Fundus imaging system

Abstract

The present application provides a fundus imaging system, wherein a pupil separator is used in the fundus imaging system. An illumination beam is reflected from the surface of a first pupil separator element to the human eye and then reflected from the fundus. The beam reflected from the fundus is scanned and emitted to form parallel light in different directions within the scanning range. Multi-angle parallel light symmetrically centered on the main optical axis enters the pupil separator and exits through the first pupil of the first pupil separator element and the second pupil of the second pupil separator element, entering a camera for imaging. The two beams of parallel light symmetrically incident about the main optical axis have the same diameter of the light spot after exiting the pupil separator, resulting in uniform light intensity across the entire field of view and consistent numerical apertures in different fields of view. This improves the uniformity of the light spot, resulting in more consistent clarity at all locations in the image formed and better image quality.

Description

Technical Field

[0001] The present application relates to the field of optical imaging technology, and in particular to a fundus imaging system. Background Art

[0002] Fundus imaging is an important clinical diagnosis and treatment basis in the field of ophthalmic disease diagnosis and treatment, used to detect eye conditions to obtain test data and support the diagnosis and treatment of ophthalmic diseases.

[0003] In existing fundus imaging systems, the pupil separator is typically a planar optical element with an elliptical outer profile. The central strip along the major axis of the pupil separator serves as an extinction zone to absorb light beams. A through-hole is provided in the center of the extinction zone as a light-transmitting zone to collect the light beams. The central strip is flanked by reflective zones. The pupil separator is positioned at a 45-degree angle within the main optical path of the fundus imaging system. The illumination beam is reflected by the reflective zone of the pupil separator before turning to enter the eye. After reflecting off the fundus, it re-enters the pupil separator, passing through the light-transmitting zone of the pupil separator before exiting and being captured by a camera to generate a fundus image.

[0004] Due to the tilted setting structure of the pupil separator, the numerical apertures of parallel light beams in different directions passing through the pupil separator are different, resulting in uneven light beams on both sides of the light-transmitting area of ​​the central through hole. This makes the clarity on both sides of the field of view of the fundus imaging system inconsistent, thus affecting the poor image quality of the fundus imaging. Summary of the Invention

[0005] The present application provides a fundus imaging system, including an adjustable pupil separator arranged in the fundus imaging system, which can make the light intensity of the entire field of view uniform, the numerical aperture in different fields of view consistent, and the quality of the imaged image better.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of the present application are as follows:

[0007] An embodiment of the present application provides a fundus imaging system, including a pupil separator, which includes a first pupil separation element and a second pupil separation element arranged at an angle, the first pupil separation element being provided with a first pupil hole, and the second pupil separation element being provided with a second pupil hole, wherein parallel light beams scanned in different directions are emitted through the first pupil hole of the first pupil separation element and the second pupil hole of the second pupil separation element, wherein the two beams of parallel light symmetrically incident about the main optical axis have the same spot diameter after being emitted from the pupil separator.

[0008] The beneficial effects of the embodiments of the present application include: the fundus imaging system provided by the embodiments of the present application includes a pupil separator, the pupil separator includes a first pupil separator element and a second pupil separator element arranged at an angle, the first pupil separator element is provided with a first pupil hole, the second pupil separator element is provided with a second pupil hole, parallel light beams of different directions scanned and emitted are emitted through the first pupil hole of the first pupil separator element and the second pupil hole of the second pupil separator element, wherein the diameters of the light spots of the two beams of parallel light beams symmetrically incident with the main optical axis as the center are the same after being emitted from the pupil separator. The pupil separator of the embodiment of the present application is applied to the fundus imaging system, the illumination light beam is reflected from the surface of the first pupil separator element to the human eye and then reflected by the fundus, the light beam reflected from the fundus is scanned and emitted to form parallel light beams of different directions within the scanning range, the parallel light beams of multiple angles symmetrical with the main optical axis as the center enter the pupil separator, and are sequentially emitted through the first pupil hole of the first pupil separator element and the second pupil hole of the second pupil separator element to be imaged by the incident camera. Among them, the two beams of parallel light symmetrically incident with the main optical axis as the center have the same diameter of the light spot after being emitted through the pupil separator, so that the light intensity of the entire field of view is uniform, the numerical aperture in different fields of view is consistent, the uniformity of the light spot is improved, the clarity of the image formed is more consistent, and the quality of the image is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0010] Figure 1 This is one of the optical path schematic diagrams of a pupil separator in a fundus imaging system provided in an embodiment of the present application;

[0011] Figure 2 This is a second optical path schematic diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application;

[0012] Figure 3 This is a third optical path diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application;

[0013] Figure 4 This is a fourth optical path diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application;

[0014] Figure 5 This is a fifth optical path diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application;

[0015] Figure 6 A schematic structural diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application;

[0016] Figure 7 The sixth optical path diagram of a pupil separator in a fundus imaging system provided in an embodiment of the present application;

[0017] Figure 8 A schematic diagram of the optical path of a fundus imaging system provided in an embodiment of the present application.

[0018] Icon: 01- pupil separator; 02- scanning galvanometer; 03- camera; 10- first pupil separation element; 11- first pupil; 20- second pupil separation element; 21- second pupil; 30- receiving substrate; d0- diameter of the second pupil; d1, d2- diameters of the light spots after the two beams of parallel light symmetrically incident with the main optical axis as the center are emitted through the pupil separator; α- angle between the first pupil separation element and the second pupil separation element; θ- angle between the two beams of parallel light symmetrically incident with the main optical axis as the center. DETAILED DESCRIPTION

[0019] To make the purpose, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. It should be noted that, in the absence of conflict, the various features in the embodiments of the present application can be combined with each other, and the combined embodiments are still within the scope of protection of the present application.

[0020] In the description of this application, it should be noted that the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are used solely to facilitate and simplify the description of this application. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third," etc., are used solely for distinction and description and should not be construed as indicating or implying relative importance.

[0021] In one aspect of an embodiment of the present application, a fundus imaging system is provided, including a pupil separator, such as Figure 1 As shown, the pupil separator includes a first pupil separation element 10 and a second pupil separation element 20 arranged at an angle. The first pupil separation element 10 is provided with a first pupil hole 11, and the second pupil separation element 20 is provided with a second pupil hole 21. Parallel light scanned in different directions is emitted through the first pupil hole 11 of the first pupil separation element 10 and the second pupil hole 21 of the second pupil separation element 20. The two beams of parallel light symmetrically incident with the main optical axis as the center have the same diameter of the light spot after being emitted from the pupil separator.

[0022] like Figure 1 As shown, the pupil separator includes two optical parts: a first pupil separation element 10 and a second pupil separation element 20. Along the light propagation direction of the main optical axis, the first pupil separation element 10 is in front and the second pupil separation element 20 is in the back. The first pupil separation element 10 and the second pupil separation element 20 are connected and arranged at a preset angle.

[0023] The parallel light beams of different directions are scanned and emitted toward the pupil separator. They sequentially pass through the first pupil 11 of the first pupil separation element 10 and the second pupil 21 of the second pupil separation element 20 before being emitted. The light beams incident on the surface of the first pupil separation element 10 are reflected, and the light beams incident on the surface of the second pupil separation element 20 after passing through the first pupil 11 of the first pupil separation element 10 are also absorbed. Thus, the parallel light beams of different directions, after passing through the first pupil 11 and the second pupil 21, still emit in the original parallel light direction. However, due to the restrictions imposed by the first pupil 11 and the second pupil 21 on the outer contour of the transmitted light beams, as shown in FIG. Figure 1 As shown, two parallel light beams incident symmetrically about the principal optical axis are compared. After exiting through the first pupil aperture 11 and the second pupil aperture 21, the two parallel light beams have received spot diameters d1 and d2, respectively, which are identical. A pupil separator with this structural design effectively ensures that within a certain range of incident angles, the numerical aperture of the spot exiting the pupil separator for parallel light from different directions remains consistent. This provides stable beam modulation conditions for the pupil separator to achieve superior imaging quality when deployed in a fundus imaging system.

[0024] Among them, the setting position and shape of the first pupil 11 on the first pupil separation element 10, the setting position and shape of the second pupil 21 on the second pupil separation element 20, and the specific angle between the first pupil separation element 10 and the second pupil separation element 20 are not strictly limited in the embodiments of the present application. Those skilled in the art can reasonably set them according to the parameter conditions of the incident light beam and the parameter requirements of the output light beam.

[0025] The pupil separator provided in an embodiment of the present application includes a first pupil separation element 10 and a second pupil separation element 20 arranged at an angle. The first pupil separation element 10 is provided with a first pupil aperture 11, and the second pupil separation element 20 is provided with a second pupil aperture 21. Parallel light beams emitted in different directions are scanned and emitted sequentially through the first pupil aperture 11 of the first pupil separation element 10 and the second pupil aperture 21 of the second pupil separation element 20. The two beams of parallel light beams incident symmetrically about the principal optical axis have the same diameter as the light spot after exiting the pupil separator. The pupil separator of the embodiment of the present application is applied to a fundus imaging system. The illumination beam is reflected from the surface of the first pupil separation element 10 to the human eye and then reflected by the fundus. The beam reflected from the fundus is scanned and emitted to form parallel light beams in different directions within the scanning range. The parallel light beams at multiple angles symmetrically about the principal optical axis enter the pupil separator and sequentially exit through the first pupil aperture 11 of the first pupil separation element 10 and the second pupil aperture 21 of the second pupil separation element 20 to be imaged by a camera. Among them, the two beams of parallel light symmetrically incident with the main optical axis as the center have the same diameter of the light spot after being emitted through the pupil separator, so that the light intensity of the entire field of view is uniform, the numerical aperture in different fields of view is consistent, the uniformity of the light spot is improved, the clarity of the image formed is more consistent, and the quality of the image is better.

[0026] In some feasible implementations of the present application, such as Figure 2 As shown, the angle α between the first pupil separation element 10 and the second pupil separation element 20 is 45°, the first pupil separation element 10 is 45° to the main optical axis, and the second pupil separation element 20 is perpendicular to the main optical axis.

[0027] like Figure 2As shown, the pupil separator of the embodiment of the present application is arranged in the optical path to modulate the light beam. The angle α between the first pupil separator element 10 and the second pupil separator element 20 is 45°. If the second pupil separator element 20 is arranged perpendicular to the principal optical axis, the angle between the first pupil separator element 10 and the principal optical axis is also 45°. When the pupil separator of the embodiment of the present application is arranged in a fundus imaging system, the light beam reflected from the fundus is scanned and emitted, forming parallel light beams in different directions within the scanning range. The parallel light beams are incident on the pupil separator at multiple angles symmetrically about the principal optical axis. The two parallel light beams incident symmetrically about the principal optical axis are emitted after passing through the first pupil aperture 11 and the second pupil aperture 21. The diameters d1 and d2 of the two emitted light beams are equal. The two beams of parallel light that are symmetrically incident with the main optical axis as the center can achieve the same diameter of the symmetrically emitted light beams after passing through the pupil separator, which can make the light intensity of the entire field of view uniform and improve the uniformity of the light spot emitted through the pupil separator. Therefore, when the pupil separator of the embodiment of the present application is applied to the fundus imaging system and is set corresponding to the main optical axis in the above manner, the clarity of the image received in the camera of the fundus imaging system can be more consistent at all places, and the imaging quality is better.

[0028] In some feasible implementations of the present application, such as Figure 3 As shown, the second pupil separation element 20 is arranged on a plane where the intersection of two parallel light beams symmetrically incident with the main optical axis and the main optical axis is located.

[0029] Reference Figure 3 As shown, Figure 3 The figure shows two parallel light beams incident symmetrically about the principal optical axis, each at the same angle to the principal optical axis. After the two parallel light beams are incident, they intersect and then emerge. The second pupil separation element 20 of the pupil separator is positioned at the plane where the intersection of the two parallel light beams is located. This ensures that the two paired parallel light beams incident at the same angle on either side of the principal optical axis have the same diameter when they emerge from the pupil separator. When the pupil separator of the embodiment of the present application is used in a fundus imaging system, the numerical apertures of the symmetrical fields of view of the light beams emitted by the pupil separator are consistent when they reach the camera, resulting in a higher quality fundus image.

[0030] In some feasible implementations of the present application, such as Figure 4 As shown, the pupil separator further includes a receiving substrate 30, and the bottoms of the first pupil separation element 10 and the second pupil separation element 20 are respectively fixed to the two side edges of the receiving substrate 30, wherein the first pupil separation element 10 is at a 45° angle to the receiving substrate, and the second pupil separation element 20 is perpendicular to the receiving substrate 30; the center of the first pupil 11 of the first pupil separation element 10 and the center of the second pupil 21 of the second pupil separation element 20 are both located on the principal optical axis.

[0031] like Figure 4 As shown, the pupil separator further includes a receiving substrate 30 connected to the first pupil separation element 10 and the second pupil separation element 20, respectively. The receiving substrate 30 accurately fixes the first pupil separation element 10 and the second pupil separation element 20 at a specific angular relationship, so that the pupil separator of the embodiment of the present application is easy to set up and fine-tune in a working optical path, such as a fundus imaging system.

[0032] The arrangement structure of the receiving substrate 30 and the first pupil separation element 10 and the second pupil separation element 20 includes a variety of specific structural design schemes. For example, in some feasible embodiments of the present application, still refer to Figure 4 As shown, the top of the first pupil separation element 10 is connected to the top of the second pupil separation element 20. Thus, the first pupil separation element 10 having the first pupil aperture 11 and the second pupil separation element 20 having the second pupil aperture 21 can be designed and manufactured separately. The first and second pupil separation elements 10 and 20 can then be placed on the receiving substrate 30 and the top of the second pupil separation element 20 connected. This makes the installation, commissioning, and calibration process smooth, convenient, and easy to operate.

[0033] In addition, in other feasible embodiments of the present application, such as Figure 5 As shown, there is a preset interval between the top of the second pupil separation element 20 and the upper edge of the first pupil 11 of the first pupil separation element 10. The space between the top of the second pupil separation element 20 and the upper edge of the first pupil 11 of the first pupil separation element 10 serves as the second pupil 21 of the second pupil separation element 20, and the preset interval is the diameter of the second pupil 21.

[0034] like Figure 5As shown, in this design, the portion of the first pupil separation element 10 above the first pupil 11 is shared with the second pupil separation element 20, making the overall pupil separation device more compact and effectively reducing the optical axis. When the pupil separation device of the present embodiment is used in an optical path system, it is more flexible in miniaturized optical devices. In this embodiment, the second pupil separation element 20 can be understood as a single plate structure. The light-receiving surface of the plate structure is capable of absorbing light. For example, the light-receiving surface of the plate structure is coated with a black or dark color, and light impinging on the light-receiving surface of the plate structure is absorbed. The vertical space between the top of the second pupil separation element 20 and the upper edge of the first pupil 11 serves as the second pupil 21. In this way, the upper ends of two parallel light beams incident symmetrically about the principal optical axis and having the same angle with the principal optical axis are blocked by the upper edge of the first pupil 11 as a boundary, and the lower ends of the two parallel light beams are blocked by the lower edge of the second pupil 21, that is, the end of the second pupil separation element 20 as a boundary. The two parallel beams of light emitted in this way have the same diameter.

[0035] like Figure 6 As shown, in the pupil separator of the embodiment of the present application, the second pupil separator 20 is hingedly connected to the first pupil separator 10. A support structure for connecting and fixing to the framework of a fundus imaging system is extended from one end of the first pupil separator 10. The support structure secures the pupil separator in the fundus imaging system. The first pupil separator 10 includes a reflective sheet having a hollow portion. The hollow portion of the reflective sheet forms a first pupil aperture 11, which serves as the first pupil separator 10. Hinge axes are provided on opposite sides of the hollow portion of the reflective sheet, located in the plane of the reflective sheet. The second pupil separator 20 is hingedly mounted within the hollow portion via the hinge axes. A second pupil aperture 21 of a predetermined diameter is formed in the center of the second pupil separator 20. Due to the hinged connection between the second pupil separator 20 and the first pupil separator 10, the second pupil separator 20 can rotate relative to the first pupil separator 10 about the hinge axis, thereby adjusting the angle between the second pupil separator 20 and the first pupil separator 10.

[0036] Please refer to Figure 7 As shown, the angle between the first pupil separation element 10 and the second pupil separation element 20 is adjusted to a preset angle. Two beams of parallel light symmetrically incident with the main optical axis and having the same angle with the main optical axis cross and then emerge. The first pupil 11 and the second pupil 21 cross and partially overlap. The two beams of parallel light are constrained by the first pupil separation element 10 and the second pupil separation element 20 respectively, wherein part of the beams that can pass through the first pupil 11 and the second pupil 21 emerge. In this way, two pairs of parallel light beams incident at the same angle along the two sides of the main optical axis are symmetrically incident. Figure 7The diameters of the light beams emitted after the pupil separator are the same. When the pupil separator of the embodiment of the present application is used in a fundus imaging system, the numerical apertures of the light beams emitted through the pupil separator are consistent when they reach the camera, resulting in a better quality fundus image.

[0037] And refer to Figure 6 It can be seen that in the pupil separator scheme of the present embodiment, the angle between the first pupil separation element 10 and the second pupil separation element 20 can be conveniently adjusted and fixed by a hinge axis. By adjusting the different angles between the first pupil separation element 10 and the second pupil separation element 20, the fundus imaging system to which the pupil separator of the embodiment of the present application is applied can more flexibly match the requirements of two pairs of parallel light beams incident at the same specific angle in different scenes, and both can be emitted as light beams of the same diameter, so that the pupil separator of the embodiment of the present application can be applied to fundus imaging systems with a variety of different parameter conditions through simple adjustment and fixation, and is easy to operate and has high precision.

[0038] Another aspect of the embodiment of the present application provides a fundus imaging system, comprising any of the aforementioned pupil separators. The illumination light beam is reflected from the surface of the first pupil separation element 10 to the human eye, and then reflected from the fundus. The light beam reflected from the fundus is scanned and emitted to form parallel light in different directions within the scanning range. The multi-angle parallel light symmetrically centered on the main optical axis enters the pupil separator, and sequentially passes through the first pupil 11 of the first pupil separation element 10 and the second pupil 21 of the second pupil separation element 20, and then converges to the camera for imaging. Among them, the two beams of parallel light symmetrically incident with the main optical axis as the center have the same diameter after exiting the pupil separator, so that the light intensity of the entire field of view is uniform, the numerical aperture is consistent in different fields of view, the uniformity of the light spot is improved, the clarity of the image is relatively consistent, and the quality of the image is better. It provides a clearer and more accurate image basis for the diagnosis and treatment of ophthalmic diseases. Thus, it can provide a clearer and more accurate image basis for the diagnosis and treatment of ophthalmic diseases.

[0039] In some feasible implementations of the present application, such as Figure 8 As shown, the fundus imaging system includes a pupil separator 01, a scanning galvanometer 02 and a camera 03. The light beam reflected by the fundus is scanned and emitted by the scanning galvanometer 02, and multi-angle parallel light symmetrical with the main optical axis is incident on the pupil separator 01 and incident on the camera 03 to form an image.

[0040] like Figure 8As shown, the fundus imaging system of the embodiment of the present application includes a scanning galvanometer 02, a pupil separator 01 and a camera 03. In front of the scanning galvanometer 02 and the camera 03, a scanning lens group and an imaging lens group for modulating the incident light path are also included. In some feasible embodiments of the present application, the fundus imaging system also includes an illumination module ( Figure 8 (not shown in the figure), the lighting module includes a light source, an optical unit for collimating, focusing and uniformly modulating the light beam emitted by the light source, and an aperture for contour constraining the emitted light beam. For example, the wavelength range of the light beam emitted by the light source is between 400nm and 900nm, the focal length range of the collimating lens is set between 6mm and 30mm, and the focal length range of the focusing unit is set between 20mm and 100mm, wherein the optical unit for uniform light modulation can adopt optical elements such as optical fiber bundles, rectangular quartz rods, and scattering plates. The light beam emitted by the light source is uniformly modulated and then emitted through the aperture, and the setting position of the aperture is conjugate with the fundus to be measured. The aperture described here is an illumination aperture, which is usually rectangular. This application provides waist drum-shaped apertures and stepped apertures. The light beam exiting the aperture is collimated and then reflected by the surface of the pupil separator to the scanning galvanometer 02. It then passes through the scanning lens group and is converged by the eyepiece group to the position of the human eye's pupil, illuminating the fundus, forming a rectangular illumination spot at the fundus and performing a wide-line illumination scan of the fundus under test. The return light signal scattered from the fundus passes through the pupil to the eyepiece group, and after passing through the eyepiece group, it is reflected by the dichroic mirror to the scanning lens group. The light beam emitted from the scanning lens group is scanned by the scanning galvanometer 02 and then exits the pupil separator 01. The light beam emitted from the light-transmitting portion at the center of the pupil separator 01 is converged by the imaging lens group to the camera 03. The fundus and camera 03 are in a conjugate relationship. In this way, it can be ensured that the light signal returning through the fundus, after passing through the light-transmitting part in the center of the pupil separator 01, that is, the first pupil 11 of the first pupil separation element 10 and the second pupil 21 of the second pupil separation element 20, the structure that serves as an aperture to constrain the profile of the outgoing light beam is located at the intersection of the light beams at the same symmetrical angles. This can ensure that the diameters of the light beam spots at symmetrical angles on both sides centered on the main optical axis are the same. After the light beams at symmetrical angles reach the camera 03, the numerical apertures are consistent in the symmetrical fields of view, thereby making the image quality of the camera 03 more uniform and clear, and the imaging quality is better.

[0041] In some feasible implementations of this application, please refer to Figure 5 As shown, the light beam formed in the camera 03 satisfies the following relationship:

[0042] d2=d1=d0*cos(θ / 2)(1);

[0043] Wherein, d1 and d2 are the diameters of the light spots of the two parallel light beams incident symmetrically with the main optical axis as the center after exiting the pupil separator 01, d0 is the diameter of the second pupil 21, and θ is the angle between the two parallel light beams incident symmetrically with the main optical axis as the center.

[0044] like Figure 5 As shown, the pupil separator 01 of the embodiment of the present application is set in the fundus imaging system. The centers of the first pupil 11 and the second pupil 21 of the pupil separator 01 are both located on the main optical axis, and the second pupil separation element 20 is set at the plane where the focus of two beams of parallel light symmetrically incident with the main optical axis and having the same angle with the main optical axis is located. The diameter d0 of the second pupil 21 is located at the intersection of the two beams of parallel light. The angle between the two beams of parallel light symmetrically incident with the main optical axis is θ, then the imaging light beam emitted from the pupil separator 01 to the camera 03 satisfies the relationship (1), that is, under the premise that the numerical aperture of the light beam when reaching the camera 03 is consistent in the symmetrical field of view, it can also make the light flux in the optical path system as high as possible.

[0045] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A fundus imaging system, comprising a pupil separator, characterized in that: The pupil separator includes a first pupil separation element and a second pupil separation element arranged at an angle. The first pupil separation element is provided with a first pupil hole, and the second pupil separation element is provided with a second pupil hole. Parallel light beams scanned in different directions are emitted through the first pupil hole of the first pupil separation element and the second pupil hole of the second pupil separation element. The two beams of parallel light symmetrically incident with the main optical axis as the center have the same diameter of the light spot after being emitted from the pupil separator.

2. The fundus imaging system according to claim 1, wherein: The angle between the first pupil separation element and the second pupil separation element is 45°, the first pupil separation element is 45° to the main optical axis, and the second pupil separation element is perpendicular to the main optical axis.

3. The fundus imaging system according to claim 2, wherein: The second pupil separation element is arranged on a plane where the intersection of two parallel light beams symmetrically incident with the main optical axis and the main optical axis is located.

4. The fundus imaging system according to claim 2, wherein: The pupil separator also includes a receiving substrate, and the bottoms of the first pupil separation element and the second pupil separation element are respectively fixed to the two side edges of the receiving substrate, wherein the first pupil separation element is at a 45-degree angle to the receiving substrate, and the second pupil separation element is perpendicular to the receiving substrate; the first pupil center of the first pupil separation element and the second pupil center of the second pupil separation element are both located on the main optical axis.

5. The fundus imaging system according to claim 4, characterized in that: The top of the first pupil separation element is connected to the top of the second pupil separation element.

6. The fundus imaging system according to claim 4, characterized in that: There is a preset interval between the top of the second pupil separation element and the upper edge of the first pupil of the first pupil separation element. The space between the top of the second pupil separation element and the upper edge of the first pupil of the first pupil separation element serves as the second pupil of the second pupil separation element, and the preset interval is the diameter of the second pupil.

7. The fundus imaging system according to claim 1, wherein: The pupil separator also includes a support structure for being fixedly connected to the frame structure of the fundus imaging system. The first pupil separation element is fixedly connected to the support structure. The first pupil separation element includes a reflective sheet having a hollow portion. The hollow portion of the reflective sheet serves as a first pupil of the first pupil separation element. Hinge axes located in the plane where the reflective sheet is located are provided on opposite sides of the hollow portion of the reflective sheet. A second pupil separation element is hingedly provided in the hollow portion via the hinge axes. A second pupil of a preset diameter is formed in the center of the second pupil separation element.

8. The fundus imaging system according to any one of claims 1 to 7, characterized in that: The fundus imaging system also includes a scanning galvanometer and a camera. The light beam reflected by the fundus is scanned and emitted by the scanning galvanometer, and is incident on the pupil separator as parallel light with multiple angles symmetrical with the main optical axis, and then incident on the camera for imaging.

9. The fundus imaging system according to claim 8, characterized in that: The light beam imaged in the camera satisfies the following relationship: d2=d1=d0*cos(θ / 2); Wherein, d1 and d2 are the diameters of the light spots of two parallel light beams incident symmetrically with the main optical axis as the center after exiting the pupil separator, d0 is the diameter of the second pupil, and θ is the angle between the two parallel light beams incident symmetrically with the main optical axis as the center.

10. The fundus imaging system according to claim 8, wherein: It also includes an illumination module, which emits an illumination beam toward the pupil separator. The illumination beam is reflected by the surface of the first pupil separation element to the human eye and then reflected by the fundus.

Images