An ophthalmic measurement system with optical path compensation deflection mechanism

Abstract

An ophthalmic measurement system with an optical path compensation deflection mechanism includes an OCT light source, a reference arm, a sample arm module, an optical fiber coupler, a detector, and the optical path compensation deflection mechanism. The sample arm module contains an optical path switching scanning device that can reflect the probe light to the posterior or anterior segment of the eye. The optical path compensation deflection mechanism includes a rotation mechanism and an optical path compensation deflection component. This mechanism can dynamically adjust the optical path, maintaining a constant optical path or phase change between the A-scan and the posterior segment, simulating the Doppler frequency shift effect without increasing hardware costs. The system can avoid using loading frequency technology in the preview stage, reducing sampling requirements and lowering costs. A shallow probe depth is used during measurement for rapid alignment with the eye under test, improving accuracy. Rapid switching of scanning modes allows for accurate measurement of axial length, anterior chamber depth, and lens thickness. This invention provides a cost-effective, easy-to-operate, and accurate ophthalmic OCT imaging solution that meets clinical diagnostic needs.

Description

Technical Field

[0001] This invention relates to ophthalmic optical coherence tomography, and in particular to an ophthalmic measurement system with an optical path compensation deflection mechanism. Background Technology

[0002] The number of elderly people suffering from cataracts is increasing, and intraocular lens transplantation is currently a widely used and effective treatment for cataracts. However, the calculation of intraocular lens placement requires numerous parameters, such as the curvature of the anterior and posterior corneal surfaces, corneal thickness, anterior chamber depth, lens thickness, the curvature of the anterior and posterior lens surfaces, and axial length. These parameters are numerous, and often require testing with multiple medical devices to obtain complete data. Therefore, a medical device that can obtain all of these data in a single unit would not only improve the convenience of measurement for patients but also enhance its accuracy.

[0003] With the in-depth development of ophthalmological research, the medical community has discovered a significant correlation between myopia in adolescents and the increase in their axial length. Rapid increase in axial length during adolescent growth and development is often accompanied by a rapid progression of myopia. Therefore, studying and tracking changes in axial length growth is one of the important indicators among ophthalmological parameters in myopia prevention and control for adolescents.

[0004] Optical coherence tomography (OCT) is an emerging optical imaging technology that, compared to traditional clinical imaging methods, offers advantages such as high resolution, fast imaging speed, no radiation damage, moderate cost, and compact structure. It is an important potential tool for basic medical research and clinical diagnostic applications. Currently, among various ophthalmic devices that use optical instruments, OCT devices for ophthalmic examination and treatment have become indispensable for the diagnosis of ophthalmic diseases.

[0005] 1) Existing technologies for measuring axial length often employ time-domain tomographic scanning, which is slow and has low measurement accuracy.

[0006] Patent document 200710020707.9 discloses a method for measuring axial length of the eye using OCT. While this method can measure the axial length of the human eye and various live animals, it has two drawbacks: 1. It uses a stepper motor to move the probe to adjust the optical path, thereby achieving imaging of the cornea and fundus. However, the forward and backward movement of the motor takes time, making it impossible to achieve rapid switching between the anterior and posterior segments and real-time imaging. Furthermore, the subject's eye may shake, leading to inaccurate axial length measurements with significant errors; 2. Due to the different structures of the cornea and fundus, the same probe cannot focus at both locations, resulting in poor image quality. This is an unavoidable defect of this method.

[0007] 2) The existing patent "An OCT system and method for measuring axial length and optical path value, application number 201410214827.2" introduces corneal alignment technology, eliminating the need to switch between the anterior and posterior segments, but it lacks anterior segment measurement function and corneal curvature measurement function (or does not mention them). Measuring the cornea requires an additional operation. This prevents rapid diagnosis for patients.

[0008] 3) Existing patents “Ophthalmic Measurement System and Method, Application No. 201810130278.9” and “Ophthalmic Measurement System, Application No. 201910116857.2” make it difficult to increase the detection depth of the OCT system.

[0009] 4) The existing patent "Ophthalmic Measurement System Based on Shutter Switching, Application No. 202020735955.2" measures the anterior chamber depth and lens thickness. It also uses OCT data after two switching of the optical path to calculate the axial length. This switching speed will affect the measurement accuracy of the anterior chamber depth and lens thickness.

[0010] Compared to time-domain OCT systems, frequency-domain optical coherence tomography (OCT) offers faster scanning speed and higher imaging resolution, but shallower detection depth. Compared to frequency-domain OCT, it offers comparable scanning speed and resolution at a much lower cost, but still has a shallower detection depth.

[0011] It should be noted that the information disclosed in the background section above is only for understanding the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0012] The main objective of this invention is to overcome the deficiencies in the above-mentioned background technology and provide an ophthalmic measurement system with an optical path compensation deflection mechanism.

[0013] To achieve the above objectives, the present invention adopts the following technical solution:

[0014] An ophthalmic measurement system with an optical path compensation deflection mechanism includes an OCT imaging module. The OCT imaging module includes an OCT light source, a reference arm module, an OCT sample arm module, a fiber optic coupler, and a detector. The OCT sample arm module includes an optical path switching scanning device, a posterior segment OCT sample arm optical path, and an anterior segment OCT sample arm optical path. The probe light output from the fiber optic coupler is reflected at different angles by the optical path switching scanning device and then enters either the posterior segment OCT sample arm optical path or the anterior segment OCT sample arm optical path accordingly. The system also includes an optical path compensation deflection mechanism, which, after the probe light passes through the optical path switching scanning device... The optical path compensation deflection component enters the optical path switching scanning device. The optical path compensation deflection mechanism includes a rotation mechanism and an optical path compensation deflection component. When the rotation mechanism drives the optical path compensation deflection component to deflect to a set deflection angle, the probe light passes through the optical path compensation deflection component and deviates from the scanning center of the optical path switching scanning device, thereby introducing a Doppler frequency shift. This, in conjunction with the scanning of the optical path switching scanning device, keeps the optical path or phase change between adjacent A-Scans constant. When the optical path compensation deflection component is not deflected, the probe light passes through the optical path compensation deflection component without introducing a Doppler frequency shift.

[0015] Furthermore, the optical path compensation deflection component includes a deflection glass block and an optical path compensation glass block; wherein, when the rotation mechanism drives the optical path compensation deflection component to deflect to a set deflection angle, the probe light passes through the deflection glass block and generates a changed optical path, and the probe light does not pass through the optical path compensation glass block, while when the optical path compensation deflection component is not deflected, the probe light passes through the deflection glass block and the optical path compensation glass block.

[0016] Furthermore, the rotating mechanism is a rotary motor.

[0017] Furthermore, when the optical path compensation deflection component is not deflected, the optical path compensation deflection component is set parallel to the main optical axis of the probe light, and the probe light passes through the optical path compensation glass block and the deflection glass block at a vertical incident angle. When the optical path compensation deflection component is deflected to the set deflection angle, the main optical axis of the probe light forms an angle with the optical path compensation deflection component, and the probe light passes through the deflection glass block at an inclined angle.

[0018] Furthermore, the optical path compensation deflection component does not deflect during posterior segment and corneal OCT scanning imaging, but deflects to the set deflection angle during anterior chamber and full lens panoramic OCT scanning imaging.

[0019] Furthermore, the optical path of the anterior segment OCT sample arm includes an anterior chamber insertion lens, which is configured to cut into or out of the optical path; the anterior chamber insertion lens is designed to guide the probe beam to focus near the center of the anterior chamber during anterior chamber OCT scanning imaging; during panoramic OCT scanning imaging of the entire lens, the anterior chamber insertion lens is in the cut-out state.

[0020] Furthermore, the optical path of the anterior segment OCT sample arm includes a first reflecting mirror, a first lens, a third reflecting mirror, a fifth reflecting mirror, a third lens, a third beam splitter, a front beam splitter, and an eyepiece objective. After being reflected by the optical path switching scanning device, the light beam is successively reflected by the first reflecting mirror, transmitted through the first lens, reflected by the third reflecting mirror and the fifth reflecting mirror, transmitted through the third lens, transmitted through the third beam splitter, reflected by the front beam splitter to the eyepiece objective, and finally converged to the anterior segment of the eye by the human eye. The anterior chamber insertion lens can be inserted into the optical path of the anterior segment OCT sample arm.

[0021] Furthermore, the optical path of the posterior segment OCT sample arm sequentially includes a light path adjustment module, a posterior segment and fixation beam splitter, a refractive adjustment device, a third beam splitter, a front beam splitter, and an eye-connecting objective lens. After being reflected by the optical path switching scanning device, the light beam passes through the light path adjustment module, then through the posterior segment and fixation beam splitter, passes through the refractive adjustment device, is reflected by the third beam splitter, then by the front beam splitter to the eye-connecting objective lens, and finally converges to the fundus of the human eye.

[0022] Furthermore, it also includes a computer connected to the detector, which processes the interference signal that introduces Doppler frequency shift and uses a de-mirroring algorithm to obtain an OCT image using positive and negative frequency image data.

[0023] The present invention has the following beneficial effects:

[0024] This invention's ophthalmic measurement system innovatively incorporates an optical path compensation deflection mechanism, achieving efficient and precise imaging of different parts of the eye. Through this mechanism, the system can dynamically adjust the optical path in different imaging modes, maintaining a constant optical path or phase change between adjacent A-scans. This introduces a frequency loading technique, effectively simulating the Doppler frequency shift effect and enhancing the system's detection depth without increasing the number of spectrometer pixels or sampling points. The overall deflection of the optical path compensation deflection component achieves both frequency loading and alteration of the optical path. Compared to methods that rely on motor-driven probe movement or servo mechanisms with high-speed rotation and precise deflection positioning for frequency loading (another inventive approach), this invention avoids the use of frequency loading technology during the preview stage, reducing the need for high sampling density and effectively lowering the hardware cost of the OCT system. The system employs a shallow detection depth when measuring the cornea and retina, reducing the number of A-scans required. This not only facilitates rapid alignment of the eye and finding the working position but also improves measurement accuracy. Furthermore, this invention accelerates the switching speed between anterior and posterior segments, effectively avoiding the influence of eye movement on axial length measurement. After acquiring signals from the cornea and retina, the system can quickly switch to a panoramic OCT scanning mode for the anterior chamber and lens, enabling accurate measurement of depth and lens thickness. This design simplifies the hardware structure, reduces the requirements for the precision of the rotating motor control, while ensuring the system's detection accuracy and performance, thus improving its cost-effectiveness. This invention, through optimized optical path design and control mechanisms, provides a cost-effective, easy-to-operate, and highly accurate ophthalmic OCT imaging solution, effectively overcoming the limitations of traditional frequency domain systems in depth detection and meeting the needs of clinical diagnosis.

[0025] Other beneficial effects of the embodiments of the present invention will be further described below. Attached Figure Description

[0026] Figure 1 This is an optical path diagram of the OCT system according to an embodiment of the present invention.

[0027] Figure 2 This is an embodiment of the OCT imaging system for the posterior segment of the eye according to the present invention.

[0028] Figure 3 This is a corneal OCT scan imaging according to an embodiment of the present invention.

[0029] Figure 4 This is an embodiment of the OCT scanning imaging system for the anterior chamber of the present invention.

[0030] Figure 5 This is a panoramic OCT scanning imaging system for the entire lens, as described in this embodiment of the invention. Detailed Implementation

[0031] The embodiments of the present invention will be described in detail below. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of the present invention.

[0032] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component. Furthermore, a connection can be used for fixing, coupling, or communication.

[0033] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0034] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0035] See Figures 1 to 5This invention provides an ophthalmic measurement system with an optical path compensation deflection mechanism, including an OCT imaging module. The OCT imaging module includes an OCT light source 1101, a reference arm module, an OCT sample arm module, an optical fiber coupler 1103, and a detector 1141. The OCT sample arm module includes an optical path switching scanning device 1109, a posterior segment OCT sample arm optical path, and an anterior segment OCT sample arm optical path. The probe light output from the optical fiber coupler 1103 is reflected at different angles by the optical path switching scanning device 1109 and then enters the posterior segment OCT sample arm optical path or the anterior segment OCT sample arm optical path accordingly. The optical path also includes an optical path compensation deflection mechanism 44. After the probe light passes through the optical path compensation deflection component 440, it enters the optical path switching scanning device 1109. The optical path compensation deflection mechanism 44 includes a rotation mechanism (e.g., a rotation motor 4405) and an optical path compensation deflection component 440. The optical path compensation deflection component 440 includes a deflection glass block 4401 and an optical path compensation glass block 4403. When the rotation mechanism drives the optical path compensation deflection component 440 to deflect to a set deflection angle, the probe light is deflected by the deflection glass block 4401 and when it is incident on the optical path switching scanning device 1109, a Doppler frequency shift is introduced. Combined with the scanning of the optical path switching scanning device 1109, the optical path or phase change between adjacent A-Scans remains constant, and the probe light does not pass through the optical path compensation glass block 4403. When the optical path compensation deflection component 440 is not deflected, the probe light passes through the deflection glass block 4401 and the optical path compensation glass block 4403, without introducing Doppler frequency shift.

[0036] like Figures 1 to 5 As shown, in a preferred embodiment, when the optical path compensation deflection component 440 is not deflected, the optical path compensation deflection component 440 is arranged parallel to the main optical axis of the probe light, and the probe light passes through the optical path compensation glass block 4403 and the deflection glass block 4401 at a perpendicular incident angle. When the optical path compensation deflection component 440 is deflected to the set deflection angle, the main optical axis of the probe light forms an angle with the optical path compensation deflection component 440, and the probe light passes through the deflection glass block 4401 at an inclined angle.

[0037] In a preferred embodiment, the optical path compensation deflection component 440 does not deflect during posterior segment and corneal OCT scanning imaging (see [link]). Figure 2 and Figure 3 The optical path compensation deflection component 440 deflects to the set deflection angle when performing panoramic OCT scanning imaging of the anterior chamber and the entire lens (see...). Figure 4 and Figure 5 ).

[0038] This invention's ophthalmic measurement system achieves efficient and precise imaging of different parts of the eye by introducing an optical path compensation deflection mechanism. The system can rapidly switch between anterior and posterior segment OCT imaging, improving the detection range of the OCT system while maintaining its stability and accurate positioning capabilities without affecting the signal-to-noise ratio. The optical path compensation deflection mechanism allows the beam to be focused at different positions, providing high-quality imaging for eyes with varying vision and high lateral resolution. The system can acquire numerous human eye parameters, including corneal curvature, corneal thickness, anterior chamber depth, and lens thickness, and can focus separately on tissues at different depths, such as the anterior chamber, lens, and retina, improving the signal-to-noise ratio and resolution of OCT detection. Furthermore, through innovative optical path design and control mechanisms, combined with Doppler frequency shift technology, the system deepens its detection depth while maintaining constant detection resolution, effectively overcoming the limitations of traditional frequency domain systems in terms of detection depth. This design not only improves imaging speed and accuracy but also enhances the system's versatility, enabling it to meet the diverse needs of clinical diagnosis. In summary, this invention provides a cost-effective, easy-to-operate, and accurate ophthalmic OCT imaging solution by optimizing the optical path design and control mechanism, thus meeting the high standards required for the diagnosis of ophthalmic diseases.

[0039] The ophthalmic measurement system of this invention achieves both frequency loading and optical path modification through the overall deflection of the optical path compensation deflection component. Compared to methods that rely on motor-driven probe movement or servo mechanisms with high-speed rotation and precise deflection positioning to achieve frequency loading, this invention avoids the use of frequency loading technology during the preview stage, reducing the need for high sampling density and effectively lowering the hardware cost of the OCT system. The system employs a shallow detection depth when measuring the cornea and retina, reducing the number of A-scans required. This not only facilitates rapid alignment of the eye and finding the working position but also improves measurement accuracy. Furthermore, this invention accelerates the switching speed between anterior and posterior segment scans, effectively avoiding the influence of eye movement on axial length measurement. After completing corneal and retinal signal acquisition, the system can quickly switch to a panoramic OCT scanning mode for the anterior chamber and lens, achieving accurate measurement of anterior chamber depth and lens thickness. This design simplifies the hardware structure, reduces the requirements for the control precision of the rotating motor, while ensuring the system's detection accuracy and performance, thus improving the system's cost-effectiveness.

[0040] The following describes specific embodiments of the present invention.

[0041] Figure 1 The diagram shown is an optical path diagram of an OCT system according to a specific embodiment.

[0042] Posterior segment OCT sample arm module

[0043] The posterior segment OCT imaging system of the embodiment is as follows: Figure 2 As shown.

[0044] The posterior segment sample arm module includes an optical path switching scanning device 1109, an optical path adjustment module 1301, a posterior segment and fixation beam splitter 1303 (first beam splitter 1303), a refractive adjustment device 1305, a third beam splitter 1307, a front beam splitter 1309 (fifth beam splitter 1309), and an eyepiece objective lens 1311. In this embodiment, the posterior segment sample arm module also includes an optical path compensation deflection mechanism 44. The optical path compensation deflection mechanism 44 is composed of a rotating motor 4405 and an optical path compensation deflection assembly 440. The optical path compensation deflection assembly 440 is composed of a deflection glass block 4401 and an optical path compensation glass block 4403.

[0045] During posterior segment OCT imaging, light emitted from collimating lens 1107 passes through optical path compensation deflection component 440 and is reflected by optical path switching scanning device 1109. At this time, optical path switching scanning device 1109 is controlled by computer 1143. After reflection by optical path switching scanning device 1109, the beam passes through optical path adjustment module 1301, then through the posterior segment and fixation beam splitter 1303 (first beam splitter 1303), passes through refractive adjustment device 1305, is reflected by third beam splitter 1307, then by front beam splitter 1309 (fifth beam splitter 1309), and finally converges to the fundus Er of the human eye. The detection beam of the posterior segment OCT imaging optical path system satisfies the condition that the center line of the scanning beam converges near the pupil of the human eye, and the OCT beam is focused on the fundus Er of the human eye at any given time.

[0046] The optical path compensation deflection assembly 440 is controlled by a rotating motor 4405 to be positioned parallel to the main optical axis L44. At this time, the OCT scanning probe light from the posterior segment of the eye passes through the deflection glass block 4401 and the optical path compensation glass block 4403.

[0047] Anterior segment OCT sample arm module

[0048] The anterior segment sample arm module includes an optical path switching scanning device 1109, a first reflecting mirror 1501, a first lens 1503, a third reflecting mirror 1505, a fifth reflecting mirror 1507, a third lens 1509, a third beam splitter 1307, a front beam splitter 1309 (fifth beam splitter 1309), and an eyepiece objective lens 1311. The anterior segment sample arm module also includes a measuring anterior chamber insertion lens 3601 and an optical path compensation deflection mechanism 44.

[0049] In this embodiment, the anterior segment OCT sample arm module can be used for corneal OCT scanning imaging, panoramic OCT scanning imaging of the entire lens, and anterior chamber OCT scanning imaging.

[0050] Corneal OCT scan imaging

[0051] The corneal OCT scan imaging of the embodiment is as follows Figure 3 As shown.

[0052] During corneal OCT scanning imaging, the light emitted from the collimating lens 1107 passes through the optical path compensation deflection assembly 440 and is reflected by the optical path switching scanning device 1109. At this time, the optical path switching scanning device 1109 is controlled by the computer 1143. After being reflected by the optical path switching scanning device 1109, the light beam is successively reflected by the first reflecting mirror 1501, transmitted through the first lens 1503, reflected by the third reflecting mirror 1505, passes through the anterior chamber insertion lens 3601, reflected by the fifth reflecting mirror 1507, transmitted through the third lens 1509, transmitted through the third beam splitter 1307, and then reflected by the front beam splitter 1309 (the fifth beam splitter 1309) to the eyepiece objective lens 1311. Finally, it converges to the cornea of ​​the human eye E. The detection beam of the anterior segment OCT imaging optical path system satisfies the requirement that the OCT beam is focused on the human cornea.

[0053] The optical path switching scanning device 1109 is controlled by the computer 1143 and is positioned to achieve anterior segment OCT imaging. At this time, the position of the optical path switching scanning device 1109 is such that the angle between the principal axis of the incident light from the collimating lens 1107 and the principal axis of the reflected light is β.

[0054] In this embodiment, the anterior segment OCT sample arm module is primarily used for corneal OCT scanning imaging. At this time, the insertion lens of the anterior segment OCT imaging shutter device—the anterior chamber measuring insertion lens 3601—is inserted into the anterior segment OCT optical path. That is, during corneal OCT scanning imaging, the probe light passes through the insertion lens of the shutter device.

[0055] The optical path compensation deflection component 440 is controlled by a rotating motor 4405 to be positioned parallel to the main optical axis L44. At this time, the anterior segment OCT scanning probe light passes through the deflection glass block 4401 and the optical path compensation glass block 4403.

[0056] OCT imaging of the anterior chamber

[0057] The anterior chamber OCT scanning imaging system of the embodiment is as follows Figure 4 As shown.

[0058] When performing anterior chamber OCT scanning imaging, the optical path of the anterior segment OCT sample arm also includes an optical path switching scanning device 1109, a first reflecting mirror 1501, a first lens 1503, a third reflecting mirror 1505, an anterior chamber insertion mirror 3601 of the shutter device, a fifth reflecting mirror 1507, a third lens 1509, a third beam splitter 1307, a front beam splitter 1309 (fifth beam splitter 1309), an eyepiece objective lens 1311, and an optical path compensation deflection mechanism 44.

[0059] During anterior chamber OCT scanning imaging, light emitted from collimating lens 1107 passes through optical path compensation deflection assembly 440. Optical path compensation deflection assembly 440 is controlled by rotating motor 4405, deflecting it at a specific angle relative to the principal optical axis L44. This deflection angle causes optical path compensation glass block 4403 to deflect out of the anterior chamber OCT probe optical path, and causes deflection glass block 4401 to rotate to this deflection angle. This deflection angle ensures that the optical path or phase change between adjacent A-scans remains constant during anterior chamber OCT scanning imaging, which is necessary for subsequent use by computer 1143 using the Doppler image removal algorithm. This deflection angle is related to optical path parameters, the number of A-scans, and their speed. Next, the anterior chamber OCT probe light is reflected by optical path switching scanning device 1109, which is controlled by computer 1143. After being reflected by the optical path switching scanning device 1109, the light beam is successively reflected by the first reflecting mirror 1501, transmitted through the first lens 1503, reflected by the third reflecting mirror 1505, transmitted through the anterior chamber insertion mirror 3601, reflected by the fifth reflecting mirror 1507, transmitted through the third lens 1509, transmitted through the third beam splitter 1307, and then reflected by the front beam splitter 1309 (the fifth beam splitter 1309) to the eyepiece objective lens 1311. Finally, it converges near the center of the anterior chamber of the eye through the human eye E. The detection beam of the anterior chamber OCT scanning imaging optical path system satisfies the requirement that the OCT beam is focused near the center of the anterior chamber of the eye.

[0060] At this time, the anterior chamber insertion lens 3601 of the shutter device is inserted into the anterior segment OCT optical path. That is, during anterior chamber OCT scanning and imaging, the probe light passes through the anterior chamber insertion lens 3601, but the optical path compensation deflection component 440 needs to be deflected at a specific angle. The optical path compensation glass block 4403 deflects the light out of the optical path to meet the optical path matching requirements during anterior chamber OCT.

[0061] Panoramic OCT imaging of the entire lens

[0062] The embodiment of the whole lens panoramic OCT scanning imaging system is as follows: Figure 5 As shown.

[0063] During a full-lens panoramic OCT scan, light emitted from the collimating lens 1107 passes through the optical path compensation deflection assembly 440. This assembly, controlled by a rotation motor 4405, is deflected at a specific angle relative to the principal optical axis L44. This deflection angle causes the optical path compensation glass block 4403 to deflect out of the anterior chamber OCT detection optical path, and the deflection glass block 4401 to rotate to this angle. This deflection angle ensures that the optical path or phase change between adjacent A-scans remains constant during anterior chamber OCT scanning, facilitating subsequent use by the computer 1143 using the Doppler image removal algorithm. This deflection angle is related to optical path parameters, the number of A-scans, and their speed. Next, the anterior chamber OCT probe light is reflected by the optical path switching scanning device 1109, which is controlled by the computer 1143. After being reflected by the optical path switching scanning device 1109, the beam is successively reflected by the first reflecting mirror 1501, transmitted through the first lens 1503, reflected by the third reflecting mirror 1505 and the fifth reflecting mirror 1507, transmitted through the third lens 1509, transmitted through the third beam splitter 1307, and then reflected by the front beam splitter 1309 (the fifth beam splitter 1309) to the eyepiece objective lens 1311. Finally, it is converged by the human eye E onto the lens of the human eye. The probe beam of the anterior segment OCT imaging optical path system satisfies the requirement that the OCT beam is focused onto the lens of the human eye.

[0064] The optical path switching scanning device 1109 is controlled by the computer 1143 and is positioned to achieve anterior segment OCT imaging. At this time, the position of the optical path switching scanning device 1109 is such that the angle between the principal axis of the incident light from the collimating lens 1107 and the principal axis of the reflected light is β.

[0065] At this point, the insertion lens of the OCT imaging shutter device for different depths of the anterior segment—the anterior chamber insertion lens 3601—is in a state away from the anterior segment OCT optical path. That is, when measuring the entire lens in a panoramic OCT scan, the probe light does not pass through the insertion lens of the shutter device, but the optical path compensation deflection component 440 still maintains a specific deflection angle. Furthermore, the anterior chamber insertion lens 3601 not only adjusts the optical path but also changes the focusing position of the anterior segment OCT sample arm optical path. Its insertion position is only shown in the diagram; in principle, it can be inserted into other positions within the anterior segment OCT sample arm optical path.

[0066] In summary, this invention provides an ophthalmic measurement system that achieves efficient and accurate imaging of different parts of the eye by introducing an optical path compensation deflection mechanism. In contrast, other methods conceived by the inventors to increase the detection depth of an OCT system using Doppler frequency shift technology dynamically adjust the optical path and maintain a constant optical path change between adjacent OCT scans. These methods achieve deeper detection from the cornea to the posterior surface of the lens, but require increasing the number of spectrometer pixels or sampling points, thus increasing hardware costs. Furthermore, to synthesize a single-frame OCT image, these methods require acquiring more A-scans, which not only increases the system's acquisition speed requirements but may also lead to stuttering and eye-motion artifacts during real-time preview and rapid scan switching.

[0067] In contrast, this invention does not introduce loading frequency technology in the preview stage. Instead, it utilizes an optical path compensation deflection mechanism to employ a shallow detection depth when measuring the cornea (tissue thickness approximately 0.5 mm) and retina, reducing the number of A-scans required and thus lowering the sampling density requirements and hardware costs. This invention also accelerates the switching speed between anterior and posterior segments, effectively avoiding the influence of eye movements on the measurement, and allows for rapid switching to other scanning modes after corneal and retinal signal acquisition, achieving accurate measurement of depth and lens thickness. This design simplifies the hardware structure and reduces the requirements for the precision of the rotating motor control, requiring only mechanical limiters. The required OCT system has a shallower detection depth and a relatively lower acquisition rate. Simultaneously, it ensures the system's detection accuracy and performance, improving its cost-effectiveness. In summary, this invention, through optimized optical path design and control mechanisms, provides a cost-effective, easy-to-operate, and accurate ophthalmic OCT imaging solution.

[0068] The above description provides a further detailed explanation of the present invention in conjunction with specific / preferred embodiments, and it should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the scope of protection of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific features, structures, materials, or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions, and modifications can be made herein without departing from the scope of protection of the patent application.

Claims

1. An ophthalmic measurement system with an optical path compensation deflection mechanism, comprising an OCT imaging module, wherein the OCT imaging module includes an OCT light source, a reference arm module, an OCT sample arm module, an optical fiber coupler, and a detector, and the OCT sample arm module includes an optical path switching scanning device, a posterior segment OCT sample arm optical path, and an anterior segment OCT sample arm optical path, wherein the probe light output from the optical fiber coupler is reflected at different angles by the optical path switching scanning device and then enters the posterior segment OCT sample arm optical path or the anterior segment OCT sample arm optical path accordingly; characterized in that, It also includes an optical path compensation deflection mechanism. After the probe light passes through the optical path compensation deflection component, it enters the optical path switching scanning device. The optical path compensation deflection mechanism includes a rotation mechanism and an optical path compensation deflection component. When the rotation mechanism drives the optical path compensation deflection component to deflect to a set deflection angle, the probe light passes through the optical path compensation deflection component and deviates from the scanning center of the optical path switching scanning device, thereby introducing a Doppler frequency shift. In conjunction with the scanning of the optical path switching scanning device, the optical path or phase change between adjacent A-Scans remains constant. When the optical path compensation deflection component is not deflected, the probe light passes through the optical path compensation deflection component without introducing a Doppler frequency shift.

2. The ophthalmic measurement system as described in claim 1, characterized in that, The optical path compensation deflection component includes a deflection glass block and an optical path compensation glass block; wherein, when the rotation mechanism drives the optical path compensation deflection component to deflect to a set deflection angle, the probe light passes through the deflection glass block and generates a changed optical path, and the probe light does not pass through the optical path compensation glass block, while when the optical path compensation deflection component is not deflected, the probe light passes through the deflection glass block and the optical path compensation glass block.

3. The ophthalmic measurement system as described in claim 1, characterized in that, The rotating mechanism is a rotary motor.

4. The ophthalmic measurement system as described in claim 2, characterized in that, When the optical path compensation deflection component is not deflected, it is set parallel to the main optical axis of the probe light. The probe light passes through the optical path compensation glass block and the deflection glass block at a perpendicular incident angle. When the optical path compensation deflection component deflects to the set deflection angle, the main optical axis of the probe light forms an angle with the optical path compensation deflection component, and the probe light passes through the deflection glass block at an inclined angle.

5. The ophthalmic measurement system according to any one of claims 1 to 4, characterized in that, The optical path compensation deflection component does not deflect during OCT scanning imaging of the posterior segment and cornea, but deflects to the set deflection angle during panoramic OCT scanning imaging of the anterior chamber and the entire lens.

6. The ophthalmic measurement system according to any one of claims 1 to 5, characterized in that, The optical path of the anterior segment OCT sample arm includes an anterior chamber insertion lens, which is configured to cut into or out of the optical path; the anterior chamber insertion lens is designed to guide the probe beam to focus near the center of the anterior chamber during anterior chamber OCT scanning imaging; during panoramic OCT scanning imaging of the entire lens, the anterior chamber insertion lens is in the cut-out state.

7. The ophthalmic measurement system as described in claim 6, characterized in that, The optical path of the anterior segment OCT sample arm includes a first reflecting mirror, a first lens, a third reflecting mirror, a fifth reflecting mirror, a third lens, a third beam splitter, a front beam splitter, and an eyepiece objective. After being reflected by the optical path switching scanning device, the light beam is successively reflected by the first reflecting mirror, transmitted through the first lens, reflected by the third reflecting mirror and the fifth reflecting mirror, transmitted through the third lens, transmitted through the third beam splitter, reflected by the front beam splitter to the eyepiece objective, and finally converged to the anterior segment of the eye by the human eye. The anterior chamber insertion mirror can be inserted into the optical path of the anterior segment OCT sample arm.

8. The ophthalmic measurement system according to any one of claims 1 to 7, characterized in that, The optical path of the posterior segment OCT sample arm includes, in sequence, a light path adjustment module, a posterior segment and fixation beam splitter, a refractive adjustment device, a third beam splitter, a front beam splitter, and an eye-connecting objective lens. After being reflected by the optical path switching scanning device, the light beam passes through the light path adjustment module, then through the posterior segment and fixation beam splitter, passes through the refractive adjustment device, is reflected by the third beam splitter, then by the front beam splitter to the eye-connecting objective lens, and finally converges to the fundus of the human eye.

9. The ophthalmic measurement system according to any one of claims 1 to 8, characterized in that, It also includes a computer connected to the detector, which processes the interference signal that introduces Doppler frequency shift and uses a de-mirroring algorithm to obtain an OCT image using positive and negative frequency image data.

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