Optical system and method for measuring axial length of eye

Abstract

The invention discloses an optical system and method for measuring the axial length of the eye, the optical system comprises an OCT light source module, an OCT imaging module, a posterior segment OCT sample arm module and an anterior segment fracture imaging assembly, the OCT light source module provides measuring light, the measuring light penetrates through the posterior segment OCT sample arm module and then enters the fundus of the human eye to be measured, and the anterior segment fracture imaging assembly is used for imaging the anterior segment fracture. The OCT imaging module receives the measuring light to obtain a posterior segment OCT image; the anterior segment fissure imaging assembly comprises an anterior segment fissure light source module, an anterior segment fissure imaging module and an anterior segment fissure imaging adjusting light path module, the anterior segment fissure light source module provides fissure light, and the fissure light penetrates through the anterior segment fissure imaging adjusting light path module and then is focused on the anterior segment of a person to be detected; the anterior segment fissure imaging module receives the fissure light to obtain an anterior segment fissure image; and respectively acquiring first optical path data and second optical path data by using the posterior segment OCT image and the anterior segment fracture image so as to calculate the axial length of the eye. According to the invention, the influence of eye movement of the to-be-measured eye is avoided, and the eye axis length measurement precision is improved.

Description

[0001] This application claims priority to a Chinese patent application filed with the China Patent Office on November 20, 2023, with application number 202311547355.8 and application name “An optical system and method for measuring axial length of the eye”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of medical devices, and in particular to an optical system and method for measuring axial length of an eye. Background Art

[0003] Nowadays, more and more elderly people suffer from cataracts, and transplanting artificial lenses is an effective and widely used treatment for cataracts. However, the calculation of artificial lenses requires many parameters, such as corneal anterior and posterior surface curvature, corneal thickness, anterior chamber depth, lens thickness, lens anterior and posterior surface curvature, axial length, white to white distance, pupil diameter, etc. There are many parameters to be measured, but it often requires multiple medical equipment to detect before the above complete data can be obtained. Therefore, if a medical device that can obtain the above data can be realized with one device, it can not only improve the convenience of measurement for patient detection, but also improve the accuracy of measurement. In addition, with the increase in the number of myopic teenagers, the situation of myopia prevention and control is becoming more and more severe, and measuring the axial length is an important reference indicator for myopia prevention and control. Therefore, how to simply and cheaply realize the measurement of many ophthalmic indicators is the development trend of ophthalmic medical equipment.

[0004] Optical coherence tomography (OCT) is an emerging optical imaging technology. Compared with traditional clinical imaging methods, it has the advantages of high resolution, fast imaging speed, no radiation damage, moderate price, and compact structure. It is an important potential tool for basic medical research and clinical diagnosis applications. Currently, among the various ophthalmic devices using optical instruments, OCT devices used for ophthalmic examination and treatment have become an indispensable ophthalmic device for the diagnosis of ophthalmic diseases.

[0005] In patent document 201911073986.4, lateral corneal imaging is used to correct the influence of eye movement during axial length measurement, but lateral corneal imaging is easily affected by ambient light, and the cornea is relatively transparent, making it difficult to identify the corneal vertex, so the error is large. In patent documents 201410135999.0 and patent document 202011120798.5, anterior and posterior segment OCT switching technology is used to achieve corneal and posterior segment OCT imaging to measure axial length, but the anterior and posterior segment OCT switching process takes a long time, which may be affected by eye movement, resulting in a decrease in the reliability of axial length measurement.

[0006] The disclosure of the above background technology content is only used to assist in understanding the concept and technical solution of the present invention. It does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above content has been disclosed on the filing date of this patent application, the above background technology should not be used to evaluate the novelty and creativity of the present application. Summary of the invention

[0007] In order to solve the above technical problems, the present invention proposes an optical system and method for measuring the axial length of the eye, which avoids the influence of the eye movement of the person to be measured and improves the measurement accuracy of the axial length of the eye.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention discloses an optical system for measuring the axial length of an eye, comprising an OCT light source module, an OCT imaging module, a posterior segment OCT sample arm module, and an anterior segment fissure imaging component, wherein:

[0010] The OCT light source module is used to provide measurement light, and the measurement light passes through the posterior segment OCT sample arm module and then enters the fundus of the human eye to be tested, and the OCT imaging module receives the measurement light returned by the fundus of the human eye to be tested to obtain a posterior segment OCT image;

[0011] The anterior segment slit imaging assembly comprises an anterior segment slit light source module, an anterior segment slit imaging module and an anterior segment slit imaging light path adjustment module, wherein the anterior segment slit light source module is used to provide slit light, and the slit light passes through the anterior segment slit imaging light path adjustment module and is focused on the anterior segment of the eye of the person to be tested, and the anterior segment slit imaging module receives the returned slit light to obtain an anterior segment slit image;

[0012] The first optical path data and the second optical path data are acquired respectively by using the posterior segment OCT image and the anterior segment fissure image, and the axial length of the eye is calculated by using the first optical path data and the second optical path data.

[0013] Preferably, the anterior segment slit imaging module includes an anterior segment slit imaging lens 1801 and an anterior segment slit imaging device 1803. The slit light emitted by the anterior segment slit light source module is focused on the anterior segment of the eye of the person to be tested, and the returning anterior segment slit light signal passes through the anterior segment slit imaging lens 1801 and is received by the anterior segment slit imaging device 1803. The anterior segment slit imaging device 1803 obtains an anterior segment slit image according to the anterior segment slit light signal.

[0014] Preferably, the anterior segment slit imaging adjustment optical path module includes an eye-viewing objective lens 1305, which is located on the optical path in the first direction, wherein the optical path in the first direction is perpendicular to the human eye to be tested, and the anterior segment slit imaging lens 1801 and the anterior segment slit imaging device 1803 are respectively arranged below the eye-viewing objective lens 1305.

[0015] Preferably, the anterior segment slit light source module includes an anterior segment slit light source 1809 and a front beam splitter 1303. The slit light emitted by the anterior segment slit light source 1809 passes through the front beam splitter 1303 and then through the anterior segment slit imaging adjustment optical path module to be focused on the anterior segment of the person to be tested.

[0016] Preferably, the posterior segment OCT sample arm module includes an optical path scanning device 1109 and a posterior segment OCT imaging adjustment optical path unit, the posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror 1501 form an anterior segment OCT imaging adjustment optical path unit, the anterior segment slit imaging adjustment optical path module adopts the anterior segment OCT imaging adjustment optical path unit, and the anterior segment slit light source module adopts the OCT light source module and the optical path scanning device 1109 to generate slit light, wherein the measurement light provided by the OCT light source module is scanned in one dimension by the optical path scanning device 1109 to emit slit light and pass through the anterior segment OCT imaging adjustment optical path unit and then focus on the anterior segment of the eye of the person to be measured.

[0017] Preferably, the posterior segment OCT sample arm module includes an optical path scanning device 1109 and a posterior segment OCT imaging adjustment optical path unit, the posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror 1501 form an anterior segment OCT imaging adjustment optical path unit, the anterior segment slit imaging adjustment optical path module adopts the anterior segment OCT imaging adjustment optical path unit, the anterior segment slit light source module adopts an anterior segment slit light source 3809, a wavelength division multiplexer 3807, an optical fiber 1106 and the optical path scanning device 1109 to generate slit light, the light output by the anterior segment slit light source 3809 is coupled by the wavelength division multiplexer 3807 and then transmitted to the optical fiber 1106, the light beam output from the optical fiber 1106 is scanned in one dimension by the optical path scanning device 1109, emits slit light and passes through the anterior segment OCT imaging adjustment optical path unit and then focuses on the anterior segment of the eye of the person to be tested.

[0018] Preferably, the posterior segment OCT sample arm module includes an optical path scanning device 1109 and a posterior segment OCT imaging adjustment optical path unit, the posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror 1501 form an anterior segment OCT imaging adjustment optical path unit, the anterior segment slit imaging adjustment optical path module adopts the anterior segment OCT imaging adjustment optical path unit, the anterior segment slit light source module adopts the anterior segment slit light source 4809, parallel optical fibers 2106 and the optical path scanning device 1109 to generate slit light, the light output by the anterior segment slit light source 4809 passes through the parallel optical fibers 2106, and the light beam output by the parallel optical fibers 2106 is scanned in one dimension by the optical path scanning device 1109 to emit slit light and pass through the anterior segment OCT imaging adjustment optical path unit and then focus on the anterior segment of the person to be tested.

[0019] Preferably, the posterior segment OCT sample arm module includes an optical path scanning device 1109 and a posterior segment OCT imaging adjustment optical path unit, the anterior segment slit imaging adjustment optical path module adopts the posterior segment OCT imaging adjustment optical path unit, and the anterior segment slit light source module includes an anterior segment slit light source 5809, a lens 5807 and a spectroscope 5805. The anterior segment slit light source 5809 emits light, passes through the lens 5807, is reflected by the spectroscope 5805, and then is scanned in one dimension by the optical path scanning device 1109 to form slit light, and then passes through the anterior segment slit imaging adjustment optical path module to be focused on the anterior segment of the person to be tested.

[0020] Preferably, the posterior segment OCT imaging adjustment optical path unit comprises a posterior segment OCT field lens 1301, a front beam splitter 1303 and an eyepiece objective lens 1305; the measurement light provided by the OCT light source module is reflected by the optical path scanning device 1109, passes through the posterior segment OCT field lens 1301, and then is reflected by the front dichroic mirror 1303 to the eyepiece objective lens 1305, and converges to the fundus of the eye of the person to be tested through the eye to be tested, so as to return the posterior segment light signal to the OCT imaging module, and the OCT imaging module obtains the posterior segment OCT image according to the posterior segment light signal;

[0021] The anterior segment OCT imaging adjustment optical path unit is formed by inserting an anterior segment OCT insertion mirror 1501 into the optical path formed by the posterior segment OCT imaging adjustment optical path unit. The slit light passes through the posterior segment OCT field lens 1301 and the anterior segment OCT insertion mirror 1501 in sequence, and then is reflected by the front dichroic mirror 1303 to the eye-receiving objective lens 1305, and converges on the anterior segment of the eye of the person to be tested, so as to return the anterior segment slit light signal to the anterior segment slit imaging module, and the anterior segment slit imaging module obtains the anterior segment slit image according to the anterior segment slit light signal.

[0022] Preferably, the first optical path data refers to the optical path hRetinal from the top of the posterior segment OCT image to the retinal signal in the posterior segment OCT image measured according to the posterior segment OCT image of the human eye to be tested, and the second optical path data refers to the optical path hCornea from the top of the anterior segment fissure image to the corneal vertex of the human eye to be tested measured according to the anterior segment fissure image of the human eye to be tested;

[0023] The axial length of the eye is calculated using the first optical path data and the second optical path data, including: calculating the axial length Leye of the human eye to be tested based on the optical path change X of the posterior segment OCT sample arm module when acquiring the posterior segment OCT image of the human eye to be tested and the measured optical path hRetinal and optical path hCornea.

[0024] In a second aspect, the present invention discloses a method for measuring the axial length of an eye, characterized in that the axial length of an eye to be measured is measured using the optical system described in the first aspect, comprising the following steps:

[0025] Acquire the posterior segment OCT image of the human eye to be tested, and measure the optical path hRetinal from the top of the posterior segment OCT image to the retinal signal in the posterior segment OCT image according to the posterior segment OCT image of the human eye to be tested;

[0026] Acquire an anterior segment fissure image of the human eye to be tested, and measure an optical path hCornea from the top of the anterior segment fissure image to the corneal vertex of the human eye to be tested according to the anterior segment fissure image of the human eye to be tested;

[0027] The axial length Leye of the human eye to be tested is calculated according to the optical path change X of the posterior segment OCT sample arm module when acquiring the posterior segment OCT image of the human eye to be tested and the measured optical path hRetinal and optical path hCornea.

[0028] Preferably, the axial length Leye of the human eye to be measured is calculated using the following formula:

[0029] Leye=△L+X-hCornea+hRetinal;

[0030] Wherein, △L represents the spatial distance between the top of the posterior segment OCT image and the top of the anterior segment fissure image, and X represents the optical path change of the posterior segment OCT sample arm module when acquiring the posterior segment OCT image of the human eye to be tested.

[0031] Compared with the prior art, the beneficial effect of the present invention lies in: the optical system and method for measuring axial length proposed in the present invention further measures the axial length by respectively acquiring the posterior segment OCT image and the anterior segment fissure image, wherein the accurate positioning of the cornea is achieved by anterior segment fissure imaging, and combined with the posterior segment OCT image acquisition, the switching time can be reduced or even no switching is required, thereby avoiding the influence of the eye movement of the person to be measured and improving the accuracy of axial length measurement.

[0032] In a further scheme, by adding an anterior segment slit light source that generates slit light separately, and using different imaging schemes to obtain the posterior segment OCT image and the anterior segment slit image, the two can be acquired at the same time, thereby avoiding the influence of the eye movement of the person to be measured to the greatest extent and further improving the measurement accuracy of the axial length.

[0033] In a further scheme, the OCT light source module or a separately provided anterior segment slit light source is combined with an optical path scanning device to generate slit light, and the optical path unit is further adjusted in combination with the anterior segment OCT imaging, so that the slit light can be focused on the cornea of ​​the person to be tested, and the anterior segment slit image is further obtained; this scheme does not require additional debugging of an optical path, which can reduce the difficulty of system debugging and improve the speed of system debugging; and between obtaining the posterior segment OCT image and the anterior segment slit image, only the anterior segment OCT insertion mirror needs to be adjusted without adjusting the optical path, and the switching time is shorter, which is faster than the switching time of the prior art, and it is easier to avoid the influence of eye movement when measuring the axial length. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic structural diagram of an ophthalmic optical biometry system according to a first embodiment of the present invention;

[0035] Figure 2 yes Figure 1 Optical path diagram of the posterior segment OCT imaging system of the Zhong Ophthalmology Optical Biometry System;

[0036] Figure 3 yes Figure 1 Optical path diagram of the anterior segment OCT imaging system of the Zhong Ophthalmology Optical Biometry System;

[0037] Figure 4a yes Figure 1 A front view of the anterior segment camera module of the Zhong Ophthalmic Optical Biometry System;

[0038] Figure 4b yes Figure 1 A top view of the anterior segment camera module of the ophthalmic optical biometry system;

[0039] Figure 5 yes Figure 1 Optical path diagram of anterior segment fissure imaging of the mid-ophthalmology optical biometry system;

[0040] Figure 6 yes Figure 1 Schematic diagram of the fixation optical module of the meso-ophthalmic optical biometry system;

[0041] Figure 7 It is a schematic diagram of the measurement of axial length of the eye;

[0042] Figure 8 is a schematic structural diagram of an ophthalmic optical biometry system according to a second embodiment of the present invention;

[0043] Fig. 9 yes Figure 8 Optical path diagram of anterior segment fissure imaging of the mid-ophthalmology optical biometry system;

[0044] Fig.10 yes Figure 8 Schematic diagram of the fixation optical module of the meso-ophthalmic optical biometry system;

[0045] Fig.11 is a schematic structural diagram of an ophthalmic optical biometry system according to a third embodiment of the present invention;

[0046] Fig.12 yes Fig.11 Schematic diagram of the structure of the optical fiber of the ophthalmic optical biometry system;

[0047] Fig.13 yes Fig.11 Optical path diagram of the posterior segment OCT imaging system of the Zhong Ophthalmology Optical Biometry System;

[0048] Fig.14 yes Fig.11 Optical path diagram of the anterior segment OCT imaging system of the Zhong Ophthalmology Optical Biometry System;

[0049] Fig.15 yes Fig.11 Optical path diagram of anterior segment fissure imaging of the mid-ophthalmology optical biometry system;

[0050] Fig.16 is a schematic structural diagram of an ophthalmic optical biometry system according to a fourth embodiment of the present invention;

[0051] Fig.17 yes Fig.16 Schematic diagram of the structure of parallel optical fibers in the ophthalmic optical biometry system;

[0052] Fig.18 It is a schematic diagram of the structure of parallel optical fibers in the prior art;

[0053] Fig.19 yes Fig.16 Optical path diagram of anterior segment fissure imaging of the mid-ophthalmology optical biometry system;

[0054] Fig. 20 is a schematic structural diagram of an ophthalmic optical biometry system according to a fifth embodiment of the present invention;

[0055] Fig.21 yes Fig. 20 Diagram of the optical path for anterior segment fissure imaging in the ophthalmic optical biometry system.

[0056] Description of reference numerals: 10, probe module; 1101, OCT light source; 1103, fiber coupler; 1105, polarization controller; 1106, optical fiber; 11061, fiber core; 11063, cladding; 11065, sheath; 1107, fiber collimator; 1109, optical path scanning device; 11091, X-direction scanning device; 11093, Y-direction scanning device; 1120, reference arm module; 1141, detector; 1143, computer; 1301, posterior segment OCT field lens; 1303, front beam splitter; 1305, eyepiece objective lens; 1501, anterior segment OCT insertion lens; 1701, fixation light source; 1703, fixation light path lens; 18, combination module; 1801, anterior segment slit imaging lens; 1803, anterior segment slit imaging device; 1807, angular beam splitter; 1809, anterior segment slit light source; 1901, illumination light source; 1903, rainbow injection relay mirror; 1905, rainbow injection spectroscope; 1907, anterior segment camera mirror; 1909, anterior segment camera device; E, human eye to be tested; Er, fundus; L1, optical axis; 2106, parallel optical fiber; 21061, OCT optical path core; 21062, anterior segment slit illumination optical path core; 21063, OCT optical path cladding; 21065, sheath ; 3106, dual-core optical fiber; 31061, fiber core; 31062, fiber core; 31063, fiber cladding; 31064, fiber cladding; 31065, sheath; 31066, sheath; 31069, large sheath; 3807, wavelength division multiplexer; 3809, anterior segment slit light source; 4809, anterior segment slit light source; 5805, spectroscope; 5807, lens; 5809, anterior segment slit light source. DETAILED DESCRIPTION

[0057] The present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. The same reference numerals represent the same components unless otherwise specified. It should be emphasized that the following description is merely exemplary and is not intended to limit the scope of the present invention and its application.

[0058] The present invention is described in detail below through specific embodiments in conjunction with the accompanying drawings to provide a better understanding of the present invention, but the following embodiments do not limit the scope of the present invention. In addition, it should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and the drawings only show components related to the present invention rather than the number, shape and size of components in actual implementation. The shape, quantity and proportion of each component in actual implementation may be changed at will, and the component layout may also be more complicated.

[0059] It should be understood that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “inside”, “outside”, “left” and “right” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of the present invention and simplifying the description. They do not indicate or imply that the devices or elements referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0060] The ophthalmic optical biometric system proposed in the present invention is mainly used for measuring the optical parameters related to the patient's eye and examining the patient's eye, and can measure many ophthalmological related parameters such as the human anterior segment OCT image, the posterior segment OCT image, the anterior segment video, the human eye axial length, the anterior chamber depth, the white-to-white distance, etc. Among them, it is mainly based on optical coherence tomography technology, combined with the anterior and posterior segment OCT acquisition technology, the anterior segment fissure imaging, and the anterior segment video technology to achieve the measurement of relevant ophthalmic parameters such as the human eye axial length. Through iris recognition technology, anterior segment OCT image automatic recognition technology, posterior segment OCT image automatic recognition technology and other technologies, the system can achieve full automatic detection. Among them, the axial length measurement technology is to accurately locate the position of the cornea (i.e., the anterior segment) through anterior segment fissure imaging, and then combine the posterior segment OCT acquisition technology to achieve it.

[0061] The present invention adopts an anterior and posterior segment fast switching OCT system, combined with anterior segment camera and automatic recognition technology, which can solve the detection of many optical parameters of the human eye; thereby meeting the needs of measuring different parts, and can obtain accurate data of many important parameters of the human eye, meeting the needs of doctors for clinical diagnosis. Through iris recognition technology, anterior segment OCT image automatic recognition technology, posterior segment OCT image automatic recognition technology and other technologies, the system can achieve full automatic detection.

[0062] A preferred embodiment 1 of the present invention discloses an optical system for measuring axial length of the eye, comprising an OCT light source module, an OCT imaging module, a posterior segment OCT sample arm module, and an anterior segment slit imaging component, wherein: the OCT light source module is used to provide measurement light, the measurement light passes through the posterior segment OCT sample arm module and then enters the fundus of the eye of a person to be measured, the OCT imaging module receives the measurement light returned by the fundus of the eye of the person to be measured, so as to obtain an OCT image of the posterior segment of the eye; the anterior segment slit imaging component comprises an anterior segment slit light source module, an anterior segment slit imaging module, and an anterior segment slit imaging adjustment optical path module, the anterior segment slit light source module is used to provide slit light, the slit light passes through the anterior segment slit imaging adjustment optical path module and then focuses on the anterior segment of the eye of the person to be measured, the anterior segment slit imaging module receives the returned slit light, so as to obtain an anterior segment slit image; the posterior segment OCT image and the anterior segment slit image are used to respectively obtain first optical path data and second optical path data, and the axial length of the eye is calculated using the first optical path data and the second optical path data.

[0063] Among them, the first optical path data refers to the optical path hRetinal from the top of the posterior segment OCT image to the retinal signal in the posterior segment OCT image measured according to the posterior segment OCT image of the human eye to be tested, and the second optical path data refers to the optical path hCornea from the top of the anterior segment fissure image to the corneal vertex of the human eye to be tested measured according to the anterior segment fissure image of the human eye to be tested; the axial length of the eye is calculated using the first optical path data and the second optical path data, including: the axial length Leye of the human eye to be tested is calculated according to the optical path change X of the posterior segment OCT sample arm module when obtaining the posterior segment OCT image of the human eye to be tested and the measured optical path hRetinal and optical path hCornea.

[0064] Among them, the anterior segment fissure imaging module includes an anterior segment fissure imaging lens 1801 and an anterior segment fissure imaging device 1803. The fissure light emitted by the anterior segment fissure light source module is focused on the anterior segment of the human eye to be tested, and the anterior segment fissure light signal returned to the anterior segment fissure passes through the anterior segment fissure imaging lens 1801 and is received by the anterior segment fissure imaging device 1803. The anterior segment fissure imaging device 1803 obtains an anterior segment fissure image according to the anterior segment fissure light signal. Further, the anterior segment fissure imaging adjustment optical path module includes an eyepiece objective lens 1305, which is located on the optical path of the first direction, wherein the optical path of the first direction is perpendicular to the human eye to be tested, and the anterior segment fissure imaging lens 1801 and the anterior segment fissure imaging device 1803 are respectively arranged below the eyepiece objective lens 1305. The anterior segment fissure imaging modules in the following embodiments 1 to 4 all adopt this structure.

[0065] In some preferred embodiments, such as the following embodiment 1, the anterior segment slit light source module includes an anterior segment slit light source 1809 and a front beam splitter 1303. The anterior segment slit light source 1809 emits slit light, which passes through the front beam splitter 1303 and then passes through the anterior segment slit imaging optical path adjustment module and is focused on the anterior segment of the eye of the person to be tested. Specifically, the anterior segment slit light source 1809 emits slit light, which is reflected by the angle beam splitter 1807 and then by the iris beam splitter 1905, and then passes through the iris relay lens 1903 and the front beam splitter 1303, and then passes through the eyepiece objective lens 1305 and is focused on the anterior segment of the eye of the person to be tested.

[0066] In some preferred embodiments, such as the following embodiment 2, the posterior segment OCT sample arm module includes an optical path scanning device 1109 and a posterior segment OCT imaging adjustment optical path unit, the posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror 1501 form an anterior segment OCT imaging adjustment optical path unit, the anterior segment slit imaging adjustment optical path module adopts the anterior segment OCT imaging adjustment optical path unit, and the anterior segment slit light source module adopts the OCT light source module and the optical path scanning device 1109 to generate slit light, wherein the measurement light provided by the OCT light source module is scanned in one dimension by the optical path scanning device 1109 to emit slit light and pass through the anterior segment OCT imaging adjustment optical path unit to focus on the anterior segment of the person to be measured.

[0067] In some preferred embodiments, such as the following embodiment three, the posterior segment OCT sample arm module includes an optical path scanning device 1109 and a posterior segment OCT imaging adjustment optical path unit, the posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror 1501 form the anterior segment OCT imaging adjustment optical path unit, the anterior segment slit imaging adjustment optical path module adopts the anterior segment OCT imaging adjustment optical path unit, the anterior segment slit light source module adopts the anterior segment slit light source 3809, a wavelength division multiplexer 3807, an optical fiber 1106 and an optical path scanning device 1109 to generate slit light, the light output by the anterior segment slit light source 3809 is coupled by the wavelength division multiplexer 3807 and then transmitted to the optical fiber 1106, the light beam output from the optical fiber 1106 is scanned in one dimension by the optical path scanning device 1109, emits slit light and passes through the anterior segment OCT imaging adjustment optical path unit and then focuses on the anterior segment of the person to be tested.

[0068] In some preferred embodiments, such as the following embodiment four, the posterior segment OCT sample arm module includes an optical path scanning device 1109 and a posterior segment OCT imaging adjustment optical path unit, the posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror 1501 form an anterior segment OCT imaging adjustment optical path unit, the anterior segment slit imaging adjustment optical path module adopts the anterior segment OCT imaging adjustment optical path unit, the anterior segment slit light source module adopts the anterior segment slit light source 4809, parallel optical fibers 2106 and the optical path scanning device 1109 to generate slit light, the light output by the anterior segment slit light source 4809 passes through the parallel optical fibers 2106, and the light beam output by the parallel optical fibers 2106 is scanned in one dimension by the optical path scanning device 1109 to emit slit light and pass through the anterior segment OCT imaging adjustment optical path unit to focus on the anterior segment of the person to be tested.

[0069] Further, in the second, third and fourth embodiments, the posterior segment OCT imaging adjustment optical path unit includes a posterior segment OCT field lens 1301, a front beam splitter 1303 and an eyepiece objective lens 1305; the measurement light provided by the OCT light source module is reflected by the optical path scanning device 1109 and passes through the posterior segment OCT field lens 1301, and then is reflected by the front dichroic mirror 1303 to the eyepiece objective lens 1305, and converges to the fundus of the eye of the human eye to be tested through the human eye to be tested, so as to return the posterior segment light signal to the OCT imaging module, and the OCT imaging module obtains the eye according to the posterior segment light signal. Posterior segment OCT image; the anterior segment OCT imaging adjustment optical path unit is formed by inserting the anterior segment OCT insertion mirror 1501 into the optical path formed by the posterior segment OCT imaging adjustment optical path unit. The slit light passes through the posterior segment OCT field lens 1301 and the anterior segment OCT insertion mirror 1501 in sequence, and then is reflected by the front dichroic mirror 1303 to the eye lens 1305, and converges on the anterior segment of the person to be tested, so as to return the anterior segment slit light signal to the anterior segment slit imaging module, and the anterior segment slit imaging module obtains the anterior segment slit image according to the anterior segment slit light signal.

[0070] The ophthalmic optical biometry system proposed by the present invention is further described in detail below in combination with a plurality of specific embodiments.

[0071] Embodiment 1

[0072] Embodiment 1 of the present invention discloses an ophthalmic optical biometry system, including an OCT imaging module, a posterior segment OCT sample arm module, an anterior segment OCT insertion lens, a fixation optical module, an anterior segment camera module, and an anterior segment fissure imaging module. Each module can play a corresponding function, and some optical components are shared between the modules. The modules are appropriately combined to form an ophthalmic optical biometry system.

[0073] The computer 1143 controls the entry and exit of the anterior segment OCT insertion mirror 1501, and cooperates with the translation of the fiber optic collimator 1107 along the optical axis to achieve optical path switching and OCT imaging of different parts of the human eye.

[0074] like Figure 1 As shown, it is a structural diagram of an ophthalmic optical biometry system of an embodiment 1 of the present invention, wherein the probe module 10 includes: a posterior segment OCT sample arm module, an anterior segment OCT insertion mirror, a fixation optical module, an anterior segment camera module, and an anterior segment fissure imaging module. The probe module 10 is driven as a whole by three motors (not shown in the figure), and can achieve X / Y / Z three-dimensional translation. In this embodiment, the X-axis is defined as an axis perpendicular to the paper surface, the Y-axis is defined as an axis in the up-down direction parallel to the paper surface, and the Z-axis is defined as an axis in the left-right direction parallel to the paper surface, that is, the X-axis and Y-axis directions refer to the horizontal and vertical axis directions on the plane parallel to the outer surface of the human eye E to be tested, respectively, and the Z-axis direction refers to the direction perpendicular to the plane parallel to the outer surface of the human eye E to be tested. The above definitions are only for the convenience of explanation and are not limited thereto.

[0075] (1) OCT imaging system

[0076] The OCT imaging module includes an OCT light source 1101, a fiber coupler 1103, a reference arm module 1120, a detector 1141, a computer 1143, a polarization controller 1105, and a sample arm module. The OCT light source 1101 outputs a wavelength of approximately near-infrared light, and the sample arm module includes a posterior segment OCT sample arm module and an anterior segment insertion mirror 1501. The computer 1143 in this application is not a PC in the traditional sense, but a circuit control and processing system capable of performing functions such as calculation, control, storage, and display.

[0077] The optical path of the OCT imaging module includes an OCT light source 1101 (a weak coherent light source may be used), and the light outputted by the OCT light source 1101 is provided to the sample arm module and the reference arm module 1120 through the optical fiber coupler 1103. The reference arm module 1120 has a known length, and the light provided by the optical fiber coupler 1103 to the reference arm module 1120 can be transmitted to the optical fiber coupler 1103. The sample arm module provides light to the human eye E to be tested, and the light scattered back from the human eye E to be tested is interfered in the optical fiber coupler 1103 through the sample arm module, the polarization controller 1105 and the light transmitted from the reference arm module 1120. The interference light is detected by the detector 1141, and then processed by the computer 1143, and finally the OCT image of the human eye E to be tested is displayed. Among them, the optical path scanning device 1109 adopts a two-dimensional scanning mechanism, which is composed of an X-direction scanning device 11091 and a Y-direction scanning device 11093. The sample (human eye to be tested) is scanned by the optical path scanning device 1109 to realize the tomographic imaging of OCT.

[0078] (2) Posterior segment OCT imaging system

[0079] like Figure 2 As shown, it is an optical path diagram of the posterior segment OCT imaging system. The posterior segment OCT sample arm module includes an optical path scanning device 1109 and an optical path unit for adjusting the posterior segment OCT imaging. The optical path unit for adjusting the posterior segment OCT imaging includes an optical fiber collimator 1107, an posterior segment OCT field lens 1301, a pre-beam splitter 1303, and an eye-receiving objective lens 1305. The optical path scanning device 1109 can be a one-dimensional optical path switching scanning device, or a two-dimensional or even three-dimensional optical path switching scanning device; the optical path scanning device 1109 is used to realize one-dimensional to multi-dimensional scanning of the human eye E to be measured. The optical fiber emits light through the sample arm optical fiber head (not shown in the figure), which is adjacent to the optical fiber collimator 1107; the sample arm optical fiber head and the optical fiber collimator 1107 are driven by a motor and can move along the main optical axis of the optical fiber collimator 1107, thereby changing the optical path of the sample arm optical path. Similarly, the matching of the optical paths of the sample arm and the reference arm can also be achieved by changing the optical path of the reference arm; wherein the optical fiber is connected to the optical fiber head of the sample arm.

[0080] When performing posterior segment OCT imaging, the light emitted from the fiber collimator 1107 is reflected by the optical path scanning device 1109. At this time, the optical path scanning device 1109 is controlled by the computer 1143. After the light beam is reflected by the optical path scanning device 1109, it passes through the posterior segment OCT field lens 1301, is reflected to the eye lens 1305 through the front beam splitter 1303, and finally converges to the fundus Er of the human eye to be tested through the human eye E to be tested. The detection light beam of the posterior segment OCT imaging optical path system meets the requirement that the center line of the scanning light beam converges near the pupil of the human eye, and the OCT light beam is focused on the fundus Er of the human eye at any time.

[0081] For different human eyes (with different refractive powers), the OCT beam can be converged on the human eye fundus Er by adjusting the eyepiece objective lens 1305. That is, the beam is focused on the retina, which can effectively improve the signal-to-noise ratio and lateral resolution of the OCT image during retinal measurement.

[0082] The front beam splitter 1303 can reflect the signal light emitted by the OCT light source 1101, and transmit the fixation light emitted by the fixation light source 1701 in the fixation optical module; transmit the light emitted by the anterior segment slit light source 1809 in the anterior segment slit imaging module; and can also transmit the illumination light emitted by the illumination light source 1901 in the anterior segment camera module.

[0083] At this time, the anterior segment OCT insertion mirror 1501 is controlled by the computer 1143 to switch to the posterior segment OCT imaging optical path.

[0084] When measuring the fundus, scanning is performed through the X-direction scanning device 11091 and the Y-direction scanning device 11093; the optical path matching for the fundus of different human eyes is achieved through the fiber optic collimator 1107 combined with the overall translation of the sample arm fiber optic head (not shown); the eyepiece objective lens 1305 is translated along the optical axis to adjust the refraction for different human eyes; finally, the OCT image of the posterior segment of the eye is collected, thereby obtaining important parameters of the human eye structure such as retinal thickness.

[0085] (3) Anterior Segment OCT Imaging System

[0086] like Figure 2 As shown, it is an optical path diagram of the anterior segment OCT imaging system. The posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror 1501 form an anterior segment OCT imaging adjustment optical path unit, that is, the anterior segment OCT imaging adjustment optical path unit includes a fiber collimator 1107, a posterior segment OCT field lens 1301, anterior segment OCT insertion mirror 1501, a front beam splitter 1303, and an eye-receiving objective lens 1305. Through the cooperation of the optical path scanning device 1109 and the anterior segment OCT imaging adjustment optical path unit, anterior segment OCT imaging can be performed.

[0087] When performing anterior segment OCT imaging, the light emitted from the fiber collimator 1107 is reflected by the optical path scanning device 1109, transmitted through the posterior segment OCT field lens 1301 and the anterior segment OCT insertion lens 1501, reflected by the front beam splitter 1303, and then transmitted through the eyepiece objective lens 1305, and finally converged to the anterior segment of the human eye E to be tested (i.e., the cornea of ​​the human eye to be tested). The detection beam of the anterior segment OCT imaging optical path system satisfies the OCT beam focusing on the anterior segment of the human eye.

[0088] At this time, the anterior segment OCT insertion mirror 1501 is inserted into the optical path under the control of the computer 1143 .

[0089] When measuring the anterior and posterior surfaces of the cornea and lens, the OCT beam is focused on the middle area of ​​the anterior segment of the eye, which can effectively improve the signal-to-noise ratio and lateral resolution of the OCT image when measuring the anterior and posterior surfaces of the cornea and lens.

[0090] When measuring the anterior segment OCT image, the optical path scanning device 1109 is used for scanning; the optical path matching required for OCT measurement is achieved by the fiber collimator 1107 combined with the overall translation of the sample arm optical fiber head (not shown); focusing is achieved by the translation of the eyepiece objective lens 1305 along the optical axis L1, or the overall translation of the probe module 10 along the optical axis L1. Through the cooperation of the optical path scanning device 1109 and the anterior segment OCT imaging adjustment optical path unit, OCT images of the front and back surfaces of the cornea and lens can be obtained, thereby obtaining important parameters of the human eye structure such as the front and back surface curvature of the cornea, corneal thickness, anterior chamber depth, lens thickness, and the front and back surface curvature of the lens.

[0091] (4) Anterior segment camera module

[0092] like Figure 4a and Figure 4b The figures show the front view and top view of the anterior segment camera module respectively.

[0093] This module can be used for iris preview to guide doctors to operate the instrument and align the probe light path with the eye to be tested. Or it can be used to guide the probe module 10 to automatically move in three dimensions by automatically identifying the iris center or pupil center position to achieve alignment with the pupil of the eye to be tested, thereby achieving detection of the eye to be tested.

[0094] The light emitted by the illumination light source 1901 (infrared light) irradiates the anterior chamber of the eye E to be tested, and the light is reflected by the anterior chamber tissue. The reflected light passes through the eyepiece objective lens 1305, the front beam splitter 1303, the iris injection relay lens 1903, and is transmitted through the iris injection beam splitter 1905, and then through the anterior segment camera lens 1907, and finally is photographed by the anterior segment camera device 1909.

[0095] The tester uses a chin support device (not shown) to fix the head of the testee, and lets the testee fix his eyes on the fixation mark of the system. After that, the tester controls the movement of the chin support device and the probe 10 through the operating rod while observing the display screen of the computer 1143, so that the anterior segment of the eye E of the testee enters the anterior segment camera device 1909, and the anterior segment image is presented on the display screen of the computer 1143. Alternatively, by automatically identifying the position of the iris center or the pupil center, the probe 10 is guided to automatically move in three dimensions to achieve alignment with the pupil of the test eye, thereby achieving detection of the test eye.

[0096] The anterior segment camera module 190 can be used to obtain important parameters of the human eye structure such as white-to-white distance and pupil diameter.

[0097] The distribution of the illumination light sources 1901 in the above figure is only for illustration. In other embodiments, other distribution methods may be adopted. It is only necessary for the illumination light sources 1901 to illuminate the anterior segment of the eye of the person to be tested. The number may be one or more.

[0098] The iris beam splitter 1905 transmits the illumination light from the illumination light source 1901 in the anterior segment camera module 190, reflects the fixation light from the fixation light source 1701 in the fixation optical module, and reflects the light from the anterior segment slit light source 1809 in the anterior segment slit imaging module.

[0099] (5) Anterior Segment Fissure Imaging Module

[0100] like Figure 5, which is a schematic diagram of an anterior segment slit imaging module. The anterior segment slit imaging module includes a combination module 18, a pre-beam splitter 1303, an iris injection relay lens 1903, an iris injection beam splitter 1905, an angle injection beam splitter 1807, and an anterior segment slit light source 1809, wherein the combination module 18 is composed of an eyepiece objective lens 1305, an anterior segment slit imaging lens 1801, and an anterior segment slit imaging device 1803. The combination module 18 is driven by a motor (not shown in the figure, the motor is independent of the above-mentioned three motors controlled as a whole) and can move along the Z direction to achieve refractive adjustment.

[0101] The anterior segment slit light source 1809 emits light through a knife edge or a slit to generate slit light or slit light. The slit light or slit light is reflected by the angle beam splitter 1807 and the iris beam splitter 1905, transmits the iris relay lens 1903 and the pre-beam splitter 1303, and then is focused on the anterior segment of the eye of the person to be tested through the eyepiece objective lens 1305. The anterior segment slit light passes through the anterior segment tissue, is scattered by the cornea and lens and other tissues, and the scattered light passes through the anterior segment slit imaging lens 1801 and is finally photographed by the anterior segment slit imaging device 1803.

[0102] The anterior segment slit imaging optical path (including the anterior segment slit imaging lens 1801 and the anterior segment slit imaging device 1803) is preferably distributed below the eyepiece objective lens 1305. If it is distributed on the left / right side of the X direction of the probe 10, it is not conducive to the simultaneous use of both eyes. If it is distributed above the eyepiece objective lens 1305, it is easily blocked by the eyelids.

[0103] In some embodiments, the anterior segment fissure imaging device 1803 is only used to capture the anterior segment fissure image near the corneal position of the person to be tested. The imaging range is small, but the imaging accuracy is high. Through the anterior segment fissure image, the spatial position of the cornea can be accurately located. For example, if the corneal thickness is about 550um, if the anterior segment fissure imaging range in the Z direction is between 0.5 and 10mm, the positioning accuracy of the corneal position can be effectively improved. In other embodiments, the shooting range of the anterior segment fissure imaging device 1803 is increased, and data such as the anterior chamber depth and even the lens thickness can also be obtained.

[0104] In this embodiment, the anterior segment fissure camera optical path is distributed at an oblique angle, so the anterior segment fissure imaging module combined with the anterior segment camera module can accurately identify the Z-direction position of the eye to be tested, and then combined with the collected posterior segment OCT image, the axial length of the eye to be tested can be obtained.

[0105] The angle beam splitter 1807 reflects the light emitted from the anterior segment slit light source 1809 in the anterior segment slit imaging module, and transmits the fixation light emitted from the fixation light source 1701 in the fixation optical module.

[0106] (6) Fixation Optical Module

[0107] like Figure 6 , which is a schematic diagram of the fixation optical module. The fixation light source 1701 in the fixation optical module is used as a fixation mark (internal fixation mark) for the fixation of the human eye E to be tested. The light from the fixation light source 1701 passes through the fixation optical path lens 1703 and the angle beam splitter 1807, is reflected by the iris beam splitter 1905, transmits the iris relay lens 1903 and the front beam splitter 1303, and then passes through the eye contact objective lens 1305 and is incident on the human eye E to be tested. Finally, the internal fixation mark is projected onto the fundus Er of the human eye E to be tested.

[0108] The fixation light source 1701 can be a single-point LED, or an LCD screen, an OLED screen, or an LED array screen.

[0109] When performing posterior segment OCT imaging, different eyes have different degrees of clarity when observing the fixation point, which makes the subject uncomfortable when fixating, and is not convenient for the fixation and fixation of the eye E to be tested. Since the optical path during posterior segment OCT imaging is adjusted by the eyepiece objective lens 1305, it can be focused on the fundus Er (retina of the fundus) of the eye E to be tested, that is, the human eye can see the scan line clearly. Since the posterior segment OCT imaging optical path and the fixation optical path share the eyepiece objective lens 1305, it can be achieved that different eyes can see the fixation mark clearly.

[0110] (7) Measurement of axial length

[0111] Since the detection depth of the OCT system is limited, it is impossible to achieve one-time imaging detection from the cornea to the fundus retina. Therefore, this embodiment combines the anterior segment fissure imaging and posterior segment OCT imaging technology. The position of the cornea of ​​the person to be tested is determined by anterior segment fissure imaging, and the position of the fundus of the person to be tested is determined by posterior segment OCT imaging, thereby achieving the measurement of the axial length of the eye.

[0112] like Figure 7 As shown, Er represents the fundus of the human eye to be tested, Ec represents the corneal vertex of the human eye to be tested, X represents the optical path change amount of the sample arm optical path changed by the optical path adjustment device (including the optical fiber collimator 1107 and the optical fiber head not shown in the figure) when measuring the posterior segment OCT image of the human eye to be tested; CDK represents the spatial position corresponding to the top of the anterior segment slit image; RDK1 represents the spatial position corresponding to the top of the posterior segment OCT image when the optical path adjustment device is in the reset position; RDK2 represents the spatial position corresponding to the top of the posterior segment OCT image when the optical path adjustment device changes the optical path change amount X of the sample arm optical path when measuring the posterior segment OCT image of the human eye to be tested; hCornea represents the optical path from the top of the anterior segment slit image to the corneal vertex Ec of the human eye to be tested in the anterior segment slit image; hRetinal represents the optical path from the top of the posterior segment OCT image to the retinal signal in the posterior segment OCT image. Figure 7Among the three rectangular boxes shown in the figure, the two on the left represent the OCT measurement range of the posterior segment. The rectangular boxes are only for reference, and the actual scanning area may be a fan-shaped structure. The rectangular box on the right represents the anterior segment fissure image taken by the anterior segment fissure imaging.

[0113] When shooting the anterior segment fissure image, the focusing position of the slit light generated by the anterior segment fissure light source 1809 and the spatial position or spatial range that can be photographed by the anterior segment fissure imaging optical path are determined during system debugging, that is, Figure 7 The spatial distance from the spatial position CDK corresponding to the top of the anterior segment slit image to the eyepiece objective 1305 is determined during system debugging; therefore, if the human eye to be tested moves slightly forward or backward but does not exceed the anterior segment slit imaging range, the spatial position of the cornea can be determined by identifying the position of the cornea captured in the anterior segment slit image.

[0114] When measuring the posterior segment OCT image, since the axial length of the human eye is not the same, but the length of the reference arm of the OCT system is fixed, this embodiment adopts the following methods to achieve the measurement of retina at different depths: (a) by adding an optical path adjustment device, the isointerference surface of the posterior segment OCT imaging is moved; (b) by translating the fiber collimator 1107 and the fiber head of the sample arm along the optical axis as a whole; (c) by adding a right-angle prism or a corner cube prism to make the light path turn multiple times, and then by translating the right-angle prism or the corner cube prism to achieve the change of the optical path. The above three implementation methods can be used simultaneously or one or two can be used selectively.

[0115] The OCT system finds the retinal signal of the posterior segment of the eye, and the optical path change of the optical path adjustment device relative to the reset position is X. That is, when the optical path adjustment device changes the optical path distance of the sample arm to X, the spatial position corresponding to the top of the posterior segment of the eye OCT image moves from RDK1 to RDK2, where the distance between RDK1 and RDK2 is X. Figure 7 shown.

[0116] The optical path change X of the optical path adjustment device can be measured by a variety of methods, such as driving a stepper motor or a voice coil motor to calculate the movement amount; or using a grating ruler, a capacitive grating ruler, etc. to calculate the movement amount, etc.

[0117] In addition, when the optical path adjustment device is in the reset position, the spatial distance between the spatial position RDK1 corresponding to the top of the posterior segment OCT image and the eyepiece objective lens 1305 is determined during system debugging. Therefore, the spatial distance ΔL between RDK1 (the spatial position corresponding to the top of the posterior segment OCT image) and CDK (the spatial position corresponding to the top of the anterior segment fissure image) is determined during system debugging.

[0118] Therefore, by measuring the posterior segment OCT image and the anterior segment fissure image, the axial length of the human eye Leye can be obtained:

[0119] Leye=△L+X-hCornea+hRetinal,

[0120] Where hCornea can be measured from the anterior segment fissure image, and hRetinal can be measured from the posterior segment OCT image.

[0121] Since different human eyes have different axial lengths, in order to measure the anterior and posterior segments of the human eye E to be measured, it is necessary to change the optical path of the sample arm or the reference arm to achieve OCT coherent imaging (this embodiment is explained by changing the optical path of the sample arm as an example). Changing the optical path must meet the detection depth of the OCT system and the different axial lengths of different human eyes, so precise positioning is required, so it is often difficult to achieve rapid switching to change the optical path. For example, the use of an optical path adjustment device, which relies on the translation of the motor, cannot achieve rapid switching to meet the optical path requirements for measuring the anterior and posterior segments of the human eye. Therefore, in this embodiment, the scheme of combining anterior segment fissure imaging with posterior segment OCT imaging is used to measure the axial length of the human eye to be measured.

[0122] Since the anterior segment fissure imaging and the posterior segment OCT imaging use different imaging schemes (there is no need for the OCT system to switch the optical path between the anterior and posterior segments), the two can acquire images at the same time, thus avoiding the influence of the eye movement of the person being measured and improving the measurement accuracy of the axial length.

[0123] In this embodiment, the corneal position is determined by anterior segment fissure imaging, and the fundus position is identified by posterior segment OCT imaging technology. The two can work and collect images at the same time, and there is no switching time, so the influence of eye movement can be effectively avoided, thereby obtaining more accurate axial length data. Moreover, the collection of anterior and posterior segment images in one measurement is conducive to the doctor's operation, improves the diagnosis speed, and improves the doctor-patient interaction experience. Another measurement realizes the detection of many key parameters of the human eye, such as cornea, anterior chamber depth, axial length, corneal curvature, white to white, etc. It has many advantages such as cost, speed, accuracy, and versatility.

[0124] Embodiment 2

[0125] like Figure 8As shown, the ophthalmic optical biometry system disclosed in the second embodiment of the present invention is different from the first embodiment in that the present embodiment cancels the anterior segment slit light source 1809 and the angle beam splitter 1807. In the present embodiment, the OCT light source 1101 is used to emit light through the fiber coupler 1103 and the polarization controller 1105, and then output through the fiber collimator 1107. The light beam is scanned by the optical path scanning device 1109, passes through the posterior segment OCT field lens 1301 and the anterior segment OCT insertion lens 1501, is reflected by the front beam splitter 1303, and then transmits the eye lens 1305, and finally converges to the anterior segment of the human eye to be measured. Due to the one-dimensional scanning of the optical path scanning device 1109, the slit light is formed to enter the human eye to be measured. The anterior segment slit light formed by the light source (OCT light source 1101) in the anterior segment OCT imaging system passes through the cornea, is scattered by the cornea, and the scattered light passes through the anterior segment slit imaging lens 1801, and is finally photographed by the anterior segment slit imaging device 1803, thereby forming an anterior segment slit image, such as Fig. 9 shown.

[0126] Since the axial length of the human eye is often longer than the detection depth of the OCT system, when switching from the anterior segment OCT to the posterior segment OCT, it is often necessary to simultaneously adjust the optical path length of the sample arm or reference arm of the OCT system, so that the OCT detection light incident on the anterior segment of the human eye meets the coherence length with the reference arm, or the OCT detection light incident on the posterior segment of the human eye meets the coherence length with the reference arm. Therefore, the OCT system often needs to switch to change the optical path length. As in Example 1, the fiber collimator 1107 is connected to the sample arm optical fiber, and the entirety is driven by a motor and can be translated along its optical axis, thereby changing the optical path of the sample arm optical path. However, this mode of motion to change the optical path length has a relatively slow switching speed due to the long stroke (the axial length of the human eye) and the need to match the different axial lengths of different human eyes. However, in Example 1, the simultaneous detection of the anterior segment fissure imaging and the posterior segment OCT is combined to achieve the measurement of the axial length, thereby avoiding the influence of eye movement. In the second embodiment, in order to save device costs, the anterior segment slit light source module uses an OCT light source module 1101 and an optical path scanning device 1109 to generate slit light to provide a slit illumination light source. At this time, when measuring the axial length of the eye, it is necessary to insert or withdraw the anterior segment OCT insertion mirror 1501 to realize the switching of the posterior segment OCT imaging adjustment light path unit and the anterior segment OCT imaging adjustment light path unit; but the anterior segment slit imaging is still combined with the posterior segment OCT imaging to realize the detection of the axial length of the eye, but the light source of the anterior segment slit imaging is changed to the OCT light source 1101. Therefore, when measuring the axial length of the eye in the second embodiment, there is a short switching time-the insertion of the anterior segment OCT insertion mirror 1501. However, since the insertion of the anterior segment OCT insertion mirror 1501 only requires final positioning, there is no need to move different lengths according to the axial length of different human eyes like the optical path adjustment device, so the switching speed can be increased to a very fast speed, such as switching with an electromagnet.

[0127] In this embodiment, there is no need to add an anterior segment slit light source 1809 and an angular beam splitter 1807. It is only necessary to use the original OCT light source module 1101 and the optical path scanning device 1109 to generate the anterior segment slit illumination light, and focus it on the anterior segment of the eye of the person to be measured after passing through the anterior segment OCT imaging adjustment optical path unit. Compared with the first embodiment, although the light source and other components are reduced, when switching from the posterior segment OCT to the anterior segment slit imaging, the anterior segment OCT insertion mirror 1501 needs to be inserted, and there is a little switching time. In addition, the slit light is formed by one-dimensional scanning of the optical path scanning device 1109, which also requires a little scanning time. However, since there is no need to translate the optical path adjustment device, the above time is faster than the prior art (for example, the time required for the anterior and posterior segment OCT switching process in the existing patent document 202011120798.5 includes the insertion of the anterior segment OCT insertion mirror and the time for the optical path adjustment device to change the optical path translation when measuring the anterior and posterior segments of the human eye E to be measured). It is easier to avoid the influence of eye movement when measuring the axial length.

[0128] Compared with the first embodiment, the second embodiment does not need to debug an additional optical path (the anterior segment slit illumination optical path), so the difficulty of system debugging can be reduced and the speed of system debugging can be increased.

[0129] In the second embodiment, the OCT light source 1101 is combined with the optical path of the optical path scanning device 1109 to realize the function of the anterior segment fissure light source without increasing the hardware cost.

[0130] This embodiment is different from the first embodiment except that the anterior segment slit imaging module is different. It can be understood that the fixation optical module in this embodiment no longer has an angle beam splitter 1807. Fig.10 As shown, other structures and principles are the same and will not be repeated here.

[0131] Embodiment 3

[0132] like Fig.11 As shown, the ophthalmic optical biometry system disclosed in the third embodiment of the present invention does not use the OCT light source 1101 as the anterior segment slit light source in this embodiment, compared with the second embodiment, but uses the wavelength division multiplexer 3807 to couple the detection light input from the fiber coupler 1103 to the OCT sample arm and the light output from the anterior segment slit light source 3809 to the optical fiber 1106, and then emits through the sample arm optical fiber head (not shown in the figure). In this embodiment, the anterior segment slit light source module uses the anterior segment slit light source 3809, the wavelength division multiplexer 3807, the optical fiber 1106 and the optical path scanning device 1109 to generate slit light. The light output from the anterior segment slit light source 3809 is coupled by the wavelength division multiplexer 3807 and then transmitted to the optical fiber 1106. The light beam output from the optical fiber 1106 is scanned in one dimension by the optical path scanning device 1109 to emit slit light and pass through the anterior segment OCT imaging adjustment optical path unit and then focus on the anterior segment of the person to be measured.

[0133] The optical fiber 1106 is not limited to single-mode optical fiber or multi-mode optical fiber. Fig.12 As shown, the optical fiber 1106 has a core 11061, the outer layer of the core 11061 is a cladding 11063, and the sheath 11065 wraps the cladding 11063 to protect the optical fiber.

[0134] like Fig.13 As shown, the posterior segment OCT imaging optical path in this embodiment is different from the posterior segment OCT imaging optical path in embodiment 1 only in that: the OCT light source 1101 emits light, passes through the optical fiber coupler 1103, and then passes through the polarization controller 1105, and then the detection light is transmitted to the wavelength division multiplexer 3807, and then transmitted through the optical fiber 1106 to emit light.

[0135] like Fig.14 As shown, the anterior segment OCT imaging optical path in this embodiment is different from the anterior segment OCT imaging optical path in Example 1 only in that: the OCT light source 1101 emits light, passes through the fiber coupler 1103, and then passes through the polarization controller 1105, and then the detection light is transmitted to the wavelength division multiplexer 3807, and then transmitted through the optical fiber 1106 to emit light.

[0136] like Fig.15 As shown, the anterior segment slit imaging optical path in this embodiment is compared with the anterior segment slit imaging optical path in the second embodiment. In this embodiment, the anterior segment slit light source 3809 is used to emit light, enter the optical fiber 1106 through the wavelength division multiplexer 3807, and then transmit through the optical fiber 1106, and then emit through the sample arm optical fiber head (not shown in the figure), and then output through the optical fiber collimator 1107. The light beam is scanned by the optical path scanning device 1109, passes through the posterior segment OCT field lens 1301, the anterior segment OCT insertion lens 1501, is reflected by the pre-beam splitter 1303, and then transmits the eye lens 1305, and finally converges to the anterior segment of the human eye to be tested. Due to the one-dimensional scanning of the optical path scanning device 1109, the slit light is formed to enter the human eye to be tested. The anterior segment slit light formed by the light source (OCT light source 1101 and the anterior segment slit light source 3809) in the anterior segment OCT imaging system passes through the cornea, is scattered by the cornea, and the scattered light passes through the anterior segment slit imaging lens 1801, and is finally photographed by the anterior segment slit imaging device 1803, thereby forming an anterior segment slit image.

[0137] When the ophthalmic optical biometry system of this embodiment is used to measure the axial length of the eye, as in the second embodiment, a relatively short switching scanning time is required, and no translational optical path adjustment device is required, so the switching scanning time is relatively short. In addition, the wavelength division multiplexer 3807 is used to couple the detection light input from the optical fiber coupler 1103 to the OCT sample arm and the light output from the anterior segment fissure light source 3809 to the optical fiber 1106. Compared with the second embodiment, the anterior segment fissure light source 3809 can use light sources of different wavelength bands. Since the OCT light source 1101 generally uses near-infrared light, the scattering coefficient of the anterior segment tissue of the near-infrared light is relatively small. In this embodiment, the anterior segment fissure light source 3809 can use a short-wave band to increase the scattering coefficient of the anterior segment tissue of the eye, such as a blue light band, so as to improve the imaging effect of the anterior segment fissure.

[0138] Compared with the first embodiment, this embodiment does not need to debug an additional optical path (the anterior segment slit illumination optical path), so the difficulty of system debugging can be reduced and the speed of system debugging can be improved.

[0139] Embodiment 4

[0140] like Fig.16 As shown, the ophthalmic optical biometry system disclosed in the fourth embodiment of the present invention is compared with the third embodiment. In this embodiment, the detection light input from the optical fiber coupler 1103 to the OCT sample arm and the light from the anterior segment slit light source 4809 enter the parallel optical fiber 2106, and then exit through the sample arm optical fiber head (not shown). In this implementation, the anterior segment slit light source module uses the anterior segment slit light source 4809, the parallel optical fiber 2106 and the optical path scanning device 1109 to generate slit light. The light output from the anterior segment slit light source 3809 passes through the parallel optical fiber 2106. The light beam output from the parallel optical fiber 2106 is scanned in one dimension by the optical path scanning device 1109, and then emits slit light and passes through the anterior segment OCT imaging adjustment optical path unit and then focuses on the anterior segment of the person to be measured.

[0141] like Fig.17As shown, the parallel optical fiber 2106 has an OCT optical path fiber core 21061 and an anterior segment slit illumination optical path fiber core 21062, wherein the OCT optical path fiber core 21061 is used to transmit the detection light input into the OCT sample arm from the optical fiber coupler 1103, and the OCT optical path fiber core 21061 is wrapped by the OCT optical path cladding 21063; and the anterior segment slit illumination optical path fiber core 21062 is used to transmit the light output by the anterior segment slit light source 4809, and the anterior segment slit illumination optical path fiber core 21062 is wrapped by the anterior segment slit illumination optical fiber cladding 21064; wherein the OCT optical path cladding 21063 and the anterior segment slit illumination optical fiber cladding 21064 are arranged in parallel, and are wrapped together by a sheath 21065. The parallel optical fibers 2106 share a fiber head (not shown in the figure), and the detection light of the OCT sample arm is input from the fiber coupler 1103 and the light output from the anterior segment fissure light source 4809 is transmitted. After being output from the fiber head, it enters the optical path of the OCT sample arm module. The shared fiber head forms two light sources, and the distance between the two light sources is the distance d between the OCT optical path fiber core 21061 and the anterior segment fissure illumination optical path fiber core 21062. The smaller the distance d, the better. When d is small, the parallel optical fibers 2106 share a sample arm fiber head and can emit light close to a light-emitting point. After passing through the optical path of the OCT sample arm module 130, when the light enters the human eye to be tested, the interval between the two detection points will also be smaller.

[0142] Compared with the traditional dual-core optical fiber 3106 (such as Fig.18 As shown in FIG. 1 , the fiber core 31061 / 31062 is respectively wrapped by the fiber cladding 31063 / 31064, and then wrapped by the sheath 31065 / 31066, and then the two optical fibers are wrapped by the large sheath 31069. At this time, the interval d3 between the two optical fiber cores is often large. At this time, the light emitted by the two fiber cores 31061 / 31062 cannot be approximated to be emitted from the same light emitting point. After passing through the optical path of the OCT sample arm module 130, when the light enters the human eye to be tested, the interval between the two detection points will also be large.

[0143] Therefore, the posterior segment OCT imaging optical path and the anterior segment OCT imaging optical path of this embodiment are similar to those of embodiment one or embodiment two, with the only difference being that the detection light input into the OCT sample arm from the optical fiber coupler 1103 enters the OCT optical path core 21061 in the parallel optical fiber 2106, and then exits through the sample arm optical fiber head (not shown).

[0144] like Fig.19As shown in the figure, the anterior segment slit imaging optical path in this embodiment is compared with the second embodiment. The anterior segment slit light source 4809 in this embodiment emits light into the parallel optical fiber 2106, transmits through the anterior segment slit illumination optical path fiber core 21062, and then emits light through the shared optical fiber head (not shown in the figure), and then outputs through the optical fiber collimator 1107. The light beam is scanned by the optical path scanning device 1109, passes through the posterior segment OCT field lens 1301, the anterior segment OCT insertion lens 1501, is reflected by the pre-beam splitter 1303, and then transmits the eye lens 1305, and finally converges to the anterior segment of the human eye to be tested. Due to the one-dimensional scanning of the optical path scanning device 1109, the slit light is formed to enter the human eye to be tested. The anterior segment slit light formed by the light source (OCT light source 1101) and the anterior segment slit light source 4809 in the anterior segment OCT imaging system passes through the cornea, is scattered by the cornea, and the scattered light passes through the anterior segment slit imaging lens 1801, and is finally captured by the anterior segment slit imaging device 1803, thereby forming an anterior segment slit image.

[0145] When the ophthalmic optical biometry system of this embodiment is used to measure the axial length of the eye, as in the second or third embodiment, a relatively short switching scanning time is required, and no translational optical path adjustment device is required, so the switching scanning time is relatively short. In addition, the detection light input into the OCT sample arm from the optical fiber coupler 1103 and the light output from the anterior segment fissure light source 4809 enter the parallel optical fiber 2106 in parallel. Compared with the second embodiment, the anterior segment fissure light source 4809 can use light sources of different bands. Since the OCT light source 1101 generally uses near-infrared light, the scattering coefficient of the anterior segment tissue of the near-infrared light is relatively small. In this third or fourth embodiment, the anterior segment fissure light source 3809 or the anterior segment fissure light source 4809 can use a short-wave band to increase the scattering coefficient of the anterior segment tissue of the eye, such as a blue light band, thereby improving the anterior segment fissure imaging effect.

[0146] Embodiment 5

[0147] refer to Figure 20-21 The anterior segment camera module 190 and the fixation optical module of the ophthalmic optical biometry system disclosed in the fifth embodiment of the present invention are the same as those in the second embodiment.

[0148] Posterior segment OCT sample arm module: The posterior segment OCT sample arm module includes an optical path scanning device 1109 and a posterior segment OCT imaging adjustment optical path unit; compared with Example 1 or Example 2, the light emitted from the fiber optic collimator 1107 first passes through the spectrometer 5805 and then is reflected by the optical path scanning device 1109.

[0149] Anterior segment fissure imaging: The anterior segment fissure imaging optical path adjustment module adopts the posterior segment OCT imaging optical path adjustment unit. Compared with the anterior segment fissure imaging optical path of the third and fourth embodiments, the anterior segment fissure light source module in the fifth embodiment includes an anterior segment fissure light source 5809, a lens 5807 and a beam splitter 5805. The light is emitted by the anterior segment fissure light source 5809, passes through the lens 5807, is reflected by the beam splitter 5805, and then is reflected by the optical path scanning device 1109, passes through the posterior segment OCT imaging optical path adjustment unit (passes through the posterior segment OCT field lens 1301, is reflected by the front beam splitter 1303, and then is transmitted to the eye objective lens 1305), and finally converges to the anterior segment of the human eye. Due to the one-dimensional scanning of the optical path scanning device 1109, the fissure light is incident on the eye to be tested. The anterior segment slit light formed by the anterior segment slit light source 5809 passes through the cornea, is scattered by the cornea, and the scattered light passes through the anterior segment slit imaging lens 1801, and is finally photographed by the anterior segment slit imaging device 1803, thereby forming an anterior segment slit image. The lens 5807 in this embodiment plays a similar role to the anterior segment OCT insertion lens 1501 in the previous embodiment.

[0150] The optical path for generating the anterior segment slit light of this embodiment utilizes the optical path scanning device 1109 (no need to add a scanning mechanism) to achieve scanning, thereby simplifying the generation of slit light. In this case, the degree of freedom of the arrangement of the optical path is relatively high, such as the anterior segment slit light source 1809 in the first embodiment. In other embodiments, if the optical path scanning device 1109 is not used, the anterior segment slit light source 5809 needs to emit slit light, also known as slit light. In this case, the light source needs to add a knife-edge mechanical structure to obtain a very sharp line light source.

[0151] Compared with Example 1, Example 2, Example 3 and Example 4 do not need to debug an additional optical path (anterior segment slit illumination optical path), thereby reducing the difficulty of system debugging and improving the system debugging speed.

[0152] Compared with the third embodiment, the fourth embodiment does not need to add a wavelength division multiplexer 3807, but the parallel optical fiber 2106 is not a traditional optical fiber and needs to be specially processed and manufactured.

[0153] In Embodiment 3 and Embodiment 4, the detection light of the OCT sample arm is coupled with the anterior segment fissure light or output in parallel, and then enters the optical path of the optical path scanning device 1109 and the anterior segment OCT imaging adjustment optical path unit together, so that the two optical paths can be basically parallel. This solution greatly reduces the difficulty of debugging the two optical paths.

[0154] When measuring the axial length of the eye in the fifth embodiment, the switching of the light source can be achieved by electrically controlling the light source, as in the third and fourth embodiments. Only a short scanning time is required, and no translational optical path adjustment device is required. The anterior segment fissure image and the posterior segment OCT imaging can be acquired simultaneously, so the influence of eye movement can be effectively avoided, thereby improving the real-time and accuracy of measuring the axial length of the eye.

[0155] The ophthalmic optical biometric system designed by the present invention: on the one hand, it can realize the measurement of different depths of objects, improve the detection range of the OCT system (anterior and posterior segment imaging), the switching system is stable, the positioning is accurate, and the system signal-to-noise ratio is not affected; on the other hand, it can realize the focusing of light beams at different positions, and can realize high-quality OCT imaging of different parts for human eyes with different vision, and has high lateral resolution. The anterior and posterior segment imaging OCT system can obtain many parameter data of the human eye, such as corneal curvature, corneal thickness, anterior chamber depth, lens thickness, lens surface curvature, white-to-white distance, pupil diameter, etc. Combining the anterior segment camera and automatic recognition technology can assist the automatic detection of the instrument. Through iris recognition technology, anterior segment OCT image automatic recognition technology, posterior segment OCT image automatic recognition technology and other technologies, the system can realize fully automated detection. While collecting the posterior segment OCT image, the anterior segment fissure imaging is performed to obtain accurate axial length data. The ophthalmic optical biometric system and the method for measuring axial length proposed by the present invention have the following characteristics:

[0156] (a) The optical path of the probe is required to achieve OCT imaging of different parts of the human eye to be measured, but they use different focusing positions, so the optical path used for measurement should be different. When imaging the posterior segment of the eye, the OCT beam is required to be incident on the human eye in parallel (for emmetropia); while when imaging the anterior segment of the eye, the OCT beam is required to be focused on the anterior segment of the eye. This design is conducive to improving the imaging quality of the anterior and posterior segments of the eye.

[0157] (b) When OCT imaging of the posterior segment is performed, the iso-optical path plane is located at the retina of the eye to be tested, while when OCT imaging of the anterior segment is performed, the iso-optical path plane is located at the anterior segment of the eye to be tested. There is no need to adjust the optical path of the reference arm to achieve OCT imaging of different parts.

[0158] (c) Refractive compensation can be performed for people with different vision to achieve imaging of different parts of the human eye.

[0159] (d) Able to realize the fixation optical path of the human eye to satisfy the fixation of the left and right eyes.

[0160] (e) The anterior segment camera optical path, combined with iris automatic recognition technology, can be used to direct the movement of the probe module to detect the human eye to be tested. The iris image obtained can be used to measure parameters such as pupil diameter and white-to-white distance.

[0161] (f) Fast and precise switching device to achieve rapid OCT imaging of different parts of the human eye.

[0162] (g) Based on OCT imaging of different parts of the human eye, rapid and accurate measurement of axial length, anterior chamber depth, lens thickness, etc. can be achieved without moving the reference arm.

[0163] (h) Rapid switching of front and rear sections, fewer moving mechanisms, and low cost.

[0164] (i) The fixation optical path and the posterior segment OCT share the same refractive adjustment device, which reduces the moving parts of the fixation optical path and achieves co-focality between the fixation optical path and the posterior segment OCT optical path, which is beneficial to the fixation of the tested eye and the acquisition of posterior segment OCT images.

[0165] (j) Precise positioning of the cornea is obtained by imaging the anterior segment fissure.

[0166] (k) The frequency domain optical coherence tomography technology has a faster scanning speed and higher imaging resolution than the time domain system, but the detection depth is shallow. Compared with the scanning frequency domain optical coherence tomography technology, the scanning speed and resolution are equivalent, the cost is much lower, but the detection depth is shallow.

[0167] (l) Low-cost, fast-switching scanning solution to achieve anterior and posterior segment OCT imaging. Combined with anterior segment imaging and automatic recognition technology, automatic detection of the eye to be tested is achieved. In addition, the principle is to use optical coherence tomography technology, which is theoretically not limited to frequency domain, swept frequency, or even time domain systems.

[0168] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art of the present invention, several equivalent substitutions or obvious variations can be made without departing from the concept of the present invention, and the performance or use is the same, which should be regarded as belonging to the protection scope of the present invention.

Claims

1. An optical system for measuring axial length of an eye, characterized in that: It includes an OCT light source module, an OCT imaging module, a posterior segment OCT sample arm module, and an anterior segment fissure imaging component, wherein: The OCT light source module is used to provide measurement light, and the measurement light passes through the posterior segment OCT sample arm module and then enters the fundus of the human eye to be tested, and the OCT imaging module receives the measurement light returned by the fundus of the human eye to be tested to obtain a posterior segment OCT image; The anterior segment slit imaging assembly comprises an anterior segment slit light source module, an anterior segment slit imaging module and an anterior segment slit imaging light path adjustment module, wherein the anterior segment slit light source module is used to provide slit light, and the slit light passes through the anterior segment slit imaging light path adjustment module and is focused on the anterior segment of the eye of the person to be tested, and the anterior segment slit imaging module receives the returned slit light to obtain an anterior segment slit image; The first optical path data and the second optical path data are acquired respectively by using the posterior segment OCT image and the anterior segment fissure image, and the axial length of the eye is calculated by using the first optical path data and the second optical path data.

2. The optical system according to claim 1, characterized in that The anterior segment slit imaging module comprises an anterior segment slit imaging lens (1801) and an anterior segment slit imaging device (1803). The slit light emitted by the anterior segment slit light source module is focused on the anterior segment of the eye of the person to be tested, and the returning anterior segment slit light signal passes through the anterior segment slit imaging lens (1801) and is received by the anterior segment slit imaging device (1803). The anterior segment slit imaging device (1803) obtains an anterior segment slit image based on the anterior segment slit light signal.

3. The optical system according to claim 2, characterized in that The anterior segment slit imaging adjustment optical path module comprises an eyepiece objective lens (1305), wherein the eyepiece objective lens (1305) is located on an optical path in a first direction, wherein the optical path in the first direction is perpendicular to the human eye to be tested, and the anterior segment slit imaging lens (1801) and the anterior segment slit imaging device (1803) are respectively arranged below the eyepiece objective lens (1305).

4. The optical system according to claim 1, characterized in that The anterior segment slit light source module comprises an anterior segment slit light source (1809) and a front beam splitter (1303). The anterior segment slit light source (1809) emits slit light which passes through the front beam splitter (1303) and then passes through the anterior segment slit imaging adjustment optical path module and is focused on the anterior segment of the eye of the person to be tested.

5. The optical system according to claim 1, characterized in that The posterior segment OCT sample arm module comprises an optical path scanning device (1109) and a posterior segment OCT imaging adjustment optical path unit, wherein the posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror (1501) form the anterior segment OCT imaging adjustment optical path unit, the anterior segment slit imaging adjustment optical path module adopts the anterior segment OCT imaging adjustment optical path unit, and the anterior segment slit light source module adopts the OCT light source module and the optical path scanning device (1109) to generate slit light, wherein the measurement light provided by the OCT light source module is subjected to one-dimensional scanning by the optical path scanning device (1109) to emit slit light and passes through the anterior segment OCT imaging adjustment optical path unit before being focused on the anterior segment of the eye of the person to be measured.

6. The optical system according to claim 1, characterized in that The posterior segment OCT sample arm module comprises an optical path scanning device (1109) and a posterior segment OCT imaging adjustment optical path unit. The posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror (1501) form the anterior segment OCT imaging adjustment optical path unit. The anterior segment slit imaging adjustment optical path module adopts the anterior segment OCT imaging adjustment optical path unit. The anterior segment slit light source module adopts the anterior segment slit light source (3809), a wavelength division multiplexer (3807), an optical fiber (1106) and the optical path scanning device (1109) to generate slit light. The light output by the anterior segment slit light source (3809) is coupled by the wavelength division multiplexer (3807) and then transmitted to the optical fiber (1106). The light beam output from the optical fiber (1106) is scanned in one dimension by the optical path scanning device (1109) to emit slit light and pass through the anterior segment OCT imaging adjustment optical path unit and then focus on the anterior segment of the eye of the person to be tested.

7. The optical system according to claim 1, characterized in that The posterior segment OCT sample arm module comprises an optical path scanning device (1109) and a posterior segment OCT imaging adjustment optical path unit. The posterior segment OCT imaging adjustment optical path unit and the anterior segment OCT insertion mirror (1501) form the anterior segment OCT imaging adjustment optical path unit. The anterior segment slit imaging adjustment optical path module adopts the anterior segment OCT imaging adjustment optical path unit. The anterior segment slit light source module adopts the anterior segment slit light source (4809), parallel optical fibers (2106) and the optical path scanning device (1109) to generate slit light. The light output by the anterior segment slit light source (4809) passes through the parallel optical fibers (2106). The light beam output by the parallel optical fibers (2106) is scanned in one dimension by the optical path scanning device (1109) to emit slit light and pass through the anterior segment OCT imaging adjustment optical path unit before focusing on the anterior segment of the eye of the person to be tested.

8. The optical system according to claim 1, characterized in that The posterior segment OCT sample arm module comprises an optical path scanning device (1109) and a posterior segment OCT imaging adjustment optical path unit; the anterior segment slit imaging adjustment optical path module adopts the posterior segment OCT imaging adjustment optical path unit; the anterior segment slit light source module comprises an anterior segment slit light source (5809), a lens (5807) and a beam splitter (5805); the anterior segment slit light source (5809) emits light, passes through the lens (5807), is reflected by the beam splitter (5805), and then is scanned in one dimension by the optical path scanning device (1109) to form slit light, and then passes through the anterior segment slit imaging adjustment optical path module to be focused on the anterior segment of the person to be tested.

9. The optical system according to any one of claims 5 to 8, characterized in that: The posterior segment OCT imaging adjustment optical path unit comprises a posterior segment OCT field lens (1301), a front beam splitter (1303) and an eyepiece objective lens (1305); the measurement light provided by the OCT light source module is reflected by the optical path scanning device (1109), passes through the posterior segment OCT field lens (1301), and then is reflected by the front dichroic mirror (1303) to the eyepiece objective lens (1305), and converges to the fundus of the eye of the person to be tested through the eye to be tested, so as to return a posterior segment light signal to the OCT imaging module, and the OCT imaging module obtains a posterior segment OCT image according to the posterior segment light signal; The anterior segment OCT imaging adjustment optical path unit is formed by inserting an anterior segment OCT insertion mirror (1501) into the optical path formed by the posterior segment OCT imaging adjustment optical path unit; the slit light sequentially passes through the posterior segment OCT field mirror (1301) and the anterior segment OCT insertion mirror (1501), and then is reflected by the front dichroic mirror (1303) to the eye-receiving objective lens (1305), and converges on the anterior segment of the eye of the person to be tested, so as to return an anterior segment slit light signal to the anterior segment slit imaging module; the anterior segment slit imaging module acquires an anterior segment slit image according to the anterior segment slit light signal.

10. The optical system according to claim 1, characterized in that The first optical path data refers to the optical path hRetinal from the top of the posterior segment OCT image to the retinal signal in the posterior segment OCT image measured according to the posterior segment OCT image of the human eye to be tested, and the second optical path data refers to the optical path hCornea from the top of the anterior segment fissure image to the corneal vertex of the human eye to be tested measured according to the anterior segment fissure image of the human eye to be tested; The axial length of the eye is calculated using the first optical path data and the second optical path data, including: calculating the axial length Leye of the human eye to be tested based on the optical path change X of the posterior segment OCT sample arm module when acquiring the posterior segment OCT image of the human eye to be tested and the measured optical path hRetinal and optical path hCornea.

11. A method for measuring axial length of an eye, characterized in that: Measuring the axial length of a human eye to be measured using the optical system according to any one of claims 1 to 10 comprises the following steps: Acquire the posterior segment OCT image of the human eye to be tested, and measure the optical path hRetinal from the top of the posterior segment OCT image to the retinal signal in the posterior segment OCT image according to the posterior segment OCT image of the human eye to be tested; Acquire an anterior segment fissure image of the human eye to be tested, and measure an optical path hCornea from the top of the anterior segment fissure image to the corneal vertex of the human eye to be tested according to the anterior segment fissure image of the human eye to be tested; The axial length Leye of the human eye to be tested is calculated according to the optical path change X of the posterior segment OCT sample arm module when acquiring the posterior segment OCT image of the human eye to be tested and the measured optical path hRetinal and optical path hCornea.

12. The method according to claim 11, characterized in that The axial length Leye of the human eye to be tested is calculated using the following formula: Leye=△L+X-hCornea+hRetinal; Wherein, △L represents the spatial distance between the top of the posterior segment OCT image and the top of the anterior segment fissure image, and X represents the optical path change of the posterior segment OCT sample arm module when acquiring the posterior segment OCT image of the human eye to be tested.

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