Rotating parabolic fundus imaging system and imaging method

Abstract

The application relates to the technical field of fundus imaging, in particular to a rotating parabolic fundus imaging system and an imaging method, the imaging system comprising a light detection module, a light source module, a light splitting module, a scanning module, an amplification module and a parabolic reflection module; the parabolic reflection module comprises at least one group of parabolic mirrors; each group of parabolic mirrors comprises a pair of parabolic concave mirrors, the focal points of each parabolic concave mirror fall on the optical axis of the amplification module, the focal points of any two adjacent groups of parabolic mirrors coincide, and the conjugate planes where the focal points at the two ends are located are the real entrance pupil of the amplification module and the pupil of the human eye respectively; the parabolic mirrors and the scanning module are rotatably arranged at 360 degrees with the optical axis of the amplification module as the rotation axis. The application has the effects of realizing ultra-wide-angle fundus imaging under a long working distance, the system giving consideration to high resolution and free pupil dilation, the full field of view being free of field of view loss, and the full field of view optical resolution reaching 15 um.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fundus imaging, in particular to a rotating parabolic fundus imaging system and imaging method. BACKGROUND

[0002] Fundus photography is a routine project of ophthalmic examination. Common fundus imaging examination methods include fundus ultrasonography, fundus fluorescence angiography, optical coherence tomography examination, etc., which can help doctors to check diseases of fundus structures such as pupil and choroid, and also has a guiding effect on the diagnosis of some systemic diseases such as hypertension and diabetes.

[0003] At present, fundus cameras mainly have two structures of transmission type and reflection type. The transmission type system has the advantages of high resolution, simple structure, small system volume, etc., but due to the limitation of working distance, the field of view angle of the transmission type fundus imaging system is limited, and the patient needs to dilate the pupil before examination, which will cause certain discomfort to the patient. The reflection type system utilizes the conjugate characteristics of the ellipsoidal mirror, and the light emitted by the laser is irradiated to the pupil through the scanning galvanometer, and the reflected light returns to the detector through the original path, thereby realizing long working distance and ultra-wide angle imaging, but the disadvantage is that the aspherical mirror will introduce large aberration, resulting in poor imaging quality, so the resolution of the reflection type fundus imaging system is usually inferior to that of the transmission type imaging system, and the processing and assembly of the large-diameter aspherical mirror have certain requirements.

[0004] A laser scanning fundus imaging device is disclosed in a related document, which adopts two pieces of parabolic mirrors with central through holes and different focal lengths to solve the problem of poor imaging quality of the traditional reflection type system, and has the characteristics of high resolution and excellent imaging quality.

[0005] According to the related technology in the above, there is a problem of missing full field of view imaging. SUMMARY

[0006] In order to solve the problem of missing full field of view imaging under the condition of high resolution, the purpose of the present application is to provide a rotating parabolic fundus imaging system and imaging method.

[0007] In the first aspect, the rotating parabolic fundus imaging system provided by the present application adopts the following technical scheme:

[0008] A rotating parabolic fundus imaging system, comprising a light detection module and a light source module, a light splitting module, a scanning module, an amplification module and a parabolic reflection module arranged in sequence along a first light path direction, wherein the light detection module is arranged in sequence along a second light path direction with the light splitting module as the starting point, and is used for receiving reflected light generated from a human eye and imaging;

[0009] The parabolic reflection module comprises at least one set of parabolic mirrors, which are sequentially and spacedly arranged along the optical axis direction of the magnification module.

[0010] Each set of parabolic mirrors comprises a pair of parabolic concave mirrors, which are arranged on both sides of the optical axis of the magnification module and oppositely arranged, the focal point of each parabolic concave mirror falls on the optical axis of the magnification module, and the focal points of any two adjacent sets of parabolic mirrors coincide, and the conjugate planes where the focal points at both ends are located are the real entrance pupil of the magnification module and the pupil of the human eye.

[0011] The at least one set of parabolic mirrors and the scanning module are rotatably arranged at 360° around the optical axis of the magnification module as the rotation axis.

[0012] By adopting the above technical solution, firstly, the parabolic reflection module, the scanning module and the magnification module are combined, the characteristics of the parabolic surface are utilized, the conjugation between the pupil of the human eye and the real entrance pupil of the magnification module is realized, the pupil of the human eye is "migrated" to the real entrance pupil of the magnification module, the super-wide-angle fundus imaging under a long working distance is realized, and the system takes into account high resolution and pupil-free; further, the parabolic reflection module is synchronously rotated at 360° with the scanning module, the linear field of view is converted into a full field of view, and there is no field of view missing, and the optical resolution of the full field of view reaches 15um.

[0013] Optionally, the light source module is one of a single-wavelength light source and a multi-wavelength light source.

[0014] By adopting the above technical solution, the light source module is selected according to the requirement, the multi-wavelength detection requirement is met, and the rotating parabolic fundus imaging system can solve the color distortion problem of the traditional ellipsoidal mirror for multi-wavelength imaging.

[0015] Optionally, the parabolic reflection module comprises 1-2 sets of parabolic mirrors.

[0016] By adopting the above technical solution, the number of parabolic mirror sets is set according to the requirement, and then the working distance is adjusted according to the requirement, and the application range is improved.

[0017] Optionally, the scanning module realizes 90° folding of the light.

[0018] By adopting the above technical solution, the scanning is realized while the packaging volume of the equipment is reduced.

[0019] Optionally, the magnification module comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens which are sequentially arranged along the first light path direction.

[0020] The first lens is a cemented lens, the first surface along the first light path direction is a concave surface, the curvature radius is set to 220-280mm, the second surface is a concave surface relative to the first surface, the curvature radius is set to 15-30mm, the third surface is a convex surface, the curvature radius is set to 80-120mm, the center thickness between the first surface and the second surface is 7-8mm, and the center thickness between the second surface and the third surface is 4-5mm.

[0021] The first surface of the second lens along the first light path direction is a convex surface, the curvature radius is set to -130--190mm, the second surface is a convex surface, the curvature radius is set to 40-70mm, and the center thickness is 7-9mm.

[0022] The first surface of the third lens along the first light path direction is a convex surface, the curvature radius is set to -15--35mm, the second surface is a concave surface, the curvature radius is set to -200--250mm, and the center thickness is 7-8mm.

[0023] The first surface of the fourth lens along the first light path direction is a convex surface, the curvature radius is set to -10--20mm, the second surface is a concave surface, the curvature radius is set to -20--40mm, and the center thickness is 8-10mm.

[0024] The first surface of the fifth lens along the first light path direction is a convex surface, the curvature radius is set to -5--15mm, the second surface is a convex surface, the curvature radius is set to 5-15mm, and the center thickness is 7-8mm.

[0025] By adopting the above technical scheme, the magnifying module has the advantages of small size and good imaging effect by designing the shapes of the lenses, setting the curvature radii and the center thicknesses, and cooperating the first lens with the scanning module and the fifth lens with the parabolic reflecting module.

[0026] Optionally, the gap between the second lens and the first lens is 35-45mm, the gap between the second lens and the third lens is 60-70mm, the gap between the third lens and the fourth lens is 3-8mm, and the gap between the fourth lens and the fifth lens is 3-8mm.

[0027] By adopting the above technical scheme, the gaps between the lenses of the magnifying module are further limited, and the imaging effect is improved.

[0028] Optionally, the magnifying module further comprises a refractive compensation device, which is movably arranged between the second lens and the third lens.

[0029] By adopting the above technical scheme, the refractive power adjusting device is arranged in the magnifying module, the position of the refractive power adjusting device is controlled by a mechanical structure, and when the refractive power adjusting device is adjusted for a refractive eye, only the refractive compensation lens group moves along the optical axis, and the total length of the lens group remains unchanged.

[0030] Optionally, the dioptric compensation device comprises a sixth lens and a seventh lens arranged in sequence along the first light path direction, and the gap between the sixth lens and the seventh lens is 3-8mm.

[0031] The first surface of the sixth lens along the first light path direction is a convex surface, and the curvature radius is set to-40--70mm; the second surface is a convex surface, and the curvature radius is set to 800-1200mm; and the center thickness is 4-5mm.

[0032] The first surface of the seventh lens along the first light path direction is a concave surface, and the curvature radius is set to 15-35mm; the second surface is a convex surface, and the curvature radius is set to 70-100mm; and the center thickness is 4-5mm.

[0033] The moving distance range of the dioptric compensation device relative to the third lens is 15-55mm.

[0034] By adopting the above technical scheme, the dioptric adjustment device can compensate for the human eye with a dioptric power of-20D to +20D.

[0035] Optionally, the rotating parabolic fundus imaging system further comprises an imaging lens group arranged between the light splitting module and the scanning module, used for converging the transmitted light passing through the light splitting module and converging to the scanning module.

[0036] By adopting the above technical scheme, light convergence is realized to improve the transmission effect of light.

[0037] In a second aspect, the rotating parabolic fundus imaging method provided by the present application adopts the following technical scheme:

[0038] A rotating parabolic fundus imaging method, comprising the rotating parabolic fundus imaging system, and the at least one group of parabolic mirrors and the scanning module are rotated 360° around the optical axis of the magnification module to perform fundus imaging.

[0039] By adopting the above technical scheme, an ultra-wide-angle fundus imaging method under long working distance is provided, which takes into account high resolution, pupil dilation-free, and full field of view without field of view loss, and the full field of view optical resolution reaches 15um.

[0040] In summary, the present application has at least one of the following beneficial technical effects:

[0041] 1. The system is composed of a rotatable parabolic concave mirror, a scanning module and a magnifying module, utilizes the characteristics of the parabolic mirror, realizes the conjugation between the pupil of the human eye and the real entrance pupil of the magnifying module, "migrates" the pupil of the human eye to the real entrance pupil of the magnifying module, realizes the super-wide-angle fundus imaging under a long working distance, and the system has high resolution, is free of mydriasis, has no field-of-view loss in the full field of view, and the optical resolution in the full field of view reaches 15 um.

[0042] 2. A diopter adjusting device is arranged in the magnifying module, the position of the diopter adjusting device is controlled by a mechanical structure, the diopter adjusting device can compensate the human eye with a diopter of -20D to +20D, and when the diopter adjusting device is adjusted for the human eye with a diopter, only the diopter compensation lens group moves along the optical axis, and the total length of the lens group remains unchanged.

[0043] 3. The rotatable parabolic concave mirror, the magnifying module and the human eye form a coaxial system, which is convenient for assembling and adjusting, and the parabolic concave mirror can further reduce the packaging volume of the equipment compared with the traditional large ellipsoidal mirror, and the overall occupied space is small. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 Fig. 1 is a schematic diagram of the system structure provided by the embodiment of the application;

[0045] Figure 2 Fig. 5 is a 45° side view of the structure of the parabolic reflection module and the magnifying module provided by the embodiment of the application;

[0046] Figure 3 Fig. 7 is a schematic diagram of the scanning mode of the linear field of view on the retina of the human eye;

[0047] Figure 4 Fig. 8 is a schematic diagram of the scanning mode of one complete scanning on the retina of the human eye;

[0048] Figure 5 Fig. 9 is an adjustment schematic diagram of the diopter compensation device in the magnifying module;

[0049] Figure 6 Fig. 10 is a full-field-of-view spot diagram of a 488nm wavelength;

[0050] Figure 7 Fig. 11 is a full-field-of-view spot diagram of a 520nm wavelength;

[0051] Figure 8 Fig. 12 is a full-field-of-view spot diagram of a 635nm wavelength;

[0052] Figure 9 Fig. 13 is a full-field-of-view spot diagram of a 785nm wavelength.

[0053] Explanation of reference signs: 1, light source module; 2, light splitting module; 3, imaging lens group; 4, scanning module; 5, magnification module; 6, parabolic reflection module; 7, human eye; 8, detector; 9, host computer; 501, first conjugate point; 502, refractive compensation device; 601, superimposed focal point; 701, pupil of human eye. DETAILED DESCRIPTION

[0054] The following description will be made in conjunction with the accompanying drawings. Figure 1 ~ accompanying drawings Figure 9 The present application will be further described in detail.

[0055] Example 1

[0056] Example 1 of the present application discloses a rotating parabolic fundus imaging system, referring to Figure 1 The rotating parabolic fundus imaging system comprises a light source module 1, a light splitting module 2, a scanning module 4, a magnification module 5, a parabolic reflection module 6, and a light detection module (detector 8, host computer 9).

[0057] The transmission path of light in the working process includes a first light path direction (incident route) and a second light path direction (return route), wherein the light source module 1, the light splitting module 2, the scanning module 4, the magnification module 5, and the parabolic reflection module 6 are sequentially arranged along the first light path direction, and the light detection module is sequentially arranged along the second light path direction starting from the light splitting module 2, for receiving reflected light generated from the human eye 7 and imaging.

[0058] I. Illumination along the first light path direction (incident route), including: the light source module 1 emits light, the light passes through the light splitting module 2, then sequentially enters the magnification module 5 and the parabolic reflection module 6 through the scanning module 4, and then reaches the human eye 7; Specifically, it can include:

[0059] 1.1, the light source module 1 is used to emit light as a light source to illuminate the pupil, in one embodiment, the light source module 1 is used to emit laser, the light source module 1 can select laser but is not limited to laser, Figure 1 The light source module 1 in the above embodiment only shows one light source, but the actual light source module 1 can be one of single-wavelength light source and multi-wavelength light source, that is, the light source module 1 can be a single-wavelength light source or a multi-wavelength light source; Taking the multi-wavelength light source as an example, different wavelengths of laser usually pass through a beam combiner to form a beam of light, which enters the light splitting module 2;

[0060] In one specific embodiment, the multi-wavelength light source emits light with wavelengths of 488nm, 520nm, 635nm, and 785nm, and the optical fiber passes through the beam combiner to form a beam of light, which enters the light splitting module 2;

[0061] In this embodiment, the light source module 1 is a single-wavelength laser light source with an emission wavelength of 488nm.

[0062] 1.2, the light splitting module 2 is used for receiving light from the light source module 1 and controlling the light to pass through the light splitting module 2 to the scanning module 4 in a certain proportion;

[0063] In an embodiment, the light splitting module 2 can be a beam splitter, or a beam splitter group, which can be a cubic beam splitter or a flat plate beam splitter according to actual needs;

[0064] In the embodiment, the light splitting module 2 is a beam splitter.

[0065] 1.3, the scanning module 4 receives the light passing through the light splitting module 2, and the light is reflected to different angles by the scanning module 4; in an embodiment, the scanning module 4 can be a one-dimensional scanning galvanometer group, the scanning angle can be set to ±10°, and then enter the magnification module 5;

[0066] In order to reduce the overall installation length of the rotating parabolic fundus imaging system and more centralized arrangement, the converging light is folded by 90° with the optical axis direction of the magnification module 5 after passing through the one-dimensional scanning galvanometer group.

[0067] 1.4, the magnification module 5 is used for receiving the light passing through the scanning module 4 and transmitting the light to the parabolic reflection module 6 after field of view magnification; in an embodiment, the scanning field of view expansion is set to n times, and when the scanning angle is set to ±10°, the scanning light beam is scanned and magnified to ±n*10° by the magnification module 5;

[0068] As shown in FIG. 1, the rotating shaft A is set, and the optical axis of the magnification module 5 and the eye axis of the eyeball are coaxial with the rotating shaft A. Figure 1

[0069] 1.5, the parabolic reflection module 6 includes at least one group of parabolic mirrors, and the at least one group of parabolic mirrors are sequentially and spacedly arranged along the optical axis direction of the magnification module 5;

[0070] In the embodiment, the at least one group of parabolic mirrors includes one group or more, when the at least one group of parabolic mirrors is one group, the one group of parabolic mirrors is arranged behind the magnification module 5 along the first light path direction; when the at least one group of parabolic mirrors is two groups or more, the two groups or more of parabolic mirrors are sequentially and spacedly arranged along the optical axis direction of the magnification module 5;

[0071] Each group of parabolic mirrors includes a pair of parabolic concave mirrors, the pair of parabolic concave mirrors are arranged on both sides of the optical axis of the magnification module 5, and the concave surfaces of the pair of parabolic concave mirrors are oppositely arranged, the focal points of each parabolic concave mirror are on the optical axis of the magnification module 5, and the two focal points of the pair of parabolic concave mirrors are arranged on both sides corresponding to the pair of parabolic concave mirrors;

[0072] ​At least one group of parabolic mirrors is arranged to rotate 360° around the optical axis of the magnification module 5 as the rotation axis.

[0073] In one embodiment, the parabolic reflection module 6 includes one group of parabolic mirrors, the focal point of one parabolic mirror of the group constitutes the first conjugate point 501, and the conjugate plane where the first conjugate point 501 is located is the real entrance pupil of the magnification module 5; the focal point of another parabolic mirror of the group constitutes the second conjugate point, and the conjugate plane where the second conjugate point is located is the pupil of the human eye 701, so as to realize the conjugation between the pupil of the human eye 701 and the real entrance pupil of the magnification module 5.

[0074] In another embodiment, the parabolic reflection module 6 includes two or more groups of parabolic mirrors, the two or more groups of parabolic mirrors are arranged in sequence along the direction in which the rotation axis A extends, the focal points of any two adjacent groups of parabolic mirrors located on the adjacent sides coincide, and the conjugate planes where the focal points located at the two ends of the two or more groups of parabolic mirrors (also the focal points located at the two ends of the parabolic reflection module 6 along the direction of the optical axis of the magnification module 5, which are defined as the first conjugate point 501 and the second conjugate point respectively) are the real entrance pupil of the magnification module 5 and the pupil of the human eye 701 respectively; that is, the focal point of one parabolic mirror (close to one end of the magnification module 5) of the parabolic reflection module 6 constitutes the first conjugate point 501, and the conjugate plane where the first conjugate point 501 is located is the real entrance pupil of the magnification module 5; the focal point of another parabolic mirror (far from one end of the magnification module 5) of the parabolic reflection module 6 constitutes the second conjugate point, and the conjugate plane where the second conjugate point is located is the pupil of the human eye 701, so as to realize the conjugation between the pupil of the human eye 701 and the real entrance pupil of the magnification module 5.

[0075] It should be noted that for each group of parabolic mirrors, the light transmission direction between the two parabolic mirrors is parallel to the main axis of the parabolic mirror, and all the light rays parallel to the main axis are reflected by the parabolic mirror after being incident on the parabolic mirror, and the reflected rays will converge on the main axis in front of the parabolic mirror, and the converging point is called the focal point of the parabolic mirror.

[0076] In this embodiment, referring to Figure 2 , the parabolic reflection module 6 includes two groups of parabolic mirrors, and different colors of transmission light rays represent the transmission direction of the light rays, and the parabolic reflection module 6 includes a fourth parabolic mirror, a third parabolic mirror, a second parabolic mirror and a first parabolic mirror along the direction of the optical path away from the magnification module 5; the focal point of the fourth parabolic mirror forms the first conjugate point 501; the focal points of the third parabolic mirror and the second parabolic mirror overlap to form an overlapping focal point 601, and the overlapping focal point 601 is on the rotation axis A; the focal point of the first parabolic mirror forms the second conjugate point, that is, the pupil of the human eye 701; this arrangement makes the pupil of the human eye 701 and the first conjugate point 501 (the real entrance pupil of the magnification module 5) form a conjugate relationship, which is convenient for the magnification module 5 to correct the aberration of the imaging system.

[0077] 1.6, the human eye 7 receives the light transmitted by the parabolic reflecting module 6, and the human eye 7 is illuminated.

[0078] II. Collecting along the second light path direction (return route)

[0079] The second light path direction (return route) includes: the light reflected by the human eye 7 returns along the incident route in turn through the parabolic reflecting module 6, the amplifying module 5, the scanning module 4 to the light splitting module 2, and reaches the light detection module for imaging processing after being reflected by the light splitting module 2.

[0080] In one embodiment, the light detection module includes a detector 8 and a host computer 9. The detector 8 can be a single-pixel detector 8, which is used to convert the received light signal into an electrical signal and transmit it to the host computer 9. The host computer 99 performs algorithm processing and reconstructs the fundus picture. Figure 1 Only one single-pixel detector 8 is shown in the figure, but in actual use, the reflected light is split by the light splitting module 2, and different wavelengths of light reach different single-pixel detectors 8 for imaging.

[0081] III. Imaging

[0082] Referring to Figure 3 The above (I. Illumination along the first light path direction (incident route)), (II. Collecting along the second light path direction (return route)) are the results of one cycle of vibration of the galvanometer of the scanning module 4, and only the image information of a line field of view from the center to the edge of the fundus is obtained;

[0083] Referring to Figure 4 When the parabolic reflector and the scanning module 4 make a circular motion with the rotation axis A as the center axis synchronously, and the human eye 7 and the amplifying module 5 remain relatively static, the line field of view on the fundus will also rotate around the rotation axis A with the rotation axis A as the center. After the parabolic reflecting module 6 rotates 360°, the line field of view on the fundus also rotates 360° around the center, covering the entire fundus. That is, when the laser is scanned by the scanning module 4 once, a line scanning beam is formed on the fundus. When the parabolic reflecting module 6 and the scanning module rotate around the optical axis synchronously, the line scanning beam also rotates around the rotation axis A. When the line scanning beam rotates 360°, it completes a complete scanning and imaging on the fundus.

[0084] Embodiment 2

[0085] Embodiment 2 of the present application discloses a rotating parabolic fundus imaging system, referring to Figure 1The embodiment is different from the embodiment 1 in that, in order to converge light rays to improve the transmission effect of the light rays, the rotating parabolic fundus imaging system further comprises an imaging module, and the imaging lens group 3 is arranged between the light splitting module 2 and the scanning module 4, used for receiving the transmitted light passing through the light splitting module 2 at a certain ratio, playing a role of converging the light rays, and transmitting the converged light rays to the scanning module 4.

[0086] In one embodiment, the imaging module comprises at least three spherical lenses arranged in sequence away from the light splitting module 2; in one specific embodiment, the imaging module comprises a plano-convex lens, a double-concave lens and a double-convex lens arranged in sequence away from the light splitting module 2.

[0087] Embodiment 3

[0088] The embodiment 3 of the application discloses a rotating parabolic fundus imaging system, which refers to Figure 5 The embodiment is different from the embodiment 2 in that the magnifying module 5 comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence away from the scanning module 4.

[0089] The first lens is a cemented lens obtained by cementing a pair of lenses, the first surface in the first light path direction is a concave surface with a curvature radius of 220-280 mm, the second surface is a concave surface relative to the first surface with a curvature radius of 15-30 mm, and the third surface is a convex surface with a curvature radius of 80-120 mm; the center thickness between the first surface and the second surface is 7-8 mm, and the center thickness between the second surface and the third surface is 4-5 mm.

[0090] The first surface of the second lens in the first light path direction is a convex surface with a curvature radius of -130--190 mm, and the second surface is a convex surface with a curvature radius of 40-70 mm; the center thickness of the second lens is 7-9 mm.

[0091] The first surface of the third lens in the first light path direction is a convex surface with a curvature radius of -15--35 mm, and the second surface is a concave surface with a curvature radius of -200--250 mm; the center thickness of the third lens is 7-8 mm.

[0092] The first surface of the fourth lens in the first light path direction is a convex surface with a curvature radius of -10--20 mm, and the second surface is a concave surface with a curvature radius of -20--40 mm; the center thickness of the fourth lens is 8-10 mm.

[0093] The first surface of the fifth lens in the first light path direction is a convex surface with a curvature radius of -5--15 mm, and the second surface is a convex surface with a curvature radius of 5-15 mm; the center thickness of the fifth lens is 7-8 mm.

[0094] The first lens, the second lens, the third lens, the fourth lens and the fifth lens are adjusted in the actual preparation process according to the actual situation within the above setting range.

[0095] The gap between the second lens and the first lens is 35-45mm; the gap between the second lens and the third lens is 60-70mm; the gap between the third lens and the fourth lens is 3-8mm; the gap between the fourth lens and the fifth lens is 3-8mm; and the distance between adjacent lenses is adjusted in the actual preparation process according to the actual situation.

[0096] Embodiment 4

[0097] Embodiment 4 of the present application discloses a rotating parabolic fundus imaging system, referring to Figure 5 The difference between the present embodiment and embodiment 3 is that the magnification module 5 further comprises a refractive compensation device 502 for compensating for different refractive eyes 7.

[0098] The refractive compensation device 502 is movably arranged between the second lens and the third lens, and the movement of the refractive compensation device 502 can be controlled by a mechanical structure to move its position, to compensate for the aberration of the refractive eye 7, so that when adjusting the refractive eye 7, only the refractive compensation device 502 is displaced along the optical axis, and the total length of the magnification module 5 remains unchanged.

[0099] The refractive compensation device 502 comprises a sixth lens and a seventh lens with a gap of 3-8mm, and the distance between the sixth lens and the seventh lens is determined according to the actual situation in the actual preparation process.

[0100] The first surface of the sixth lens along the first light path direction is a convex surface with a curvature radius of -40 to -70mm, and the second surface is a convex surface with a curvature radius of 800-1200mm, and the center thickness of the sixth lens is 4-5mm.

[0101] The first surface of the seventh lens along the first light path direction is a concave surface with a curvature radius of 15-35mm, and the second surface is a convex surface with a curvature radius of 70-100mm, and the center thickness of the seventh lens is 4-5mm.

[0102] The sixth lens and the seventh lens are adjusted in the actual preparation process according to the actual situation within the above setting range.

[0103] The movement distance of the refractive compensation device 502 relative to the third lens is 15-55mm, i.e. the distance between the refractive compensation device 502 and the third lens can be adjusted between 15-55mm.

[0104] Experiment

[0105] Using the rotating parabolic fundus imaging system of Example 3, based on the magnification module, full field of view imaging was performed at light source emission wavelengths of 488 nm, 520 nm, 635 nm, and 785 nm, respectively, and the full field of view point graphs are shown in Figures 6-9 , Figure 6 , Figure 7 , Figure 8 , Figure 9 ,

[0106] As shown in Figures 6-9 , images of 9 fields of view were obtained at each wavelength (1-9 fields of view correspond to the object plane extending from -0.00 mm to -11.99 mm, respectively), and the GEO radius for each field of view is shown in Table 1:

[0107] Table 1 GEO radius

[0108] 488 nm 520 nm 635 nm 785 nm Field of view 1 8.909 μm 10.122 μm 9.145 μm 3.847 μm Field of view 2 2.820 μm 3.090 μm 2.471 μm 6.120 μm Field of view 3 7.170 μm 6.009 μm 6.484 μm 11.037 μm Field of view 4 9.473 μm 8.152 μm 8.476 μm 13.152 μm Field of view 5 9.572 μm 11.080 μm 11.297 μm 10.848 μm Field of view 6 9.544 μm 11.073 μm 11.826 μm 11.738 μm Field of view 7 7.097 μm 6.398 μm 6.937 μm 9.055 μm Field of view 8 10.496 μm 6.601 μm 5.390 μm 7.332 μm Field of view 9 8.360 μm 7.936 μm 10.262 μm 14.633 μm

[0109] As shown in Table 1 in combination with Figures 6-9 , the combination of the rotatable parabolic concave mirror, the scanning module, and the magnification module achieves ultra-wide angle fundus imaging at a long working distance, and the system has high resolution and is free of pupil dilation. There is no field of view missing in the full field of view, and the optical resolution of the full field of view is 15 um.

[0110] The embodiments of the present specific embodiment are preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. The same parts are indicated by the same reference numerals. Therefore, equivalent changes made in accordance with the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A rotating parabolic fundus imaging system, characterized by, The application relates to a light detection module and a light source module (1), a light splitting module (2), a scanning module (4), an amplification module (5) and a parabolic reflection module (6) arranged along a first light path direction in sequence, wherein the light detection module is arranged along a second light path direction in sequence with the light splitting module (2) as a starting point and is used for receiving reflected light generated by a human eye (7) and imaging; The parabolic reflection module (6) comprises at least one group of parabolic mirrors, and the at least one group of parabolic mirrors is arranged along the optical axis direction of the amplification module (5) in sequence and at intervals; Each group of parabolic mirrors comprises a pair of parabolic concave mirrors, the pair of parabolic concave mirrors are arranged on both sides of the optical axis of the amplification module (5) and oppositely arranged, the focal points of each parabolic concave mirror fall on the optical axis of the amplification module (5), and the focal points of any two adjacent groups of parabolic mirrors coincide, and the conjugate planes where the focal points at both ends of the at least one group of parabolic mirrors are located are a real entrance pupil of the amplification module (5) and a human eye pupil (701) respectively; The at least one group of parabolic mirrors and the scanning module (4) are rotatably arranged at 360 degrees with the optical axis of the amplification module (5) as a rotating shaft.

2. The rotating prolate spheroid fundus imaging system of claim 1, wherein, The light source module (1) is one of a single-wavelength light source and a multi-wavelength light source.

3. The rotating prolate spheroid fundus imaging system of claim 1, wherein, The parabolic reflection module (6) comprises 1-2 groups of parabolic mirrors.

4. The rotating prolate spheroid fundus imaging system of claim 1, wherein, The scanning module (4) realizes 90-degree folding of light.

5. The rotating prolate spheroid fundus imaging system of claim 3, wherein, The amplification module (5) comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged along a first light path direction in sequence; The first lens is a cemented lens, the first surface along the first light path direction is a concave surface, the curvature radius is set to 220-280 mm, the second surface is a concave surface relative to the first surface, the curvature radius is set to 15-30 mm, the third surface is a convex surface, the curvature radius is set to 80-120 mm, the center thickness between the first surface and the second surface is 7-8 mm, and the center thickness between the second surface and the third surface is 4-5 mm; The second lens is a convex surface along the first light path direction, the curvature radius is set to -130 to -190 mm, the second surface is a convex surface, the curvature radius is set to 40-70 mm, and the center thickness is 7-9 mm; The third lens is a convex surface along the first light path direction, the curvature radius is set to -15 to -35 mm, the second surface is a concave surface, the curvature radius is set to -200 to -250 mm, and the center thickness is 7-8 mm; The fourth lens is a convex surface along the first light path direction, the curvature radius is set to -10 to -20 mm, the second surface is a concave surface, the curvature radius is set to -20 to -40 mm, and the center thickness is 8-10 mm; The fifth lens is a convex surface along the first light path direction, the curvature radius is set to -5 to -15 mm, the second surface is a convex surface, the curvature radius is set to 5-15 mm, and the center thickness is 7-8 mm.

6. The rotating prolate spheroid fundus imaging system of claim 5, wherein, The gap between the second lens and the first lens is 35-45 mm; the gap between the second lens and the third lens is 60-70 mm; the gap between the third lens and the fourth lens is 3-8 mm; and the gap between the fourth lens and the fifth lens is 3-8 mm.

7. The rotating prolate spheroid fundus imaging system of claim 5, wherein, The magnification module (5) further comprises a refractive compensation device (502) movably arranged between the second lens and the third lens.

8. The rotating prolate spheroid fundus imaging system of claim 7, wherein, The refractive compensation device (502) comprises a sixth lens and a seventh lens arranged in sequence along the first light path direction with a gap of 3-8 mm. The first surface of the sixth lens along the first light path direction is a convex surface with a curvature radius of -40 to -70 mm, and the second surface is a convex surface with a curvature radius of 800-1200 mm and a center thickness of 4-5 mm. The first surface of the seventh lens along the first light path direction is a concave surface with a curvature radius of 15-35 mm, and the second surface is a convex surface with a curvature radius of 70-100 mm and a center thickness of 4-5 mm. The movement distance range of the refractive compensation device (502) relative to the third lens is 15-55 mm.

9. The rotating prolate spheroid fundus imaging system of claim 1, wherein, Further comprising an imaging lens group (3) arranged between the light splitting module (2) and the scanning module (4) for converging the transmitted light passing through the light splitting module (2) and converging to the scanning module (4).

10. A method of rotating parabolic fundus imaging, characterized by, The rotating parabolic fundus imaging system of any one of claims 1-9 is used, and the at least one set of parabolic mirrors and the scanning module (4) are rotated 360° around the optical axis of the magnification module (5) for one round of fundus imaging.

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