Handheld full-eye OCT (optical coherence tomography) device for realizing wide-area imaging

Abstract

The invention belongs to the technical field of full-eye imaging medical equipment, and particularly relates to a handheld full-eye OCT (optical coherence tomography) device for realizing wide-area imaging, which comprises an imaging system, a control system, a reference arm module and a sample arm module, the sample arm module comprises a galvanometer module and a switching module which are sequentially arranged on an output light path of the optical fiber interference module; the switching module comprises a third achromatic doublet lens group, an overturning mirror structure and a fourth achromatic doublet lens group which are sequentially arranged on an output light path of the galvanometer module, and the third achromatic doublet lens group and the fourth achromatic doublet lens group form a telescope system; and the switching module is used for switching different imaging parts through the overturning mirror structure. Compared with the prior art, the problems that in the prior art, single imaging is mostly used for anterior segment or posterior segment of the eye, the visual field is small, the whole posterior segment of the eye is difficult to fully cover, and the visual field is limited in the traditional fundus photography technology are solved; according to the scheme, the imaging positions of the anterior segment and the posterior segment can be switched, and meanwhile wide-angle imaging of a large view field can be achieved at the posterior segment of the eye.

Description

Technical Field

[0001] The present invention belongs to the technical field of whole-eye imaging medical equipment, and in particular relates to a handheld whole-eye OCT device for realizing wide-area imaging. Background Art

[0002] The eye is one of the most valuable organs in the human body and plays an indispensable role in our daily life. As such, eye diseases and vision loss are serious problems. Imaging examinations involving the entire eye are an important means of ophthalmological diagnosis.

[0003] Optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) have been regarded as the gold standard for the diagnosis of ophthalmic diseases in recent years. They have rapidly developed into indispensable diagnostic tools for ophthalmology due to their advantages of in vivo, non-invasive, real-time, high-resolution and three-dimensional tomography. Among them, handheld OCT has been widely used in ophthalmology and other medical fields due to its portability and operational flexibility.

[0004] Existing handheld OCT devices are mostly used for imaging the anterior segment of the eye (such as the cornea and anterior chamber) or the posterior segment of the eye (such as the retina and choroid), but most systems have difficulty in simultaneously achieving wide-angle scanning and comprehensive coverage of the anterior and posterior segments. Traditional handheld OCT devices have a limited field of view and are difficult to provide comprehensive information on the structure and function of the eye, which limits early disease diagnosis and evaluation of treatment effects.

[0005] For example, the whole-eye optical coherence tomography imager disclosed in CN103815868A includes: a frequency-sweeping light source, a fiber polarizer, a first and a second optical circulator, a first and a second broadband polarization beam splitter prism in the sample arm module, an anterior segment scanning imaging optical path and a fundus scanning imaging optical path, a third broadband polarization beam splitter prism and two reference mirrors in the reference arm module, a fourth and a fifth broadband polarization beam splitter prism, a second and a third polarization-maintaining optical coupler, a first and a second balanced detector at the detection end, and a function generator card, a data acquisition card, and a computer. However, 1) the system uses a polarization beam splitter prism, which increases the difficulty of debugging and operating the system; 2) in the spectroscopic system, light is divided into different polarization components, which leads to a weakening of the light intensity in each polarization direction (usually the light intensity in each polarization direction is halved); 3) the spectroscopic system needs to process polarization-related signals, and requires additional data processing to analyze light in different polarization states, which increases the computational burden of the system and reduces the speed of signal acquisition and processing.

[0006] For example, CN113520298A discloses an integrated optical coherence tomography structure / function imaging system for the anterior and posterior segments, including a swept-frequency laser light source, a fiber coupler, a circulator, a polarization controller, a control system, a reference arm module, and a sample arm module. The sample arm module includes an anterior segment structure / function imaging system and a posterior segment structure / function imaging system, which can realize OCT / OCTA imaging of different parts of the whole eye, and switch between different imaging parts through a flip mirror device. Although the anterior and posterior segment OCT systems of this solution can provide structural and functional imaging, they cannot simultaneously realize wide-area imaging of the anterior and posterior segments, and two mirrors need to be flipped at the sample arm, which increases the difficulty of operation and makes it difficult to ensure accuracy.

[0007] Therefore, it is necessary to propose a whole-eye OCT device that can achieve wide-area imaging. Summary of the invention

[0008] The purpose of the present invention is to provide a handheld whole-eye OCT device that realizes wide-area imaging in order to solve at least one of the above problems, so as to solve the problem that the existing technology is mostly used for single imaging of the anterior or posterior segment, and the field of view is small, and it is difficult to fully cover the entire posterior segment of the eye. The traditional fundus photography technology also has the problem of limited field of view, which makes it difficult to provide comprehensive eye structure and function information, especially the requirement of wide-angle scanning in the posterior segment of the eye, which has brought limitations to early disease diagnosis and treatment effect evaluation; this solution can realize the wide-angle imaging of the posterior segment of the eye by simply switching the anterior and posterior segment imaging positions of the OCT / OCTA imaging system at any time. In addition to solving the problem of vignetting artifacts during imaging, it also has the advantage of easy system operation.

[0009] The purpose of the present invention is achieved through the following technical solutions:

[0010] A handheld whole-eye OCT device for realizing wide-area imaging, used for performing whole-eye OCT and OCTA on an eyeball to be tested, comprising an imaging system, a control system, a reference arm module and a sample arm module;

[0011] The imaging system comprises a frequency-sweeping laser light source, a fiber-optic interferometer module and a photoelectric balance detector; the fiber-optic interferometer module is arranged on the output light path of the frequency-sweeping laser light source, and the fiber-optic interferometer module has a plurality of output light paths, and the photoelectric balance detector, the reference arm module and the sample arm module are respectively arranged on different output light paths of the fiber-optic interferometer module;

[0012] The sample arm module comprises a galvanometer module and a switching module which are sequentially arranged on the output optical path of the optical fiber interference module; the switching module comprises a third achromatic doublet lens group, a flip mirror structure and a fourth achromatic doublet lens group which are sequentially arranged on the output optical path of the galvanometer module, wherein the third achromatic doublet lens group and the fourth achromatic doublet lens group constitute a telescope system for implementing wide-angle scanning in the posterior segment of the eye; the switching module implements switching between different imaging parts of the eyeball to be measured through the flip mirror structure;

[0013] The eyeball to be tested is located on the output light path of the sample arm module;

[0014] The control system is electrically connected to the frequency-sweeping laser light source, the photoelectric balance detector and the galvanometer module respectively.

[0015] Preferably, the flip mirror structure comprises a sixth reflector, a seventh reflector, an eighth reflector, a ninth reflector and an achromatic doublet lens which are sequentially arranged on the output light path of the third achromatic doublet lens group, and the sixth reflector is also on the output light path of the achromatic doublet lens;

[0016] The sixth reflecting mirror reflects the output light path of the third achromatic doublet lens group to the fourth achromatic doublet lens group or the seventh reflecting mirror, so as to switch different imaging parts of the eyeball to be measured.

[0017] Preferably, when the sixth reflector reflects the output light path of the third achromatic doublet lens group to the fourth achromatic doublet lens group, it is a posterior segment imaging mode, and the distance between the lenses matches the focal length of the lenses;

[0018] When the sixth reflecting mirror reflects the output light path of the third achromatic doublet lens group to the seventh reflecting mirror, it is an anterior segment imaging mode, and the distance between the lenses is equal to the sum of the focal lengths of the lenses.

[0019] Preferably, the focal length f1 of the third achromatic doublet lens group is greater than the focal length f3 of the fourth achromatic doublet lens group.

[0020] Preferably, the galvanometer module comprises a first galvanometer, a first achromatic doublet lens group, a second achromatic doublet lens group and a second galvanometer, which are sequentially arranged on the output light path of the optical fiber interference module;

[0021] The control system is electrically connected to the first galvanometer and the second galvanometer respectively.

[0022] Preferably, the first achromatic doublet lens group and the second achromatic doublet lens group form a 4F system.

[0023] Preferably, the sample arm module further comprises a second beam expansion collimator and an electric focusing lens;

[0024] The second beam expansion collimator and the electric focusing lens are sequentially arranged on the optical path between the optical fiber interference module and the galvanometer module.

[0025] Preferably, the reference arm module comprises a first beam expansion collimator, a first reflector, a second reflector, a third reflector, a fourth reflector and a fifth reflector which are sequentially arranged on the output light path of the optical fiber interference module;

[0026] The reference arm module satisfies that: the reflected light path coincides with the incident light path.

[0027] Preferably, the fiber interference module comprises a first fiber coupler, a second fiber coupler, a first circulator, a second circulator, a first polarization controller and a second polarization controller;

[0028] The first circulator is connected to the first fiber coupler, the second fiber coupler and the first polarization controller through optical fibers respectively; the reference arm module is located on the output optical path of the first polarization controller;

[0029] The second circulator is connected to the first fiber coupler, the second fiber coupler and the second polarization controller through optical fibers respectively; the sample arm module is located on the output optical path of the second polarization controller;

[0030] The second optical fiber coupler is connected to the photoelectric balance detector via an optical fiber.

[0031] Preferably, the control system includes a high-speed acquisition card and a signal acquisition card;

[0032] The high-speed acquisition card is electrically connected to the frequency-sweeping laser light source, the photoelectric balance detector and the signal acquisition card respectively;

[0033] The signal acquisition card is electrically connected to the galvanometer module.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] In the present invention, considering the need for imaging the anterior segment of the eye and the retina and choroid at large angles, the optical path is designed to focus the sample light in front of the lens and the rear end of the retina through optical conversion. In order to achieve the requirement of wide-angle scanning in the posterior segment of the eye, a telescope system is used at the sample arm module to increase the scanning angle, and a 4F system is used in the scanning module to eliminate vignetting artifacts, and the device is simple and easy to operate. In addition, the non-spectral system in this solution concentrates the intensity of all light on one detection channel, which can obtain higher signal intensity and better signal-to-noise ratio.

[0036] The structure of the switching module for switching the anterior segment imaging mode is arranged in a ring, which enhances the compactness of the structure and enables it to be better handheld. This solution can also simultaneously achieve wide-area imaging of the anterior and posterior segments, and only one reflector needs to be flipped at the sample arm, which has a simpler structure, easier operation, and higher accuracy.

[0037] The optical path design of the sample arm in this solution reduces the heavy structure in traditional optical devices by using simplified optical elements, such as liquid lenses and lightweight collimating mirrors. The liquid lens can achieve focusing through electronic control without the need for a large mechanical structure, which greatly reduces the overall weight of the sample arm and makes it suitable for handheld operation. Therefore, the volume and weight of the handheld end (sample arm module) in the device of the present invention are small, and ultimately the construction of a handheld OCT device can be realized.

[0038] In summary, this solution can realize handheld and wide-area imaging at the same time, while the existing technology cannot realize handheld and wide-area imaging at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the structure of a handheld whole-eye OCT device;

[0040] Figure 2 It is a structural schematic diagram of the galvanometer module;

[0041] Figure 3 It is a schematic diagram of the structure and optical path of the switching module in the anterior segment imaging mode;

[0042] Figure 4 This is a schematic diagram of the optical path of the switching module in the posterior segment imaging mode;

[0043] Figure 5 It is a schematic diagram of the structure and optical path of the switching module in the posterior segment imaging mode;

[0044] Figure 6 The spot diagram of the switching module in the posterior segment imaging mode;

[0045] In the figure:

[0046] 1. Frequency-sweeping laser light source;

[0047] 2. A first optical fiber coupler;

[0048] 3. A second optical fiber coupler;

[0049] 4. The first circulator;

[0050] 5. Second circulator;

[0051] 6. A first polarization controller;

[0052] 7. A second polarization controller;

[0053] 8. Photoelectric balance detector;

[0054] 9. High-speed acquisition card;

[0055] 10. Signal acquisition card;

[0056] 11. The first reflector:

[0057] 12. A second reflector;

[0058] 13. The third reflector;

[0059] 14. The fourth reflector;

[0060] 15. Fifth reflector;

[0061] 16. Sixth reflector;

[0062] A. Fiber optic interferometer module;

[0063] B. Reference arm module;

[0064] C. Sample arm module;

[0065] D. Switching module;

[0066] E. Galvanometer module

[0067] L1, the first beam expansion collimator;

[0068] L2, second beam expansion collimator;

[0069] L3, electric focus lens;

[0070] L4, the first achromatic doublet lens group;

[0071] L5, the second achromatic doublet lens group;

[0072] L6, the third achromatic doublet lens group;

[0073] L7, achromatic doublet lens;

[0074] L8, the fourth achromatic doublet lens group;

[0075] G1, the first galvanometer;

[0076] G2, the second galvanometer. DETAILED DESCRIPTION

[0077] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0078] Example

[0079] A handheld whole-eye OCT device that achieves wide-area imaging, such as Figure 1-6 As shown, it is used to implement whole-eye OCT and OCTA on the eyeball to be tested, including an imaging system, a control system, a reference arm module B and a sample arm module C;

[0080] The imaging system comprises a frequency-sweeping laser light source 1, a fiber-optic interference module A and a photoelectric balance detector 8; the fiber-optic interference module A is arranged on the output optical path of the frequency-sweeping laser light source 1, and the fiber-optic interference module A has a plurality of output optical paths, and the photoelectric balance detector 8, the reference arm module B and the sample arm module C are respectively arranged on different output optical paths of the fiber-optic interference module A;

[0081] The sample arm module B comprises a galvanometer module E and a switching module D which are sequentially arranged on the output optical path of the optical fiber interference module A; the switching module D comprises a third achromatic doublet lens group L5, a flip mirror structure and a fourth achromatic doublet lens group L8 which are sequentially arranged on the output optical path of the galvanometer module E, wherein the third achromatic doublet lens group L5 and the fourth achromatic doublet lens group L8 form a telescope system for implementing wide-angle scanning in the posterior segment of the eye; the switching module D implements switching of different imaging parts of the eyeball to be tested through the flip mirror structure;

[0082] The eyeball to be tested is located on the output light path of the sample arm module C;

[0083] The control system is electrically connected to the frequency-sweeping laser light source 1 , the photoelectric balance detector 8 , and the galvanometer module E respectively.

[0084] More specifically, in this embodiment:

[0085] refer to Figure 1 This embodiment provides a handheld whole-eye OCT device capable of achieving wide-area imaging, including an imaging system, a control system, a reference arm module B, and a sample arm module C.

[0086] In this embodiment, the imaging system specifically includes a swept-frequency laser light source 1, a fiber interferometer module A (specifically including a first fiber coupler 2, a second fiber coupler 3, a first circulator 4, a second circulator 5, a first polarization controller 6, and a second polarization controller 7), and a photoelectric balanced detector 8.

[0087] In this embodiment, in the fiber interference module A, the laser from the frequency-sweeping laser light source 1 passes through the first fiber coupler 2, and then provides incident light to the reference arm module B through the first circulator 4 and the first polarization controller 6, and provides incident light to the sample arm module C through the second circulator 5 and the second polarization controller 7. The reference light reflected from the reference arm module B enters the second fiber coupler 3 after passing through the first polarization controller 6 and the first circulator 4; the light reflected from the sample arm module C enters the second fiber coupler 3 after passing through the second polarization controller 7 and the second circulator 5. Interference occurs in the second fiber coupler 3 and generates interference light. After the interference light is detected by the photoelectric balance detector 8 and processed by the control system, optical coherence tomography imaging of the human eye is obtained.

[0088] In this embodiment, the control system includes a high-speed acquisition card 9 and a signal acquisition card 10. The electrical signal output end of the photoelectric balance detector 8 is connected to the high-speed acquisition card 9, and the output end of the high-speed acquisition card 9 is connected to the digital signal acquisition card 10; the output end of the swept laser light source 1 is connected to the high-speed acquisition card 9; the digital signal acquisition card 10 is used to process the signal to obtain OCT / OCTA images.

[0089] In this embodiment, the reference arm module B includes a first beam expander collimator L1, a first reflector 11, a second reflector 12, a third reflector 13, a fourth reflector 14, and a fifth reflector 15. The optical path matching of the front and rear segments of the corresponding eye is performed by flipping the first reflector 11 and the fourth reflector 14 (implemented by a flip frame).

[0090] In this embodiment, the sample arm module C includes a second beam expansion collimator L2, an electric focusing lens L3, a galvanometer module E and a switching module D.

[0091] refer to Figure 2 , the galvanometer module E includes a first galvanometer G1, a first achromatic doublet lens group L4, a second achromatic doublet lens group L5, and a second galvanometer G2, wherein the first achromatic doublet lens group L4 and the second achromatic doublet lens group L5 form a 4F system, through which there will be no scanning focus difference on the pupil, and the axis-related vignetting artifacts are eliminated. In addition, the galvanometer module E is also connected to the control system by electrical connection, and the control system transmits a signal to the galvanometer module E to control the movement of the galvanometer therein to change the scanning path and angle, thereby realizing scanning of different imaging areas. Specifically, the first galvanometer G1 and the second galvanometer G2 in the galvanometer module E are respectively responsible for light beam deflection in different directions, and the control system accurately controls the rotation angle of the two galvanometers by adjusting the electrical signal to realize accurate control of the scanning light path.

[0092] The switching module D includes a third achromatic doublet lens group L6, a sixth reflecting mirror 16, a seventh reflecting mirror 17, an eighth reflecting mirror 18, a ninth reflecting mirror 19, an achromatic doublet lens L7, and a fourth achromatic doublet lens group L8.

[0093] The components of the switching module D are composed of an anterior segment structure / function imaging subsystem (anterior segment imaging mode, imaging the anterior segment of the eyeball to be tested) and a posterior segment structure / function imaging subsystem (posterior segment imaging mode, imaging the posterior segment of the eyeball to be tested), which can realize OCT / OCTA imaging of different parts of the whole eye. In addition, the switching module D switches different imaging parts through a flip mirror device, which refers to a reflector (sixth reflector 16, seventh reflector 17, eighth reflector 18, ninth reflector 19, achromatic doublet lens L7) arranged between the third achromatic doublet lens group L6 and the fourth achromatic doublet lens group L8, which can directly switch the anterior segment imaging and posterior segment imaging modes.

[0094] refer to Figure 3 The optical path of the anterior segment structure / function imaging subsystem (in the anterior segment imaging mode, when imaging the anterior segment of the eyeball to be tested) passes through the third achromatic doublet lens group L6, the seventh reflector 17, the eighth reflector 18, the ninth reflector 19, the achromatic doublet lens L7, and the fourth achromatic doublet lens group L8 in sequence; the optical path of the reference arm module B corresponding to the anterior segment structure / function imaging subsystem passes through the first beam expander collimator L1, the first reflector 11, the second reflector 12, the third reflector 13, the fourth reflector 14, and the fifth reflector 15 in sequence.

[0095] The third achromatic doublet lens group L6, the seventh reflector 17, the eighth reflector 18, the ninth reflector 19, the achromatic doublet lens L7, and the fourth achromatic doublet lens group L8 are arranged at positions that: the light from the signal light input arm sequentially passes through the third achromatic doublet lens group L6, the seventh reflector 17, the eighth reflector 18, the ninth reflector 19, the achromatic doublet lens L7, and the fourth achromatic doublet lens group L8, and converges to the anterior segment of the eyeball to be tested and focuses through the fourth achromatic doublet lens group L8. The first beam expander collimator L1, the first reflector 11, the second reflector 12, the third reflector 13, the fourth reflector 14, and the fifth reflector 15 are arranged at positions that: the light from the first beam expander collimator L1 sequentially passes through the first reflector 11, the second reflector 12, the third reflector 13, and the fourth reflector 14 to reach the fifth reflector 15 and reflect back to the original path.

[0096] Among them, for the anterior segment structure / function imaging subsystem, the light coming from the galvanometer module E is a parallel light beam, which enters the third achromatic doublet lens group L6 for focusing, is reflected after passing through the seventh emitting mirror 17 at an angle of 45° on the focusing light path, is reflected after passing through the eighth reflecting mirror 18 at an angle of 45°, and then passes through the ninth reflecting mirror 19 at an angle of 45°, and is reflected again into the achromatic doublet lens L7 to be re-diverged into parallel light, and the parallel light is converged to the anterior segment of the eyeball to be tested and focused through the fourth achromatic doublet lens group L8.

[0097] In the optical path of the anterior segment structure / function imaging subsystem, the optical path must match the reference ratio optical path, and the distance between lenses is equal to the sum of the focal lengths of the lenses; therefore, after the third achromatic doublet lens group L6 in the anterior segment structure / function imaging subsystem focuses the signal light, it enters the achromatic doublet lens L7 after being reflected by the seventh reflector 17, the eighth reflector 18 and the ninth reflector 19. Since the sum of the optical path distance and the focal length of the lens is equal, the focused light is re-diverged into parallel light, and then focused on the anterior segment of the eye by the fourth achromatic doublet lens group L8, where the fourth achromatic doublet lens group L8 acts as the posterior segment lens.

[0098] The optical path of the posterior segment structure / function imaging subsystem (which is a posterior segment imaging mode and images the posterior segment of the eyeball to be tested) passes through the third achromatic doublet lens group L6, the sixth reflector 16 and the fourth achromatic doublet lens group L8 in sequence, wherein the focal length f1 of the third achromatic doublet lens group L6 is greater than the focal length f3 of the fourth achromatic doublet lens group (f1>f3). The optical path of the posterior segment structure / function imaging subsystem corresponding to the reference arm module B passes through the first beam expander collimator L1 to the fifth reflector 15.

[0099] refer to Figure 4 The third achromatic doublet lens group L6 and the fourth achromatic doublet lens group L8 form a telescope system, through which the scanning angle of the galvanometer module E is enlarged to achieve wide-angle imaging of the posterior segment of the eye.

[0100] refer to Figure 5 The third achromatic doublet lens group L6, the sixth reflector 16 and the fourth achromatic doublet lens group L8 are arranged at positions that: the light from the galvanometer module E passes through the third achromatic doublet lens group L6, the sixth reflector 16 and the fourth achromatic doublet lens group L8 in sequence. The first beam expander collimator L1 and the fifth reflector 15 are arranged at positions that: the light from the first beam expander collimator L1 reaches the fifth reflector 15 and is reflected back to the original path.

[0101] Among them, for the posterior segment structure / function imaging subsystem, the light coming from the galvanometer module E is a parallel light beam, which enters the third achromatic doublet lens group L6 for focusing. After focusing, the light is reflected by the sixth reflector 16 at an angle of 45°, and then enters the fourth achromatic doublet lens group L8. After being focused and diverged by the third achromatic doublet lens group L6 and the fourth achromatic doublet lens group L8, it becomes parallel light again, wherein the distance between the third achromatic doublet lens group L6 and the fourth achromatic doublet lens group L8 is equal to the sum of the focal lengths of the two lenses, and the parallel light beam enters the lens of the eye to be tested, and the lens focuses the incident parallel light onto the retina for imaging.

[0102] In the optical path of the posterior segment structure / function sub-imaging system, the third achromatic doublet lens group L6 focuses the signal light and transmits it through the sixth reflector 16, which is then diverged by the fourth achromatic doublet lens group L8 into parallel light that enters the eye and is focused to the posterior segment for imaging through the focusing action of the lens.

[0103] refer to Figure 1 The sample arm module C includes a second beam expander collimator L2, an electric focusing lens L3, a galvanometer module E and a switching module D. The second beam expander collimator L2 is used to receive the laser light source injected after being processed by the fiber interference module A. The electric focusing lens L3 is used to transmit the light beam to the first galvanometer G1. The first galvanometer G1 is used to reflect and deflect the light beam to form a parallel light beam. The parallel light beam enters the 4F system composed of a first achromatic doublet lens group L4 and a second achromatic doublet lens group L5. The light of the 4F system is transmitted to the second galvanometer G2 to reflect and deflect the light beam to the anterior segment structure / function imaging subsystem or the posterior segment structure / function imaging subsystem of the switching module D.

[0104] In the optical path of the posterior segment structure / function imaging subsystem, the optical path must match the optical path of the reference arm (the optical path difference is kept within the range of the light source coherence length), and the distance between lenses and the focal length must match (the distance between lenses is the sum of the focal lengths of the lenses).

[0105] In this embodiment, considering the need for imaging the anterior segment of the eye and the retina and choroid at a large angle, the optical path is designed to focus the sample light in front of the lens and the rear end of the retina through optical conversion. In order to achieve the requirement of wide-angle scanning in the posterior segment of the eye, a telescope system is used at the sample arm module C to increase the scanning angle, and a 4F system is used in the galvanometer module E to eliminate vignetting artifacts. The device is simple and easy to operate.

[0106] In this embodiment, the first achromatic doublet lens group L4, the second achromatic doublet lens group L5, the third achromatic doublet lens group L6, and the fourth achromatic doublet lens group L8 are all lens groups composed of two achromatic doublet lenses, and the achromatic doublet lens L7 is an optical structure that combines two single lenses together.

[0107] In summary, when the solution of this embodiment is used:

[0108] Anterior segment imaging mode: after receiving the imaging scanning instruction, the frequency-sweeping laser light source 1 emits a broadband pulse laser and enters the first fiber coupler 2. Subsequently, a portion of the light enters the first circulator 4, passes through the first polarization controller 6, and then passes through the first beam expander collimator L1, the first reflector 11, the second reflector 12, the third reflector 13, the fourth reflector 14, and the fifth reflector 15 in sequence, and returns to the first circulator 4 along the original path under the reflection of the fifth reflector 15, and then enters the second fiber coupler 3. Another part of the light enters the second circulator 5, passes through the second polarization controller 7, and then passes through the second beam expander collimator L2, the electric focus lens L3, the first galvanometer G1, the first achromatic doublet lens group L4, the second achromatic doublet lens group L5, and the second galvanometer G2 in sequence. The parallel light beam enters the third achromatic doublet lens group L6 for focusing, and is reflected after passing through the seventh emitting mirror 17 at an angle of 45° on the focusing light path, and then is reflected after passing through the eighth reflecting mirror 18 at an angle of 45°, and then passes through the ninth reflecting mirror 19 at an angle of 45°, and is reflected again into the achromatic doublet lens L7 and diverges again to become parallel light. The parallel light is converged to the anterior segment of the eyeball to be tested through the fourth achromatic doublet lens group L8 and is focused. The collected optical signal returns to the second circulator 5 along the original path, and then enters the second optical fiber coupler 3. Interference occurs in the second optical fiber coupler 3 and interference light is generated. After the interference light is detected by the photoelectric balance detector 8, it is processed by the control system to obtain the optical coherence tomography imaging of the human eye.

[0109] Posterior segment imaging mode: after receiving the imaging scanning instruction, the frequency-sweeping laser light source 1 emits a broadband pulse laser and enters the first fiber coupler 2. Subsequently, a portion of the light enters the first circulator 4, passes through the first polarization controller 6, and then passes through the first beam expander collimator L1 to the fifth reflector 15, and returns to the first circulator 4 along the original path under the reflection of the fifth reflector 15, and then enters the second fiber coupler 3. Another part of the light enters the second circulator 5, passes through the second polarization controller 7, and then passes through the second beam expander collimator L2, the electric focusing lens L3, the first galvanometer G1, the first achromatic double glued lens group L4, the second achromatic double glued lens group L5, and the second galvanometer G2 in sequence. The parallel light beam enters the third achromatic double glued lens group L6 for focusing. After focusing, the light is reflected by the sixth reflector 16 at an angle of 45°, and directly enters the fourth achromatic double glued lens group L8. After being focused and diverged by the third achromatic double glued lens group L6 and the fourth achromatic double glued lens group L8, it becomes parallel light again. The distance between the third achromatic double glued lens group L6 and the fourth achromatic double glued lens group L8 is equal to the sum of the focal lengths of the two lenses. The parallel light beam enters the lens of the eyeball to be tested, and the lens focuses the incident parallel light on the retina for imaging. The collected optical signal returns to the second circulator 5 by the original path, and then enters the second optical fiber coupler 3. Interference occurs in the second optical fiber coupler 3 and generates interference light. After the interference light is detected by the photoelectric balance detector 8 and processed by the control system, optical coherence tomography of the human eye is obtained.

[0110] refer to Figure 6 , Figure 6 This is a spot diagram of the posterior segment structure / function imaging system. The spot diagram shows that the RMS radius of each field of view is smaller than the diffraction-limited Airy disk radius of 23.43 μm, indicating that the image quality of this device is high.

[0111] In this embodiment, the light source of OCT / OCTA provides incident light to the sample arm module C and the reference arm module component B respectively through the optical fiber coupler, wherein the light of the sample arm module part C is incident on the anterior segment of the eye or the posterior segment of the eye and reflected, and the returned light passes through the sample arm module C and interferes with the light returned from the reference arm module B in the optical fiber coupler to generate interference light, and the interference light is input into the photoelectric balance detector for processing, and then processed by the computer system to obtain the OCT / OCTA tomographic imaging of the human eye.

[0112] The present invention aims to solve the problem of small imaging field of existing handheld OCT devices, and realizes wide-angle imaging in the posterior segment of the eye by using a telescope system in the posterior segment structure / function imaging subsystem. At the same time, the volume and weight of the handheld end of the system (sample arm module C) are small, and the construction of a handheld OCT device can be finally realized. The device uses a 4F system to solve the problem of vignetting artifacts generated during the imaging process, and realizes high-quality imaging. The device can realize large-angle posterior segment structure / blood flow imaging, and a handheld whole-eye imaging device, which is of great significance for real-time imaging research of eye diseases.

[0113] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A handheld whole-eye OCT device for wide-area imaging, used for performing whole-eye OCT and OCTA on an eyeball to be tested, characterized in that: It includes an imaging system, a control system, a reference arm module (B) and a sample arm module (C); The imaging system comprises a frequency-sweeping laser light source (1), a fiber-optic interference module (A) and a photoelectric balance detector (8); the fiber-optic interference module (A) is arranged on the output light path of the frequency-sweeping laser light source (1), and the fiber-optic interference module (A) has a plurality of output light paths; the photoelectric balance detector (8), the reference arm module (B) and the sample arm module (C) are respectively arranged on different output light paths of the fiber-optic interference module (A); The sample arm module (C) comprises a galvanometer module (E) and a switching module (D) which are sequentially arranged on the output light path of the optical fiber interference module (A); the switching module (D) comprises a third achromatic doublet lens group (L6), a flip mirror structure and a fourth achromatic doublet lens group (L8) which are sequentially arranged on the output light path of the galvanometer module (E), wherein the third achromatic doublet lens group (L6) and the fourth achromatic doublet lens group (L8) form a telescope system for performing wide-angle scanning in the posterior segment of the eye; the switching module (D) switches between different imaging parts of the eyeball to be tested through the flip mirror structure; The eyeball to be tested is located on the output light path of the sample arm module (C); The control system is electrically connected to the frequency-sweeping laser light source (1), the photoelectric balance detector (8), and the galvanometer module (E) respectively.

2. A handheld whole-eye OCT device for wide-area imaging according to claim 1, characterized in that: The flip mirror structure comprises a sixth reflector (16), a seventh reflector (17), an eighth reflector (18), a ninth reflector (19) and an achromatic doublet lens (L7) which are sequentially arranged on the output light path of the third achromatic doublet lens group (L6), and the sixth reflector (16) is also on the output light path of the achromatic doublet lens (L7); The sixth reflecting mirror (16) reflects the output light path of the third achromatic doublet lens group (L6) to the fourth achromatic doublet lens group (L8) or the seventh reflecting mirror (17), thereby switching different imaging parts of the eyeball to be measured.

3. A handheld whole-eye OCT device for wide-area imaging according to claim 2, characterized in that: When the sixth reflector (16) reflects the output light path of the third achromatic doublet lens group (L6) to the fourth achromatic doublet lens group (L8), it is a posterior segment imaging mode, and the distance between the lenses matches the focal length of the lenses; When the sixth reflecting mirror (16) reflects the output light path of the third achromatic doublet lens group (L6) to the seventh reflecting mirror (17), it is an anterior segment imaging mode, and the distance between the lenses is equal to the sum of the focal lengths of the lenses.

4. A handheld whole-eye OCT device for wide-area imaging according to claim 1, characterized in that: The focal length f1 of the third achromatic doublet lens group (L6) is greater than the focal length f3 of the fourth achromatic doublet lens group (L8).

5. The handheld whole-eye OCT device for realizing wide-area imaging according to claim 1, characterized in that: The galvanometer module (E) comprises a first galvanometer (G1), a first achromatic doublet lens group (L4), a second achromatic doublet lens group (L5) and a second galvanometer (G2) which are sequentially arranged on the output light path of the optical fiber interference module (A); The control system is electrically connected to the first galvanometer (G1) and the second galvanometer (G2) respectively.

6. A handheld whole-eye OCT device for wide-area imaging according to claim 5, characterized in that: The first achromatic doublet lens group (L4) and the second achromatic doublet lens group (L5) form a 4F system.

7. The handheld whole-eye OCT device for wide-area imaging according to claim 1, characterized in that: The sample arm module (C) further comprises a second beam expansion collimator (L2) and an electric focusing lens (L3); The second beam expansion collimator (L2) and the electric focusing lens (L3) are sequentially arranged on the optical path between the optical fiber interference module (A) and the galvanometer module (E).

8. The handheld whole-eye OCT device for wide-area imaging according to claim 1, characterized in that: The reference arm module (B) comprises a first beam expander collimator (L1), a first reflector (11), a second reflector (12), a third reflector (13), a fourth reflector (14) and a fifth reflector (15) which are sequentially arranged on the output light path of the optical fiber interference module (A); The reference arm module (B) satisfies: the reflected light path coincides with the incident light path.

9. The handheld whole-eye OCT device for wide-area imaging according to claim 1, characterized in that: The optical fiber interference module (A) comprises a first optical fiber coupler (2), a second optical fiber coupler (3), a first circulator (4), a second circulator (5), a first polarization controller (6) and a second polarization controller (7); The first circulator (4) is connected to the first optical fiber coupler (2), the second optical fiber coupler (3) and the first polarization controller (6) respectively through optical fibers; the reference arm module (B) is located on the output optical path of the first polarization controller (6); The second circulator (5) is connected to the first optical fiber coupler (2), the second optical fiber coupler (3) and the second polarization controller (7) respectively through optical fibers; the sample arm module (C) is located on the output optical path of the second polarization controller (7); The second optical fiber coupler (3) is connected to the photoelectric balance detector (8) via an optical fiber.

10. The handheld whole-eye OCT device for realizing wide-area imaging according to claim 1, characterized in that: The control system comprises a high-speed acquisition card (9) and a signal acquisition card (10); The high-speed acquisition card (9) is electrically connected to the frequency-sweeping laser light source (1), the photoelectric balance detector (8) and the signal acquisition card (10) respectively; The signal acquisition card (10) is electrically connected to the galvanometer module (E).

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