Human eye measurement system

Abstract

The present disclosure provides a human eye measurement system, comprising: a beacon light source, configured to emit a primary light; a first collimated light conversion device, wherein the first collimated light conversion device converts the primary light into a collimated light; a first polarizing device, wherein the first polarizing device is configured to convert the collimated light into a polarized light; a first optical path adjustment component, wherein the first optical path adjustment component is configured to perform optical path adjustment on the polarized light to irradiate to a target human eye; a Hartmann wavefront sensor, wherein the Hartmann wavefront sensor is configured to receive reflected light from the retina of a target human eye in different diopter response states, so as to measure wavefront aberration information; a second polarizing device, wherein the a second polarizing device is located at the front end of the Hartmann wavefront sensor and configured to eliminate stray light; and a visual target display module, wherein the visual target display module comprises a visual target display, and the visual target display is configured to provide a fixation target during aberration measurement and a measurement target in visual function measurement.

Description

Human eye measurement system Technical Field

[0001] This disclosure relates to the technical fields of human eye wavefront aberration and human eye visual function measurement, and in particular to a human eye measurement system. Background Technology

[0002] Our understanding of wavefront aberrations in the human eye has progressed from low-order aberrations (myopia, hyperopia, astigmatism) to high-order aberrations (coma, cloverleaf aberration, spherical aberration, etc.). Low-order aberrations can be corrected using various mature methods such as eyeglasses, contact lenses, intraocular lenses, and laser surgery.

[0003] With small pupils, the values ​​of higher-order aberrations in the human eye are small and their impact on vision is negligible. However, in low-light conditions, as the pupil enlarges, the impact of higher-order aberrations on vision increases significantly. For example, glare from headlights while driving at night increases driving risk. Clinically, it has also been found that spherical aberration, a higher-order aberration, gradually increases with age. Therefore, for example, when choosing an intraocular lens for cataract surgery, more and more patients are opting for high-end spherical aberration lenses to reduce postoperative visual impairment. Accurately measuring higher-order aberrations and minimizing their impact on vision has become increasingly urgent.

[0004] Hartmann wavefront sensors are common wavefront aberration measurement devices for the human eye and are widely used in human eye aberration measurement. For example, patent documents CN110367924B, CN112754420A, and CN117357056A all use Hartmann wavefront sensors for wavefront aberration measurement.

[0005] Based on the principle of traditional Hartmann wavefront sensing measurement, pupil positioning error and stray light error in the measurement system are the main factors affecting measurement accuracy. Therefore, the first step in measurement is to align the human pupil with the Hartmann wavefront sensor. Generally, pupil alignment uses manual or automatic pupil detection and tracking techniques. However, due to hardware and software alignment errors and the physiological tremors of the subject, especially for subjects with small pupils, the Hartmann spot may deviate completely from the ideal center of the restoration matrix, leading to large measurement errors or even erroneous results. Furthermore, human eye measurement systems using Hartmann wavefront sensors are mostly transmissive optical structures, making it difficult to completely exclude back-reflected light from the measurement light path. Stray light entering the Hartmann wavefront sensor also significantly affects the measurement accuracy of human eye aberrations. Summary of the Invention

[0006] To address one of the aforementioned technical problems, this disclosure provides a human eye measurement system.

[0007] According to one aspect of this disclosure, a human eye measurement system is provided, comprising:

[0008] A beacon light source, which is used to emit initial light;

[0009] A first parallel light conversion device converts the initial light into parallel light;

[0010] A first polarization device, which converts the parallel light into polarized light;

[0011] A first optical path adjustment component adjusts the optical path of the polarized light to illuminate the target human eye;

[0012] A Hartmann wavefront sensor is used to receive retinal reflected light from the target human eye in different refractive response states to measure wavefront aberration information.

[0013] A second polarization device is located at the front end of the Hartmann wavefront sensor to eliminate stray light;

[0014] The target display module includes a target display, which is used to provide a fixed target for aberration measurement and a measurement target for visual function measurement.

[0015] According to at least one embodiment of the human eye measurement system of this disclosure, the second polarization device is disposed adjacent to the Hartmann wavefront sensor.

[0016] According to at least one embodiment of the human eye measurement system of this disclosure, the second polarization device is located between the Hartmann wavefront sensor and the aperture matching module.

[0017] The human eye measurement system according to at least one embodiment of the present disclosure further includes a refractive compensation module, wherein the light generated by the beacon light source is directly irradiated to the target human eye without passing through the refractive compensation module.

[0018] According to at least one embodiment of the human eye measurement system of the present disclosure, the target generated by the optotype display is imaged onto the target human eye after passing through the refractive compensation module, and the retinal reflected light from the target human eye in different refractive power response states is received by the Hartmann wavefront sensor through the refractive compensation module for wavefront aberration information measurement.

[0019] According to at least one embodiment of the human eye measurement system of this disclosure, the refractive compensation module is located between the first parallel light conversion device and the second parallel light conversion device.

[0020] According to at least one embodiment of the human eye measurement system of the present disclosure, the second optical path adjustment component is used to transmit light generated by the target display and to reflect light reflected by the target human eye to the Hartmann wavefront sensor via the second optical path adjustment component.

[0021] According to at least one embodiment of the human eye measurement system of this disclosure, the aperture matching module is disposed between the second optical path adjustment component and the second polarization device.

[0022] According to at least one embodiment of the human eye measurement system of the present disclosure, the target display module includes: a target imaging objective lens, the target imaging objective lens being located between the target display and the target human eye to facilitate the target human eye's observation of the fixed target or measurement target.

[0023] According to at least one embodiment of the human eye measurement system of the present disclosure, a focusing device is included between the target imaging objective and the target display, the focusing device adjusting the distance between the fixed target or measurement target provided by the target display and the target human eye by changing its position.

[0024] The human eye measurement system according to at least one embodiment of the present disclosure further includes:

[0025] The processing module is connected to the Hartmann wavefront sensor to receive the original Hartmann spot image of the target human eye acquired by the Hartmann wavefront sensor and to process the original Hartmann spot image of the target human eye.

[0026] According to at least one embodiment of the human eye measurement system of this disclosure, receiving a raw image of the Hartmann spot of a target human eye acquired by a Hartmann wavefront sensor, and processing the raw image of the Hartmann spot of the target human eye to obtain the wavefront aberration of the target human eye includes:

[0027] The original image of the Hartmann spot in the target human eye was obtained using a Hartmann wavefront sensor.

[0028] Adaptive thresholding is applied to the original Hartmann spot image to obtain the processed image.

[0029] The processed image is then subjected to connectivity processing to obtain the centroid of each Hartmann spot;

[0030] The center of the Hartmann spot in the original image of the entire target human eye is obtained based on all the centroids of the Hartmann spot.

[0031] The image center resetting amount is obtained based on the spot center of the original Hartmann image and the size of the original Hartmann image;

[0032] The original Hartmann spot image of the target human eye is translated according to the image center reset amount to obtain the final image, and the wavefront aberration of the target human eye is obtained from the final image.

[0033] According to at least one embodiment of the human eye measurement system of this disclosure, the processing module further obtains the refractive compensation amount of the target human eye based on the preliminary measurement result of the wavefront aberration of the target human eye; and controls the refractive compensation module according to the refractive compensation amount, so that the target human eye performs visual function measurement in a refractive correction state, and the final result of the wavefront aberration can also be obtained accordingly.

[0034] According to at least one embodiment of the human eye measurement system of this disclosure, the processing module is further configured to obtain the final result of the wavefront aberration of the target human eye under different refractive response states.

[0035] According to another aspect of this disclosure, a Hartmann spot image processing method is provided, comprising:

[0036] S102. Obtain the original image of the Hartmann spot of the target human eye based on the Hartmann wavefront sensor;

[0037] S104. Perform adaptive thresholding on the original Hartmann spot image to obtain the processed image;

[0038] S106. Perform connectivity processing on the processed image to obtain the centroid of each Hartmann spot;

[0039] S108. Obtain the center of the Hartmann spot in the original image of the entire target human eye based on all the centroids of the Hartmann spot;

[0040] S110. Obtain the image center reset amount based on the spot center of the original Hartmann image and the size of the original Hartmann image;

[0041] S112. The original image of the Hartmann spot of the target human eye is translated according to the image center reset amount to obtain the final image, and the wavefront aberration of the target human eye is obtained according to the final image.

[0042] The Hartmann spot image processing method according to at least one embodiment of the present disclosure is performed using the human eye measurement system described above.

[0043] According to at least one embodiment of the Hartmann spot image processing method of this disclosure, the centroid of the Hartmann spot can be obtained by the following formula:

[0044] Among them, (x i ,y iLet be the centroid of the i-th Hartmann spot, where i = 1…Q, Q is the total number of valid spots in the current image, L is the total number of pixels in the current Hartmann spot, and I…Q ... m x is the current pixel value. m y is the x-coordinate of the current pixel. m This represents the ordinate of the current pixel.

[0045] According to at least one embodiment of the Hartmann spot image processing method of this disclosure, the spot center of the original Hartmann spot image can be calculated by the following formula:

[0046] Where min is the minimum value function, (x c ,y c The center of all Hartmann spots is defined by the following formula:

[0047] According to at least one embodiment of the Hartmann spot image processing method of this disclosure, the image center reset amount is:

[0048] Where M is the image width of the original Hartmann spot image, and N is the image height of the original Hartmann spot image.

[0049] According to the Hartmann spot image processing method of at least one embodiment of this disclosure, the final image is obtained by the following formula:

[0050] Where Z(x,y) is the final image after correcting the center translation error.

[0051] In some embodiments of this disclosure, to obtain a practically usable human eye aberration measurement scheme, this disclosure employs a measurement algorithm based on post-matching alignment using Hartmann spot measurement, reducing the difficulty of pupil alignment. In some embodiments of this disclosure, techniques such as directly illuminating the human eye with a measurement light source and using a double polarizer structure to eliminate corneal reflection light are employed to eliminate stray light entering the Hartmann wavefront sensor, accurately measuring human eye wavefront aberrations and visual function. Attached Figure Description

[0052] The accompanying drawings illustrate exemplary embodiments of the present disclosure and, together with the description thereof, serve to explain the principles of the present disclosure. These drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification.

[0053] Figure 1 is a schematic block diagram of the structure of a human eye measurement system according to some embodiments of the present disclosure.

[0054] Figure 2 is a schematic block diagram of the structure of a binocular measurement system according to some embodiments of the present disclosure.

[0055] Figure 3 is a flowchart of a Hartmann spot image processing method according to some embodiments of the present disclosure.

[0056] Figures 4 and 5 are the original Hartmann spot image acquired by the Hartmann wavefront sensor of this disclosure and the image processed by the Hartmann spot image processing method, respectively.

[0057] Figure 6 is a flowchart of a human eye measurement method according to some embodiments of the present disclosure.

[0058] Figure Reference Numerals: 100 Human Eye Measurement System; 101 Beacon Light Source; 102 First Parallel Light Conversion Device; 103 First Polarizing Device; 104 First Optical Path Adjustment Assembly; 105 Hartmann Wavefront Sensor; 106 Second Polarizing Device; 107 Optical Target Display; 108 Aperture Matching Module; 109 Refractive Compensation Module; 110 Second Optical Path Adjustment Assembly; 111 Optical Target Imaging Objective; 112 Focusing Device; 113 Processing Module; 200 Target Human Eye Detailed Implementation

[0059] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present disclosure are shown in the accompanying drawings.

[0060] It should be noted that, where there is no conflict, the embodiments and features described in this disclosure can be combined with each other. The technical solutions of this disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0061] Unless otherwise stated, the exemplary implementations / embodiments shown are to be understood as providing exemplary features of various details that provide ways in which the technical concepts of this disclosure can be implemented in practice. Therefore, unless otherwise stated, the features of various implementations / embodiments may be additionally combined, separated, interchanged and / or rearranged without departing from the technical concepts of this disclosure.

[0062] The use of crosshairs and / or shading in the accompanying drawings is generally used to clarify the boundaries between adjacent components. Thus, unless otherwise stated, the presence or absence of crosshairs or shading does not convey or indicate any preference or requirement for the specific material, material properties, dimensions, proportions, commonalities between the illustrated components, or any other characteristics, properties, etc., of the components. Furthermore, in the accompanying drawings, the dimensions and relative dimensions of components may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a specific process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, the same reference numerals denote the same components.

[0063] When a component is referred to as being "on" or "above" another component, "connected to," or "joined to" another component, the component may be directly on, directly connected to, or directly joined to the other component, or there may be intermediate components. However, when a component is referred to as being "directly on" another component, "directly connected to," or "directly joined to" another component, there are no intermediate components. Therefore, the term "connection" can refer to a physical connection, an electrical connection, etc., and may or may not have intermediate components.

[0064] For descriptive purposes, this disclosure may use spatial relative terms such as “below,” “under,” “below,” “down,” “above,” “above,” “higher,” and “side (e.g., in a “sidewall”)” to describe the relationship between one component and another component as shown in the accompanying drawings. In addition to the orientations depicted in the drawings, the spatial relative terms are also intended to encompass different orientations of the device during use, operation, and / or manufacture. For example, if the device in the drawings is flipped, a component described as “below” or “under” another component or feature would subsequently be positioned “above” said other component or feature. Thus, the exemplary term “below” can encompass both “above” and “below” orientations. Furthermore, the device may be otherwise positioned (e.g., rotated 90 degrees or in other orientations), thus interpreting the spatial relative descriptive terms used herein accordingly.

[0065] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “the” are intended to include the plural forms as well. Furthermore, when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, integrals, steps, operations, parts, components, and / or groups thereof, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, parts, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, thus explaining the inherent biases in measurements, calculated values, and / or provided values ​​that would be recognized by one of ordinary skill in the art.

[0066] Figure 1 is a schematic block diagram of the structure of a human eye measurement system 100 according to some embodiments of the present disclosure.

[0067] As shown in Figure 1, this disclosure provides a human eye measurement system 100, comprising:

[0068] Beacon light source 101, beacon light source 101 is used to emit initial light;

[0069] The first parallel light conversion device 102 converts the initial light into parallel light;

[0070] The first polarization device 103 converts parallel light into polarized light.

[0071] The first optical path adjustment component 104 adjusts the optical path of polarized light to illuminate the target human eye 200.

[0072] Hartmann wavefront sensor 105 is used to receive retinal reflected light from a target human eye 200 in different refractive response states for wavefront aberration information measurement.

[0073] The second polarization device 106 is located at the front end of the Hartmann wavefront sensor 105 to eliminate stray light.

[0074] The target display module includes a target display 107 for providing a fixed target during aberration measurement and a measurement target during visual function measurement.

[0075] The light source type of the beacon light source 101 can be LD light source, LED light source, SLD light source, etc., and the shape of the light source can be a point light source or an extended light source, etc.

[0076] In some embodiments, as shown in FIG1, the second polarization device 106 is disposed adjacent to the Hartmann wavefront sensor 105. That is, the second polarization device 106 of this disclosure can be located between the aperture matching module 108 and the Hartmann wavefront sensor 105, thereby allowing light rays to directly enter the Hartmann wavefront sensor 105 via the second polarization device 106.

[0077] In some embodiments, the human eye measurement system 100 of this disclosure further includes a refractive compensation module 109, which is disposed in front of the target human eye 200 to perform refractive compensation when the target human eye 200 observes the target image provided by the target display 107, wherein the light generated by the beacon light source 101 directly illuminates the target human eye 200 without passing through the refractive compensation module 109.

[0078] In other words, unlike existing technologies, the refractive compensation module 109 of this application is disposed between the first optical path adjustment component 104 and the second optical path adjustment component 110. The second optical path adjustment component 110 is used to transmit the light generated by the target display 107 and to reflect the light reflected by the target eye 200 to the Hartmann wavefront sensor 105 via the second optical path adjustment component 110. More specifically, the light emitted by the target display 107 is imaged onto the target eye 200 via the focusing device 112, the target imaging objective lens 111, the second optical path adjustment component 110, the refractive compensation module 109, and the first optical path adjustment component 104. The beacon light reflected by the target eye enters the Hartmann wavefront sensor 105 after being transmitted through the first optical path adjustment component 104, reflected by the refractive compensation module 109, and reflected by the second optical path adjustment component 110.

[0079] In some embodiments, the refractive compensation module includes a transmissive / reflective 4f system combined with a cylindrical lens group, a liquid lens, a flexible zoom lens, a deformable mirror, or a liquid crystal spatial light modulator.

[0080] Therefore, the polarized light generated by the first polarization device 103 of this disclosure does not pass through the refractive compensation module 109. Moreover, since the beacon light generated by the beacon light source directly illuminates the human eye, the influence of the back reflection light of the beacon light source on the wavefront aberration measurement can be effectively eliminated.

[0081] Furthermore, the target generated by the visual target display 107 is imaged onto the target human eye 200 after passing through the refractive compensation module 109, and the retinal reflected light from the target human eye 200 in different refractive response states is received by the Hartmann wavefront sensor 105 through the refractive compensation module 109 to perform wavefront aberration information measurement.

[0082] Referring again to Figures 1 and 2, in some embodiments of this disclosure, the human eye measurement system 100 further includes a target imaging objective 111, which is located between the target display 107 and the target eye 200 to facilitate the target eye 200's observation of the fixation target or measurement target. In a preferred embodiment, the target imaging objective 111 may be a convex lens or a combination of convex lenses, etc.

[0083] Preferably, the target imaging objective lens 111 of this disclosure is located outside the optical path of the beacon light source 101 and the target human eye 200, and also outside the optical path of the Hartmann wavefront sensor 105 and the target human eye 200, so as to avoid unnecessary influence on the measurement of wavefront aberration information.

[0084] Referring to FIG2, in some other embodiments of the present disclosure, the human eye measurement system 100 of the present disclosure includes: a focusing device 112, which adjusts the distance between the fixed target or measurement target provided by the visual target display 107 and the target human eye 200 by changing its position; wherein the focusing device 112 includes a monolithic lens, a transmissive / reflective lens group or a variable focus liquid lens, etc.

[0085] This disclosure adjusts the distance between the fixed target or measurement target provided by the visual target display 107 and the target human eye 200, so that the target human eye 200 produces different refractive power responses when observing the fixed target or measurement target, thereby enabling the Hartmann wavefront sensor 105 to measure wavefront aberration information of the target human eye 200 under different refractive power response states.

[0086] When the human eye measurement system 100 of this disclosure is in use, after the pupil of the target human eye 200 is aligned with the main optical path of the human eye measurement system 100, the target human eye observes the target on the optotype display for fixation. The light emitted by the beacon light source is collimated into parallel light by the first parallel light conversion device, and then reflected by the first polarization device and the first optical path adjustment component into the target human eye, where it is imaged on the retina by the target human eye refractive system.

[0087] Back-reflected light on the retina carries human eye aberration information back along the original optical path to the second optical path adjustment component. After being reflected by the second optical path adjustment component, it passes through the aperture matching module and the second polarization device in sequence before entering the Hartmann wavefront sensor. The second polarization device is used to eliminate back-reflected stray light in the system, reducing the difficulty of subsequent image processing. At this time, the Hartmann wavefront sensor will be able to obtain the original image of the Hartmann spot of the target human eye. After the original image of the Hartmann spot of the target human eye is processed by the processing module 113 (e.g., a computer), the wavefront aberration of the target human eye 200 can be obtained. Accordingly, the wavefront aberration is the preliminary measurement result.

[0088] Then, based on the preliminary measurement results of wavefront aberration, the refractive compensation module is driven to perform defocus and astigmatism compensation. Through the linkage between the beacon light source and the refractive compensation module, the beacon light source is pre-compensated at the same time. In this way, when the target human eye has refractive power, the beacon light source can still be imaged on the retina by the human eye's refractive system.

[0089] After at least two measurement iterations, refractive compensation of the target human eye is completed, and then the final measurement of wavefront aberration of the human eye is performed. The Hartmann wavefront sensor collects the reflected light spot of the human eye at this time (i.e., obtains the original image of the Hartmann light spot of the target human eye). The processing module 113 performs light spot preprocessing based on the collected original image of the Hartmann light spot and uses the image to obtain the final image after correcting the center translation error, thus completing the measurement of wavefront aberration of the target human eye.

[0090] Specifically, the processing module 113 (computer) of this disclosure is connected to the Hartmann wavefront sensor 105 to receive the original Hartmann spot image of the target human eye 200 acquired by the Hartmann wavefront sensor 105, and to process the original Hartmann spot image of the target human eye 200 to obtain the wavefront aberration of the target human eye 200.

[0091] Specifically, the system receives the original Hartmann spot image of the target eye 200 acquired by the Hartmann wavefront sensor 105, processes the original Hartmann spot image of the target eye 200, and obtains the wavefront aberration of the target eye 200. This includes:

[0092] S102. Obtain the original image of the Hartmann spot of the target human eye 200 based on the Hartmann wavefront sensor 105;

[0093] S104. Perform adaptive thresholding on the original Hartmann spot image to obtain the processed image;

[0094] S106. Perform connectivity processing on the processed image to obtain the centroid of each Hartmann spot;

[0095] S108. Obtain the center of the Hartmann spot in the original image of the entire target human eye based on all the centroids of the Hartmann spot;

[0096] S110. Obtain the image center reset amount based on the spot center of the original Hartmann image and the size of the original Hartmann image;

[0097] S112. The original image of the Hartmann spot of the target human eye 200 is translated according to the image center reset amount to obtain the final image, and the wavefront aberration of the target human eye 200 is obtained according to the final image.

[0098] Therefore, the human eye measurement system 100 of this disclosure can improve the measurement accuracy of wavefront aberrations.

[0099] In other words, the processing module 113 of the human eye measurement system 100 of this disclosure also obtains the refractive compensation amount of the target human eye 200 based on the preliminary measurement result of the wavefront aberration of the target human eye 200; and controls the refractive compensation module 109 based on the refractive compensation amount, so that the target human eye 200 performs visual function measurement in the refractive correction state, and obtains the final result of the wavefront aberration of the target human eye. Thus, the human eye measurement system 100 of this disclosure obtains the refractive compensation amount based on the first detected wavefront aberration (i.e. the preliminary measurement result of the wavefront aberration) and obtains the final result of the wavefront aberration of the target human eye accordingly. Combined with the center reset processing algorithm, the measurement accuracy of the wavefront aberration of the target human eye is improved.

[0100] The processing module 113 is also used to obtain the final result of the wavefront aberration of the target human eye 200 under different refractive power response states.

[0101] Figure 2 is a schematic block diagram of the structure of a binocular measurement system according to some embodiments of the present disclosure.

[0102] As shown in Figure 2, the binocular measurement system of this disclosure may include two of the above-mentioned human eye measurement systems, and the two eye measurement systems are symmetrically arranged to enable binocular measurement. Thus, the binocular measurement system of this disclosure can simultaneously measure both eyes of a person. Those skilled in the art should understand that the binocular measurement system of this disclosure only needs to include one processing module; that is, the two eye measurement systems perform information processing and control based on the same computer device.

[0103] Figure 3 is a flowchart of a Hartmann spot image processing method according to some embodiments of the present disclosure.

[0104] As shown in Figure 3, this disclosure provides a Hartmann spot image processing method, which may include:

[0105] S102. Obtain the original image of the Hartmann spot of the target human eye 200 based on the Hartmann wavefront sensor 105;

[0106] S104. Perform adaptive thresholding on the original Hartmann spot image to obtain the processed image;

[0107] S106. Perform connectivity processing on the processed image to obtain the centroid of each Hartmann spot;

[0108] S108. Obtain the center of the Hartmann spot in the original image of the entire target human eye based on all the centroids of the Hartmann spot;

[0109] S110. Obtain the image center reset amount based on the spot center of the original Hartmann image and the size of the original Hartmann image;

[0110] S112. The original image of the Hartmann spot of the target human eye 200 is translated according to the image center reset amount to obtain the final image, and the wavefront aberration of the target human eye 200 is obtained according to the final image.

[0111] In other words, the processing module of this disclosure can execute the Hartmann spot image processing method and obtain the corresponding results.

[0112] The Hartmann spot image processing method will be described in detail below. Those skilled in the art should know that this processing module can also perform the detailed steps of the Hartmann spot image processing method described below.

[0113] In S102, the original Hartmann spot image is shown in Figure 4. There is a significant center offset between the spot center and the optical axis of the measurement optical path in this original Hartmann spot image. If this image is directly used for human eye aberration restoration, the restored aberration will differ significantly from the true aberration, severely affecting the accuracy of aberration measurement. Therefore, the Hartmann spot image processing method disclosed in this invention can recenter the original Hartmann spot image. The original Hartmann spot image obtained in S102 is I(x,y), where (x,y) is the coordinate position, and the image size is M×N.

[0114] In some embodiments, the processed image in S104 can be defined as B(x,y).

[0115] Preferably, in S106, the centroid of the Hartmann spot can be obtained by the following formula:

[0116] Among them, (x i ,y i Let be the centroid of the i-th Hartmann spot, where i = 1…Q, Q is the total number of valid spots in the current image, L is the total number of pixels in the current Hartmann spot, and I…Q ... m x is the current pixel value. m y is the x-coordinate of the current pixel. m This represents the ordinate of the current pixel.

[0117] In S108, the center of the Hartmann spot in the original image can be calculated using the following formula:

[0118] Where min is the minimum value function, (x c ,y c ( ) represents the center of all Hartmann spots, which can be calculated using the following formula:

[0119] In some embodiments, the image center reset amount in S110 is:

[0120] Where M is the image width of the original Hartmann spot image, and N is the image height of the original Hartmann spot image.

[0121] In S112, the final image can be obtained by the following formula:

[0122] Z(x,y) is the final image after correcting the center translation error, and this image is used to calculate human eye aberrations. The final image is shown in Figure 5. It can be seen that the center shift in the original image of the Hartmann spot has been effectively removed.

[0123] Therefore, the human eye measurement system of this disclosure can calculate defocus, astigmatism, and astigmatic axis based on the measured wavefront aberration information, and the computer-controlled refractive compensation module can complete the correction of the corresponding refractive errors. Thus, the objective aberration measurement and refractive error correction of a single eye are completed. Accommodation response measurement and various visual function measurements can then be performed.

[0124] When in use, the human eye measurement system disclosed herein can achieve the following:

[0125] I. Measurement of aberrations under different accommodation states:

[0126] After objective aberration measurement and refractive error correction are completed, the computer-controlled focusing device moves to different positions in front of the measuring eye to generate different refractive power stimuli. The Hartmann wavefront sensor measures the aberration of the human eye at this time, which can complete the aberration measurement under different accommodation states and obtain the accommodation response of the human eye.

[0127] II. Visual acuity measurement shall include at least 6 measurement states:

[0128] The computer-controlled focusing device moves the optotype display to a position 30cm in front of the measuring eye. Wavefront aberration measurement and refractive error correction are performed for the left and right eyes respectively at the current position. The computer-controlled optotype display completes the test tasks of measuring the near vision of the left eye and the near vision of the right eye respectively.

[0129] The computer-controlled focusing device moves the optotype display to a position 60cm in front of the measuring eye. Wavefront aberration measurement and refractive error correction are performed for the left and right eyes respectively at the current position. The computer-controlled optotype display completes the intermediate visual acuity measurement for the left eye and the intermediate visual acuity measurement for the right eye respectively.

[0130] The computer-controlled focusing device moves the optotype display to a position 500cm in front of the measuring eye. Wavefront aberration measurement and refractive error correction are performed for the left and right eyes respectively at the current position. The computer-controlled optotype display completes the test tasks of measuring the distance visual acuity of the left eye and the right eye respectively.

[0131] III. The comparison sensitivity measurement should include at least two measurement states, each completed according to the following steps:

[0132] The computer-controlled focusing device moves the optotype display to a position 500cm in front of the measuring eye. At this position, wavefront aberration measurement and refractive error correction of the left eye are performed. The computer controls the left optotype display to randomly generate grating stripes with different spatial frequencies and contrast values ​​according to the contrast sensitivity measurement method. The test subject answers whether he / she can recognize them subjectively, and the contrast sensitivity measurement result of the left eye is obtained.

[0133] The computer-controlled focusing device moves the optotype display to a position 500cm in front of the measuring eye. Wavefront aberration measurement and refractive error correction of the right eye are performed at the current position. The computer controls the right optotype display to randomly generate grating stripes with different spatial frequencies and contrast values ​​according to the contrast sensitivity measurement method. The test subject answers based on whether he or she can recognize them, and the contrast sensitivity measurement result of the right eye is obtained.

[0134] The computer-controlled focusing device moves the target display to different positions in front of the measuring eye, and can also perform contrast sensitivity measurements under different adjustment states.

[0135] When using the binocular measurement system disclosed herein, the optical paths for the left and right eyes are symmetrically set, and the layout of each individual optical path is the same as or similar to that of the human eye measurement system. When using the binocular measurement system, the eyes are aligned first. After alignment, the eyes simultaneously observe the same target displayed on the optotype display of the two optical paths for fixation. Wavefront aberration is measured synchronously by both eyes. The measurement process is the same as or similar to that of the human eye measurement system, and will not be described in detail here.

[0136] When performing simultaneous binocular measurements, aligning the pupils and the center of the binocular measurement system is more difficult than with a monocular system. Therefore, the final wavefront aberration measurement process, in which the computer performs spot preprocessing on the acquired Hartmann spot image, is more important for obtaining accurate wavefront aberration measurement results.

[0137] Based on the measured wavefront aberration information, defocus, astigmatism, and astigmatic axis can be calculated. The computer-controlled refractive compensation module can then correct the corresponding refractive errors. This completes the binocular objective aberration measurement and refractive error correction. Then, binocular accommodation response measurement and various visual function measurements can be performed.

[0138] When using the binocular measurement system disclosed herein, binocular alignment is first completed. Then, the computer controls the left and right optotype displays to show the same test task. The computer controls the focusing device to move the optotype displays to 30mm, 60mm and 500cm in front of the measuring eyes, respectively. Wavefront aberration measurement and refractive error correction are performed for the left and right eyes at the current positions. The measurement of binocular near vision, binocular intermediate vision and binocular distance vision is completed under binocular fusion conditions.

[0139] The computer-controlled focusing device moves the optotype display to a position 500cm in front of the measuring eye. First, binocular alignment is completed. At the current position, wavefront aberration measurement and refractive error correction are performed on both eyes. Then, the computer controls the left and right optotype displays to display the same target, that is, randomly displaying grating stripes with different spatial frequencies and different contrast values. The test subject answers based on whether he or she can recognize the target, and the contrast sensitivity measurement results of both eyes are obtained.

[0140] Based on the above technical content, the technical solution disclosed herein has the following advantages compared with the prior art:

[0141] (1) This disclosure can effectively eliminate the influence of the back-reflected light from the beacon light source on wavefront aberration measurement;

[0142] (2) The Hartmann spot image processing method based on image center resetting of the present invention does not require additional hardware modifications and optical path design of the system. It reduces the difficulty of pupil alignment while obtaining accurate wavefront aberration measurement results, without increasing the cost and complexity of the system, and is easy to integrate into the system.

[0143] (3) Based on accurate wavefront aberration measurement and corrected visual function measurement, human visual function indicators can be obtained more conveniently and accurately.

[0144] Figure 6 is a flowchart of a human eye measurement method according to some embodiments of the present disclosure.

[0145] As shown in Figure 6, this disclosure provides a human eye measurement method, which can measure the wavefront aberration of the human eye using the human eye measurement system or binocular measurement system provided in this disclosure. The human eye measurement method includes:

[0146] S1. Perform monocular or binocular wavefront aberration measurements to obtain preliminary wavefront aberration measurement results;

[0147] S2. Calculate the refractive compensation amount for monocular or binocular vision based on the preliminary measurement results of wavefront aberration;

[0148] S3. Control the refractive compensation module to enable visual function measurement in monocular or binocular refractive correction state;

[0149] S4. To measure wavefront aberrations by placing the monocular or binocular eyes in different refractive response states, thereby obtaining the wavefront aberrations of the target human eye.

[0150] In the description of this specification, the references to terms such as "one embodiment / mode," "some embodiments / modes," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment / mode or example is included in at least one embodiment / mode or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment / mode or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments / modes or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments / modes or examples described in this specification, as well as the features of different embodiments / modes or examples.

[0151] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0152] Those skilled in the art should understand that the above embodiments are merely for illustrating the present disclosure and are not intended to limit the scope of the disclosure. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of the present disclosure.

Claims

1. A human eye measurement system, characterized in that, include: A beacon light source, which is used to emit initial light; A first parallel light conversion device converts the initial light into parallel light; A first polarization device, which converts the parallel light into polarized light; A first optical path adjustment component adjusts the optical path of the polarized light to illuminate the target human eye; A Hartmann wavefront sensor is used to receive retinal reflected light from the target human eye in different refractive response states to measure wavefront aberration information. A second polarization device is located at the front end of the Hartmann wavefront sensor to eliminate stray light; A target display module, comprising a target display, which provides a fixation target for aberration measurement and a measurement target for visual function measurement. A refractive compensation module is provided, in which the light generated by the beacon light source directly illuminates the target eye without passing through the refractive compensation module; as well as The processing module is connected to the Hartmann wavefront sensor to receive the original Hartmann spot image of the target human eye acquired by the Hartmann wavefront sensor, and to process the original Hartmann spot image of the target human eye to obtain the wavefront aberration of the target human eye. Specifically, it receives the original Hartmann spot image of the target human eye acquired by a Hartmann wavefront sensor, and processes the original Hartmann spot image of the target human eye to obtain the wavefront aberration of the target human eye, including: The original image of the Hartmann spot in the target human eye was obtained using a Hartmann wavefront sensor. Adaptive thresholding is applied to the original Hartmann spot image to obtain the processed image. The processed image is then subjected to connectivity processing to obtain the centroid of each Hartmann spot; The center of the Hartmann spot in the original image of the entire target human eye is obtained based on all the centroids of the Hartmann spot. The image center resetting amount is obtained based on the spot center of the original Hartmann image and the size of the original Hartmann image; The original Hartmann spot image of the target human eye is translated according to the image center reset amount to obtain the final image, and the wavefront aberration of the target human eye is obtained from the final image.

2. The human eye measurement system according to claim 1, characterized in that, The second polarization device is positioned immediately adjacent to the Hartmann wavefront sensor.

3. The human eye measurement system according to claim 1, characterized in that, The target generated by the visual target display is imaged onto the target human eye after passing through the refractive compensation module, and the retinal reflected light from the target human eye in different refractive power response states is received by the Hartmann wavefront sensor through the refractive compensation module to perform wavefront aberration information measurement.

4. The human eye measurement system according to claim 1, characterized in that, The target display module includes a target imaging objective lens, which is located between the target display and the target human eye to facilitate the target human eye's observation of the fixed target or measurement target.

5. The human eye measurement system according to claim 4, characterized in that, The target imaging objective lens and the target display include a focusing device that adjusts the distance between the fixed target or measurement target provided by the target display and the target's human eye by changing its position.

6. The human eye measurement system according to claim 1, characterized in that, The processing module also obtains the refractive compensation amount of the target eye based on the preliminary measurement results of the wavefront aberration of the target eye; and controls the refractive compensation module based on the refractive compensation amount, so that the target eye performs visual function measurement in the refractive correction state.

7. The human eye measurement system according to claim 6, characterized in that, The processing module is also used to obtain the final result of the wavefront aberration of the target human eye under different refractive power response states.

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