Corneal depth positioning method, device, equipment and storage medium

Abstract

This application discloses a corneal depth localization method, apparatus, device, and storage medium, relating to the field of optical technology. The disclosed method includes: in response to initial parameters input by a user, acquiring an initial optical simulation system formed by at least two virtual optical elements; determining the position information of each virtual optical element in the initial optical simulation system based on the initial parameters to obtain a target optical simulation system; adjusting the position information of the corresponding optical elements in the actual scene based on the target optical simulation system to obtain a target optical system; constructing an optical system based on the target optical simulation system; and determining the target corneal depth corresponding to the current spot position formed on the detector surface through the optical system. Thus, when changing devices, only initial parameters need to be input to construct the corresponding optical system in the new device for corneal depth localization, effectively reducing the product development cycle.

Description

Technical Field

[0001] This application relates to the field of optical technology, and in particular to a method, apparatus, device and storage medium for corneal depth positioning. Background Technology

[0002] As one of the most important refractive media in the eye, the precise measurement of the cornea's morphology and biomechanical properties is crucial for the early diagnosis of ophthalmic diseases, treatment planning, and postoperative outcome evaluation. Among various ophthalmic diagnostic devices, obtaining accurate depth information of the corneal surface and interior is a core component. For example, corneal topography requires reconstructing the three-dimensional morphology of the corneal surface, while optical coherence tomography (OCT) scanners need to locate the interfaces between different corneal tissue layers. The accuracy of corneal depth localization determines the reliability of all subsequent diagnostic parameters.

[0003] Currently, common methods for corneal depth localization involve using a laser and a position-sensitive detector within the optical system. The laser beam is incident on the corneal surface at a specific angle, creating a reflected spot. This reflected light is collected by a receiving lens group and imaged onto the detector surface. When the cornea shifts in the depth direction, the actual change in corneal depth is deduced from the position of the spot on the detector.

[0004] However, ophthalmic devices with different functions, such as corneal topography systems and anterior chamber depth analyzers, often have significantly different requirements for measurement window size, working distance, measurement range, and accuracy. In actual R&D, the lens group position, angle, and other parameters of an optical system designed and optimized for a specific device are determined based on the needs of that particular device. When it is necessary to design an optical system for corneal positioning for another device with different parameter requirements, the solution previously designed for that specific device usually cannot be directly applied. Optical engineers must recalculate the optical path, manually adjust and optimize it for the parameters of the other device, and design a corresponding optical system, resulting in a large amount of repetitive work and extending the product development cycle. Summary of the Invention

[0005] The main objective of this application is to provide a corneal depth positioning method, device, equipment, and storage medium, aiming to solve the technical problem that when replacing equipment in the prior art, a large amount of repetitive labor is required to design the corresponding optical system, resulting in a long product development cycle.

[0006] To achieve the above objectives, this application proposes a corneal depth localization method, the method comprising: In response to initial parameters input by the user, an initial optical simulation system consisting of at least two virtual optical elements is obtained; Based on the initial parameters, the position information of each virtual optical element in the initial optical simulation system is determined to obtain the target optical simulation system; An optical system is constructed based on the target optical simulation system, wherein the optical elements in the optical system correspond to each of the virtual optical elements, and the positions of each of the optical elements correspond to the corresponding virtual optical elements; The optical system determines the target corneal depth corresponding to the current spot position formed on the detector surface.

[0007] In one embodiment, the initial parameters include at least the viewing distance and the window width, and the virtual optical elements include at least a virtual light source, a virtual projection lens, and a virtual receiving lens. The step of determining the position information of each of the virtual optical elements in the initial optical simulation system based on the initial parameters to obtain the target optical simulation system includes: The corneal vertex position information and the incident angle threshold of the virtual light source are determined based on the eye-to-eye distance and the window width. The position information of the virtual light source is determined based on the incident angle threshold; The first search range of the virtual projection lens and the second search range of the virtual receiving lens are determined based on the corneal vertex position information. Determine the position information of the virtual projection lens within the first search range; The position information of the virtual receiving lens is determined within the second described range; The target optical simulation system is determined based on the position information of the virtual light source, the position information of the virtual projection lens, and the position information of the virtual receiving lens.

[0008] In one embodiment, the step of determining the position information of the virtual projection lens within the first search range includes: Within the first search range, control the virtual projection lens to move along the optical axis; Record the radius of the light spot formed on the virtual corneal surface by the laser beam emitted by the light source through the virtual projection lens when the virtual projection lens is in different positions; The position of the virtual projection lens when the radius of the light spot formed on the virtual corneal surface reaches its minimum value will be used as the position information of the virtual projection lens.

[0009] In one embodiment, the virtual optical element further includes a virtual detector, and the step of determining the position information of the virtual receiving lens within the second said range includes: Within the second search range, the virtual receiving lens is controlled to move along the optical axis and rotate within a preset angle range; Record the radius of the laser beam reflected by the virtual cornea and formed on the surface of the virtual detector by the virtual receiving lens when the virtual receiving lens is in different positions and at different angles; The position of the virtual receiving lens is used as the position information of the virtual receiving lens when the radius of the light spot formed on the surface of the virtual detector is minimized and the object plane, the principal plane of the lens, and the image plane intersect on the same straight line.

[0010] In one embodiment, the step of determining the target corneal depth corresponding to the current spot position formed on the detector surface by the optical system includes: A laser beam is emitted onto the current corneal surface through a light source in the optical system; The position of the current spot formed on the detector surface by the receiving lens after the laser beam is reflected from the current corneal surface is obtained; Obtain the target mapping relationship, which is constructed based on the target optical simulation system and characterizes the correspondence between corneal depth and spot position; The target corneal depth corresponding to the current spot position is determined by the target mapping relationship.

[0011] In one embodiment, before the step of obtaining the target mapping relationship, the method further includes: In the target optical simulation system, the virtual cornea is sequentially placed at positions corresponding to multiple preset depths; At each of the preset depths, the position of the light spot formed on the surface of the virtual detector by the virtual receiving lens after the laser beam of the virtual light source is reflected by the corneal surface; Based on the preset depths and corresponding spot positions, a target mapping relationship between corneal depth and spot position is constructed.

[0012] In one embodiment, the step of constructing a target mapping relationship between corneal depth and spot position based on each preset depth and the corresponding spot position includes: An initial mapping relationship between corneal depth and spot position is constructed based on each preset depth and the corresponding spot position; The initial spot position formed on the surface of the virtual detector when the virtual cornea is on a preset reference plane is obtained; The zero-point offset is determined based on the difference between the initial spot position and the preset spot position; The initial mapping relationship is corrected based on the zero-point offset to obtain the target mapping relationship.

[0013] Furthermore, to achieve the above objectives, this application also proposes a corneal depth positioning device, the device comprising: The data receiving module is used to acquire an initial optical simulation system consisting of at least two virtual optical elements in response to initial parameters input by the user. The system simulation module is used to determine the position information of each virtual optical element in the initial optical simulation system based on the initial parameters, so as to obtain the target optical simulation system; The system construction module is used to construct an optical system based on the target optical simulation system, wherein the optical elements in the optical system correspond to each of the virtual optical elements, and the positions of each of the optical elements correspond to the corresponding virtual optical elements; The depth positioning module is used to determine the target corneal depth corresponding to the current spot position formed on the detector surface through the optical system.

[0014] In addition, to achieve the above objectives, this application also proposes a corneal depth positioning device, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the corneal depth positioning method as described above.

[0015] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the corneal depth positioning method described above.

[0016] One or more technical solutions proposed in this application have at least the following technical effects: This application obtains an initial optical simulation system composed of at least two virtual optical elements in response to user-inputted initial parameters; determines the position information of each virtual optical element in the initial optical simulation system based on the initial parameters to obtain a target optical simulation system; adjusts the position information of the corresponding optical elements in the actual scene based on the target optical simulation system to obtain the target optical system; constructs an optical system based on the target optical simulation system, where the optical elements in the optical system correspond to each virtual optical element, and the positions of each optical element correspond to the corresponding virtual optical elements; and determines the target corneal depth corresponding to the current spot position formed on the detector surface through the optical system. This application determines the position information of each virtual optical element in the initial optical simulation system using user-inputted initial parameters, and uses the obtained target optical simulation system to construct an optical system in the actual scene for corneal depth localization. Therefore, when changing equipment, only the initial parameters need to be input to construct the corresponding optical system in the new equipment, eliminating the need for extensive repetitive work such as optical path calculations, manual debugging, and optimization, effectively reducing the product development cycle. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart illustrating the first embodiment of the corneal depth positioning method of this application; Figure 2 This is a flowchart illustrating the second embodiment of the corneal depth positioning method of this application; Figure 3 This is a flowchart illustrating the third embodiment of the corneal depth positioning method of this application; Figure 4 This is a schematic diagram of corneal depth measurement in the third embodiment of this application; Figure 5 This is a schematic diagram of the module structure of the corneal depth positioning device of this application; Figure 6 This is a schematic diagram of the corneal depth positioning device of this application.

[0020] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0021] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0022] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0023] The main solution of this application embodiment is as follows: In response to the initial parameters input by the user, an initial optical simulation system formed by at least two virtual optical elements is obtained; the position information of each virtual optical element in the initial optical simulation system is determined according to the initial parameters to obtain a target optical simulation system; the position information of the corresponding optical elements in the actual scene is adjusted according to the target optical simulation system to obtain a target optical system; an optical system is constructed based on the target optical simulation system, wherein the optical elements in the optical system correspond to each virtual optical element, and the position of each optical element corresponds to the position of the corresponding virtual optical element; the target corneal depth corresponding to the current spot position formed on the detector surface is determined through the optical system.

[0024] Because existing technologies require a lot of repetitive work to design corresponding optical systems when replacing equipment, product development cycles are long.

[0025] This application provides a solution that determines the position information of each virtual optical element in the initial optical simulation system by using initial parameters input by the user. The obtained target optical simulation system is then used to construct an optical system in the actual scene for corneal depth positioning. Thus, when changing devices, only the initial parameters need to be input to construct the corresponding optical system in the new device, eliminating the need for a large amount of repetitive work such as optical path calculation, manual debugging and optimization, and effectively reducing the product development cycle.

[0026] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, or mobile phone, or an electronic device or corneal depth positioning device capable of performing the above functions. The following description uses a corneal depth positioning device (hereinafter referred to as the positioning device) as an example to illustrate this embodiment and the subsequent embodiments.

[0027] Based on this, embodiments of this application provide a corneal depth localization method, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the corneal depth positioning method of this application.

[0028] In this embodiment, the corneal depth localization method includes steps S10 to S40: Step S10: In response to the initial parameters input by the user, obtain an initial optical simulation system formed by at least two virtual optical elements.

[0029] It should be noted that the initial parameters can be parameters used to adjust the positional relationships of virtual optical elements in the initial optical simulation system.

[0030] Understandably, virtual optical elements can be digital models built in optical simulation software to simulate actual optical devices.

[0031] Accordingly, the initial optical simulation system can be a simulation system that has not yet been optimized and consists of at least two virtual optical elements combined according to a preset topology.

[0032] In a specific implementation, the positioning device can receive initial parameters input by the user through the interface of optical simulation software (such as ZEMAX software), and in response to the initial parameters, load the initial optical simulation system pre-formed by at least two virtual optical elements.

[0033] Step S20: Determine the position information of each virtual optical element in the initial optical simulation system according to the initial parameters to obtain the target optical simulation system.

[0034] In its implementation, a virtual cornea simulating the cornea is pre-constructed in the initial optical simulation system. The positioning device uses initial parameters to determine the spatial position of the virtual corneal vertex within the initial optical simulation system, as well as the angular constraint range of the light beam within the system. Subsequently, within the angular constraint range, using the spatial position of the virtual corneal vertex as a reference, the spatial positions of each virtual optical element within the initial optical simulation system are determined, ensuring that the virtual optical elements meet preset optical performance conditions. The positioning device can then adjust the positional relationships of each performance element based on the determined spatial positions to obtain the target optical simulation system.

[0035] Step S30: Construct an optical system based on the target optical simulation system.

[0036] The optical elements in the optical system correspond to each of the virtual optical elements, and the positions of each optical element and the corresponding virtual optical element correspond.

[0037] It should be noted that the optical system can be a real-world system used for corneal depth positioning. This optical system can be composed of actual optical elements, which correspond to the virtual optical elements in the target optical simulation system.

[0038] In a practical implementation, the positioning device can extract the position information of each virtual optical element from the target optical simulation system. The position information includes the spatial coordinates and angles of each virtual optical element in the simulation system. Then, based on the extracted position information, the installation position of the optical element corresponding to each virtual optical element in the actual optical system is determined. The actual optical element may include a light source, a projection lens, a receiving lens, and a detector. According to the determined installation position, each optical element is assembled into an actual usable optical system.

[0039] Step S40: Determine the target corneal depth corresponding to the current spot position formed on the detector surface through the optical system.

[0040] It should be noted that the detector can be located at the end of the receiving optical path to receive the light beam reflected from the corneal surface and imaged by the receiving lens, forming a light spot.

[0041] In a practical implementation, a light source in the optical system emits a light beam, which is projected onto the corneal surface after passing through a projection lens. The corneal surface reflects the light beam, and the reflected light is imaged onto the detector surface in the optical system after passing through a receiving lens, forming a light spot. The detector senses changes in the position of the light spot on its sensitive surface and outputs a corresponding position signal. The positioning device can determine the current position of the light spot using this position signal and determine the corresponding target corneal depth based on the correspondence between the light spot position and corneal depth.

[0042] This embodiment obtains an initial optical simulation system composed of at least two virtual optical elements in response to user-inputted initial parameters; determines the position information of each virtual optical element in the initial optical simulation system based on the initial parameters, thus obtaining a target optical simulation system; adjusts the position information of the corresponding optical elements in the actual scene based on the target optical simulation system, thus obtaining the target optical system; constructs an optical system based on the target optical simulation system, where the optical elements in the optical system correspond to each virtual optical element, and the positions of each optical element correspond to the corresponding virtual optical elements; and determines the target corneal depth corresponding to the current spot position formed on the detector surface through the optical system. This embodiment determines the position information of each virtual optical element in the initial optical simulation system using user-inputted initial parameters, and uses the obtained target optical simulation system to construct an optical system in the actual scene for corneal depth positioning. Therefore, when changing devices, only the initial parameters need to be input to construct the corresponding optical system in the new device, eliminating the need for a large amount of repetitive work such as optical path calculation, manual debugging and optimization, effectively reducing the product development cycle.

[0043] Based on the first embodiment of this application, a second embodiment of this application is proposed. In the second embodiment, content that is the same as or similar to that in the first embodiment described above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 2 , Figure 2 This is a flowchart illustrating the second embodiment of the corneal depth positioning method of this application.

[0044] In this embodiment, the initial parameters include at least the viewing distance and the window width, and the virtual optical element includes at least a virtual light source, a virtual projection lens, and a virtual receiving lens. Step S20 includes steps S201 to S206: Step S201: Determine the corneal vertex position information and the incident angle threshold of the virtual light source based on the eye-to-eye distance and the window width.

[0045] It should be noted that the eye-to-eye distance can be the distance from the front end of the positioning device to the apex of the cornea.

[0046] Understandably, the window width can be the size of the opening on the front surface of the positioning device for light to enter and exit.

[0047] In the specific implementation, the positioning device establishes a spatial coordinate system with the preset reference point in the initial optical simulation system as the origin. Based on the viewing distance, the position coordinates of the pre-constructed virtual corneal vertex in the spatial coordinate system are determined. These coordinates represent the corneal vertex's position information; the virtual corneal vertex is located on the optical axis of the spatial coordinate system, and its distance from the origin is equal to the viewing distance. Simultaneously, based on the window width and the viewing distance, the incident angle threshold of the virtual light source is calculated using geometric relationships. The incident angle threshold represents the maximum allowable angle between the beam emitted by the virtual light source and the optical axis.

[0048] The incident angle threshold can be calculated using the following preset angle formula:

[0049] In the formula, The incident angle threshold, For window width, This refers to the distance between the eyes and the camera.

[0050] Step S202: Determine the position information of the virtual light source based on the incident angle threshold.

[0051] In practical implementation, within the constraint range of the incident angle threshold, the positioning device determines the position coordinates of the virtual light source in the spatial coordinate system based on the preset optical path length and the corneal vertex position information, thereby obtaining the position information of the virtual light source. The position information of the virtual light source satisfies the following conditions: the angle between the line connecting the virtual light source and the virtual corneal vertex and the optical axis is not greater than the incident angle threshold, and the distance between the virtual light source and the virtual corneal vertex is equal to the preset optical path length.

[0052] Step S203: Determine the first search range of the virtual projection lens and the second search range of the virtual receiving lens based on the corneal vertex position information.

[0053] In practical implementation, the positioning device can construct a virtual projection lens that simulates a real projection lens and a virtual receiving lens that simulates a real receiving lens in optical simulation software. The virtual projection lens is located between the virtual light source and the virtual cornea, and is used to project the laser beam emitted by the virtual light source to form a light spot on the surface of the virtual cornea; the virtual receiving lens is located between the virtual detector and the virtual cornea, and is used to project the laser beam reflected from the surface of the virtual cornea onto the surface of the virtual detector.

[0054] Furthermore, the positioning device uses the corneal apex position information as a reference and sets a first preset offset range and a second preset offset range along the optical axis. The first preset offset range is used to limit the axial movement range of the virtual projection lens relative to the corneal apex, obtaining a first search range for the virtual projection lens; the second preset offset range is used to limit the axial movement range of the virtual receiving lens relative to the corneal apex, obtaining a second search range for the virtual receiving lens. Simultaneously, the angle search range of the virtual receiving lens is set according to the incident angle threshold.

[0055] Step S204: Determine the position information of the virtual projection lens within the first search range.

[0056] In a specific implementation, the positioning device can control the movement of the virtual projection lens within the first search range to determine the position where the radius of the light spot formed by the laser beam emitted by the light source on the virtual corneal surface through the virtual projection lens meets the corresponding conditions, thereby obtaining the position information of the virtual projection lens.

[0057] In one feasible implementation, step S204 may include steps S2041 to S2043: Step S2041: Control the virtual projection lens to move along the optical axis within the first search range.

[0058] In the specific implementation, the positioning device controls the virtual projection lens to move along the optical axis within the first search range. During the movement, the spatial position of the virtual projection lens is gradually changed according to a preset step size.

[0059] Step S2042: Record the radius of the light spot formed on the virtual corneal surface by the laser beam emitted by the light source through the projection lens when the virtual projection lens is in different positions.

[0060] In the specific implementation, the positioning device calls the ray tracing function of the optical simulation software every time the virtual projection lens moves to a position, calculates the light spot formed by the laser beam emitted by the virtual light source being projected onto the virtual corneal surface after passing through the virtual projection lens, and obtains the radius value of the light spot.

[0061] Step S2043: The position of the virtual projection lens when the radius of the light spot formed on the virtual corneal surface reaches its minimum value is taken as the position information of the virtual projection lens.

[0062] In the specific implementation, after the positioning device has traversed all positions within the first search range, it compares the recorded radii of each light spot to determine the minimum value. The position of the virtual projection lens corresponding to this minimum value is then determined as the position information of the virtual projection lens in the target optical simulation system.

[0063] Step S205: Determine the position information of the virtual receiving lens within the second described range.

[0064] In a specific implementation, the positioning device can control the movement of the virtual receiving lens within the second search range to determine the position where the laser beam reflected by the virtual cornea forms a spot radius on the surface of the virtual detector that meets the corresponding conditions, thereby obtaining the position information of the virtual receiving lens.

[0065] In one feasible implementation, the virtual optical element further includes a virtual detector, and step S205 may include steps S2051 to S2053: Step S2051: Within the second search range, control the virtual receiving lens to move on the optical axis and control the virtual receiving lens to rotate within a preset angle range.

[0066] It should be noted that the preset angle range can be the angle rotation range pre-configured for the actual receiving lens.

[0067] In its implementation, the positioning device, within the second search range, controls the virtual receiving lens to move along the optical axis; simultaneously, it controls the virtual receiving lens to rotate within a preset angle range around a direction perpendicular to the optical axis. During the movement and rotation, the spatial position and angle of the virtual receiving lens are gradually changed according to preset step sizes.

[0068] Step S2052: Record the radius of the light spot formed on the surface of the virtual detector by the laser beam reflected by the virtual cornea when the virtual receiving lens is in different positions and at different angles.

[0069] In the specific implementation, the positioning device calls the ray tracing function of the optical simulation software every time the virtual receiving lens moves to a position and rotates to an angle, calculates the light spot formed by the laser beam emitted by the virtual light source after being reflected by the virtual corneal surface and imaged on the surface of the virtual detector through the virtual receiving lens, and obtains the radius value of the light spot.

[0070] Step S2053: When the radius of the light spot formed on the surface of the virtual detector reaches the minimum value and the object plane, the principal plane of the lens, and the image plane intersect on the same straight line, the position of the virtual receiving lens is taken as the position information of the virtual receiving lens.

[0071] In practical implementation, after traversing all positions within the second search range and all angles within the preset angle range, the positioning device compares the recorded spot radius values ​​and determines the minimum value. Simultaneously, from the positions and angles that satisfy the minimum value condition, it selects the state where the extensions of the object plane, the lens principal plane, and the image plane intersect on the same straight line. The position and angle of the virtual receiving lens corresponding to this state are then determined as the position and angle information of the virtual receiving lens in the target optical simulation system.

[0072] Step S206: Determine the target optical simulation system based on the position information of the virtual light source, the position information of the virtual projection lens, and the position information of the virtual receiving lens.

[0073] In practice, after determining the position information of the virtual light source, the virtual projection lens, and the virtual receiving lens, the positioning device uses the optical simulation system composed of the virtual light source, the virtual projection lens, and the virtual receiving lens at the corresponding positions as the target optical simulation system.

[0074] This embodiment determines the corneal vertex position information and the incident angle threshold of the virtual light source by using the viewing distance and window width; determines the position information of the virtual light source based on the incident angle threshold; determines the first search range of the virtual projection lens and the second search range of the virtual receiving lens based on the corneal vertex position information; determines the position information of the virtual projection lens within the first search range; determines the position information of the virtual receiving lens within the second search range; and determines the target optical simulation system based on the position information of the virtual light source, the virtual projection lens, and the virtual receiving lens. This achieves accurate determination of the position information of each virtual optical element in the initial optical simulation system, effectively improving the construction accuracy of the target optical simulation system.

[0075] Based on the first and second embodiments of this application, a third embodiment of this application is proposed. In this third embodiment, content that is the same as or similar to the first and second embodiments described above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 3 , Figure 3 This is a flowchart illustrating the third embodiment of the corneal depth positioning method of this application.

[0076] In this embodiment, step S40 may include steps S401 to S404: Step S401: A laser beam is emitted onto the current corneal surface through the light source in the optical system.

[0077] In practice, after the optical system is assembled, when corneal depth measurement is required, the positioning device can control the light source in the optical system to emit a laser beam, which is then projected onto the current corneal surface through the projection lens.

[0078] Step S402: Obtain the current position of the light spot formed on the detector surface by the receiving lens after the laser beam is reflected from the current corneal surface.

[0079] In practice, the laser beam is reflected from the corneal surface, and the reflected light is collected by a receiving lens and imaged onto the detector surface, forming the current light spot. The positioning device can then determine the position of the current light spot formed on the detector surface.

[0080] Step S403: Obtain the target mapping relationship.

[0081] The target mapping relationship is constructed based on the target optical simulation system and characterizes the correspondence between corneal depth and spot position.

[0082] In practice, the positioning device can collect a large amount of corneal depth data and spot position data in advance using the constructed target relationship simulation system. The collected corneal depth data and spot position data are then fitted to determine the target mapping relationship that characterizes the correspondence between corneal depth and spot position.

[0083] Step S404: Determine the target corneal depth corresponding to the current spot position through the target mapping relationship.

[0084] In practice, the positioning device searches for the corresponding corneal depth in the target mapping relationship based on the current spot position to obtain the target corneal depth.

[0085] In this embodiment, steps S41 to S43 are included before step S403: Step S41: In the target optical simulation system, the virtual cornea is sequentially placed at multiple positions corresponding to preset depths.

[0086] In a specific implementation, the positioning device can control the virtual corneal model to move along the optical axis in the target optical simulation system through optical simulation software, and place the virtual cornea in a sequence at positions corresponding to multiple preset depths. The multiple preset depths cover a preset measurement range, and the preset depths are distributed at preset step intervals.

[0087] Step S42: At each of the preset depths, obtain the position of the light spot formed on the surface of the virtual detector by the virtual receiving lens after the laser beam of the virtual light source is reflected by the corneal surface.

[0088] In practice, when the virtual cornea moves to a preset depth position, the positioning device uses the ray tracing function of the optical simulation software to calculate the light spot formed by the laser beam emitted by the virtual light source after being reflected by the virtual cornea surface at the current depth and imaged onto the surface of the virtual detector by the virtual receiving lens, and obtains the position coordinates of the light spot on the surface of the virtual detector.

[0089] Step S43: Construct a target mapping relationship between corneal depth and spot position based on each preset depth and the corresponding spot position.

[0090] In its implementation, after acquiring the spot positions at all preset depth locations, the positioning device establishes a correspondence between corneal depth and the spot positions on the detector surface based on the recorded multiple preset depth values ​​and the corresponding spot position coordinates, thus obtaining a target mapping relationship. This target mapping relationship is represented by a data table, curve, or function to characterize the correspondence between corneal depth and spot positions.

[0091] In one feasible implementation, step S43 may include steps S431 to S434: Step S431: Construct an initial mapping relationship between corneal depth and spot position based on each preset depth and the corresponding spot position.

[0092] In practice, the positioning device can use the correspondence between corneal depth and spot position directly constructed based on each preset depth and the corresponding spot position as the initial mapping relationship that has not yet been corrected.

[0093] Step S432: Obtain the initial spot position formed on the surface of the virtual detector when the virtual cornea is on the preset reference plane.

[0094] In practical implementation, the virtual cornea can be placed at a preset reference plane position in the target optical simulation system. The preset reference plane corresponds to the reference position where the corneal depth is zero. The positioning device uses the ray tracing function of the optical simulation software to calculate the light spot formed on the surface of the virtual detector by the laser beam emitted by the virtual light source after being reflected by the virtual cornea surface and passing through the virtual receiving lens. The device then obtains the position coordinates of this light spot on the surface of the virtual detector as the initial light spot position.

[0095] Step S433: Determine the zero-point offset based on the difference between the initial spot position and the preset spot position.

[0096] In practical implementation, the positioning device can obtain a pre-set preset spot position, which is the theoretical position where the spot should be on the surface of the virtual detector when the virtual cornea is on a preset reference plane. The difference between the initial spot position and the preset spot position is calculated, and this difference is determined as the zero-point offset.

[0097] Step S434: Correct the initial mapping relationship according to the zero-point offset to obtain the target mapping relationship.

[0098] In practical implementation, the positioning device can apply the zero-point offset to the initial mapping relationship, performing an overall translation correction on the initial mapping relationship. This ensures that when the virtual cornea is on a preset reference plane, the spot position corresponding to the corrected mapping relationship is consistent with the preset spot position, and the output depth value is zero. The corrected mapping relationship is the target mapping relationship, used to characterize the correspondence between corneal depth and the spot position on the detector surface in actual measurements.

[0099] Furthermore, for ease of understanding, refer to Figure 4 , Figure 4 This is a schematic diagram of corneal depth measurement in the third embodiment of this application. When the corneal apex is located at point A on a preset reference plane, the laser beam emitted by the light source forms a spot on the corneal apex (i.e., point A) through the projection lens. The reflected light from the corneal apex forms a spot on the detector surface at point C through the receiving lens, forming a reflected beam AC. The angle between the laser beam and the normal to the preset reference plane is γ, the angle between the reflected beam AC and the normal to the preset reference plane is α, the angle between the reflected beam AC and the detector surface is β, and the distance between point A and the optical center O of the receiving lens is b.

[0100] When the corneal apex is located at point B on the actual plane, the laser beam emitted by the light source forms a spot at the corneal apex (i.e., point B) through the projection lens. The reflected light from the corneal apex forms a spot at point D on the detector surface through the receiving lens, forming the reflected beam BD. The displacement of the spot position relative to point C is x, and the corneal depth is y.

[0101] Draw the extension of AC and the perpendicular line to AC from B and D respectively, with the feet of the perpendiculars at E and F. According to the triangle theorem, we can obtain:

[0102] Among them, it can be seen from the figure that DF=xsinβ, BE=ABsin (α+γ), PC=a, PA=b, FC=xcosβ, AE=ABcos (α+γ), AB=y / cosγ.

[0103] Furthermore, when the focal length f of the imaging lens group is known, according to Gaussian imaging theorem:

[0104] Substituting the parameters into the above equation and rearranging, we can obtain the theoretical function of the change in the initial spot position with corneal depth under ideal conditions:

[0105] Using the aforementioned theoretical function, under theoretical conditions, when the change in the light spot position on the detector surface compared to the preset light spot position (corresponding to point C in the figure) is known, the corresponding corneal depth can be determined. If the preset light spot position is known, the corresponding corneal depth can be determined based on the light spot position on the detector surface.

[0106] It should be understood that during actual assembly or simulation, due to factors such as mechanical tolerances and component position deviations, the actual initial spot position formed when the cornea is on the preset reference plane deviates from the preset spot position, resulting in the relationship between the actual measured spot position and corneal depth being shifted by a fixed offset relative to the theoretical function.

[0107] The zero-point offset is determined by calculating the difference between the initial spot position and the theoretically preset spot position. This zero-point offset is then applied to correct the initial mapping relationship. Essentially, this translates the spot position data in the actual measurement coordinate system to the coordinate system defined by the theoretical function, ensuring that the corrected target mapping relationship coincides with the theoretical function at the zero point. This ensures that subsequent calculations based on the spot position to infer corneal depth can be directly performed based on the physical laws described by the theoretical function, thereby eliminating the influence of systematic deviations on the measurement results and ensuring that the actual measurement relationship remains consistent with the theoretical design expectations.

[0108] Furthermore, in a target optical simulation system, the positioning device can sequentially place a virtual cornea at multiple verification depth positions and acquire the position of the light spot on the virtual detector surface corresponding to each verification depth through ray tracing. Based on the target mapping relationship, the acquired light spot positions are converted into corresponding depth calculation values. These depth calculation values ​​are then compared with the corresponding verification depth values ​​to calculate the deviation at each point. The linearity index of the target mapping relationship is determined based on the ratio of the maximum deviation value to the full-scale measurement range. The linearity index measures the quality of the linear relationship between corneal depth and light spot position; a smaller value indicates a better linear relationship.

[0109] If the linearity index exceeds the preset threshold, it indicates that the linearity of the target mapping relationship does not meet the requirements. In this case, it is necessary to adjust the magnification of the projection lens in the target optical simulation system and return to the step of determining the position information of each virtual optical element in the initial optical simulation system according to the initial parameters to obtain the target optical simulation system. Repeat the above process until the linearity index is less than or equal to the preset threshold and meets the preset requirements, so as to effectively improve the accuracy of corneal depth measurement.

[0110] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the corneal depth positioning method of this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0111] This application also provides a corneal depth positioning device; please refer to... Figure 5 , Figure 5 This is a schematic diagram of the module structure of the corneal depth positioning device of this application. The corneal depth positioning device includes: The data receiving module 10 is used to acquire an initial optical simulation system formed by at least two virtual optical elements in response to initial parameters input by the user.

[0112] The system simulation module 20 is used to determine the position information of each virtual optical element in the initial optical simulation system according to the initial parameters, so as to obtain the target optical simulation system.

[0113] The system construction module 30 is used to construct an optical system based on the target optical simulation system, wherein the optical elements in the optical system correspond to each of the virtual optical elements, and the positions of each of the optical elements correspond to the corresponding virtual optical elements.

[0114] The depth positioning module 40 is used to determine the target corneal depth corresponding to the current spot position formed on the detector surface through the optical system.

[0115] The corneal depth positioning device provided in this application, employing the corneal depth positioning method described in the above embodiments, can solve the technical problem of long product development cycles caused by the need for extensive repetitive labor in designing corresponding optical systems when replacing equipment in the prior art. Compared with the prior art, the beneficial effects of the corneal depth positioning device provided in this application are the same as those of the corneal depth positioning method provided in the above embodiments, and other technical features in the corneal depth positioning device are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0116] This application provides a corneal depth positioning device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, which are executed by the at least one processor to enable the at least one processor to perform the corneal depth positioning method in the first embodiment described above.

[0117] The following is for reference. Figure 6 , Figure 6This is a schematic diagram of the corneal depth positioning device of this application. The corneal depth positioning device in the embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle terminals (such as vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 6 The corneal depth positioning device shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.

[0118] like Figure 6 As shown, the corneal depth positioning device may include a processing unit 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1002 or a program loaded from a storage device 1003 into a random access memory (RAM) 1004. The RAM 1004 also stores various programs and data required for the operation of the corneal depth positioning device. The processing unit 1001, ROM 1002, and RAM 1004 are interconnected via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touchscreen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 1003 including, for example, magnetic tape, hard disk, etc.; and communication devices 1009. Communication device 1009 allows the corneal depth positioning device to communicate wirelessly or wiredly with other devices to exchange data. Although the figures show corneal depth positioning devices with various systems, it should be understood that implementation or possession of all the systems shown is not required. More or fewer systems may be implemented alternatively.

[0119] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from ROM 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.

[0120] The corneal depth positioning device provided in this application, employing the corneal depth positioning method described in the above embodiments, can solve the technical problem of long product development cycles caused by the need for extensive repetitive labor in designing corresponding optical systems when replacing existing equipment. Compared with the prior art, the beneficial effects of the corneal depth positioning device provided in this application are the same as those of the corneal depth positioning method provided in the above embodiments, and other technical features of this corneal depth positioning device are the same as those disclosed in the previous embodiment method, and will not be repeated here.

[0121] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0122] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0123] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the corneal depth positioning method in the above embodiments.

[0124] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0125] The aforementioned computer-readable storage medium may be included in the corneal depth positioning device; or it may exist independently and not assembled into the corneal depth positioning device.

[0126] The aforementioned computer-readable storage medium carries one or more programs. When these programs are executed by the corneal depth positioning device, the corneal depth positioning device: in response to initial parameters input by the user, acquires an initial optical simulation system formed by at least two virtual optical elements; determines the position information of each virtual optical element in the initial optical simulation system based on the initial parameters, thereby obtaining a target optical simulation system; adjusts the position information of the corresponding optical elements in the actual scene based on the target optical simulation system, thereby obtaining a target optical system; constructs an optical system based on the target optical simulation system, wherein the optical elements in the optical system correspond to each virtual optical element, and the position of each optical element corresponds to the position of the corresponding virtual optical element; and determines the target corneal depth corresponding to the current spot position formed on the detector surface through the optical system.

[0127] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a Local Area Network (LAN) or a Wide Area Network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0128] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0129] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0130] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the corneal depth positioning method described above. This solves the technical problem in the prior art where replacing equipment requires extensive repetitive work to design the corresponding optical system, resulting in a long product development cycle. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as those of the corneal depth positioning method provided in the above embodiments, and will not be repeated here.

[0131] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A method for corneal depth localization, characterized in that, The method includes: In response to initial parameters input by the user, an initial optical simulation system consisting of at least two virtual optical elements is obtained; Based on the initial parameters, the position information of each virtual optical element in the initial optical simulation system is determined to obtain the target optical simulation system; An optical system is constructed based on the target optical simulation system, wherein the optical elements in the optical system correspond to each of the virtual optical elements, and the positions of each of the optical elements correspond to the corresponding virtual optical elements; The optical system determines the target corneal depth corresponding to the current spot position formed on the detector surface.

2. The corneal depth localization method as described in claim 1, characterized in that, The initial parameters include at least the viewing distance and the window width, and the virtual optical elements include at least a virtual light source, a virtual projection lens, and a virtual receiving lens. The step of determining the position information of each of the virtual optical elements in the initial optical simulation system based on the initial parameters to obtain the target optical simulation system includes: The corneal vertex position information and the incident angle threshold of the virtual light source are determined based on the viewing distance and the window width. The position information of the virtual light source is determined based on the incident angle threshold; The first search range of the virtual projection lens and the second search range of the virtual receiving lens are determined based on the corneal vertex position information. Determine the position information of the virtual projection lens within the first search range; The position information of the virtual receiving lens is determined within the second described range; The target optical simulation system is determined based on the position information of the virtual light source, the position information of the virtual projection lens, and the position information of the virtual receiving lens.

3. The corneal depth localization method as described in claim 2, characterized in that, The step of determining the position information of the virtual projection lens within the first search range includes: Within the first search range, control the virtual projection lens to move along the optical axis; Record the radius of the light spot formed on the virtual corneal surface by the laser beam emitted by the light source through the virtual projection lens when the virtual projection lens is in different positions; The position of the virtual projection lens when the radius of the light spot formed on the virtual corneal surface reaches its minimum value will be used as the position information of the virtual projection lens.

4. The corneal depth localization method as described in claim 2, characterized in that, The virtual optical element further includes a virtual detector, and the step of determining the position information of the virtual receiving lens within the second range includes: Within the second search range, the virtual receiving lens is controlled to move along the optical axis and rotate within a preset angle range; Record the radius of the laser beam reflected by the virtual cornea and formed on the surface of the virtual detector by the virtual receiving lens when the virtual receiving lens is in different positions and at different angles; The position of the virtual receiving lens is used as the position information of the virtual receiving lens when the radius of the light spot formed on the surface of the virtual detector is minimized and the object plane, the principal plane of the lens, and the image plane intersect on the same straight line.

5. The corneal depth localization method as described in claim 2, characterized in that, The step of determining the target corneal depth corresponding to the current spot position formed on the detector surface through the optical system includes: A laser beam is emitted onto the current corneal surface through a light source in the optical system; The position of the current spot formed on the detector surface by the receiving lens after the laser beam is reflected from the current corneal surface is obtained; Obtain the target mapping relationship, which is constructed based on the target optical simulation system and characterizes the correspondence between corneal depth and spot position; The target corneal depth corresponding to the current spot position is determined by the target mapping relationship.

6. The corneal depth localization method as described in claim 5, characterized in that, Before the step of obtaining the target mapping relationship, the method further includes: In the target optical simulation system, the virtual cornea is sequentially placed at positions corresponding to multiple preset depths; At each of the preset depths, the position of the light spot formed on the surface of the virtual detector by the virtual receiving lens after the laser beam of the virtual light source is reflected by the corneal surface; Based on the preset depths and corresponding spot positions, a target mapping relationship between corneal depth and spot position is constructed.

7. The corneal depth localization method as described in claim 5, characterized in that, The step of constructing a target mapping relationship between corneal depth and spot position based on each preset depth and the corresponding spot position includes: An initial mapping relationship between corneal depth and spot position is constructed based on each preset depth and the corresponding spot position; The initial spot position formed on the surface of the virtual detector when the virtual cornea is on a preset reference plane is obtained; The zero-point offset is determined based on the difference between the initial spot position and the preset spot position; The initial mapping relationship is corrected based on the zero-point offset to obtain the target mapping relationship.

8. A corneal depth positioning device, characterized in that, The device includes: The data receiving module is used to acquire an initial optical simulation system consisting of at least two virtual optical elements in response to initial parameters input by the user. The system simulation module is used to determine the position information of each virtual optical element in the initial optical simulation system based on the initial parameters, so as to obtain the target optical simulation system; The system construction module is used to construct an optical system based on the target optical simulation system, wherein the optical elements in the optical system correspond to each of the virtual optical elements, and the positions of each of the optical elements correspond to the corresponding virtual optical elements; The depth positioning module is used to determine the target corneal depth corresponding to the current spot position formed on the detector surface through the optical system.

9. A corneal depth positioning device, characterized in that, The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the corneal depth positioning method as described in any one of claims 1 to 7.

10. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, it implements the steps of the corneal depth positioning method as described in any one of claims 1 to 7.

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