the platform of the electric adjustment platform 6 of the OCT device.

[0045] When in use, it also includes a fluorescence detection system, which is realized by the control system 8 switching the dichroic mirror and filter wheel in the automatic recognition system 5 to generate angiographic images of animal fundus blood vessels.

[0046] In other embodiments, the fluorescence detection system is divided into a white light combined with a filter system and a single-wavelength light excitation system based on the light source. The white light combined with a filter system uses a white LED or xenon lamp as its light source. This white light is collimated into parallel light by a collimating lens. After passing through an excitation filter group, the parallel white light is converted into green light, ultraviolet light, or other excitation light corresponding to animal fundus fluorescein angiography. This excitation filter group corresponds to a filter wheel (with a blank lens stop) and is connected to a control system, allowing switching according to experimental requirements. The light is then scanned into a plane by a linear scanning galvanometer for animal fundus scanning, and further scanned by a dichroic mirror, where the dichroic mirror reflects the excitation light. The emitted light passes through a semi-transparent mirror and a focusing system to reach the eye of the animal being tested. The reflected light then passes sequentially through the focusing system, the semi-transparent mirror, a dichroic mirror, a set of reflective filters (with a blank lens stop at the rotating wheel), and a focusing lens to reach the imaging unit, thereby generating an angiographic image of the animal's fundus. The dichroic mirror allows the emitted light generated by the fluorescent substance that excites the fundus of the animal to pass through. Similarly, the set of emission filters corresponds to the filter rotating wheel and is connected to the control system, which can be switched according to experimental requirements. The function of the emission filters is to allow only the wavelength of light emitted by the fundus fluorescent agent to pass through, further filtering the excitation light, thereby generating a clear angiographic image of the animal's fundus.

[0047] The light source for a single-wavelength optical excitation system is a laser or a single-wavelength LED.

[0048] It can switch between different excitation light by switching between different lasers and single-wavelength LED light sources, thus eliminating the need for an excitation filter. The advantage of this method is that it has good wavelength monochromaticity and can reduce the influence of stray light. (Special note: The filter group can be a filter or a device with filtering effect such as a liquid crystal tunable filter).

[0049] In practice, the control system 8 includes a host computer and a microcontroller. The host computer sends the position information, angle information and compensation amount to the microcontroller through USB serial communication. The microcontroller then controls the electric adjustment platform 1 and the electric adjustment platform 6 of the OCT equipment to perform corresponding movements.

[0050] To enable intuitive visualization of the detection process, a display system 9 is also included. The display system 9 is electrically connected to the data processing system 7 and is used for focusing process and scanning image display.

[0051] The present invention also discloses an automatic alignment method for animal ophthalmic OCT based on the above-mentioned examination device, which includes the following steps: S1: The automatic recognition system acquires a three-dimensional image of the animal, identifies the position of the animal's head, and controls the electric adjustment platform of the OCT device to move the animal's head to the center of the field of view. S2: The data processing system further identifies the pupil position of the animal's eye, and controls the movement of the electric adjustment stage of the OCT device and the tilting of the electric adjustment platform through the control system, so that the pupil of the detected eye moves to the center of the field of view. S3: Identify the direction of the optical axis of the eyeball and control the deflection angle of the electric adjustment stage to make the OCT scanning beam coaxial with the optical axis of the eyeball; S4: Perform OCT optical path calibration by moving the corner bevel prism to make the optical path of the sample arm and the reference arm consistent. S5: The focusing system automatically adjusts the focal length according to the clarity of the fundus image, and further refines the focus according to the clarity of the OCT tomographic image; S6: Real-time eye movement tracking; the control system controls the electric adjustment platform of the OCT device to dynamically compensate for micro-displacements caused by nystagmus, breathing or heartbeat, so as to achieve eye tracking and alignment maintenance. S7: Start the OCT system to scan and generate a tomographic image of the animal's eye.

[0052] The apparatus and methods disclosed in the embodiments are described simply because they correspond to the methods disclosed in the embodiments. For relevant details, please refer to the method section.

[0053] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An OCT-based animal ophthalmic examination device, characterized in that, include: An electrically adjustable platform (1) is used to support animals and adjust their position. OCT system (2) is used to acquire tomographic images of the eyes of animals; The focusing system (3) is located between the electric adjustment stage (1) and the OCT system (2) and is used to achieve adaptive focusing between the scanning beam of the OCT system (2) and the animal's eyeball; A semi-transparent mirror (4) is located in the optical path between the OCT system (2) and the focusing system (3); An automatic identification system (5) is located on the reflected light path of the semi-transparent mirror (4) and is used to acquire images of the animal's eyes and identify the position of the eyeball and the direction of the optical axis. The electric adjustment table (6) of the OCT equipment is used to support the OCT system (2) and adjust the spatial position of the OCT probe; The data processing system (7) is used to process image data and control the alignment process; The control system (8) is connected to the data processing system (7), the electric adjustment platform (6) of the OCT equipment, the focusing system (3), the automatic identification system (5), the OCT system (2) and the electric adjustment platform (1) respectively by electrical signals, and can automatically control the movement and focusing of each system according to the feedback of the data processing system.

2. The animal ophthalmological examination device based on OCT according to claim 1, characterized in that, The electrically adjustable platform (1) is a servo motor-controlled rotary table, and the table surface of the rotary table is used to support the animal to be tested.

3. The animal ophthalmological examination device based on OCT according to claim 1, characterized in that, The OCT system (2) includes: a light source (21), an optical fiber coupler (22), a reference arm (23), a sample arm (24), and a spectrometer (25). The reference arm (23) includes a second collimating lens (231), a second lens (232), and a reflector (233). The sample arm (24) includes a third collimating lens (241), a corner prism (242), a first scanning galvanometer (243), and a second scanning galvanometer (244). The spectrometer (25) includes a first collimating lens (251), a grating (252), a first lens (253), and a linear camera (254); The sample light detected by the sample arm and the reference light detected by the reference arm interfere in the fiber optic coupler. The interference light is received by the spectrometer and transmitted to the data processing system to generate a tomographic image of the animal's eye.

4. The animal ophthalmological examination device based on OCT according to claim 3, characterized in that, The corner prism (242) serves as an optical extension line, and its position is controlled by the linear motor driven by the control system (8) to adjust the optical path of the sample light to be consistent with that of the reference light.

5. The animal ophthalmological examination device based on OCT according to claim 1, characterized in that, The automatic identification system (5) includes: an illumination source (51), a cylindrical mirror (52), a line scanning galvanometer (53), an intensity beam splitter (54), and an area array camera (55); the light emitted by the illumination source (51) is focused by the cylindrical mirror (52), then becomes two-dimensional scanning light by the line scanning galvanometer (53), and reaches the animal's eye after passing through the intensity beam splitter (54), the semi-transparent mirror (4), and the focusing system (3); the reflected light reaches the area array camera (55) for imaging after passing through the focusing system (3), the semi-transparent mirror (4), the intensity beam splitter (54), and the focusing lens.

6. The animal ophthalmological examination device based on OCT according to claim 1, characterized in that, The focusing system (3) is a combination of a 4F focusing system (32) and a zoom electronically tuned lens (31).

7. The animal ophthalmological examination device based on OCT according to claim 1, characterized in that, The electric adjustment platform (6) of the OCT equipment is a six-axis displacement adjustment platform, and the OCT probe of the OCT system (2) is set on the platform of the electric adjustment platform (6) of the OCT equipment.

8. The animal ophthalmological examination device based on OCT according to claim 5, characterized in that, It also includes a fluorescence detection system, which is implemented by the control system (8) switching the dichroic mirror and filter wheel in the automatic recognition system (5) to generate angiographic images of animal fundus angiography.

9. The animal ophthalmological examination device based on OCT according to claim 8, characterized in that, The fluorescence detection system is divided into a white light combined with a filter system and a single-wavelength light excitation system based on the difference in light source; the light source of the white light combined with a filter system is a white LED or a xenon lamp, and the light source of the single-wavelength light excitation system is a laser or a single-wavelength LED.

10. An OCT-based animal ophthalmic examination device according to claim 1, characterized in that, The control system (8) includes a host computer and a microcontroller. The host computer sends position information, angle information and compensation amount to the microcontroller through USB serial communication. The microcontroller controls the electric adjustment platform (1) and the electric adjustment platform (6) of the OCT equipment to perform corresponding movements.

11. The animal ophthalmological examination device based on OCT according to claim 1, characterized in that, It also includes a display system (9), which is electrically connected to the data processing system (7) for focusing and displaying scanned images.

12. An automatic alignment method for animal ophthalmic OCT based on the examination device according to any one of claims 1-11, characterized in that, Includes the following steps: S1: The automatic recognition system acquires a three-dimensional image of the animal, identifies the position of the animal's head, and controls the electric adjustment platform of the OCT device to move the animal's head to the center of the field of view. S2: The data processing system further identifies the pupil position of the animal's eye, and controls the movement of the electric adjustment stage of the OCT device and the tilting of the electric adjustment platform through the control system, so that the pupil of the detected eye moves to the center of the field of view. S3: Identify the direction of the optical axis of the eyeball and control the deflection angle of the electric adjustment stage to make the OCT scanning beam coaxial with the optical axis of the eyeball; S4: Perform OCT optical path calibration by moving the corner bevel prism to make the optical path of the sample arm and the reference arm consistent. S5: The focusing system automatically adjusts the focal length according to the clarity of the fundus image, and further refines the focus according to the clarity of the OCT tomographic image; S6: Real-time eye movement tracking; the control system controls the electric adjustment platform of the OCT device to dynamically compensate for micro-displacements caused by nystagmus, breathing or heartbeat, so as to achieve eye tracking and alignment maintenance. S7: Start the OCT system to scan and generate a tomographic image of the animal's eye.

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