Fundus imaging illumination device and optical apparatus

Abstract

The invention provides a fundus imaging illuminating device and optical equipment. The fundus imaging illuminating device comprises an illuminating light source and a reflecting mirror which are sequentially arranged from far to near according to the distance from human eyes; the illumination light source is used for emitting illumination light; the illumination light is focused in front of human eyes or between a cornea and a crystalline lens after being reflected by the reflector; illuminating light rays are diffused to the retina to form uniform illuminating light spots. In the mode, a non-contact fundus imaging illumination arrangement scheme can be provided, an ocular surface coupling agent does not need to be used, the precision of OCT and OCTA is guaranteed, and fundus imaging, OCT and OCTA can be integrated into the same equipment. The focusing position of the illuminating light source passing through the transmitting mirror is adjustable, and crosstalk of many illuminating light rays on a light path can be avoided. And equipment miniaturization can be better realized by adjusting the positions of the light source and the reflecting mirror.

Description

Technical Field

[0001] This invention relates to the field of optical technology, and in particular to a fundus imaging illumination device and optical equipment. Background Technology

[0002] Retinopathy of prematurity (ROP) is the leading cause of blindness in children, causing 4 to 6 million deaths annually. In China, with over 10 million newborns each year and a preterm birth rate exceeding 10%, 65.8% of infants weighing less than 1251g exhibit various manifestations of ROP. Analysis by gestational age shows a 30% incidence of ROP in infants with a gestational age greater than 31 weeks and an 83% incidence in infants with a gestational age less than 28 weeks. ROP is treatable; over 90% of children with ROP can retain their vision through treatment, provided that early detection and screening are actively pursued.

[0003] Retinopathy of prematurity (ROP) in infants and young children usually begins in the peripheral retinal area. However, because affected children have difficulty actively cooperating with eye movements, routine examinations cannot fully observe the retinal margins. To address this issue, ultra-wide-angle fundus imaging technology is used clinically. These devices obtain the largest possible field of retinal imaging by directly contacting the surface of the eyeball and being as close as possible to the pupil.

[0004] Currently, commercially available fundus cameras use lenses that directly contact the surface of the eyeball, employing a coupling agent and a ring-shaped off-axis illumination method. Existing fundus cameras only perform fundus imaging and all use off-axis ring illumination to illuminate the fundus. To obtain a larger field of view, the lens needs to directly contact the eye surface, requiring a coupling agent to be applied to prevent injury. When using contact-type fundus imaging illumination equipment, the eye surface must be covered with a coupling agent. Using a coupling agent means the equipment has limited functionality, and the accuracy of integrating OCT (Optical Coherence Tomography) and OCTA (Optical Coherence Tomography Angiography) is difficult to guarantee. The location of the light source divergence point in the ring illumination arrangement is particularly important, as it easily generates a lot of stray light that interferes with the fundus imaging optical path. A focal point between the cornea and lens is currently impossible to achieve with ring-shaped light arrangements; while stray light can achieve the effect of coaxial illumination, the volume is much smaller. While an existing fundus imaging device can also perform OCT, its contact-based operation and the use of coupling gel prevent it from having OCTA functionality. Furthermore, in practical use, its OCT field of view is very small. Summary of the Invention

[0005] In view of this, the purpose of this invention is to provide a fundus imaging illumination device and optical equipment, offering a non-contact fundus imaging illumination arrangement scheme that eliminates the need for ocular surface coupling agents, ensures the accuracy of OCT and OCTA, and integrates fundus imaging with OCT and OCTA into the same device. The focusing position of the illumination source via the reflecting mirror is adjustable, avoiding much crosstalk of illumination rays in the optical path. Adjusting the positions of the light source and the reflecting mirror also allows for better miniaturization of the device.

[0006] In a first aspect, embodiments of the present invention provide a fundus imaging illumination device, comprising: an illumination source and a reflector arranged sequentially from far to near the human eye; the illumination source emits illumination light; the illumination light is reflected by the reflector and focused in front of the human eye or at a position between the cornea and the lens; the illumination light is diffused onto the retina to form a uniform illumination spot.

[0007] In an optional embodiment of this application, the above-mentioned fundus imaging illumination device is arranged with multiple sets of illumination sources and reflectors in a rotationally symmetrical manner.

[0008] In an optional embodiment of this application, the above-mentioned uniform illumination of the fundus is achieved by using multiple sets of illumination sources and reflectors, and the arrangement of the multiple sets of illumination sources and reflectors is symmetrical with respect to the human eye.

[0009] In an optional embodiment of this application, the above-mentioned lighting source includes: LED beads, wherein the divergence angle of the LED beads is 55-80°.

[0010] In an optional embodiment of this application, the above-mentioned lighting source includes: an optical fiber bundle with an outer diameter of 10 mm.

[0011] In optional embodiments of this application, the mirror surface of the above-mentioned reflector includes: a spherical surface, an aspherical surface, or a freeform surface.

[0012] In an optional embodiment of this application, the focal position of the illumination light after reflection by the reflector is determined based on the position of the illumination source, the tilt angle of the illumination source, the position of the reflector, and the tilt angle of the reflector.

[0013] In an optional embodiment of this application, the wavelength of the illumination light is 810-860nm.

[0014] Secondly, embodiments of the present invention also provide an optical device, which includes the above-described fundus imaging illumination device.

[0015] In an optional embodiment of this application, the optical device is used to receive light rays returning from the human eye after passing through the illumination spot formed by the fundus imaging illumination device; the light rays form a fundus image based on the fundus imaging optical path of the optical device.

[0016] The embodiments of the present invention bring the following beneficial effects: This invention provides a fundus imaging illumination device and optical equipment. The illumination source and reflector are arranged sequentially from farthest to near the eye. The illumination source emits illumination light; the illumination light is reflected by the reflector and focused at a position in front of the eye or between the cornea and lens; the illumination light diverges onto the retina to form a uniform illumination spot. This method provides a non-contact fundus imaging illumination arrangement, eliminating the need for ocular surface coupling agents, ensuring the accuracy of OCT and OCTA, and allowing fundus imaging, OCT, and OCTA to be integrated into the same device. The focusing position of the illumination source after the reflector is adjustable, avoiding much crosstalk in the optical path. Adjusting the positions of the light source and reflector also facilitates device miniaturization.

[0017] Other features and advantages of this disclosure will be set forth in the following description, or some features and advantages may be inferred from the description or determined without doubt, or may be learned by practicing the techniques described above.

[0018] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

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

[0020] Figure 1 This is a schematic diagram of a fundus imaging illumination device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of fundus illumination for a fundus imaging illumination device with 16 sets of light sources and reflectors provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of an optical device provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of a fundus imaging illumination device according to embodiment 2 of the present invention; Figure 5 This is a schematic diagram of a fundus imaging illumination device according to embodiment 3 of the present invention; Figure 6 A schematic diagram of X-axis irradiance values ​​for fundus illumination provided in an embodiment of the present invention; Figure 7This is a schematic diagram of the Y-axis irradiance value of fundus illumination provided in an embodiment of the present invention.

[0021] Icons: 1-Light source; 2-Reflector; 3-Focus point where light rays converge. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions 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, 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.

[0023] Currently, commercially available fundus cameras use lenses that directly contact the surface of the eyeball, employing a coupling agent and a ring-shaped off-axis illumination method. Existing fundus cameras only perform fundus imaging, all using off-axis ring illumination to illuminate the fundus. To obtain a large field of view, the lens needs to directly contact the eye surface, requiring a coupling agent to be applied to prevent injury. When using contact-type fundus imaging illumination devices, the eye surface must be covered with a coupling agent. Using a coupling agent means the device's functionality is limited, and the accuracy of integrated OCT and OCTA is difficult to guarantee. The location of the light source divergence point in the ring illumination arrangement is particularly important, as it easily generates a lot of stray light that interferes with the fundus imaging optical path. A focal point between the cornea and lens is currently impossible to achieve with the ring-shaped light arrangement; while stray light can achieve the effect of coaxial illumination, the volume is much smaller. While an existing fundus imaging device can also perform OCT, its contact-type operation and the use of a coupling agent prevent it from having OCTA functionality. Furthermore, in practical use, its OCT field of view is very small.

[0024] Based on this, the fundus imaging illumination device and optical equipment provided in this embodiment of the invention offer a non-contact fundus imaging illumination arrangement scheme. It eliminates the need for ocular surface coupling agents, ensuring the accuracy of OCT and OCTA. Fundus imaging, OCT, and OCTA can be integrated into the same device. The focusing position of the illumination source via the reflecting mirror is adjustable, avoiding crosstalk of many illumination rays in the optical path. Adjusting the positions of the light source and the reflecting mirror also facilitates device miniaturization.

[0025] To facilitate understanding of this embodiment, a fundus imaging illumination device disclosed in this embodiment of the invention will first be described in detail.

[0026] Example 1: This invention provides a fundus imaging illumination device, see [link to relevant documentation]. Figure 1The diagram shows a fundus imaging illumination device, which includes: an illumination source 1 and a reflector 2 arranged in order of distance from the human eye from far to near; The illumination source emits illumination light; after being reflected by a mirror, the illumination light is focused in front of the eye or between the cornea and the lens; the illumination light is diffused onto the retina to form a uniform illumination spot.

[0027] like Figure 1 As shown, the focal point 3 where the illumination light converges is located in front of the human eye G100 or between the cornea and the lens.

[0028] The fundus imaging illumination arrangement device provided in this embodiment can use an illumination source and a reflector in a fixed combination, but the positions of both can be adjusted. The reflector can also be optimized into a specific curved shape to make the focal point of the illumination light adjustable. The focal point is located between the cornea and the lens, which is something that current ring light arrangement schemes cannot achieve. Its stray light achieves the effect of coaxial illumination, and its volume is much smaller than that of coaxial illumination.

[0029] In some embodiments, the fundus imaging illumination device of this embodiment can satisfy the following condition: (1) 6mm <EPD<8mm; Here, EPD represents the entrance pupil diameter of the human eye. When the fundus imaging illumination device is in use, the pupil of the human eye is equivalent to the aperture stop of the optical system. If the above conditions are met, it can perfectly match the pupil diameter of infants aged 0-3 years after pupil dilation, and prevent the light from being blocked when the illumination light enters the eye.

[0030] (2) 2 <TTL<4; The length of the fundus imaging illumination device is TTL, which is the distance from the side of the reflector to the frame of the human eye.

[0031] This invention provides a fundus imaging illumination device, in which an illumination source and a reflector are arranged sequentially from farthest to near the eye; the illumination source emits illumination light; the illumination light is reflected by the reflector and focused at a position in front of the eye or between the cornea and lens; the illumination light is diffused onto the retina to form a uniform illumination spot. This method provides a non-contact fundus imaging illumination arrangement, eliminating the need for ocular surface coupling agents, ensuring the accuracy of OCT and OCTA, and allowing fundus imaging, OCT, and OCTA to be integrated into the same device. The focusing position of the illumination source after the reflector is adjustable, avoiding much crosstalk in the optical path. Adjusting the positions of the light source and reflector also facilitates device miniaturization.

[0032] Example 2: This embodiment provides another fundus imaging illumination device, which is implemented based on the above embodiment. The specific structure of the fundus imaging illumination device is described in detail.

[0033] In some embodiments, the above-described fundus imaging illumination device is arranged with multiple sets of illumination sources and reflectors in a rotationally symmetrical manner.

[0034] The number of groups of the aforementioned lighting sources and reflectors is 8-16.

[0035] To achieve a uniform illumination spot in this embodiment, 8-16 sets of light sources and reflectors need to be arranged rotationally symmetrically. (See also...) Figure 2 The diagram shows a fundus illumination schematic of a fundus imaging illumination device with 16 sets of light sources and reflectors. Figure 2 The image shows the illumination spot achieved by the optimal illumination arrangement of the fundus imaging illumination device.

[0036] In some embodiments, uniform illumination of the fundus is achieved by using multiple sets of illumination sources and reflectors, and the arrangement of the multiple sets of illumination sources and reflectors is symmetrical with respect to the human eye.

[0037] In this embodiment, the multiple sets of lighting sources and reflectors can be arranged symmetrically relative to the human eye, thereby achieving uniform illumination of the fundus.

[0038] The working mode of the fundus imaging illumination device in this embodiment is non-contact, which will not cause damage to the human cornea and does not require the use of coupling agent, which helps to ensure the accuracy of fundus coherent blood flow imaging technology.

[0039] In some embodiments, the above-mentioned lighting source includes: LED beads, wherein the divergence angle of the LED beads is 55-80°.

[0040] In some embodiments, the above-mentioned lighting source includes: an optical fiber bundle with an outer diameter of 10 mm.

[0041] In this embodiment, the lighting source can be an LED chip or a large NA (Numerical Aperture) optical fiber. If an LED chip is used, its divergence angle can be approximately 55-80°; if a large NA optical fiber is used, the outer diameter of the fiber bundle can be approximately 10mm.

[0042] In some embodiments, the mirror surface of the above-mentioned reflector includes a spherical surface, an aspherical surface, or a freeform surface.

[0043] In this embodiment, the reflector can be an optimized surface such as a spherical, aspherical, or freeform surface, thereby better focusing the illumination light.

[0044] In some embodiments, the focal position of the illumination light after reflection by the reflector is determined based on the position of the illumination source, the tilt angle of the illumination source, the position of the reflector, and the tilt angle of the reflector.

[0045] In this embodiment, the position and tilt angle of the lighting source and the reflector are adjustable. In this embodiment, the focal position of the lighting light after reflection by the reflector can be adjusted by adjusting the position and tilt angle of the lighting source and the reflector.

[0046] In this embodiment, the illumination light is focused after passing through the reflector. The focal point is located either in front of the person's eyes or between the cornea and the lens. Appropriately adjusting the focal point of the illumination light after passing through the reflector can help avoid interference of the illumination light with the fundus imaging optical path and can also adjust the working distance to facilitate the user's operation.

[0047] In some embodiments, the wavelength of the illumination light is 810-860nm.

[0048] In this embodiment, the illumination light wavelength can be selected as 810-860nm, which facilitates the setting of the light source for the main optical path OCT and OCT.

[0049] Example 3: This embodiment provides an optical device, implemented based on the above embodiments. See [link to previous embodiment]. Figure 3 The diagram shows the structure of an optical device, which includes the fundus imaging illumination device provided in the aforementioned embodiments.

[0050] In some embodiments, the optical device is used to receive light rays returning from the human eye after passing through an illumination spot formed by a fundus imaging illumination device; the light rays form a fundus image based on the fundus imaging optical path of the optical device.

[0051] The optical device in this embodiment can be an OCT or OCT-TA device, and its light transmission can be as follows: the illumination light emitted by the illumination source is first focused by a reflector and then gradually diffused into the human eye, forming a uniform illuminated spot on the retina. The human eye has a high reflectivity to infrared light, so 810-860nm is used as the illumination band. Some of the light is reflected back by the human eye, and the reflected light passes through the fundus imaging optical path to finally form a fundus image.

[0052] In this embodiment, the OCT or OCTA device can use a swept-frequency light source with a wavelength of 1060-1150nm and an illumination wavelength of 810-860nm. The wavelength of the fundus imaging illumination device does not conflict with the wavelength of the OCT or OCTA device.

[0053] Example 4: This embodiment provides another fundus imaging illumination device, implemented based on the above embodiments, specifically offering three concrete implementation methods for the fundus imaging illumination device. Given the requirement for precise focusing of the illumination light, the positional relationships of the various components in each embodiment of this invention are unique. Through meticulous optimization of the overall system architecture, the position of the light source, and the curved surface of the reflector, the goal of achieving uniformity and miniaturization of the fundus imaging illumination spot in infants and young children is synergistically achieved.

[0054] Implementation Approach 1: The lighting arrangement scheme is implemented in non-sequential mode of Zemax (an optical design and simulation software suite), with parameters shown in Table 1.

[0055] Table 1

[0056] Implementation Approach 2: Lighting layout scheme in Zemax non-sequential mode, parameters are shown in Table 2.

[0057] Table 2

[0058] Implementation Approach 3: Lighting layout scheme in Zemax non-sequential mode, parameters are shown in Table 3.

[0059] Table 3

[0060] In addition, the light source angles for implementation methods 1-3 are shown in Table 4.

[0061] Table 4

[0062] Among them, the optical path of implementation method 1 can be as follows: Figure 1 As shown, the optical paths of implementation path 2 and implementation path 3 can be found in the following references. Figure 4 A schematic diagram of a fundus imaging illumination device according to one embodiment 2 is shown. Figure 5 A schematic diagram of a fundus imaging illumination device according to one embodiment 3 is shown.

[0063] like Figure 1 , 4 As shown in Figure 5, the illumination light, after passing through the focal point converged by the reflector, gradually enters the cornea of ​​the human eye. The change in the focal point position is caused by the position of the light source, the curvature of the reflector, and its distance from the eye. The closer the focal point is to the eye, the less crosstalk in the imaging optical path of the fundus.

[0064] See also Figure 6 A schematic diagram of X-axis irradiance values ​​for fundus illumination is shown. Figure 7 This diagram illustrates the Y-axis irradiance values ​​for fundus illumination. Figure 6 and Figure 7 As shown, the uniformity of the illumination spot is good.

[0065] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system and / or device described above can be referred to the corresponding process in the foregoing embodiments, and will not be repeated here.

[0066] Furthermore, in the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0067] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0068] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0069] Finally, it should be noted that the above embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A fundus imaging illumination device, characterized in that, The fundus imaging illumination device includes: an illumination source and a reflector arranged in order of distance from the human eye from farthest to nearest; The lighting source emits light to illuminate the light source; The illumination light, after being reflected by the mirror, is focused in front of the person's eyes or at a position between the cornea and the lens; The illumination light is diffused onto the retina to form a uniform illumination spot.

2. The fundus imaging illumination device according to claim 1, characterized in that, The fundus imaging illumination device is arranged with multiple sets of illumination sources and reflectors in a rotationally symmetrical manner.

3. The fundus imaging illumination device according to claim 2, characterized in that, Uniform illumination of the fundus is achieved by using multiple sets of illumination sources and reflectors, and the arrangement of the multiple sets of illumination sources and reflectors is symmetrical with respect to the human eye.

4. The fundus imaging illumination device according to claim 1, characterized in that, The lighting source includes LED beads, wherein the divergence angle of the LED beads is 55-80°.

5. The fundus imaging illumination device according to claim 1, characterized in that, The lighting source includes an optical fiber bundle with an outer diameter of 10 mm.

6. The fundus imaging illumination device according to claim 1, characterized in that, The mirror surface includes: a spherical surface, an aspherical surface, or a freeform surface.

7. The fundus imaging illumination device according to claim 1, characterized in that, The focal position of the illumination light after reflection by the reflector is determined based on the position of the illumination source, the tilt angle of the illumination source, the position of the reflector, and the tilt angle of the reflector.

8. The fundus imaging illumination device according to claim 1, characterized in that, The wavelength of the illumination light is 810-860nm.

9. An optical device, characterized in that, The optical device includes: the fundus imaging illumination device according to any one of claims 1-8.

10. The optical device according to claim 9, characterized in that, The optical device is used to receive the light reflected back from the human eye by the illumination spot formed by the fundus imaging illumination device; The light rays form a fundus image based on the fundus imaging optical path of the optical device.

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