System and method for optical detection of the eye

Abstract

The present disclosure provides a system for optical detection of an eye, comprising: a light emitting assembly configured to form an incident light ray array comprising a plurality of incident light rays parallel to a chief ray; a half mirror configured to reflect the incident light ray array at an angle to an optical axis of the system for forming a plurality of chief rays parallel to the optical axis of the system; a first objective lens having an optical axis coinciding with the optical axis of the system for converging the plurality of chief rays formed via the half mirror reflection onto a pupil plane of a measured eye so as to form a spot array on a retina of the measured eye; and a photodetector configured to acquire a spot array image corresponding to the spot array for detecting optical performance of the retina of the measured eye. The present disclosure can simultaneously measure optical imaging quality of a central field of view of the retina along an optical axis direction and optical imaging quality of a peripheral field of view of the retina to achieve fast detection of optical quality of the eye for a wide field of view on and off the optical axis.

Description

Technical Field

[0001] The embodiments of this disclosure generally relate to the field of optical inspection, and more specifically, to a system and method for optical inspection of the eye. Background Technology

[0002] Traditional systems for ocular optical testing can only measure the optical imaging quality of the central retinal field of view along the visual axis, and cannot be directly used to measure the optical imaging quality of the peripheral retinal field of view. For example, in clinical practice, a binocular open-field infrared autorefractor combined with a self-made curved optotype is commonly used to measure peripheral retinal refractive errors at different eccentric angles. However, this method is time-consuming, requires the subject to cooperate in adjusting their gaze direction, and has a limited number of peripheral retinal refractive sites that can be measured. Wavefront aberrometers using wavefront aberration technology are also frequently used to measure peripheral retinal refractive errors, but traditional wavefront aberrometers can only measure the refractive state of a single retinal site. Different peripheral retinal refractive errors at different eccentric angles must be obtained through manual point-by-point measurements, thus also requiring a high degree of subject cooperation and consuming a significant amount of time.

[0003] In summary, the shortcomings of the traditional systems used for ocular optical testing are that they cannot directly and efficiently measure the optical imaging quality of the entire peripheral field of vision of the retina, require a high degree of cooperation from the subject, and are time-consuming. Summary of the Invention

[0004] This disclosure provides a system and method for optical inspection of the eye, which can directly and efficiently measure the optical imaging quality of the entire peripheral field of view of the retina.

[0005] According to a first aspect of this disclosure, a system for optical detection of the eye is provided. The system includes: a light-emitting component configured to form an array of incident rays including multiple incident rays parallel to a principal ray; a semi-reflective mirror whose reflective surface is configured at an angle to the optical axis of the system for reflecting the array of incident rays to form multiple principal rays parallel to the optical axis of the system; a first objective lens whose axis coincides with the optical axis of the system for converging the multiple principal rays formed by reflection via the semi-reflective mirror onto the pupillary surface of the eye being tested, so as to form a light spot array on the retina of the eye being tested; and a photodetector configured to acquire an image of the light spot array corresponding to the light spot array for detecting the optical performance of the retina of the eye being tested.

[0006] In some embodiments, the multiple incident rays included in the incident ray array have the same light intensity. And in some embodiments, the light-emitting component includes: a light-emitting device for forming a point light source array; and a light-transmitting device having a light-transmitting aperture array for allowing the point light source array to form an incident ray array via the light-transmitting aperture array.

[0007] In some embodiments, the light-emitting device includes a coaxially arranged light source, a first lens, a diffusion plate, and a pinhole array, wherein the light emitted by the light source passes sequentially through the first lens, the diffusion plate, and the pinhole array to form a point light source array.

[0008] In some embodiments, the aperture array of the light-transmitting device is configured to limit the diameter of the incident light rays included in the incident light ray array formed by the light-emitting component.

[0009] In some embodiments, the arrangement of the light-transmitting aperture array corresponds to the arrangement of the formed point light source array.

[0010] In some embodiments, the formed point light source array is located on the front focal plane of the first objective lens, and the pupil plane of the tested eyeball is located on the rear focal plane of the first objective lens.

[0011] In some embodiments, the device further includes a second objective lens, an aperture, and a second lens that are sequentially and coaxially positioned relative to the photodetector, and the second lens is confocal with the first objective lens.

[0012] In some embodiments, the light spot array formed on the retina of the eye being tested is detected by a photodetector in sequence via the pupillary surface of the eye being tested, the first objective lens, the semi-reflective lens, the second lens, the aperture stop, and the second objective lens, and a light spot array image corresponding to the light spot array is formed on the photodetector.

[0013] In some embodiments, the device further includes a defocus compensation unit disposed between the light-emitting component and the first objective lens, wherein the defocus compensation unit includes a first prism and a second prism disposed along a direction perpendicular to the optical axis, and the distance between the first prism and the second prism is adjustable to form a focused light spot array on the retina of the eye being tested.

[0014] According to a second aspect of this disclosure, a method for obtaining the wavefront aberration of a tested eye using the system of the first aspect of this disclosure is also provided. The method includes: obtaining a two-dimensional dot spread function (DFS) of a spot image in a spot array formed on a photodetector, the DFS corresponding to a spot in a spot array formed on the retina of the tested eye and its corresponding field of view; and performing inverse fitting of the DFS to obtain the wavefront aberration of the tested eye.

[0015] In some embodiments, backfitting the two-dimensional point spread function to obtain the wavefront aberration of the tested eye includes: calculating the pupil function based on the wavefront aberration polynomial of the current coefficients; calculating the point spread function based on the pupil function; comparing the calculated point spread function with the two-dimensional point spread function for each corresponding retinal region of the field of view to determine whether the relationship between the calculated point spread function and the two-dimensional point spread function satisfies a threshold condition; and outputting the wavefront aberration polynomial of the current coefficients as the wavefront aberration of the tested eye in response to the relationship between the calculated point spread function and the two-dimensional point spread function satisfying the threshold condition.

[0016] In some embodiments, the method for obtaining the wavefront aberration of the tested eyeball further includes: in response to the relationship between the calculated point spread function and the two-dimensional point spread function not satisfying a threshold condition, adjusting the current coefficients of the wavefront aberration polynomial, and recalculating the pupil function and the point spread function based on the adjusted coefficients of the wavefront aberration polynomial, until the relationship between the recalculated point spread function and the two-dimensional point spread function satisfies the threshold condition.

[0017] It should also be understood that the description in the Summary of the Invention is not intended to limit the key or essential features of the embodiments of this disclosure, nor is it intended to restrict the scope of this disclosure. Other features of the embodiments of this disclosure will become readily apparent from the following description. Attached Figure Description

[0018] The above and other objects, features, and advantages of embodiments of the present disclosure will become more readily understood from the following detailed description with reference to the accompanying drawings. In the drawings, various embodiments of the present disclosure will be described by way of example and non-limiting means. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0019] Figure 1 A schematic diagram of a system for optical detection of the eye according to an embodiment of the present disclosure is shown.

[0020] Figure 2 An exemplary schematic diagram of a light-emitting component according to an embodiment of the present disclosure is shown.

[0021] Figure 3A A schematic diagram is shown of a point light source array formed by light-emitting devices according to an embodiment of the present disclosure.

[0022] Figure 3B A schematic diagram is shown illustrating a point light source array formed by an array of light-emitting end faces of a multimode fiber bundle according to an embodiment of the present disclosure.

[0023] Figure 4A A schematic diagram of a ring-shaped array of point light sources according to an embodiment of the present disclosure is shown.

[0024] Figure 4B A schematic diagram of a point light source array arranged in a grid pattern according to an embodiment of the present disclosure is shown.

[0025] Figure 5A A schematic diagram of a light-transmitting device with a ring-shaped array of light-transmitting apertures according to an embodiment of the present disclosure is shown.

[0026] Figure 5B A schematic diagram of a light-transmitting device with a light-transmitting aperture array arranged in a grid pattern according to an embodiment of the present disclosure is shown.

[0027] Figure 6 A schematic diagram of a defocus compensation unit according to an embodiment of the present disclosure is shown.

[0028] Figure 7 A flowchart is shown of a method for obtaining wavefront aberrations of a tested eyeball according to an embodiment of the present disclosure.

[0029] Figure 8 A flowchart is shown of a method for inversely fitting a two-dimensional point spread function to obtain the wavefront aberration of the tested eyeball according to an embodiment of the present disclosure.

[0030] Figure 9 A block diagram schematically illustrates a computing device suitable for implementing embodiments of the present disclosure. Detailed Implementation

[0031] Preferred embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0032] The term "comprising" and its variations as used herein signify open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "at least partially based on". The terms "one example embodiment" and "one embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc., may refer to different or the same objects.

[0033] As described above, traditional systems for eye optical testing can only measure the optical imaging quality of the central field of vision along the visual axis. They cannot be used directly and efficiently to measure the optical imaging quality of multiple sites on the retina or the entire peripheral field of vision. Furthermore, they require a high degree of cooperation from the subject and are time-consuming.

[0034] To at least partially address one or more of the aforementioned problems and other potential issues, exemplary embodiments of this disclosure provide a system for optical detection of the eye. This system comprises a light-emitting component for forming an array of incident rays including multiple incident rays parallel to the principal rays; a semi-reflective mirror with its reflective surface at an angle to the optical axis of the system for reflecting the array of incident rays into multiple principal rays parallel to the optical axis; and a first objective lens for converging the multiple principal rays onto the pupillary surface of the eye being tested to form a light spot array on the retina. This disclosure can utilize the multiple principal rays to form a light spot array on the retina corresponding to the central field of view and multiple peripheral refractive points at different angles. Furthermore, the system of this disclosure also acquires a spot array image corresponding to the spot array through a photodetector for detecting the optical performance of the retina of the tested eye. This disclosure can determine the optical performance of the retina based on the spot array image, which indicates the refractive state of the central field of view and the peripheral field of view of the retina. Therefore, the system for ocular optical detection provided by this disclosure can not only measure the optical imaging quality of the central field of view of the retina along the visual axis, but also directly and efficiently measure the optical imaging quality of the peripheral field of view of the retina, thereby achieving rapid detection of the eye's optical quality in both the on-axis and off-axis wide field of view. Furthermore, the system of this disclosure has a simple structure, low cost, and is easy to use, possessing significant commercial potential.

[0035] Figure 1 A schematic diagram of a system 100 for ocular optical detection according to an embodiment of the present disclosure is shown. This system 100 can be used to detect, for example, the optical performance of the central and peripheral fields of view of the retina of a tested eye 190. Figure 1 As shown, system 100 includes, for example, at least: a light-emitting component 110, a semi-reflective mirror 120, a first objective lens 130, and a photodetector 140.

[0036] The light-emitting component 110 is configured to form an incident light array. The incident light array, for example, includes multiple incident light beams parallel to the main light beam. In some embodiments, the light-emitting component 110 may include multiple devices to form an incident light array including multiple parallel incident light beams. The following will be combined with... Figures 2-5B Examples of light-emitting components that can be used in embodiments of this disclosure are described in further detail.

[0037] Figure 2 An exemplary schematic diagram of a light-emitting component 210 according to an embodiment of the present disclosure is shown. Figure 2 As shown, the light-emitting component 210 may include a light-emitting device 212 and a light-transmitting device 214. The point light source array formed by the light-emitting device 212 forms an incident light array via the light-transmitting device 214.

[0038] The light-emitting device 212 is used to form a point light source array, for example, by emitting an array of illumination beams. The formed point light source array is, for example, but not limited to, a light source array formed by an array of light-emitting end faces of an optical fiber bundle, a light source array formed by an LED array, or a light source array formed by illuminating an array of through holes (e.g., a pinhole array) with light-emitting sources. Figure 3A and Figure 3B Different implementations of point light source arrays are shown.

[0039] Figure 3A A schematic diagram is shown of a point light source array formed by light-emitting devices 310. (See diagram for example.) Figure 3A As shown, the light-emitting device 310 may include a coaxially arranged light source 312, a first lens 314, a diffusion plate 316, and a pinhole array 318. In some embodiments, the light emitted by the light source 312 passes sequentially through the first lens 314, the diffusion plate 316, and the pinhole array 318 to form a point light source array. For example, the light emitted by the light source 312 is collimated and expanded by the first lens 314 to form a collimated beam, which then illuminates the diffusion plate 316 to form a beam with uniform light intensity distribution, and this beam further illuminates the pinhole array 318 to form a point light source array.

[0040] Figure 3B A schematic diagram is shown illustrating a point light source array formed by an array of light-emitting end faces of a multimode fiber bundle. For example... Figure 3B As shown, the optical fiber bundle is fixed by the optical fiber bundle fixing device 322 to form an array 324 composed of light-emitting end faces, thereby forming a point light source array.

[0041] Refer to the return Figure 2 The light-transmitting device 214 has a light-transmitting aperture array, such that the point light source array formed by the light-emitting device 212 can form an incident light array, as described above, comprising multiple incident light rays parallel to the main light ray. In some embodiments, the light-transmitting aperture array of the light-transmitting device 214 is configured to limit the diameter of the incident light rays included in the incident light array. The diameter of the light-transmitting aperture can be, for example, 1.8 mm or less, such as 1.5 mm or 1.0 mm. It should be understood that when the diameter of the light-transmitting aperture is 1.5 mm, the diameter of the incident light rays in the incident light array can be limited to 1.5 mm.

[0042] According to embodiments of this disclosure, the arrangement of the light-transmitting aperture array of the light-transmitting device 214 can correspond to the arrangement of the point light source array formed by the light-emitting device 212. For example, Figure 4A and Figure 4B Different examples of point light source array arrangements are shown.

[0043] Figure 4A An array of point light sources arranged in a ring is shown. For example... Figure 4AAs shown, the distance between adjacent point light sources is a certain field of view interval, for example, the range of the field of view interval is not limited to, but is set between 1 and 5 degrees.

[0044] Figure 4B An array of point light sources arranged in a grid pattern is shown. For example... Figure 4B As shown, the distance between adjacent point light sources is a certain interval, for example, the distance between adjacent point light sources can be 0.8-1.5mm. Accordingly, the light aperture array can be arranged in a ring or in a grating pattern.

[0045] Figure 5A and Figure 5B An array of light-transmitting apertures arranged in a ring and an array of light-transmitting apertures arranged in a strip grid pattern are shown respectively. For example, when the emitter 212 is formed as shown... Figure 4A When using the point light source array shown, a device with the following characteristics can be employed: Figure 5A The light-transmitting device 214, shown in the circular array of light-transmitting apertures, forms an incident light array that is also arranged in a circular pattern. When the emitter 212 forms as shown... Figure 4B When using the point light source array shown, a device with the following characteristics can be employed: Figure 5B The light-transmitting device 214, which is an array of light-transmitting apertures arranged in a grating pattern, forms an array of incident light rays arranged in a grating pattern.

[0046] return Figure 1 The incident light array formed by the light-emitting component 110 is reflected by the semi-reflective lens 120 to form multiple main light rays parallel to the optical axis of the system 100. These multiple main light rays are then converged by the first objective lens 130 onto the pupil surface of the eyeball 190 being tested, so as to form a light spot array on the retina of the eyeball 190 being tested.

[0047] The semi-reflective mirror 120 can be used to reflect an array of incident light rays incident upon it. For example, the semi-reflective mirror 120 may include a reflective surface at an angle to the optical axis of the system 100, which reflects the incident light rays formed by the light-emitting component 110 to form multiple main rays parallel to the optical axis of the system 100. It should be understood that the semi-reflective mirror 120 can also be used to transmit light incident upon it; for example, the semi-reflective mirror 120 can also transmit light spots formed on the retina so that they are ultimately imaged onto the photodetector 140. In some embodiments, the semi-reflective and semi-transmissive effect can be achieved by coating.

[0048] The first objective lens 130 can be used to converge multiple beams of principal light formed by reflection from the semi-reflective mirror 120 onto the pupillary surface of the eyeball 190 being tested. The axis of the first objective lens 130 can coincide with the optical axis of the system 100, and the first objective lens 130 can be moved along the optical axis of the system 100 to allow the light to converge from the reflection from the semi-reflective mirror 120 onto the pupillary surface of the eyeball 190 being tested. Figure 2The point light source array formed by the light-emitting device 212 is located on the front focal plane of the first objective lens 130, and the pupil plane of the tested eye 190 is located on the rear focal plane of the first objective lens 130. Thus, the first objective lens 130 allows multiple principal rays parallel to the optical axis of the system 100, formed by reflection from the semi-reflective mirror 120, to converge onto the pupil plane of the tested eye 190, thereby forming a light spot array on the retina of the tested eye 190. It should be understood that the multiple incident rays included in the incident ray array have the same light intensity; therefore, the light intensity distribution of each spot in the light spot array formed on the retina corresponds to the point spread function of each incident ray in the incident ray array formed by the light-emitting component 110 after being focused by the tested eye 190. In other words, through the system 100, the incident ray array formed by the light-emitting component 110 can be projected onto the retina of the tested eye 190 to form a light spot array, where each spot in the light spot array represents the point spread function of the corresponding field of view of the tested eye 190.

[0049] To better form a light spot array on the retina of the tested eye 190 and avoid blurry light spots, in some embodiments, the position of the first objective lens 130 can also be related to the degree of defocus of the tested eye 190. That is, when determining the position of the first objective lens 130, the degree of defocus of the tested eye 190 is additionally considered, so as to compensate for defocus of the tested eye 190 by moving the position of the first objective lens 130. In still other embodiments, a defocus compensation unit can optionally be provided between the light-emitting component 110 of the system 100 and the first objective lens 130 to achieve defocus compensation for the tested eye 190. The following will be combined with Figure 6 The working principle of the defocus compensation unit is explained. Figure 6 A schematic diagram of a defocus compensation unit 600 according to an embodiment of the present disclosure is shown.

[0050] like Figure 6As shown, the defocus compensation unit 600 includes a first prism 610 and a second prism 620. When the defocus compensation unit 600 is placed, for example, in system 100, the first prism 610 and the second prism 620 are arranged along a direction perpendicular to the optical axis of system 100, and the distance between the first prism 610 and the second prism 620 is adjustable. When the distance between the first prism 610 and the second prism 620 increases, for example, by moving the second prism 620 to the position of the second prism 620', the light beam passing through the defocus compensation unit 600 can be focused at a position closer to the defocus compensation unit 600. Conversely, when the distance between the first prism 610 and the second prism 620 decreases, the light beam passing through the defocus compensation unit 600 will be focused at a position farther from the defocus compensation unit 600. Based on this, when the tested eye 190 is hyperopic, i.e., in the case of hyperopic defocus, the distance between the first prism 610 and the second prism 620 is increased; when the tested eye 190 is myopic, i.e., in the case of myopic defocus, the distance between the first prism 610 and the second prism 620 is shortened, so that the light spot is better focused on the retina of the tested eye 190. By setting a defocus compensation unit between the light-emitting component 110 and the first objective lens 130, and further by adjusting the distance between the first prism 610 and the second prism 620, the light spot is better focused on the retina of the tested eye 190. Therefore, this disclosure can improve the subsequent detection efficiency of the light spot, and also makes the system of this disclosure widely applicable to accurately and conveniently measure the optical imaging quality of the eye under different eye conditions. In addition, it also helps to improve the accuracy and sensitivity of using algorithms to calculate the optical imaging quality of the tested eye 190.

[0051] return Figure 1 The photodetector 140 is used to acquire the light spot array formed on the retina and form a corresponding light spot array image, so as to calculate the two-dimensional point spread function of each field of view based on the formed light spot array image, in order to calculate and evaluate the optical imaging quality of the tested eye 190.

[0052] Photodetector 140 is configured to acquire an image of a light spot array corresponding to the light spot array formed on the retina, for use in detecting the optical performance of the retina of the eye 190 under test. Photodetector 140 can be any suitable device capable of detecting light signals and converting them into electrical signals, such as a charge-coupled device (CCD) camera or a complementary metal-oxide-semiconductor (CMOS) camera, without limitation herein.

[0053] In some embodiments, such as Figure 1As shown, the system 100 further includes a second lens 150, an aperture 160, and a second objective lens 170 disposed on the photodetector 140 and the semi-reflective mirror 120, wherein the second objective lens 170, the aperture 160, and the second lens 150 are coaxial and sequentially positioned at a distance from the photodetector 140. The aperture 160 is used to limit the beam diameter and exclude stray light. In some embodiments, the position of the second lens 150 can be adjusted along the optical axis of the system 100, and the second lens 150 is confocal with the first objective lens 130. It should be understood that the light spot array formed on the retina of the tested eye 190 can be detected by the photodetector 140 sequentially via the pupillary surface of the tested eye 190, the first objective lens 130, the semi-reflective mirror 120 (e.g., the transmission surface of the semi-reflective mirror 120), the second lens 150, the aperture 160, and the second objective lens 170, and a light spot array image corresponding to the light spot array formed on the retina of the tested eye 190 is formed on the photodetector 140. The resulting array of light spots can be used to calculate the two-dimensional point spread function of the field of view of the corresponding light spots.

[0054] In some embodiments, control, for example Figure 2 The light-emitting device 212 sequentially illuminates the point light sources in its array, and controls the photodetector to simultaneously acquire the corresponding light spot images formed by each sequentially illuminated point light source on the retina of the tested eye, thereby avoiding overlap between detected pixels and improving spatial resolution. In some other embodiments, the spacing between the point light sources in the array formed by the light-emitting device 212 can be greater than or equal to a predetermined spacing threshold, and the number of point light sources can be less than or equal to a predetermined number threshold, so as to be suitable for detection with lower field-of-view resolution requirements. For example, the light-emitting device 212 can be controlled to illuminate the point light sources in its array simultaneously, and the photodetector can be controlled to simultaneously detect the light spot array formed by the point light source array on the retina of the tested eye, thereby improving the detection speed.

[0055] The system provided by the present invention can not only obtain the optical imaging quality of the central field of view of the retina of the tested eye along the visual axis, but also directly and efficiently measure the optical imaging quality of the peripheral field of view of the retina, thereby realizing rapid detection of the optical quality of the eye in the wide field of view on and off the visual axis. Moreover, it has a simple structure, low cost, and is easy to use, and has significant commercial potential.

[0056] The exemplary embodiments of this disclosure also propose a method by, as in Figure 1The system 100 shown illustrates a method for obtaining the wavefront aberration of the tested eye 190. This method includes: obtaining a two-dimensional point spread function based on each spot image in the spot array image formed on the photodetector 140 as described above; and performing an inverse fit on the two-dimensional point spread function to obtain the wavefront aberration of the tested eye 190.

[0057] Figure 7 A flowchart of a method 700 for obtaining the wavefront aberration of a tested eyeball according to an embodiment of the present disclosure is shown. Method 700 can be performed by, for example... Figure 9 The method is performed at the illustrated electronic device 900. It should be understood that method 700 may also include additional actions not shown and / or the actions shown may be omitted, and the scope of this disclosure is not limited in this respect.

[0058] In step 710, a two-dimensional point spread function (PSF) is obtained based on a spot image from the spot array formed on the photodetector. As mentioned earlier, the spot array formed on the photodetector corresponds to the spot array formed on the retina of the tested eye. Therefore, the obtained two-dimensional point spread function corresponds to the spot in the spot array formed on the retina of the tested eye that corresponds to the aforementioned spot image and its field of view. The two-dimensional point spread function can be represented as PSF(x, y), where the parameters x and y represent the position coordinates of the spot, respectively.

[0059] According to embodiments of this disclosure, based on the obtained two-dimensional point spread function PSF(x, y), its Strehl ratio can be calculated to reflect the influence of system aberrations on the intensity of the imaged light spot. In other words, by calculating the Strehl ratio of the two-dimensional point spread function PSF(x, y), the light intensity distribution of the light spot array image formed on the photodetector can be obtained, thereby obtaining a quantitative evaluation index of the optical imaging quality at the corresponding field of view.

[0060] According to embodiments of this disclosure, based on the obtained two-dimensional point spread function PSF(x, y), a Fourier transform can be performed on it to obtain the optical transfer function OTF(u, v) = FT{PSF(x, y)} for the corresponding field of view to evaluate the optical imaging quality of the corresponding field of view. In the optical transfer function OTF(u, v), the parameters u and v represent the spatial frequency coordinates in the frequency domain, respectively.

[0061] According to embodiments of this disclosure, the wavefront aberration of the tested eyeball can also be obtained based on the obtained two-dimensional point spread function PSF(x, y).

[0062] In step 720, the two-dimensional point spread function is backfitted to obtain the wavefront aberration of the tested eye. Wavefront aberration refers to the deviation between the ideal wavefront and the actual wavefront of the optical system, reflecting the aberrations present in the actual optical system. Wavefront aberration can be decomposed according to polynomials. For example, it can be decomposed according to Zernike polynomials to divide it into low-order and high-order aberrations. Low-order aberrations include parameters in traditional medical optometry such as defocus and astigmatism, which are closely related to the occurrence and development of myopia. The following will combine... Figure 8 The process of obtaining the wavefront aberration of the tested eyeball through inverse fitting is further explained.

[0063] Figure 8 A flowchart of a method 700 for inverse fitting a two-dimensional point spread function to obtain the wavefront aberration of a tested eyeball according to an embodiment of the present disclosure is shown. Method 700 can be performed by, for example... Figure 9 The method is performed at the illustrated electronic device 900. It should be understood that the method 800 may also include additional actions not shown and / or the actions shown may be omitted, and the scope of this disclosure is not limited in this respect.

[0064] In step 810, the initial values ​​of the wavefront aberration polynomial are set. Taking the Zernike polynomial as an example, the wavefront aberration can be expanded according to the Zernike polynomial. Equation (1) shows the wavefront aberration polynomial W(α, β) obtained from the Zernike polynomial decomposition:

[0065]

[0066] In the above formula (1), α and β are normalized pupil coordinates. Let c(n, m) represent a single term in the wavefront aberration polynomial, and c(n, m) represent the corresponding term. The coefficients of a single term, where n is the radial angle, representing the nth-order aberration; and m is the azimuth frequency. Generally, the aberrations of the human eye can be determined based on the coefficients in the wavefront aberration polynomial. According to an embodiment of this disclosure, firstly, the initial value of the wavefront aberration polynomial W(α, β) can be set based on, for example, the average level of the eye condition of a normal person (such as the average value of wavefront aberrations), or the initial value of the wavefront aberration polynomial W(α, β) can be set to 0, and the wavefront aberration polynomial W(α, β) with initial coefficients can be obtained based on the set initial value.

[0067] In step 820, the pupil function p(α, β) is calculated based on the wavefront aberration polynomial W(α, β) of the current coefficients. For example, the pupil function p(α, β) can be represented by the following formulas (2) and (3).

[0068]

[0069] p(α,β)=0α 2 +β 2 ≥1 (3)

[0070] In the above formulas (2) and (3), λ represents the wavelength of light; α and β represent the normalized pupil coordinates.

[0071] In step 830, the point spread function PSF′(x, y) is calculated based on the pupil function p(α, β). Equation (4) shows an example expression for the point spread function PSF′(x, y).

[0072]

[0073] In the above formula (4), f is the focal length of the eyeball being tested.

[0074] In step 840, for each corresponding field of view corresponding to the retinal region, the point spread function calculated in step 830 is compared with the two-dimensional point spread function obtained in step 710.

[0075] According to one embodiment of this disclosure, it is possible to... Figure 7 In step 710, the two-dimensional point spread function of the retinal region corresponding to the i-th field of view obtained based on the light spot array image formed on the photodetector is represented as PSF. i0 (x, y), and the point spread function of the retinal region corresponding to the i-th field of view angle calculated based on the pupil function p(α, β) at step 830 is represented as PSF′. i (x, y), and thus establish an evaluation function M(i) for the retinal region corresponding to the i-th field of view. For example, it can be based on PSF. i0 (x, y) and PSF′ i The evaluation function M(i) is established as shown in the following formula (5) for (x, y).

[0076]

[0077] In step 850, it is determined whether the relationship between the calculated point spread function and the two-dimensional point spread function satisfies the threshold condition. For example, the evaluation function M(i) at step 840 can be compared with the target threshold to determine whether the evaluation function M(i) reaches the target threshold. If the evaluation function M(i) reaches the target threshold, that is, the relationship between the calculated point spread function and the two-dimensional point spread function satisfies the threshold condition, then in step 860, the wavefront aberration polynomial W(α, β) of the current coefficients is output as the wavefront aberration of the tested eye.

[0078] If the evaluation function M(i) does not reach the target threshold, proceed to step 870 to adjust the current coefficients of the wavefront aberration polynomial W(α, β). Then, return to step 820 to recalculate the pupil function p(α, β) based on the adjusted coefficients of the wavefront aberration polynomial W(α, β). That is, if in step 850 the relationship between the calculated point spread function and the two-dimensional point spread function does not meet the threshold condition, adjust the coefficients of the wavefront aberration polynomial W(α, β) and repeat steps 820 to 850 until the relationship between the calculated point spread function and the two-dimensional point spread function meets the threshold condition, i.e., the evaluation function M(j) reaches the target threshold. Then, output the wavefront aberration polynomial W(α, β) with the current coefficients as the wavefront aberration of the tested eye.

[0079] According to the method provided in this disclosure, the wavefront aberration of the tested eyeball is obtained iteratively. For the retinal region corresponding to each field of view, each iteration optimizes the wavefront aberration distribution of the tested eyeball based on the difference between the two-dimensional point spread function obtained from each spot image in the spot array image formed on the photodetector and the point spread function obtained through iterative calculation. Based on the obtained wavefront aberration distribution of the tested eyeball, defocus, horizontal astigmatism, oblique astigmatism, spherical aberration, and coma of the tested eyeball can be calculated, and the corresponding refractive power value of the tested eyeball, the aberration distribution map of the peripheral field of view of the retina, and the retinal refractive topography map can be further obtained.

[0080] In summary, the system and method for ocular optical detection provided in this disclosure can rapidly detect the optical imaging quality of the tested eyeball in the visual axis and in the wide field of view outside the visual axis, and can be used in various scenarios such as monitoring the refractive development of children and adolescents' eyes, myopia prevention and control examinations, dry eye examinations, and cataract examinations.

[0081] Figure 9 A block diagram schematically illustrates a computing device 900 suitable for implementing embodiments of the present disclosure. Device 900 may be used to implement execution... Figure 7 Method 700 shown Figure 8 The device shown in method 800. (As...) Figure 9 As shown, device 900 includes a central processing unit (CPU) 901, which can perform various appropriate actions and processes according to computer program instructions stored in read-only memory (ROM) 902 or loaded from storage unit 908 into random access memory (RAM) 903. RAM 903 may also store various programs and data required for the operation of device 900. CPU 901, ROM 902, and RAM 903 are interconnected via bus 904. Input / output (I / O) interface 905 is also connected to bus 904.

[0082] Multiple components in device 900 are connected to I / O interface 905, including: input unit 906, output unit 907, and storage unit 908. Processing unit 901 executes the various methods and processes described above, such as executing method 700 or method 800. For example, in some embodiments, method 700 or method 800 may be implemented as a computer software program stored on a machine-readable medium, such as storage unit 908. In some embodiments, part or all of the computer program may be loaded and / or installed onto device 900 via ROM 902 and / or communication unit 909. When the computer program is loaded into RAM 903 and executed by CPU 901, one or more operations of method 700 or method 800 described above may be performed. Alternatively, in other embodiments, CPU 901 may be configured to execute one or more actions of method 700 or method 800 by any other suitable means (e.g., by means of firmware).

[0083] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0084] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute 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 a remote computer, the remote computer may 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 may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0085] These computer-readable program instructions can be provided to a processor, general-purpose computer, special-purpose computer, or other programmable data processing unit in a voice interaction device to produce a machine such that, when executed by the processing unit of the computer or other programmable data processing device, these instructions create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium, causing a computer, programmable data processing device, and / or other device to operate in a particular manner.

[0086] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

[0087] The above are merely optional embodiments of this disclosure and are not intended to limit this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A system for optical detection of the eye, comprising: A light-emitting component is configured to form an array of incident rays, the array of incident rays comprising multiple incident rays parallel to the main ray; A semi-reflective mirror, wherein the reflecting surface of the semi-reflective mirror is configured at an angle to the optical axis of the system to reflect the incident light array to form multiple main rays parallel to the optical axis of the system; The first objective lens, whose axis coincides with the optical axis of the system, is used to converge the multiple main rays formed by the reflection of the semi-reflective lens onto the pupillary surface of the eye being tested, so as to form a light spot array on the retina of the eye being tested. The pupillary surface of the eye being tested is located on the back focal plane of the first objective lens, and each light spot in the light spot array represents the point spread function of the corresponding field of view of the eye being tested. as well as A photodetector is configured to acquire an image of a light spot array corresponding to the light spot array, for use in detecting the optical performance of the retina of the eye being tested; The incident light array comprises multiple incident light beams with the same light intensity, and the light-emitting component includes: Light-emitting devices, used to form point light source arrays; as well as A light-transmitting device having a light-transmitting aperture array for causing the point light source array to form the incident light array via the light-transmitting aperture array; The light-emitting device includes a coaxially arranged light source, a first lens, a diffusion plate, and a pinhole array. The light emitted by the light source passes sequentially through the first lens, the diffusion plate, and the pinhole array to form the point light source array.

2. The system according to claim 1, wherein, The light-transmitting device's light-transmitting aperture array is configured to limit the diameter of the incident light rays included in the incident light ray array formed by the light-emitting component.

3. The system according to claim 1, wherein, The arrangement of the light-transmitting aperture array corresponds to the arrangement of the resulting point light source array.

4. The system according to claim 1, wherein, The resulting point light source array is located on the front focal plane of the first objective lens.

5. The system according to claim 1, further comprising: A second objective lens, an aperture, and a second lens are placed sequentially and coaxially from the photodetector, and the second lens is confocal with the first objective lens.

6. The system according to claim 5, wherein, The light spot array formed on the retina of the eye being tested is detected by the photodetector in sequence via the pupillary surface of the eye being tested, the first objective lens, the semi-reflective lens, the second lens, the aperture stop, and the second objective lens, and a light spot array image corresponding to the light spot array is formed on the photodetector.

7. The system according to claim 1, further comprising: A defocus compensation unit is disposed between the light-emitting component and the first objective lens. The defocus compensation unit includes a first prism and a second prism disposed along a direction perpendicular to the optical axis. The distance between the first prism and the second prism is adjustable so that the light spot array is formed on the retina of the eye being tested.

8. A method for obtaining wavefront aberrations of a tested eyeball using the system according to any one of claims 1-7, the method comprising: Based on a spot image in the light spot array formed on the photodetector, a two-dimensional point spread function is obtained for the spot image. This two-dimensional point spread function corresponds to the spot in the light spot array formed on the retina of the tested eye that corresponds to the spot image and its field of view. The wavefront aberration of the tested eyeball is obtained by backfitting the two-dimensional point spread function.

9. The method according to claim 8, wherein, Inverse fitting of the two-dimensional point spread function to obtain the wavefront aberration of the tested eyeball includes: The pupil function is calculated using a wavefront aberration polynomial based on the current coefficients. Calculate the point extension function based on the pupil function; For each corresponding retinal region at a given field of view, the calculated point spread function is compared with the two-dimensional point spread function to determine whether the relationship between the calculated point spread function and the two-dimensional point spread function satisfies a threshold condition; and In response to the relationship between the calculated point spread function and the two-dimensional point spread function satisfying a threshold condition, the wavefront aberration polynomial of the current coefficients is output as the wavefront aberration of the tested eyeball.

10. The method of claim 9, further comprising: In response to the fact that the relationship between the calculated point spread function and the two-dimensional point spread function does not meet the threshold condition, the current coefficients of the wavefront aberration polynomial are adjusted, and the pupil function and the point spread function are recalculated based on the adjusted coefficients of the wavefront aberration polynomial until the relationship between the recalculated point spread function and the two-dimensional point spread function meets the threshold condition.

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