Device and method for measuring fundus view field range of non-contact wide-angle lens

Abstract

The invention provides a non-contact wide-angle lens fundus view field range measuring device and method, and relates to the technical field of wide-angle lens measurement, the device comprises a shell, the top end of the shell is provided with a mounting hole, the inner circumferential wall or the outer circumferential wall of the shell is provided with a plurality of scale marks, and the scale marks extend in the circumferential direction of the shell and are arranged at intervals in the axial direction; and the diaphragm is connected with the shell and is arranged at the mounting hole, and the inner diameter d of the diaphragm is more than or equal to 4mm and less than or equal to 8mm. The non-contact wide-angle lens fundus field-of-view range measuring device can measure the field-of-view range of the wide-angle lens under the simulated real clinic, so that a doctor can judge the performance of the wide-angle lens conveniently, the doctor or a hospital can purchase the wide-angle lens conveniently, and the measuring accuracy is improved based on the fact that diaphragms with different inner diameters are simulated in advance. A doctor can quickly move the wide-angle lens to the optimal working distance during a clinical operation, so that the operation efficiency is improved.

Description

A non-contact wide-angle lens fundus field of view measurement device and method Technical Field

[0001] This invention relates to the field of wide-angle lens measurement technology, and more specifically, to a non-contact wide-angle lens fundus field of view measurement device and method. Background Technology

[0002] Currently, non-contact wide-angle fundus observation lenses are widely used in fundus microsurgery. A non-contact wide-angle fundus observation lens consists of two optical components: a focusing optics unit and a wide-angle front lens. The working distance of the wide-angle front lens is the distance from the vertex of its lower surface to the vertex of the patient's outer corneal surface. The focusing optics unit of the non-contact wide-angle fundus observation lens, together with the surgical microscope objective lens, forms a variable-focus composite lens. The wide-angle front lens, located at the working distance, projects an inverted image of the patient's fundus onto the focal plane of the microscope's variable-focus composite lens. Through the optical components of the ophthalmic surgical microscope, including the zoom element, image inversion device, and eyepiece system, the observer views the fundus image and performs surgical procedures.

[0003] Non-contact fundus wide-angle observation lenses typically include two wide-angle front lenses (wide-angle lens and macular lens). The fundus observation range (the angular angle subtended by the fundus observation area on a specific cross-section with the geometric center of the eyeball as the apex) is an important technical indicator for both the wide-angle lens and the macular lens. For the wide-angle lens, the maximum fundus observation range is a crucial indicator, as it, along with transfer function and distortion characteristics, characterizes the overall performance of the wide-angle lens. The goal is to observe as large a fundus area as possible during surgery. This observation range can be further expanded by shifting or tilting the patient's eyeball relative to the non-contact fundus observation lens. Furthermore, surgical assistants can use pressure devices to press on the outer wall of the sclera, causing scleral deformation towards the inner eyeball, thus bringing the pre-observed fundus area into the field of view. This ensures that the entire fundus and retina can be observed during surgery. This is crucial for avoiding omissions and improving surgical success rates.

[0004] In the existing technology, the fundus observation range of wide-angle lenses is affected by many factors (working distance, patient pupil diameter, eye optical characteristics, etc.). However, there is no standardized and clearly defined measuring device for the fundus observation range of wide-angle lenses to measure the field of view of wide-angle lenses. The technical specifications of wide-angle lenses are only provided by relevant manufacturers, and the information is incomplete, making it difficult for doctors to directly evaluate wide-angle lenses through technical parameters. Summary of the Invention

[0005] The purpose of this invention is to provide a non-contact wide-angle lens fundus field-of-view measurement device and method to improve the above-mentioned problems. To achieve the above objective, the technical solution adopted by this invention is as follows:

[0006] In a first aspect, this application provides a non-contact wide-angle lens fundus field of view measurement device, comprising: a housing, wherein a mounting hole is provided at the top of the housing, and a plurality of scale lines are provided on the inner or outer peripheral wall of the housing, the plurality of scale lines extending circumferentially along the housing and spaced apart from each other in the axial direction; and an aperture, wherein the aperture is connected to the housing and disposed at the mounting hole, and the inner diameter of the aperture is d, satisfying: 4mm≤d≤8mm.

[0007] Secondly, this application provides a method for measuring the field of view of a non-contact wide-angle lens fundus, applicable to the non-contact wide-angle lens fundus field of view measuring device described in the first aspect, comprising: placing the non-contact wide-angle lens fundus field of view measuring device below the wide-angle lens; adjusting the distance between the wide-angle lens and the non-contact wide-angle lens fundus field of view measuring device; observing the relative position of the aperture edge and the inner edge of the wide-angle lens frame, stopping the adjustment of the distance between the wide-angle lens and the non-contact wide-angle lens fundus field of view measuring device when the aperture edge observed by the eyepiece almost overlaps with the inner edge of the wide-angle lens frame, and determining the maximum field of view position as the highest position visible inside the housing seen by the eyepiece; calculating the half-field angle and / or full-field angle based on the inner diameter of the housing, the maximum field of view position, and the inner diameter of the aperture; and calculating the fundus field of view range based on the half-field angle and the fundus field of view conversion model.

[0008] The beneficial effects of this invention are as follows:

[0009] The non-contact wide-angle lens fundus field of view measurement device according to the present invention can realize the measurement of the field of view of a wide-angle lens under simulated real clinical conditions, thereby facilitating doctors' evaluation of the performance of the wide-angle lens and making it easier for doctors or hospitals to purchase wide-angle lenses. Moreover, based on the prior simulation of apertures with different inner diameters, doctors can quickly move the wide-angle lens to the optimal working distance during clinical surgery, thereby improving surgical efficiency.

[0010] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing embodiments of the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 is a schematic diagram of the non-contact wide-angle lens fundus field of view measurement device;

[0013] Figure 2 is a schematic diagram of the combination of a wide-angle lens and a non-contact wide-angle lens fundus field of view measurement device;

[0014] Figure 3 is a schematic diagram of a non-contact wide-angle lens fundus field of view measurement method.

[0015] Marked in the diagram: 1, wide-angle lens; 10, housing; 11, scale line; 20, aperture stop. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0017] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0018] The field of view of the fundus with a wide-angle lens is affected by many factors (working distance, patient's pupil diameter, optical characteristics of the eyeball, etc.). When doctors purchase wide-angle lenses, manufacturers only provide technical specifications. However, doctors only use wide-angle lenses and do not distinguish the technical specifications. In this situation, how to choose a good and suitable wide-angle lens from a variety of different specifications has become a problem for doctors.

[0019] Example 1:

[0020] As shown in Figures 1 and 2, this embodiment provides a non-contact wide-angle lens fundus field of view measurement device, including: a housing 10 and an aperture 20. The top of the housing 10 is provided with a mounting hole. The inner or outer peripheral wall of the housing 10 is provided with a plurality of scale lines 11. The plurality of scale lines 11 extend circumferentially along the housing 10 and are spaced apart from each other in the axial direction. The aperture 20 is connected to the housing 10 and is provided at the mounting hole. The inner diameter of the aperture 20 is d, which satisfies: 4mm≤d≤8mm.

[0021] In some embodiments, the axis of the housing 10 is parallel to the height direction of the housing 10. The top of the housing 10 is provided with a mounting hole for providing a position for mounting the aperture 20. The inner or outer peripheral wall of the housing 10 is provided with a plurality of scale lines 11, which extend along the circumference of the housing 10 and are spaced apart from each other in the axial direction of the housing 10. The aperture 20 is connected to the housing 10 and is mounted at the mounting hole at the top of the housing 10. The aperture 20 has a through hole in the thickness direction, the diameter of which is the inner diameter of the aperture 20, i.e., the diameter of the through hole is d, and d satisfies: 4mm≤d≤8mm. The aperture 20 plays the role of limiting the light flux in the measuring device. Its inner diameter directly affects the range of light entering the measuring device, and thus affects the measurement of the field of view of the fundus.

[0022] It is understandable that 4mm≤d≤8mm corresponds to the clinically standard pupil diameter, and d=8mm corresponds to the pupil diameter under normal dilated conditions. The distance of each graduation line 11 relative to the aperture 20 in the height direction of the housing 10 is determined.

[0023] When using the non-contact wide-angle lens fundus field of view measurement device of this application, first place the non-contact wide-angle lens fundus field of view measurement device below the wide-angle lens 1, and then move the wide-angle lens 1 relative to the housing 10 along the height direction of the housing 10. As the wide-angle lens 1 moves toward the housing 10, the aperture 20 in the eyepiece of the surgical microscope gradually becomes larger, and the aperture 20 through hole in the surgical microscope also gradually becomes larger. When the outer periphery of the aperture 20 through hole is closest to the inner edge of the frame of the wide-angle lens 1, and the edge of the aperture 20 through hole can still be observed, stop moving the wide-angle lens 1. At this time, the position where the inner peripheral wall of the housing 10 is closest to the outer periphery of the aperture 20 through hole is the position of the maximum field of view.

[0024] Of course, after obtaining the maximum field of view of the wide-angle lens 1, the field of view that the surgical microscope can obtain will hardly increase when the wide-angle lens 1 is moved towards the housing 10. Therefore, the maximum field of view obtained by the non-contact wide-angle lens fundus field of view measurement device of this application can correspond to the optimal working distance of the wide-angle lens 1 (the working distance is the distance between the vertex of the lower surface of the wide-angle lens 1 and the aperture 20), so as to facilitate the operation of the doctor during surgery (continuing to move the wide-angle lens 1 towards the housing 10 will cause the working distance to decrease, thereby causing the surgical operation space to decrease, and the field of view will hardly increase).

[0025] Moreover, by adjusting the inner diameter of the aperture 20 in advance, the non-contact wide-angle lens fundus field of view measuring device of this application can measure the optimal working distance for different pupil diameters corresponding to the wide-angle lens 1. During clinical surgery, the doctor can quickly move the wide-angle lens 1 to the optimal working distance according to the patient's pupil diameter and the pre-measured results, thereby improving surgical efficiency.

[0026] Of course, after obtaining the maximum field of view position of the wide-angle lens 1, the fundus field of view range of the wide-angle lens 1 under the corresponding pupil diameter can be calculated based on the inner diameter of the housing 10 at the maximum field of view position, the inner diameter of the aperture 20, the distance between the maximum field of view position and the aperture 20, and the fundus field of view conversion model.

[0027] It is worth mentioning that this application is suitable for measuring and comparing the field of view of different wide-angle lenses 1. For multiple different wide-angle lenses 1, at a specific working distance (the working distance preferred by doctors, which is related to the size of the wide-angle lens, fogging characteristics, etc.) and a specific aperture (corresponding to the pupil state after the patient's pupils are dilated), the closer the maximum field of view position is to the aperture 20, the larger the field of view of the wide-angle lens 1 is. This makes it easier for doctors to compare and evaluate the performance of the wide-angle lens 1, and thus facilitates doctors' procurement.

[0028] It should be noted that the scale line 11 is set for positioning when measuring the field of view of the wide-angle lens 1, so as to facilitate determining the precise position of the maximum field of view corresponding to the wide-angle lens 1, and to facilitate measuring the distance between the maximum field of view corresponding to the wide-angle lens 1 and the aperture stop 20.

[0029] According to the non-contact wide-angle lens fundus field of view measurement device of the present invention, it can realize the measurement of the field of view of the wide-angle lens 1 under simulated real clinical conditions, thereby facilitating the doctor's evaluation of the performance of the wide-angle lens 1, and thus facilitating the procurement of the wide-angle lens 1 by the doctor or hospital. Moreover, based on the prior simulation of apertures 20 with different inner diameters, the doctor can quickly move the wide-angle lens 1 to the optimal working distance during clinical surgery, thereby improving surgical efficiency.

[0030] According to some embodiments of the present invention, some of the scale lines 11 are constructed as annular rings extending circumferentially along the housing 10. It is understood that the line connecting the center of the aperture 20 and the center of the housing 10 is constructed as a connecting line, which is parallel to the height direction of the housing 10. When using the non-contact wide-angle lens fundus field of view measuring device, the non-contact wide-angle lens fundus field of view measuring device can be moved horizontally relative to the wide-angle lens 1 so that the center of the annular scale line 11 is aligned with the observation center of the surgical microscope in the vertical direction, and the left and right eyes are symmetrical in the horizontal direction (the objective lens center of the surgical microscope and the center of the wide-angle lens 1 are collimated, that is, the observation center of the surgical microscope and the center of the wide-angle lens 1 are in an ideal positional relationship).

[0031] Therefore, after determining the position of the maximum field of view of the wide-angle lens 1, the half-field angle and the full-field angle corresponding to the wide-angle lens 1 can be calculated by the horizontal distance between the maximum field of view position and the connecting line and the distance between the maximum field of view position and the aperture stop 20.

[0032] According to some embodiments of the present invention, the inner diameter of the aperture 20 is adjustable. It is understood that the aperture 20 is an adjustable aperture 20, thereby allowing the inner diameter of the aperture 20 to be adjusted to avoid replacing the aperture 20 when simulating pupils of different diameters, thus improving the ease of use of the non-contact wide-angle lens fundus field of view measurement device.

[0033] According to some embodiments of the present invention, the inner diameter of the housing 10 is D, satisfying: 30mm ≤ D ≤ 60mm. In some embodiments, the wide-angle lens 1 has different specifications and sizes, and the inner diameter range of the housing 10 from 30mm to 60mm can cover the relevant size requirements of most commonly used wide-angle lenses 1, enabling the non-contact wide-angle lens fundus field of view measurement device to be used with wide-angle lenses 1 of different specifications to achieve accurate measurement of the fundus field of view. Specifically, the inner diameter of the housing 10 is greater than or equal to 30mm to better approximate infinity (the focal length of the wide-angle lens 1 is very short, generally less than 9mm), while the inner diameter of the housing 10 is less than or equal to 60mm to maintain sufficient observation clarity and resolution. Preferably, the inner diameter of the housing 10 is 50mm.

[0034] According to some embodiments of the present invention, the shell 10 is constructed as a sphere, a cylinder, a polygon, or a cone. It is understood that the shell 10 can be constructed as a sphere, which includes, but is not limited to, a spherical, an ellipsoid, or an irregular sphere; of course, the shell 10 can be constructed as a cylinder, which includes, but is not limited to, a straight cylinder, a conical cylinder, or an irregular cylinder; furthermore, the shell 10 can also be constructed as a polygon, which includes, but is not limited to, a regular polygon or a non-regular polygon; simultaneously, the shell 10 can also be constructed as a cone, which includes, but is not limited to, a cone, a pyramid, or a polygonal cone.

[0035] According to some embodiments of the present invention, the housing 10 is made of a transparent material. It is understood that making the housing 10 of a transparent material facilitates the determination of the maximum field of view position corresponding to the wide-angle lens 1 from the outside, and also facilitates the entry of external light into the housing 10, thereby avoiding the need to set up a light source inside the housing 10, simplifying the structure of the non-contact wide-angle lens fundus field of view measurement device, and reducing the production cost of the non-contact wide-angle lens fundus field of view measurement device.

[0036] Example 2:

[0037] As shown in Figure 3, this application provides a non-contact wide-angle lens fundus field of view measurement method. The measurement method is applicable to the non-contact wide-angle lens fundus field of view measurement device described in Embodiment 1, and includes:

[0038] S100 places the non-contact wide-angle lens fundus field of view measurement device below the wide-angle lens 1.

[0039] S200 adjusts the distance between the wide-angle lens 1 and the non-contact wide-angle lens fundus field of view measurement device.

[0040] S300 observes the relative position of the edge of the aperture 20 and the inner edge of the frame of the wide-angle lens 1. When the edge of the aperture 20 observed by the eyepiece almost overlaps with the inner edge of the frame of the wide-angle lens 1, the distance between the wide-angle lens 1 and the non-contact wide-angle lens fundus field of view measurement device is stopped. The highest position inside the housing 10 that the eyepiece can see is the position of the maximum field of view.

[0041] Based on the inner diameter of the housing 10, the maximum field of view position, and the inner diameter of the aperture 20, S400 calculates the half-field and / or full-field viewing angles.

[0042] The S500 calculates the range of the fundus field of view based on a half-field perspective and fundus field of view conversion model.

[0043] In some embodiments, when measuring the field of view of the wide-angle lens 1 using the non-contact wide-angle lens fundus field of view measuring device described in Embodiment 1, the non-contact wide-angle lens fundus field of view measuring device is first placed below the wide-angle lens 1. Then, the distance between the wide-angle lens 1 and the non-contact wide-angle lens fundus field of view measuring device is adjusted by moving the wide-angle lens 1 or the housing 10. As the wide-angle lens 1 and the housing 10 gradually approach each other, the aperture 20 in the surgical microscope will gradually increase. That is, when moving the wide-angle lens 1 or the housing 10, it is necessary to observe the relative position of the edge of the aperture 20 (the outer periphery of the aperture 20 aperture) and the inner edge of the frame of the wide-angle lens 1 at all times. When the edge of the aperture 20 observed by the eyepiece of the surgical microscope almost overlaps with the inner edge of the frame of the wide-angle lens 1, the movement of the wide-angle lens 1 or the housing 10 is stopped. At this time, the highest position inside the housing 10 that can be seen by the eyepiece of the surgical microscope is the maximum field of view position. That is, the position that can be observed closest to the outer periphery of the inner wall of the housing 10 and the aperture 20 aperture is the maximum field of view position.

[0044] Subsequently, based on the inner diameter of the housing 10, the maximum field of view position, and the inner diameter of the aperture 20, the half-field angle and / or full-field angle are calculated.

[0045] Specifically, the diameter of the housing 10 at the maximum field of view is D, the inner diameter of the aperture 20 is predetermined and the inner diameter of the aperture 20 is d, the distance between the maximum field of view and the aperture 20 is H, and the half-field angle of the wide-angle lens 1 corresponding to the inner diameter of the aperture 20 is a, which satisfies: a=arctan(0.5(Dd) / H).

[0046] Of course, the full field of view corresponding to the wide-angle lens 1 under the inner diameter of the aperture 20 is A, which satisfies: A=2a.

[0047] Finally, based on the half-field perspective and fundus field of view conversion model, the fundus field of view range is calculated.

[0048] Specifically, based on the half-field perspective and fundus field of view conversion model, the fundus field of view range is calculated, including:

[0049] Construct an optical model of the eyeball.

[0050] Understandably, when constructing an optical model of the eyeball, the optical properties of all components of the eyeball (cornea, aqueous humor, lens, vitreous body, etc.) are comprehensively considered, as well as the relative positions and geometry between these components. A simplified geometric optical model is adopted, treating the eyeball as a system composed of multiple optical interfaces and optical media, and using optical principles such as the law of refraction to describe the propagation of light within the eyeball.

[0051] Multiple sets of data on half-field perspective and fundus field of view were obtained based on the eye's optical model.

[0052] In some embodiments, optical simulation software (such as Zemax, Code V, etc.) or a self-written optical calculation program is used to perform ray tracing on the eye's optical model. A series of different half-field viewing angle values ​​are set. For each half-field viewing angle value, multiple rays are emitted into the eye model (the rays enter from outside the cornea, pass through the cornea, pupil, and lens in sequence, and then reach the fundus). The propagation paths of these rays within the eye are tracked until they reach the fundus, and then the corresponding fundus field of view is calculated. This process is repeated to obtain multiple sets of half-field viewing angle and fundus field of view data.

[0053] Multinomial regression was performed on multiple sets of data on half-field perspective and fundus field of view to obtain a fundus field of view conversion model.

[0054] By incorporating the half-field perspective into the fundus field of view conversion model, the range of the fundus field of view is calculated.

[0055] A cubic polynomial was applied to perform polynomial regression on multiple sets of half-field perspective and fundus field of view data to obtain an eye field of view conversion model. The expression of the eye field of view conversion model is as follows:

[0056] FOV=2 (A0+A1 a+A2 a 2 -A3 a 3 );

[0057] Wherein, FOV represents the field of view of the fundus; A0, A1, A2, and A3 are the coefficients after cubic polynomial regression, A0=0.2, A1=1.33, A2=0.001844, and A3=0.0000386; 'a' represents the half-field angle of view corresponding to the inner diameter of the aperture 20 of the wide-angle lens 1. It is worth noting that, based on the same ocular optical model, the maximum and minimum fundus observation ranges under specific field of view angles, different incident positions, and constraints were simulated and calculated to obtain the above calculation results. The maximum tolerance range that may be caused by possible differences in the optical design of the wide-angle lens 1 is also considered. When the field of view angle is 80°–140° (corresponding to a fundus observation range of 108°–178°), the tolerance is ±0.5°. That is, assuming the measurement process is ideal and error-free, when the measured value of the maximum observation range of the wide-angle lens 1 is within this range, the maximum error that may be introduced by the difference in the optical design of the wide-angle lens 1 in the fundus observation range converted from this measurement result is ±0.5°.

[0058] According to some embodiments of the present invention, before adjusting the distance between the wide-angle lens 1 and the non-contact wide-angle lens fundus field of view measuring device, the method further includes:

[0059] Adjust the position of the wide-angle lens 1 and the non-contact wide-angle lens fundus field of view measuring device in the horizontal direction so that the non-contact wide-angle lens fundus field of view measuring device is aligned with the microscope.

[0060] It is understandable that the non-contact wide-angle lens fundus field of view measuring device is collimated with the microscope, that is, in the eyepiece field of view of the surgical microscope, the annular scale line 11 is centered in the vertical direction (the height direction of the housing 10) and is symmetrical to the left and right eyes in the horizontal direction.

[0061] It should be noted that before adjusting the distance between the wide-angle lens 1 and the non-contact wide-angle fundus field of view measuring device, their positions in the horizontal direction should be adjusted to ensure they are aligned with the microscope. This ensures that light propagates along the correct path within the system, laying the foundation for accurate measurement of the fundus field of view. In other words, only when the measuring device is aligned with the microscope can the fundus light reflected from the wide-angle lens 1 accurately enter the non-contact wide-angle fundus field of view measuring device, and the image observed through the surgical microscope be clear, accurate, and representative, thereby improving the accuracy and reliability of the entire measurement process.

[0062] According to some embodiments of the present invention, the non-contact wide-angle lens fundus field of view measurement method further includes: calculating the maximum working distance of the wide-angle lens 1, wherein calculating the maximum working distance of the wide-angle lens 1 includes:

[0063] Obtain the distance between the vertex of the lower surface of the wide-angle lens 1 and the aperture stop 20. The distance between the vertex of the lower surface of the wide-angle lens 1 and the aperture stop 20 is the distance between the wide-angle lens 1 and the entrance pupil plane of the human eye.

[0064] The distance between the wide-angle lens 1 and the corneal vertex is calculated based on the distance between the vertex of the lower surface of the wide-angle lens 1 and the aperture stop 20.

[0065] It is understood that this application can not only measure the field of view of the fundus of the wide-angle lens 1 under different pupil diameters, but also determine the optimal working distance of the wide-angle lens 1 under the corresponding pupil diameter.

[0066] Specifically, after obtaining the maximum field of view position of the wide-angle lens 1 under the corresponding pupil, the distance between the vertex of the lower surface of the wide-angle lens 1 and the aperture stop 20 at this moment is measured. Then, 3mm is subtracted from this distance to obtain the distance between the vertex of the lower surface of the wide-angle lens 1 and the vertex of the cornea at this moment. This distance is the optimal working distance of the wide-angle lens 1 under the corresponding pupil diameter.

[0067] In some embodiments, a liquid of a specific color and easily identifiable substance can be injected into the housing 10. Specifically, when the outer periphery of the aperture 20 observed by the eyepiece of the surgical microscope almost overlaps with the inner edge of the frame of the wide-angle lens 1, liquid is continuously added into the housing 10. When the liquid surface almost coincides with the outer periphery of the aperture 20, the liquid surface is taken as the position of the maximum field of view, thereby making it easy to determine the precise position of the maximum field of view.

[0068] Of course, when using the non-contact wide-angle lens fundus field of view measurement device of this application, the surgical microscope can be combined with a digital imaging device to obtain the eyepiece field of view of the surgical microscope, thereby facilitating the measurement of the wide-angle lens 1 and improving the consistency of the determination of the maximum field of view position.

[0069] It is worth mentioning that when measuring the distance between the maximum field of view position and the aperture stop 20, and when measuring the distance between the vertex of the lower surface of the wide-angle lens 1 and the aperture stop 20, more precise measuring devices such as gratings can be used to improve the measurement precision.

[0070] Therefore, the non-contact wide-angle lens fundus field of view measurement method of the present invention can not only be used to evaluate the quality of the wide-angle lens 1, but also measure the half-field angle and / or full-field angle of the wide-angle lens 1 under different pupil diameters, measure the fundus field of view range of the wide-angle lens 1 under the corresponding pupil diameter, and measure the optimal working distance of the wide-angle lens 1 under the corresponding pupil diameter.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0072] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included 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 non-contact wide-angle lens fundus field-of-view measurement device, characterized in that, include: The housing (10) has a mounting hole at its top end. The inner or outer circumferential wall of the housing (10) has multiple scale lines (11). The multiple scale lines (11) extend circumferentially along the housing (10) and are spaced apart from each other in the axial direction. The aperture (20) is connected to the housing (10) and is located at the mounting hole. The inner diameter of the aperture (20) is d, which satisfies: 4mm≤d≤8mm.

2. The non-contact wide-angle lens fundus field of view measuring device according to claim 1, characterized in that, Some of the scale lines (11) are constructed as annular rings extending circumferentially along the shell (10).

3. The non-contact wide-angle lens fundus field of view measuring device according to claim 1, characterized in that, The inner diameter of the aperture (20) is adjustable.

4. The non-contact wide-angle lens fundus field of view measuring device according to claim 1, characterized in that, The inner diameter of the shell (10) is D, which satisfies: 30mm≤D≤60mm.

5. The non-contact wide-angle lens fundus field of view measuring device according to claim 1, characterized in that, The shell (10) is constructed as a sphere, cylinder, polygon, or cone.

6. The non-contact wide-angle lens fundus field of view measuring device according to claim 1, characterized in that, The housing (10) is made of a transparent material.

7. A method for measuring the field of view of a non-contact wide-angle lens fundus, the method being applicable to the non-contact wide-angle lens fundus field of view measuring device according to any one of claims 1-6, characterized in that, include: The non-contact wide-angle lens fundus field of view measurement device is placed below the wide-angle lens (1); Adjust the distance between the wide-angle lens (1) and the non-contact wide-angle lens fundus field of view measuring device; Observe the relative position of the edge of the aperture (20) and the inner edge of the frame of the wide-angle lens (1). When the edge of the aperture (20) observed by the eyepiece almost overlaps with the inner edge of the frame of the wide-angle lens (1), stop adjusting the distance between the wide-angle lens (1) and the non-contact wide-angle lens fundus field of view measurement device. The highest position inside the housing (10) that the eyepiece can see is the maximum field of view position. Based on the inner diameter of the housing (10), the maximum field of view position and the inner diameter of the aperture (20), calculate the half-field angle and / or the full-field angle. Based on the half-field angle and the fundus field of view conversion model, calculate the fundus field of view range.

8. The method for measuring the field of view of a non-contact wide-angle lens fundus according to claim 7, characterized in that, The step of calculating the fundus field of view based on the half-field perspective and fundus field of view conversion model includes: constructing an ocular optical model; obtaining multiple sets of half-field perspective and fundus field of view data based on the ocular optical model; performing polynomial regression on the multiple sets of half-field perspective and fundus field of view data to obtain the fundus field of view conversion model; and inputting the half-field perspective into the fundus field of view conversion model to calculate the fundus field of view range.

9. The method for measuring the field of view of a non-contact wide-angle lens fundus according to claim 7, characterized in that, Before adjusting the distance between the wide-angle lens (1) and the non-contact wide-angle lens fundus field of view measuring device, the method further includes: adjusting the position between the wide-angle lens (1) and the non-contact wide-angle lens fundus field of view measuring device in the horizontal direction so that the non-contact wide-angle lens fundus field of view measuring device is aligned with the microscope.

10. The method for measuring the field of view of a non-contact wide-angle lens fundus according to claim 8, characterized in that, Also includes: Calculate the maximum working distance of the wide-angle lens (1). The calculation of the maximum working distance of the wide-angle lens (1) includes: obtaining the distance between the vertex of the lower surface of the wide-angle lens (1) and the aperture stop (20). The distance between the vertex of the lower surface of the wide-angle lens (1) and the aperture stop (20) is the distance between the wide-angle lens (1) and the entrance pupil plane of the human eye; and calculate the distance between the wide-angle lens (1) and the vertex of the cornea based on the distance between the vertex of the lower surface of the wide-angle lens (1) and the aperture stop (20).

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