CN111557637B

CN111557637B - Ophthalmic measurement system

Info

Publication number: CN111557637B
Application number: CN201910116857.2A
Authority: CN
Inventors: 蔡守东; 郭曙光; 吴蕾; 代祥松; 李鹏; 王辉
Original assignee: Shenzhen Moting Medical Technology Co ltd
Current assignee: Shenzhen Moting Medical Technology Co ltd
Priority date: 2019-02-13
Filing date: 2019-02-13
Publication date: 2024-09-03
Anticipated expiration: 2039-02-13
Also published as: CN111557637A

Abstract

An ophthalmic measuring system is used for detecting an inspected eye and comprises a main body module, a reference plane, a switching scanning element, an eye front section optical path component, an eye back section optical path component and a light splitting element, wherein the eye front section optical path component, the eye back section optical path component and the light splitting element are all arranged on the reference plane, the switching scanning element can rotate around a certain axis so as to realize the switching of an optical path between the eye front section optical path component and the eye back section optical path component and can horizontally scan the eye front section and the eye back section of the inspected eye. The invention can realize the switching of the scanning of the front section and the rear section of the eye to be detected based on the spectral domain OCT technology so as to determine the axial length of the eye to be detected, can overcome the defects of complex structure and high cost in the prior art, and can realize horizontal scanning.

Description

Ophthalmic measurement system

Technical Field

The invention belongs to the field of ophthalmic examination equipment, and particularly relates to an ophthalmic measurement system.

Background

The effective prevention and treatment of cataract surgery, corneal refractive surgery, and juvenile myopia require accurate measurement of various parameters of the eye, such as anterior and posterior surface curvature of the cornea, corneal thickness, anterior chamber depth, lens thickness, anterior and posterior surface curvature of the lens, axial length of the eye, white-to-white distance, pupil diameter, etc. In the prior art, the most widely used technique for obtaining the plurality of parameters is the ultrasonic technique, but the measurement accuracy thereof is low.

In view of the drawbacks of the ultrasound technique, ophthalmic measurement systems based on OCT (Optical Coherence Tomography ) techniques have been developed for obtaining said plurality of parameters. OCT is an emerging optical imaging technology, has the advantages of high resolution, fast imaging speed, no radiation damage, compact structure, etc., and is an important potential tool for basic medical research and clinical diagnosis application. OCT techniques can be classified into TDOCT (Time Domain OCT) and FDOCT (Frequency Domain OCT ), which in turn can be further classified into ssooct (Swept Source OCT ) and SDOCT (Spectral Domain OCT, spectral Domain OCT). The ophthalmology measurement system is easy to realize based on the time domain OCT technology or the sweep source OCT technology, and the implementation difficulty of the technology based on the spectral domain OCT is high.

Chinese patent application number 200710020707.9 discloses a method for measuring the length of the eye axis, which is the length from the corneal vertex to the fovea of the macula, using time domain OCT. The method adopts a stepping motor to move the probe back and forth so as to realize the adjustment of the optical path, thereby imaging the cornea and the fundus, and has the following defects: 1) The imaging time required by the forward and backward movement of the stepping motor is long, real-time imaging cannot be performed, and a measured object can shake, blink and the like during the imaging period, so that the measured parameters such as the eye axis length and the like have larger errors; 2) The method can not carry out transverse scanning on eyes and can not judge the positions of the corneal vertex and the macula fovea, so that the measured eye axial length has larger difference with the actual eye axial length; 3) The cornea and retina have cornea, aqueous humor, lens, etc. organs, refract the light entering the eye, the method can not realize the focusing of the measurement light at the same time of cornea and retina, the imaging quality is poor.

In particular, ophthalmic measurement systems based on time domain OCT have the disadvantages of slow imaging speed, low measurement accuracy, poor image quality, etc., but the disadvantages of ultrasound technology are not overcome in practice. While the ophthalmic measurement system based on the sweep source OCT technology overcomes a plurality of defects of the ultrasonic technology, the ophthalmic measurement system is high in price and difficult to popularize.

Chinese patent publication No. CN103892791a discloses a system and method that can implement switching of anterior and posterior eye segment scans of an eye to be inspected to determine the eye axial length of the eye to be inspected based on spectral domain OCT techniques. However, the device adopts a plurality of switching mechanisms, and the switching mechanisms can be matched with each other to realize the switching of the scanning of the front section and the back section of the eye to be inspected, so that the device has a complex structure and is not easy to maintain; high cost and difficult popularization.

Disclosure of Invention

Based on the OCT technology, the invention provides an ophthalmic measurement system, belongs to another technical scheme capable of realizing the switching of the scanning of the front section and the back section of the eye to be inspected so as to determine the axial length of the eye to be inspected based on the spectral domain OCT technology, and can overcome the defects of complex structure and high cost in the prior art.

The technical scheme provided by the embodiment of the invention is as follows:

An ophthalmic measurement system for detecting an eye to be inspected comprises a main body module, a reference plane, a switching scanning element, an anterior ocular segment optical path component, a posterior ocular segment optical path component, a beam splitting element and a system main optical axis, wherein the main body module is used for providing measurement light and reference light, receiving first anterior ocular segment signal light and second posterior ocular segment signal light, respectively interfering the first anterior ocular segment signal light and the second posterior ocular segment signal light with the reference light and collecting corresponding interference light; the system main optical axis comprises an emergent main optical axis, the emergent main optical axis is positioned on the reference plane, the switching scanning element can rotate around a certain axis, and the switching scanning element is provided with a first working position and a second working position and can be switched between the first working position and the second working position by rotating around the fixed axis; the anterior ocular segment optical path component comprises a first reflecting mirror, the posterior ocular segment optical path component comprises a retroreflection element and an optical element, and the intersection point of the system main optical axis and the first reflecting mirror and the intersection point of the system main optical axis and the optical element are both positioned on the reference plane; when the switching scanning element is in the first working position, the measuring light provided by the main body module is reflected to the first reflector by the switching scanning element, reflected to the light splitting element by the first reflector, conducted to the inspected eye by the light splitting element, scattered by the front eye of the inspected eye to form front eye section signal light, scattered to the light splitting element by the front eye section of the inspected eye, the light splitting element divides the front eye section signal light into the first front eye section signal light and the second front eye section signal light, conducts the first front eye section signal light to the first reflector, reflects to the switching scanning element by the first reflector and enters the main body module by the switching scanning element,

When the switching scanning element is in the second working position, the measuring light provided by the main body module is reflected to the retroflection element by the switching scanning element, reflected to the optical element by the retroflection element, reflected to the light splitting element by the optical element, transmitted to the inspected eye by the light splitting element, scattered by the posterior segment of the inspected eye to form posterior segment signal light, scattered to the light splitting element by the posterior segment of the inspected eye, and the light splitting element divides the posterior segment signal light into first posterior segment signal light and second posterior segment signal light, transmits the second posterior segment signal light to the optical element, and the second posterior segment signal light is reflected to the retroflection element by the optical element, reflected to the retroflection element by the retroflection element, reflected to the switching scanning element by the switching scanning element and reflected to the main body module.

In a preferred embodiment of the present invention, the switching scan element is rotatable about the fixed axis in the first working position to scan the anterior ocular segment of the eye to be inspected, the switching scan element is rotatable about the fixed axis in the second working position, and the switching scan element is rotatable about the fixed axis in the second working position to scan the posterior ocular segment of the eye to be inspected.

In a preferred embodiment of the invention, the fixed axis is parallel to the exit primary optical axis when the system is in a detection condition.

In a preferred embodiment of the present invention, the retroreflective element includes a first reflecting surface and a second reflecting surface, an intersection point of the main optical axis of the system and the second reflecting surface is located on the reference plane, and when the switching scanning element is in the second working position, the measuring light is reflected by the switching scanning element to the first reflecting surface, and then reflected by the first reflecting surface and the second reflecting surface to the optical element in sequence.

In a preferred embodiment of the present invention, the anterior ocular segment optical path component includes a second reflecting mirror, where the second reflecting surface, the optical element, the first reflecting mirror, the switching scanning element, and the second reflecting mirror are sequentially arranged along a direction perpendicular to the exit main optical axis, and when the switching scanning element is in the first working position, the measuring light provided by the main body module is reflected by the switching scanning element to the first reflecting mirror, reflected by the first reflecting mirror to the second reflecting mirror, and reflected by the second reflecting mirror to the light splitting element.

In a preferred embodiment of the present invention, the anterior ocular segment optical path component comprises a third mirror, a line connecting an intersection point of the system main optical axis and the first mirror and an intersection point of the system main optical axis and the second mirror is perpendicular to the outgoing main optical axis, a line connecting an intersection point of the system main optical axis and the second mirror, and an intersection point of the system main optical axis and the third mirror is parallel to the outgoing main optical axis, and a line connecting an intersection point of the system main optical axis and the third mirror and an intersection point of the system main optical axis and the light splitting element is perpendicular to the outgoing main optical axis; when the switching scanning element is in the first working position, the measuring light provided by the main body module is reflected to the first reflecting mirror by the switching scanning element, reflected to the second reflecting mirror by the first reflecting mirror, reflected to the third reflecting mirror by the second reflecting mirror, and reflected to the light splitting element by the third reflecting mirror.

In a preferred embodiment of the invention, the retroreflective elements are movable in a direction perpendicular to the exit principal optical axis.

In a preferred embodiment of the present invention, the switching scanning element is located outside the reference plane, and the fixed axis is parallel to the reference plane and perpendicular to the exit main optical axis.

In a preferred embodiment of the present invention, the retroreflective element includes a first reflecting surface and a second reflecting surface, a line connecting an intersection point of the system main optical axis and the switching scanning element and an intersection point of the system main optical axis and the first reflecting surface is perpendicular to the reference plane, a line connecting an intersection point of the system main optical axis and the second reflecting surface and an intersection point of the system main optical axis and the optical element is also perpendicular to the reference plane, and when the switching scanning element is in the second working position, the measuring light is reflected by the switching scanning element to the first reflecting surface and then reflected by the first reflecting surface and the second reflecting surface to the optical element.

In a preferred embodiment of the present invention, the anterior ocular segment optical path component comprises a second mirror, and a line connecting the intersection point of the system main optical axis and the first mirror and the intersection point of the system main optical axis and the second mirror is parallel to the exit main optical axis, and a line connecting the intersection point of the system main optical axis and the second mirror and the intersection point of the system main optical axis and the beam splitting element is perpendicular to the exit main optical axis; when the switching scanning element is in the first working position, the measuring light provided by the main body module is reflected to the first reflecting mirror by the switching scanning element, reflected to the second reflecting mirror by the first reflecting mirror, and reflected to the light splitting element by the second reflecting mirror.

In a preferred embodiment of the invention, the retroreflective elements are movable in a direction perpendicular to the reference plane.

In a preferred embodiment of the present invention, the reference plane is perpendicular to a line connecting pupil centers of left and right eyes of the eye to be inspected when the system is in a detection working condition.

In a preferred embodiment of the present invention, the system includes a scan plane, the scan plane is perpendicular to the reference plane, the exit main optical axis is located in the scan plane, when the system is in a detection working condition, a connecting line between centers of pupils of left and right eyes of the detected eye is located in the scan plane, and paths of the measurement light transmitted to the detected eye through the light splitting element are all located in the scan plane.

According to the ophthalmic measuring system provided by the embodiment of the invention, the rotation angle of the switching scanning element is controlled to rapidly switch the anterior ocular segment imaging or the posterior ocular segment imaging of the eye to be detected, and the relevant parameters of the eye to be detected are obtained by calculating the optical path difference between the anterior ocular segment imaging and the posterior ocular segment imaging; and the switching scanning element also has a scanning function, so that the scanning of the anterior segment and the posterior segment of the eye to be inspected can be realized. Compared with the prior art, the invention provides another technical scheme capable of realizing the switching of the scanning of the front section and the back section of the eye to be inspected so as to determine the axial length of the eye to be inspected based on the spectral domain OCT technology, and meanwhile, the defects of complex structure and high cost of the prior art can be overcome.

Furthermore, the ophthalmic measuring system provided by the embodiment of the invention has the advantages that the anterior ocular segment optical path component and the posterior ocular segment optical path component are both positioned on the reference plane, the vertical arrangement of the optical path structure can be realized, the appearance of the ophthalmic measuring system is attractive, the ophthalmic measuring system accords with the ergonomics, and the pressing sense of a tested patient is avoided. On the basis, the switching scanning element can rotate around a certain axis to realize anterior ocular segment scanning and posterior ocular segment scanning and switch between anterior ocular segment scanning and posterior ocular segment scanning, so that the eye to be inspected can be scanned in the horizontal direction.

Drawings

Fig. 1 is a schematic block diagram of an ophthalmic measurement system according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of the ophthalmic measurement system of fig. 1.

Fig. 3 is a schematic diagram illustrating an operation principle of the switching scan element in fig. 2.

Fig. 4 is a schematic structural view of a retroreflective element according to an alternative embodiment of the present invention.

Fig. 5 (a) to 5 (b) are timing diagrams of the switching scan element and the detector in fig. 2.

Fig. 6 is a schematic diagram showing the distribution of the illumination lamps in the illumination light source in fig. 2.

Fig. 7 is a schematic block diagram of an ophthalmic measurement system according to a second embodiment of the present invention.

Fig. 8 is a schematic diagram of the ophthalmic measurement system of fig. 7.

Fig. 9 is a schematic diagram illustrating the operation of the switching scan element in fig. 8.

The reference symbols in the figures are as follows:

In embodiment one:

The main optical axis L of the system exits the main optical axis L ₁ to be inspected eye E

Main body module 100

Reference arm assembly 130 for detector 105 of coupler 103 of light source 101

Reference arm lens 131 references arm mirror 133 polarization controller 107

Focusing lens 109 controller 111

Reference plane 10

First end 11, second end 13, third end 15, fourth end 17

Switching scanning element 30

The first working position 30a and the second working position 30b are fixed on the shaft 33

Anterior ocular segment optical path assembly 50

First mirror 51 first relay lens 53 second mirror 55

Third mirror 57 second relay lens 59

Posterior segment optic path assembly 70

Retroreflective element 71 optical element 73 refractive adjustment element 75

Light splitting element 80

Eye objective 90

Fixation optical module 300

Fixation lens 303 of fixation light source 301

Anterior ocular segment imaging module 500

Lighting source 501 lighting lamp 501a spectroscope 502 vision expanding lens 503

Third mirror 505 imaging lens 507 imaging device 509

In embodiment two:

Main body module 2100

Light source 2101 coupler 2103 detector 2105 reference arm assembly 2130

Reference arm lens 2131 reference arm mirror 2133 polarization controller 2107

Focusing lens 2109 controller 2111

Reference plane 210

First end 211, second end 213, third end 215, fourth end 217

Switching scan element 230

The first working position 230a and the second working position 230b are fixed on the shaft 233

Anterior ocular segment optical path assembly 250

First mirror 251 first relay lens 253 second mirror 255

Second relay lens 259

Posterior segment optic path assembly 270

Retroreflective element 271 optical element 273 refraction modulating element 275

Light splitting element 280

Eye objective 290

Fixation optical module 2300

Fixation lens 2303 of fixation light source 2301

Anterior ocular segment imaging module 2500

Illumination light source 2501 illumination lamp 2501a spectroscope 2502 magnifying lens 2503

Third mirror 2505 imaging lens 2507 camera 2509

Detailed Description

The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Example 1

The present embodiment provides an ophthalmic measurement system (hereinafter referred to as "system") for detecting an eye E to be inspected, thereby determining an eye axis length of the eye E to be inspected. Preferably, the system may also determine a plurality of parameters of the eye E, such as the cornea curvature, anterior chamber depth, white-to-white distance, pupil diameter, etc. of the eye E.

Referring to fig. 1 and 2, the system includes a main body module 100, a reference plane 10, a scanning plane (not shown), a switching scanning element 30, an anterior ocular segment optical path assembly 50, a posterior ocular segment optical path assembly 70, a spectroscopic element 80, and a system main optical axis L. Preferably, the system further comprises an objective lens 90, a fixation optical module 300 and an anterior ocular segment imaging module 500.

In fig. 1,2, the dash-dot line illustrates a system main optical axis L, which includes an exit main optical axis L ₁, and the exit main optical axis L ₁ is located in the reference plane and the scan plane. When the system is in a detection working condition, the main body module 100 generates reference light and provides measurement light to the switching scanning element 30, the measurement light is transmitted to the anterior ocular segment optical path assembly 50 or the posterior ocular segment optical path assembly 70 according to the rotation angle of the switching scanning element 30, and is focused to a corresponding part of the detected eye E through the objective lens 90 after being reflected or transmitted by the light splitting element 80, and then is scattered by the detected eye E to form signal light, the signal light propagates back to the main body module 100 along a direction opposite to the measurement light and interferes with the reference light to generate interference light, and the main body module 100 also collects the interference light. The paths of the measuring light transmitted to the eye to be inspected by the light splitting element are all positioned on the scanning plane.

The reference plane 10 is perpendicular to the line connecting the pupil centers of the left eye and the right eye of the eye to be inspected E when the system is in the detection working condition, the reference plane 10 comprises a first end 11, a second end 13 which is opposite to the first end 11 and is parallel to the first end 11, a third end 15 which is perpendicular to the first end 11, and a fourth end 17 which is opposite to the third end 15 and is parallel to the third end 15, and the first end 11, the second end 13, the third end 15 and the fourth end 17 are connected end to form a closed rectangle. The first end 11 and the second end 13 are perpendicular to the exit main optical axis L ₁, and the third end 15 and the fourth end 17 are parallel to the exit main optical axis L ₁.

It will be appreciated that the reference plane 10 is a virtual plane that describes the positional relationship of the various components of the system.

The scanning plane is perpendicular to the reference plane 10, and when the system is in a detection working condition, a connecting line of the pupil centers of the left eye and the right eye of the detected eye E is positioned on the scanning plane. The scan plane is perpendicular to the reference plane. The reference plane is perpendicular to the connecting line of the pupil centers of the left eye and the right eye of the detected eye E. It will be appreciated that the scan plane is also a virtual plane describing the positional relationship of the various components of the system.

As shown in fig. 2, in the present embodiment, the main body module 100 includes a light source 101, a coupler 103, a reference arm assembly 130, a detector 105, a polarization controller 107, a focus lens 109, and a controller 111. The reference arm assembly 130 further includes a reference arm lens 131 and a reference arm mirror 133. The light source 101 may be an OCT light source, which emits weak coherent light with a wavelength of near infrared, and transmits the weak coherent light to the coupler 103, and the coupler 103 divides the received light into two beams, wherein one beam is focused by the reference arm lens 131 and reflected by the reference arm mirror 133, and then returns to the coupler 103 to be used as reference light. The other beam is sequentially focused by the polarization controller 107 and the focusing lens 109 and then transferred to the switching scanning element 30 as measurement light.

Referring to fig. 3, the dashed line in fig. 3 illustrates the system principal optical axis L. In this embodiment, the switching scan element 30 is disposed near the second end 13, and the switching scan element 30 is specifically a galvanometer. The switching scan element 30 is rotatable about a fixed axis 33, and in this embodiment, the fixed axis 33 is parallel to the reference plane 10 and parallel to the exit main optical axis L ₁, i.e. the fixed axis 33 is parallel to the second end 15, and those skilled in the art will appreciate that in other embodiments of the present invention, the fixed axis may be disposed perpendicular to the reference plane. The switching scanning element 30 has a first operating position 30a and a second operating position 30b and can be switched between the first operating position 30a and the second operating position 30b by rotation about a fixed axis 33. The direction of propagation of the measurement light may be selected by controlling the switching scan element 30 to be at different angles of rotation so that the measurement light is delivered to either the anterior ocular segment optical path assembly 50 or the posterior ocular segment optical path assembly 70. Specifically, the switching scanning element 30 may be controlled to switch between the first working position 30a and the second working position 30b, when the switching scanning element 30 is located at the first working position 30a, as shown in fig. 3, an included angle between a propagation path of incident light and a propagation path of reflected light at the switching scanning element 30 is β, and measurement light is transmitted to the anterior ocular segment optical path assembly 50; when the switching scan element 30 is in the second operating position 30b, as shown in fig. 3, the angle between the propagation path of the incident light and the propagation path of the reflected light at the switching scan element 30 is α, and the measuring light is transmitted to the posterior segment optical path assembly 70.

Specifically, in this embodiment, the system further includes an electronic control component (such as a motor), where the electronic control component has an electrically controlled rotating bracket (such as a rotating shaft), the electronic control component is electrically connected to the controller 111, the switching scanning element 30 is fixed on the electrically controlled rotating bracket, and the controller 111 controls the rotation of the electronic control component to drive the rotation of the electrically controlled rotating bracket so as to control the rotation angle of the switching scanning element 30, so that when the switching scanning element 30 rotates to the first working position 30a, it reflects the measurement light to the anterior ocular segment optical path component 50, and when the switching scanning element 30 rotates to the second working position, it reflects the measurement light to the posterior ocular segment optical path component 70.

It will be appreciated that in other embodiments of the present invention, the system may also control the angle of rotation of the switching scan element 30 by manual adjustment, in particular, the system includes a rotating bracket for fixing the switching scan element 30, the rotating bracket providing a knob by which the angle of rotation of the switching scan element 30 is adjusted manually to inject the measurement light into the corresponding position of the eye E to be inspected.

It is understood that in other embodiments of the present invention, the switching scan element 30 may be further controlled by other mechanical devices or electrical methods to perform angular rotation, and the design scheme meeting such design structure is within the scope of the present invention and will not be described herein.

Referring to fig. 2 again, in this embodiment, the measurement light reaches the light splitting element 80 after passing through the anterior ocular segment optical path assembly 50 or the posterior ocular segment optical path assembly 70, and the light splitting element 80 is specifically a half mirror, which can transmit the measurement light transmitted by the anterior ocular segment optical path assembly 50 and reflect the measurement light transmitted by the posterior ocular segment optical path assembly 70. It will be appreciated that light impinging on the half mirror is partially reflected by the half mirror and partially transmitted by the half mirror. For example, 30% of the light is reflected and 70% of the light is transmitted; for example, 50% of the light is reflected and 50% of the light is transmitted; for another example, 70% of the light is reflected and 30% of the light is transmitted.

It will be appreciated that the system can be modified by a person skilled in the art without any inventive effort, and in the modified technical solution, the half mirror serving as a beam splitting element can reflect the measurement light transmitted by the anterior segment optical path component and transmit the measurement light transmitted by the posterior segment optical path component.

Specifically, in the present embodiment, when the switching scanning element 30 is at the first working position 30a, the measurement light is transmitted through the spectroscopic element 80 and focused to the anterior ocular segment of the eye E, such as the cornea of the eye E, via the objective lens 90. When the switching scanning element 30 is in the second working position 30b, the measuring light is reflected by the spectroscopic element 80 and focused to the posterior segment of the eye E, such as the retina of the eye E, via the objective lens 90.

In this embodiment, the anterior ocular segment optical path assembly 50 comprises at least two total reflection mirrors, namely a first mirror 51 and a second mirror 55. When the switching scanning element 30 is in the first working position 30a, the light transmitted by the switching scanning element 30 is reflected to the light splitting element 80 through the first reflecting mirror 51 and the second reflecting mirror 55 in sequence.

Preferably, the anterior ocular segment optical path assembly 50 comprises three total reflection mirrors, namely a first mirror 51, a second mirror 55, and a third mirror 57. The first mirror 51 is closer to the third end 15 than the switching scan element 30, the second mirror 55 is closer to the fourth end 17 than the first mirror 51, and the third mirror 57 is closer to the first end 11 than the second mirror 55. The intersection point of the system main optical axis L and the first mirror 51, the intersection point of the system main optical axis L and the second mirror 55, and the intersection point of the system main optical axis L and the third mirror 57 are all located in the reference plane 10. The line connecting the intersection point of the system main optical axis L and the first mirror 51 and the intersection point of the system main optical axis L and the second mirror 55 is parallel to the first end 11, the line connecting the intersection point of the system main optical axis L and the second mirror 55 and the intersection point of the system main optical axis L and the third mirror 57 is parallel to the third end 15, and the line connecting the intersection point of the system main optical axis L and the third mirror 57 and the intersection point of the system main optical axis L and the spectroscopic element 80 is parallel to the first end 11. When the switching scanning element 30 is in the first working position 30a, the light transmitted by the switching scanning element 30 is reflected to the light splitting element 80 through the first reflecting mirror 51, the second reflecting mirror 55 and the third reflecting mirror 57 in order.

In this embodiment, the anterior ocular segment optical path assembly 50 further includes at least one relay lens, wherein at least one relay lens is disposed between the first mirror 51 and the second mirror 55, and when the switching scanning element 30 is rotated to the first working position 30a, the first mirror 51 reflects the measurement light to the second mirror 55 through the relay lens; or at least one relay lens is provided between the second reflecting mirror 55 and the spectroscopic element 80, and the second reflecting mirror 55 reflects the measurement light to the spectroscopic element 80 through the relay lens.

Preferably, in the present embodiment, the anterior ocular segment optical path assembly 50 includes two relay lenses, i.e., a first relay lens 53 and a second relay lens 59, wherein the first relay lens 53 is between the first mirror 51 and the second mirror 55, and the second relay lens 59 is between the third mirror 57 and the light splitting element 80. The geometric center of the first relay lens 53 and the geometric center of the second relay lens 59 are both located on the reference plane 10, the geometric center of the first mirror 51, the geometric center of the second mirror 55, and the geometric center of the first relay lens 53 are located on the same straight line, and the line connecting the geometric center of the third mirror 57 and the geometric center of the second relay lens 59 is parallel to the first end 11. At this time, when the switching scanning element 30 is at the first working position 30a, the measurement light reflected by the switching scanning element 30 is reflected by the first reflecting mirror 51, transmitted by the first relay lens 53, reflected by the second reflecting mirror 55 and the third reflecting mirror 57 in sequence, transmitted by the second relay lens 59, and irradiated to the spectroscopic element 80.

As shown in fig. 2, in the present embodiment, when the switching scanning element 30 is at the first working position 30a, the light splitting element 80 receives the measurement light from the anterior ocular segment light path assembly 50, and the measurement light passes through the light splitting element 80 and is focused onto the anterior ocular segment of the eye E, such as the cornea of the eye E, via the objective lens 90. The anterior ocular segment scatters the measurement light to generate anterior ocular segment signal light, and the anterior ocular segment signal light is irradiated to the spectroscopic element 80 through the objective lens 90. The anterior ocular segment signal light is split into a first anterior ocular segment signal light and a second anterior ocular segment signal light by the light splitting element 80, and the second anterior ocular segment signal light is reflected by the light splitting element 80 to enter the posterior ocular segment light path component 70 and no longer propagates back to the main body module 100; the first anterior segment signal light propagates back to the main body module 100 through the light splitting element 80, the anterior segment light path assembly 50, and the switching scanning element 30 in the opposite direction to the measurement light, and interferes with the reference light in the coupler 103 to generate interference light, and the detector 105 receives and processes the interference light and transmits the interference light to the controller 111. Since the polarization direction of the first-eye front section signal light is controlled by the polarization controller 107 before returning to the coupler 103, the effect of interference is ensured.

In this embodiment, the posterior segment optical path assembly 70 includes a retroreflective element 71 and an optical element 73, and when the switching scanning element 30 is in the second working position 30b, the measurement light provided by the switching scanning element 30 is reflected by the retroreflective element 71 and the optical element 73 in sequence and then transmitted to the spectroscopic element 80.

Specifically, the optical element 73 may be a total reflection mirror, a half-transmission half-reflection mirror, or a dichroic mirror, and the intersection point of the system main optical axis L and the optical element 73 is located in the reference plane 10.

The retroreflective element 71 includes a first reflective surface and a second reflective surface. Referring again to fig. 3, the retroreflective elements 71 may be corner cubes, and preferably, the retroreflective elements 71 are right angle cubes. The right angle prism includes a first reflecting surface 71a and a second reflecting surface 71b, preferably, an included angle between the first reflecting surface 71a and the second reflecting surface 71b is set to be a right angle, and in other embodiments of the present invention, an included angle between the first reflecting surface 71a and the second reflecting surface 71b may be set to be an acute angle or an obtuse angle. The intersection point of the system main optical axis L and the second reflecting surface 71b is located in the reference plane 10, and a line connecting the intersection point of the system main optical axis L and the second reflecting surface 71b and the intersection point of the system main optical axis L and the first reflecting surface 71a is perpendicular to the reference plane 10. When the switching scanning element 30 is at the second working position 30b, the measurement light provided by the switching scanning element 30 is reflected by the first reflecting surface 71a, the second reflecting surface 71b and the optical element 73 in sequence and then transmitted to the spectroscopic element 80.

Referring to fig. 4, in other embodiments, the retroreflective element 71 may further be a mirror set, including a first mirror 71c and a second mirror 71d, where the reflecting surface of the first mirror 71c is a first reflecting surface, the reflecting surface of the second mirror 71d is a second reflecting surface, preferably, the reflecting surfaces of the first mirror 71c and the second mirror 71d are set to be right angles, and in other embodiments, the reflecting surfaces of the first mirror 71c and the second mirror 71d may also be set to be acute angles or obtuse angles. The intersection point of the system main optical axis L and the second mirror 71d is located in the reference plane 10, and the line connecting the intersection point of the system main optical axis L and the second mirror 71d and the intersection point of the system main optical axis L and the first mirror 71c is perpendicular to the reference plane 10. When the switching scanning element 30 is at the second working position 30b, the measurement light provided by the switching scanning element 30 is reflected by the first reflecting mirror 71c, the second reflecting mirror 71d and the optical element 73 in sequence and then transmitted to the spectroscopic element 80.

Preferably, the posterior segment optical path assembly 70 further includes a displacement control element (not shown), and the retroreflective element 71 is operable to adjust the optical path length. The retroreflective element 71 is fixed to the displacement control element and is movable with the displacement control element in a direction parallel to the first end 11 to change the optical path length that the measuring light experiences in the posterior segment optical path assembly 70. The posterior segment optical path assembly 70 further includes a refractive adjustment unit 75, where the refractive adjustment unit 75 is disposed between the optical element 73 and the optical splitting element 80, and the refractive adjustment unit 75 is movable between the optical element 73 and the optical splitting element 80, so that, for the examined eye E with different diopters, the measuring light can be focused on the posterior segment of the examined eye E, such as the retina of the examined eye E. During the movement, the intersection point of the system main optical axis L and the diopter adjustment unit 75 is always located on the reference plane 10. The diopter adjustment unit 75 may be a lens.

In measuring the posterior segment of the eye E, since the axial length of the eye E is different from one eye E to another, it is necessary to provide an optical path adjusting unit in one of the anterior segment optical path block 50 and the posterior segment optical path block 70, and it is preferable to provide an optical path adjusting unit, that is, the retroreflective element 71 in the posterior segment optical path block 70.

It will be appreciated that in other embodiments of the present invention, the displacement of the retroreflective element 71 may be calculated by a stepper motor, a voice coil motor, a grating ruler, a capacitive grating ruler, etc., and is not limited to the above-mentioned moving device or sensor, as long as the structure satisfying the design is within the scope of the present invention.

It will be appreciated that in other embodiments of the invention, the retroreflective element 71 may also be a movable retroreflector, and that the optical path adjustment may be achieved by simply moving the movable retroreflector.

In addition, in making posterior segment measurements, the location at which the measurement light is focused within the eye E may be adjusted by the refractive adjustment element 75, such as by moving the refractive adjustment element 75 to focus light on the retina of the eye E, to effect measurements of the eye E having myopia or hyperopia. Specifically, the refractive adjustment element 73 is fixed to a translation device (not shown) and its movement can be controlled manually or electrically to achieve refractive adjustment.

In this embodiment, after the measurement light is focused onto the posterior segment of the eye E, the posterior segment scatters the measurement light and generates posterior segment signal light, which is irradiated to the spectroscopic element 80 through the objective lens 90. The posterior segment signal light is split into a first posterior segment signal light and a second posterior segment signal light by the light splitting element 80, and the first posterior segment signal light is transmitted into the anterior segment optical path component 50 by the light splitting element 80 and does not propagate back to the main body module 100; the second posterior segment signal light is reflected by the light splitting element 80, propagates back to the main body module 100 through the posterior segment light path component 70 and the switching scanning element 30 in sequence along the direction opposite to the measuring light, interferes with the reference light in the coupler 103, generates interference light, and the detector 105 receives and processes the interference light and transmits the interference light to the controller 111. Since the polarization direction of the second posterior segment signal light is controlled by the polarization controller 107 before returning to the coupler 103, the effect of interference is ensured. The controller 111 obtains a parameter corresponding to the eye E, for example, an axial length of the eye E, by an optical path difference between the anterior segment imaging and the posterior segment imaging.

Here, the system main optical axis L is described along which measurement light may propagate from the body module 100 to the eye E, and it will be understood by those skilled in the art that the system main optical axis L passes through at least the centers of two spheres of at least one lens in the system, such as the centers of two spheres of the focus lens 109 or the centers of two spheres of the objective lens 90. Preferably, the system main optical axis L passes through at least the centers of two spheres of all lenses in the system, including the focusing lens 109, the first relay lens 53, the second relay lens 59, the refractive adjustment element 75, and the objective lens 90.

The emergent main optical axis L ₁ is a part of the main optical axis L of the system, the emergent main optical axis L ₁ is a straight line segment, and when the system is in a detection working condition, measurement light can enter the eye to be detected E through the emergent main optical axis L ₁.

In this embodiment, the switching scan element 30 may perform the scanning imaging of the eye E, in addition to the rapid switching of the optical path. The switching scanning element 30 is rotatable in the first working position 30a to scan the anterior segment of the eye E, and the switching scanning element 30 is rotatable in the second working position 30b to scan the posterior segment of the eye E.

Referring to fig. 5 (a) to 5 (b), the switching scan element 30 starts to rotate from the initial position 1, t ₁ is the working time required to scan the anterior segment or the posterior segment of the eye E, t ₂ is the time required to switch the switching scan element 30 from anterior segment imaging to posterior segment imaging, and t ₃ is the time required to return the switching scan element 30 to the initial position 1 after the posterior segment of the eye E is scanned. The "anterior segment scanning position" is a position where the switching scanning element 30 is in the first operating position 30a such that the measuring light is focused to the anterior segment of the eye E. The "posterior segment position" is a position where the switching scanning element 30 is in the second operating position 30b such that the measuring light is focused to the posterior segment of the eye E.

When an anterior ocular segment image is to be acquired, the switching scan element 30 is rotated within the first operating position 30a while the detector 105 simultaneously begins to acquire signals. When the time t ₁ passes, the switching scan element 30 is in position 2. After the detector 105 acquires the anterior ocular segment image, the switching scan element 30 is switched to the second working position 30b, and the time required for this process is t ₂, and the switching scan element 30 reaches position 3.

The acquisition of an image of the posterior segment of the eye is then initiated, and the switching scan element 30 is rotated within the second operating position 30b while the detector 105 simultaneously initiates the acquisition of signals. When the time t ₁ passes, the switching scan element 30 is in position 4. After the detector 105 acquires the posterior segment image, the switching scan element 30 rotates in the opposite direction to return to the initial position 1, and the time required for this process is t ₃, and the switching scan element 30 returns to the initial position 1.

In the embodiment of the present invention, the controller 111 controls the state change and the time of the switching scan element 30 and the detector 105.

Referring to fig. 2 again, in the present embodiment, the system further includes a fixation optical module 300, and the fixation optical module 300 includes a fixation light source 301 and a fixation lens 303. The light emitted by the fixation light source 301 is visible light, the fixation light source 301 is specifically a display screen, and the display screen may be an LCD screen, an OLED screen, an LED array screen, or the like, for displaying a fixation mark for fixation of the eye E.

Preferably, in this embodiment, the optical element 73 is a dichroic mirror. Specifically, the optical element 73 is transparent to the light output from the fixation light source 301 and reflects the light output from the light source 101.

The light emitted from the fixation light source 301 is transmitted through the fixation lens 303 and the optical element 73, is bent by the refraction adjusting element 75, is reflected by the light splitting element 80, and is focused by the objective lens 90 onto the posterior segment of the eye E, such as the retina of the eye E.

Specifically, in this embodiment, the fixation position of the eye E may be changed using a fixation mark that can be moved up and down, left and right, so as to satisfy detection of different positions of the eye. The diopter of the light emitted by the fixation light source 301 can be adjusted by the diopter adjusting element 75, if the light emitted by the fixation light source 301 cannot be adjusted, the sharpness of the fixation mark is different when the eye E with different vision is observed, which makes the eye feel uncomfortable when the eye is fixed, so that preferably, the optical path emitted by the fixation light source 301 focuses on the fundus retina of the eye E after being adjusted by the diopter adjusting element 75, so that the eye E can see the sharpness of the fixation mark.

As shown in fig. 2, the system provided in this embodiment further includes an anterior ocular segment imaging module 500 for capturing an image to determine parameters such as a central curvature of cornea, a pupil diameter, a white-to-white distance, and the like of the eye E to be inspected, for example, capturing an iris image of the eye E to be inspected. The anterior ocular segment imaging module 500 is electrically connected to the controller 111 and comprises: an illumination light source 501, a beam splitter 502, a magnifying lens 503, a third mirror 505, an imaging lens 507, and a camera 509.

Specifically, the illumination light source 501 is disposed between the objective lens 90 and the eye to be inspected E, and the illumination light source 501 emits near infrared light. The beam splitter 502 is specifically a dichroic mirror, and is capable of transmitting light output from the illumination light source 501 and reflecting light output from the light source 101 and light output from the fixation light source 301. The magnifying lens 503 is configured to converge the reflected light, and the imaging lens 507 is configured to image the reflected light on the camera 509.

The light emitted by the illumination light source 501 irradiates the anterior segment of the eye to be inspected E, and is reflected by the anterior segment to form reflected light, wherein a part of the light is reflected by the cornea of the eye to be inspected E, and a part of the light enters the eye to be inspected E through the cornea and is diffusely reflected by tissues such as the anterior chamber of the eye to be inspected E.

The reflected light is transmitted to the third reflecting mirror 505 through the objective lens 90, the spectroscope 502 and the magnifying lens 503, is reflected by the third reflecting mirror 505, passes through the image pickup lens 507, is focused by the image pickup lens 507 to the image pickup device 509 to form an image of the front section of the eye to be inspected, and the controller 111 collects the image of the front section of the eye to be inspected.

In order to make the subject feel comfortable, the contact lens 90 is set to protrude from the system so as to avoid a feeling of pressure caused by contact with the system, and thus the distance between the contact lens 90 and the camera 509 is large. In order to determine white-to-white distance, the anterior ocular segment imaging module 500 needs to have a large imaging range, which is contradictory to the anterior ocular segment 90 extension. The purpose of the magnifying lens 503 is to solve this contradiction, and the magnifying lens 503 can change the propagation directions of the light reflected by the cornea and the light diffusely reflected by the anterior chamber to converge and finally form a wide-range image on the camera 509.

Referring to fig. 6, in this embodiment, the illumination light source 501 includes a plurality of illumination lamps 501a, the plurality of illumination lamps 501a are uniformly distributed in an annular array, and when the system is in a cornea curvature measurement working condition, the geometric center of the annular shape formed by the illumination lamps 501a is aligned with the pupil center of the eye to be inspected E. Specifically, the illumination lamps 501a are LED lamps, and the number is 4 or more, and preferably, in the embodiment of the present invention, the number of illumination lamps 501a is 6.

When the system is in a cornea curvature measuring working condition, light emitted by the 6 illuminating lamps 501a irradiates on the cornea of the eye to be detected E, the light is reflected by the cornea, the reflected light passes through the anterior ocular segment imaging module 500 and is finally detected by the camera 509, and a distribution image of the 6 illuminating lamps 501a on the cornea is formed on the camera 509. In an embodiment of the invention, the distribution image is formed together with an image of the anterior segment of the eye to be inspected.

The controller 111 acquires images of the distribution of the 6 illumination lamps 501a on the cornea, processes the images using an algorithm installed therein, and obtains the cornea curvature of the eye E to be inspected, and in the embodiment of the present invention, the controller 111 obtains the cornea center curvature of the eye E to be inspected.

In this embodiment, the anterior ocular segment imaging module 500 further has a function of monitoring an optical path to guide an operator to operate an instrument and to know related information of a subject, the system is movably disposed on an operation table, a chin rest system is disposed on the operation table, the detector fixes the head of the subject by using the chin rest system to fix the subject's eye E, and after the fixation mark from the fixation optical module 300 is fixed in the subject's eye E, the detector controls the movement of the chin rest system and the ophthalmic measurement system by an operation lever while observing the display screen of the controller 111, so that the anterior ocular segment of the subject's eye E, such as an iris, enters the camera 509 of the anterior ocular segment imaging module 500, and an iris image is presented in the display screen of the controller 111, so as to guide a doctor to operate the instrument and know related information of the subject's eye E.

Example two

The first embodiment is a basic embodiment of the present invention, and for brevity, the first embodiment is the same as the first embodiment, and is not described in detail herein, and the first embodiment is incorporated by reference.

The ophthalmic measurement system provided in this embodiment is used to detect the eye E to be inspected, so as to determine parameters such as the axial length of the eye E to be inspected. Referring to fig. 7, the system includes a body module 2100, a reference plane 210, a switching scan element 230, an anterior ocular segment optical path assembly 250, a posterior ocular segment optical path assembly 270, and a spectroscopic element 280. Referring to fig. 8, the system preferably further includes an eye objective 290, a fixation optical module 2300, and an anterior ocular segment imaging module 2500.

In fig. 7, a dash-dot line indicates the system main optical axis L. When the system is in a detection working condition, the main body module 2100 generates reference light and provides measurement light to the switching scanning element 230, the measurement light is transmitted to the anterior ocular segment optical path assembly 250 or the posterior ocular segment optical path assembly 270 according to the rotation angle of the switching scanning element 230, and is focused to a corresponding part of the detected eye E through the objective lens 290 after being reflected or transmitted by the light splitting element 280, and then is scattered by the detected eye E to form signal light, the signal light propagates back to the main body module 2100 along a direction opposite to the measurement light and interferes with the reference light to generate interference light, and the main body module 2100 also collects the interference light.

The reference plane 210 is perpendicular to the line between the pupil centers of the left eye and the right eye of the eye to be inspected E when the system is in the inspection condition, the reference plane 210 comprises a first end 211, a second end 213 opposite to the first end 211 and parallel to the first end 211, a third end 215 perpendicular to the first end 211, and a fourth end 217 opposite to the third end 215 and parallel to the third end 215, the first end 211, the second end 213, the third end 215, and the fourth end 217 are connected end to form a closed rectangle, the first end 211 is close to the eye to be inspected E when the system is in the inspection condition and perpendicular to an emergent main optical axis L ₁, the third end 215 and the fourth end 217 are parallel to the emergent main optical axis L ₁ when the system is in the inspection condition, and the emergent main optical axis L ₁ is located in the reference plane 210 when the system is in the inspection condition.

It will be appreciated that the reference plane 210 is a virtual plane that describes the positional relationship of the various components in the system.

Referring to fig. 8, in the present embodiment, the main body module 2100 includes a light source 2101, a coupler 2103, a reference arm assembly 2130, a detector 2105, a polarization controller 2107, a focusing lens 2109 and a controller 2111. The reference arm assembly 2130 further includes a reference arm lens 2131 and a reference arm mirror 2133. The light source 2101 may be an OCT light source, which emits weak coherent light with a wavelength of near infrared and transmits the light to the coupler 2103, and the coupler 2103 splits the received light into two beams, wherein one beam is focused by the reference arm lens 2131 and reflected by the reference arm mirror 2133 and then returns to the coupler 2103 to be used as reference light. The other beam is sequentially focused by the polarization controller 2107 and the focusing lens 2109 and then transmitted to the switching scanning element 230 as measurement light.

Referring to fig. 9, the dashed line in fig. 9 illustrates the system principal optical axis L. In this embodiment, the switching scan element 230 is located outside the reference plane 210, and the switching scan element 30 is specifically a galvanometer. The switching scanning element 230 is rotatable about an axis 233, the axis 233 being parallel to the reference plane 210, and the axis 233 being parallel to said first end 211. The switching scan element 230 has a first working position 230a and a second working position 230b and is switchable between the first working position 230a and the second working position 230b by rotating about a fixed axis 233. The direction of propagation of the measurement light may be selected by controlling the switching scan element 230 to be at different angles of rotation so that the measurement light is delivered to either the anterior ocular segment optical path assembly 250 or the posterior ocular segment optical path assembly 270. Specifically, the switching scanning element 230 may be controlled to switch between the first working position 230a and the second working position 230b, when the switching scanning element 230 is in the first working position 230a, as shown in fig. 9, an included angle between a propagation path of incident light and a propagation path of reflected light at the switching scanning element 230 is β, and measurement light is transmitted to the anterior ocular segment optical path assembly 250; when the switching scan element 230 is in the second working position 230b, as shown in fig. 9, the included angle between the propagation path of the incident light and the propagation path of the reflected light at the switching scan element 230 is α, and the measurement light is transmitted to the posterior segment optical path component 270.

Specifically, in this embodiment, the system further includes an electronic control component (such as a motor), where the electronic control component has an electrically controlled rotating bracket (such as a rotating shaft), the electronic control component is electrically connected to the controller 2111, the switching scanning element 230 is fixed on the electrically controlled rotating bracket, and the controller 2111 controls the rotation of the electronic control component to drive the rotation of the electrically controlled rotating bracket so as to control the rotation angle of the switching scanning element 230, when the switching scanning element 230 rotates to the first working position 230a, the switching scanning element reflects the measurement light to the anterior ocular segment optical path component 250, and when the switching scanning element 230 rotates to the second working position, the switching scanning element reflects the measurement light to the posterior ocular segment optical path component 270.

It will be appreciated that in other embodiments of the present invention, the system may also control the angle of rotation of the switching scan element 230 by manual adjustment, in particular, the system includes a rotating bracket for fixing the switching scan element 230, the rotating bracket providing a knob by which the angle of rotation of the switching scan element 230 is adjusted manually to inject the measurement light into the corresponding position of the eye E to be inspected.

It is understood that in other embodiments of the present invention, the switching scan element 230 may also perform angular rotation control by other mechanical devices or electrical methods, and the design scheme meeting such design structure is within the scope of the present invention and will not be described herein.

Referring to fig. 8 again, in this embodiment, the measurement light reaches the light splitting element 280 after passing through the anterior ocular segment optical path assembly 250 or the posterior ocular segment optical path assembly 270, and the light splitting element 280 is specifically a half mirror, and can transmit the measurement light transmitted by the anterior ocular segment optical path assembly 250 and reflect the measurement light transmitted by the posterior ocular segment optical path assembly 270. Specifically, in the present embodiment, when the switching scan element 230 is at the first working position 230a, the measurement light passes through the spectroscopic element 280 and is focused onto the anterior ocular segment of the eye E, such as the cornea of the eye E, via the objective lens 290. When the switching scanning element 230 is at the second working position 230b, the measuring light is reflected by the light splitting element 280 and focused to the posterior segment of the eye E, such as the retina of the eye E, via the objective lens 290.

In this embodiment, the anterior ocular segment optical path assembly 250 includes at least one total reflection mirror, i.e., the first reflection mirror 251. When the switching scanning element 230 is in the first working position 230a, the measurement light transmitted by the switching scanning element 230 is reflected to the light splitting element 280 by the first mirror 251.

Preferably, the anterior ocular segment optical path assembly 250 comprises two total reflection mirrors, namely a first mirror 251 and a second mirror 255. The first mirror 251 is disposed at the second end 213, and the second mirror 255 is disposed at the first end 211. The intersection point of the system main optical axis L and the first mirror 251 and the intersection point of the system main optical axis L and the second mirror 255 are both located in the reference plane 210. The line of intersection of the system main optical axis L with the first mirror 251 and the intersection of the system main optical axis L with the second mirror 255 is parallel to the third end 215, and the line of intersection of the system main optical axis L with the second mirror 255 and the intersection of the system main optical axis L with the spectroscopic element 280 is parallel to the first end 211. When the switching scanning element 230 is in the first working position 230a, the light transmitted by the switching scanning element 230 is reflected to the light splitting element 280 through the first mirror 251 and the second mirror 255 in sequence.

It should be noted that, in this embodiment, the anterior ocular segment optical path assembly 250 further includes at least one relay lens, where there is at least one relay lens between the first mirror 251 and the second mirror 255, and when the switching scanning element 230 rotates to the first working position 230a, the first mirror 251 reflects the measurement light to the second mirror 255 through the relay lens; or at least one relay lens is provided between the second reflecting mirror 255 and the spectroscopic element 280, and the second reflecting mirror 255 reflects the measurement light to the spectroscopic element 280 through the relay lens.

Preferably, in the present embodiment, the anterior ocular segment optical path assembly 250 includes two relay lenses, namely a first relay lens 253 and a second relay lens 259, wherein the first relay lens 253 is between the first mirror 251 and the second mirror 255, and the second relay lens 259 is between the second mirror 255 and the light splitting element 280. The intersection point of the system main optical axis L and the first relay lens 253 and the intersection point of the system main optical axis L and the second relay lens 259 are all located in the reference plane 210, the intersection point of the system main optical axis L and the first mirror 251, the intersection point of the system main optical axis L and the second mirror 255, and the intersection point of the system main optical axis L and the first relay lens 253 are located in the same straight line, and the connection line of the intersection point of the system main optical axis L and the second mirror 255 and the intersection point of the system main optical axis L and the second relay lens 259 is parallel to the first end 211. At this time, when the switching scanning element 230 is at the first working position 230a, the measurement light reflected by the switching scanning element 230 is reflected by the first reflecting mirror 251, transmitted by the first relay lens 253, reflected by the second reflecting mirror 255, transmitted by the second relay lens 259, and irradiated to the spectroscopic element 280.

As shown in fig. 8, in the present embodiment, when the switching scanning element 230 is at the first working position 230a, the light splitting element 280 receives the measurement light from the anterior ocular segment light path assembly 250, and the measurement light passes through the light splitting element 280 and is focused onto the anterior ocular segment of the eye E, such as the cornea of the eye E, via the objective lens 290. The anterior ocular segment scatters the measurement light to generate anterior ocular segment signal light, and the anterior ocular segment signal light is irradiated to the spectroscopic element 280 through the objective lens 290. The anterior ocular segment signal light is split into a first anterior ocular segment signal light and a second anterior ocular segment signal light by the light splitting element 280, and the second anterior ocular segment signal light is reflected by the light splitting element 280 to enter the posterior ocular segment optical path component 270 and no longer propagates back to the main body module 2100; the first anterior segment signal light propagates back to the main body module 2100 through the light splitting element 280, the anterior segment optical path assembly 250, and the switching scanning element 230 in the opposite direction to the measurement light, and interferes with the reference light in the coupler 2103 to generate interference light, and the detector 2105 receives and processes the interference light and transmits the interference light to the controller 2111. Since the polarization direction of the first-eye front section signal light is controlled by the polarization controller 2107 before returning to the coupler 2103, the effect of interference is ensured.

In this embodiment, the posterior segment optical path assembly 270 includes a retroreflective element 271 and an optical element 273, and when the switching scanning element 230 is in the second working position 230b, the measurement light provided by the switching scanning element 230 is reflected by the retroreflective element 271 and the optical element 273 in sequence and then transmitted to the spectroscopic element 280.

Specifically, the optical element 273 may be a total reflection mirror, a half-transmission half-reflection mirror, or a dichroic mirror, and the geometric center of the optical element 273 is located on the reference plane 210.

The retroreflective element 271 includes a first reflective surface and a second reflective surface. Referring again to fig. 9, the retroreflective element 271 may be a corner cube prism, and preferably, the retroreflective element 271 is a corner cube prism. The right angle prism includes a first reflecting surface 271a and a second reflecting surface 271b, and an angle between the first reflecting surface 271a and the second reflecting surface 271b is preferably set to be a right angle, and in other embodiments of the present invention, an angle between the first reflecting surface 271a and the second reflecting surface 271b may be set to be an acute angle or an obtuse angle. The retroreflective element 271 and the switching scanning element 230 are disposed on opposite sides of the reference plane 210, and a line connecting an intersection point of the system main optical axis L and the first reflecting surface 271a and an intersection point of the system main optical axis L and the switching scanning element 230 is perpendicular to the reference plane 210, and a line connecting an intersection point of the system main optical axis L and the second reflecting surface 271b and an intersection point of the system main optical axis L and the optical element 273 is also perpendicular to the reference plane 210. When the switching scanning element 230 is at the second working position 230b, the measurement light provided by the switching scanning element 230 is reflected by the first reflecting surface 271a, the second reflecting surface 271b and the optical element 273 in sequence and then transmitted to the spectroscopic element 280.

Preferably, the posterior segment optical path assembly 270 further includes a displacement control element (not shown), and the retroreflective element 271 is operable to adjust the optical path length. The retroreflective element 271 is fixed to the displacement control element and is movable with the displacement control element in a direction perpendicular to the reference plane, thereby changing the optical path length that the measuring light undergoes in the posterior segment optical path assembly 270. The posterior segment optical path assembly 270 further includes a refractive adjustment unit 275, wherein the refractive adjustment unit 275 is disposed between the optical element 273 and the light splitting element 280, and the refractive adjustment unit 275 is movable between the optical element 273 and the light splitting element 280, so that for the examined eye E with different refractive powers, the measurement light can be focused on the posterior segment of the examined eye E, such as the retina of the examined eye E. During the movement, the intersection of the system principal optical axis L and the diopter adjustment unit 275 is always located in the reference plane 210. The diopter adjusting unit 275 may be a lens.

In measuring the posterior segment of the eye E, since the axial length of the eye E is different from one eye E to another, it is necessary to provide an optical path adjusting unit in one of the anterior segment optical path block 250 and the posterior segment optical path block 270, and preferably, the optical path adjusting unit, that is, the retroreflective element 271 is provided in the posterior segment optical path block 270.

It will be appreciated that in other embodiments of the present invention, the displacement of the retroreflective element 271 may be calculated by a stepper motor, a voice coil motor, a grating ruler, a capacitive grating ruler, or the like, and is not limited to the above-mentioned mobile device or sensor, as long as the structure satisfying such design is within the scope of the present invention.

It will be appreciated that in other embodiments of the present invention, the retroreflective element 271 may also be a movable retroreflector, and that the optical path adjustment may be achieved by simply moving the movable retroreflector.

In addition, in making posterior segment measurements, the location at which the measurement light is focused within the eye E may be adjusted by the refractive adjustment element 275, such as by moving the refractive adjustment element 275 to focus light on the retina of the eye E to effect measurements of the eye E having myopia or hyperopia. Specifically, the refractive adjustment element 275 is fixed to a translation device (not shown) and its movement can be controlled manually or electrically to achieve refractive adjustment.

In this embodiment, after the measurement light is focused onto the posterior segment of the eye E, the posterior segment scatters the measurement light and generates posterior segment signal light, and the posterior segment signal light irradiates the spectroscopic element 280 through the objective lens 290. The posterior segment signal light is split into a first posterior segment signal light and a second posterior segment signal light by the light splitting element 280, and the first posterior segment signal light is transmitted into the anterior segment optical path component 250 by the light splitting element 280 and is not transmitted back to the main body module 2100; the second posterior segment signal light is reflected by the light splitting element 280, and then propagates back to the main body module 2100 through the posterior segment optical path component 270 and the switching scanning element 230 in the opposite direction to the measurement light, and interferes with the reference light in the coupler 2103 to generate interference light, and the detector 2105 receives and processes the interference light and transmits the interference light to the controller 2111. Since the polarization direction of the second posterior segment signal light is controlled by the polarization controller 2107 before returning to the coupler 2103, the effect of interference is ensured.

It will be appreciated that the system can obtain relevant parameters of the subject eye E, such as the axial length of the subject eye E, by controlling the angle of rotation of the switching scan element 230 to rapidly switch between imaging the anterior segment of the eye or imaging the posterior segment of the eye E, and by calculating the optical path difference between imaging the anterior segment of the eye and imaging the posterior segment of the eye.

Referring to fig. 8 again, in this embodiment, the system further includes a fixation optical module 2300, and the fixation optical module 2300 includes a fixation light source 2301 and a fixation lens 2303. The light emitted by the fixation light source 2301 is visible light, the fixation light source 2301 is specifically a display screen, and the display screen may be an LCD screen, an OLED screen, an LED array screen, or the like, for displaying a fixation mark for fixation of the eye E.

Preferably, in the present embodiment, the optical element 273 is a dichroic mirror. Specifically, the optical element 273 transmits light output from the fixation light source 2301 and reflects light output from the light source 2101.

The light emitted from the fixation light source 2301 is transmitted through the fixation lens 2303 and the optical element 273, is bent by the refraction adjusting element 275, is reflected by the light splitting element 280, and is focused on the posterior segment of the eye E, such as the retina of the eye E, by the objective lens 290.

Specifically, in this embodiment, the fixation position of the eye E may be changed using a fixation mark that can be moved up and down, left and right, so as to satisfy detection of different positions of the eye. The diopter of the light emitted by the fixation light source 2301 can be adjusted by the diopter adjusting element 275, if the diopter of the light emitted by the fixation light source 2301 cannot be adjusted, the sharpness of the fixation mark is different when the eye E with different vision is observed, which makes the eye E feel uncomfortable when the eye E is fixed, so that preferably, the optical path emitted by the fixation light source 2301 focuses on the retina of the fundus of the eye E after being adjusted by the diopter adjusting element 275, so that the eye E can see the sharpness of the fixation mark.

As shown in fig. 8, the system provided in this embodiment further includes an anterior ocular segment imaging module 2500 for capturing an image to determine parameters such as a central curvature of cornea, a pupil diameter, a white-to-white distance, and the like of the eye E to be inspected, for example, capturing an iris image of the eye E to be inspected. The anterior ocular segment imaging module 2500 is electrically coupled to the controller 2111 and comprises: an illumination light source 2501, a beam splitter 2502, a magnifying lens 2503, a third mirror 2505, an imaging lens 2507, and an imaging device 2509.

Specifically, the illumination light source 2501 is disposed between the objective lens 290 and the eye to be inspected E, and the illumination light source 2501 emits near infrared light. The beam splitter 2502 is specifically a dichroic mirror, and transmits light output from the illumination light source 2501 and reflects light output from the light source 2101 and light output from the fixation light source 2301. The magnifying lens 2503 is configured to converge the reflected light, and the imaging lens 2507 is configured to image the reflected light on the camera 2509.

The light emitted from the illumination light source 2501 irradiates the anterior ocular segment of the eye E, and is reflected by the anterior ocular segment to form reflected light, wherein a part of the light is reflected by the cornea of the eye E, and a part of the light enters the eye E through the cornea and is diffusely reflected by tissues such as the anterior chamber of the eye E.

The reflected light is transmitted to the third mirror 2505 through the objective lens 290, the beam splitter 2502 and the magnifying lens 2503, is reflected by the third mirror 2505, passes through the image pickup lens 2507, and is focused by the image pickup lens 2507 to the image pickup device 2509 to form an image of the front section of the eye to be inspected, and the controller 2111 collects the image of the front section of the eye to be inspected.

In order to make the subject feel comfortable, the contact lens 290 is provided so as to protrude from the system, so that the distance between the contact lens 290 and the camera 2509 is large. In order to determine white-to-white distance, the anterior ocular segment imaging module 2500 needs to have a large imaging range, which is in contradiction with the anterior ocular objective 290 extension. The purpose of the magnifying lens 2503 is to solve this contradiction, and the magnifying lens 2503 can change the propagation directions of the light reflected by the cornea and the light diffusely reflected by the anterior chamber so as to converge, and finally form an image of a wide range on the camera 2509.

In this embodiment, the anterior ocular segment imaging module 2500 further has a function of monitoring an optical path to guide an operator to operate an instrument and to understand related information of a subject, the system is movably disposed on an operation table, a chin rest system is disposed on the operation table, the detector fixes the head of the subject by using the chin rest system to fix the subject's eye E, and after the fixation target from the fixation optical module 2300 is fixed in the subject's eye E, the detector controls the movement of the chin rest system and the ophthalmic measurement system by an operation lever while observing the display screen of the controller 2111, so that the anterior ocular segment of the subject's eye E, such as an iris, enters the camera 2509 of the anterior ocular segment imaging module 2500, and an iris image is presented in the display screen of the controller 2111, so as to guide a doctor to operate the instrument and understand related information of the subject's eye E.

In summary, in the ophthalmic measurement system provided by the embodiment of the present invention, the rotation angle of the switching scanning element is controlled to rapidly switch the anterior ocular segment imaging or the posterior ocular segment imaging of the eye to be inspected, and the optical path difference between the anterior ocular segment imaging and the posterior ocular segment imaging is calculated to obtain the relevant parameters of the eye to be inspected; and the switching scanning element also has a scanning function, so that the scanning of the anterior segment and the posterior segment of the eye to be inspected can be realized. Compared with the prior art, the invention provides another technical scheme capable of realizing the switching of the scanning of the front section and the back section of the eye to be inspected so as to determine the axial length of the eye to be inspected based on the spectral domain OCT technology, and meanwhile, the defects of complex structure and high cost of the prior art can be overcome.

Furthermore, the ophthalmic measuring system provided by the embodiment of the invention has the advantages that the anterior ocular segment optical path component and the posterior ocular segment optical path component are both positioned on the reference plane, the vertical arrangement of the optical path structure can be realized, the appearance of the ophthalmic measuring system is attractive, the ophthalmic measuring system accords with the ergonomics, and the pressing sense of a tested patient is avoided. On the basis, the switching scanning element can rotate around a certain axis to realize anterior ocular segment scanning and posterior ocular segment scanning and switch between anterior ocular segment scanning and posterior ocular segment scanning, so that the inspected eye can be scanned in the horizontal direction, and the horizontal scanning ensures that the measuring light beam is less prone to shielding of eyelid and eyelashes.

It will be appreciated that a horizontal scan, i.e. a scan plane perpendicular to the reference plane, is taken across the left and right eye links of the human eye under test.

If the left and right direction of the system testee is large, both eyes of the testee are shielded by the instrument probe, and when the working distance of the instrument probe is short, both eyes of the testee are shielded by near objects, so that a strong pressed feeling is generated, and the measurement experience of the testee is not facilitated.

Claims

1. An ophthalmic measuring system for detecting an eye to be inspected is characterized by comprising a main body module reference plane, a switching scanning element, an anterior segment optical path component, a posterior segment optical path component, a beam splitting element and a system main optical axis,

The main body module is used for providing measuring light and reference light, receiving first anterior ocular segment signal light and second posterior ocular segment signal light, interfering the first anterior ocular segment signal light and the second posterior ocular segment signal light with the reference light respectively, and collecting corresponding interference light;

The system main optical axis comprises an emergent main optical axis, the emergent main optical axis is positioned on the reference plane, the switching scanning element can rotate around a certain axis, and the switching scanning element is provided with a first working position and a second working position and can be switched between the first working position and the second working position by rotating around the fixed axis;

The anterior ocular segment optical path component comprises a first reflecting mirror, the posterior ocular segment optical path component comprises a retroreflection element and an optical element, and the intersection point of the system main optical axis and the first reflecting mirror and the intersection point of the system main optical axis and the optical element are both positioned on the reference plane;

When the switching scanning element is in the first working position, the measuring light provided by the main body module is reflected to the first reflector by the switching scanning element, reflected to the light splitting element by the first reflector, conducted to the inspected eye by the light splitting element, scattered by the front eye of the inspected eye to form front eye section signal light, scattered to the light splitting element by the front eye section of the inspected eye, the light splitting element divides the front eye section signal light into the first front eye section signal light and the second front eye section signal light, conducts the first front eye section signal light to the first reflector, reflects to the switching scanning element by the first reflector and enters the main body module by the switching scanning element, when the switching scanning element is in the second working position, the measuring light provided by the main body module is reflected to the retroflection element by the switching scanning element, reflected to the optical element by the retroflection element, reflected to the light splitting element by the optical element, transmitted to the inspected eye by the light splitting element, scattered by the posterior segment of the inspected eye to form posterior segment signal light, the posterior segment signal light is scattered to the light splitting element by the posterior segment of the inspected eye, the light splitting element divides the posterior segment signal light into first posterior segment signal light and second posterior segment signal light, and transmits the second posterior segment signal light to the optical element, the second posterior segment signal light is reflected to the retroflection element by the optical element, and then reflected by the retroreflective element to the switching scanning element and reflected by the switching scanning element into the main body module.

2. The system of claim 1, wherein the switching scan element is rotatable about the fixed axis in the first operating position, the switching scan element is rotatable about the fixed axis in the first operating position to effect scanning of the anterior ocular segment of the subject's eye, the switching scan element is rotatable about the fixed axis in the second operating position, and the switching scan element is rotatable about the fixed axis in the second operating position to effect scanning of the posterior ocular segment of the subject's eye.

3. The system of claim 2, wherein the fixed axis is parallel to the exit primary optical axis when the system is in a detection condition.

4. The system of claim 3, wherein the retroreflective element comprises a first reflective surface and a second reflective surface, an intersection of the system primary optical axis and the second reflective surface being located at the reference plane, and wherein when the switching scanning element is in the second operating position, measurement light is reflected by the switching scanning element to the first reflective surface and then reflected by the first reflective surface and the second reflective surface to the optical element.

5. The system of claim 4, wherein the anterior ocular segment optical path assembly comprises a second mirror, the second reflective surface, the optical element, the first mirror, the switching scan element, and the second mirror being sequentially disposed in a direction perpendicular to the exit primary optical axis,

When the switching scanning element is in the first working position, the measuring light provided by the main body module is reflected to the first reflecting mirror by the switching scanning element, reflected to the second reflecting mirror by the first reflecting mirror, and reflected to the light splitting element by the second reflecting mirror.

6. The system of claim 5, wherein the anterior ocular segment optical path assembly comprises a third mirror, a line connecting an intersection of the system primary optical axis with the first mirror and an intersection of the system primary optical axis with the second mirror is perpendicular to the exit primary optical axis, a line connecting an intersection of the system primary optical axis with the second mirror, and an intersection of the system primary optical axis with the third mirror is parallel to the exit primary optical axis, a line connecting an intersection of the system primary optical axis with the third mirror and an intersection of the system primary optical axis with the light splitting element is perpendicular to the exit primary optical axis,

When the switching scanning element is in the first working position, the measuring light provided by the main body module is reflected to the first reflecting mirror by the switching scanning element, reflected to the second reflecting mirror by the first reflecting mirror, reflected to the third reflecting mirror by the second reflecting mirror, and reflected to the light splitting element by the third reflecting mirror.

7. The system of claim 4, wherein the retroreflective element is movable in a direction perpendicular to the exit primary optical axis.

8. The system of claim 2, wherein the switching scan element is located outside of the reference plane, the fixed axis being parallel to the reference plane and perpendicular to the exit primary optical axis.

9. The system of claim 8, wherein the retroreflective element includes a first reflective surface and a second reflective surface, the line connecting the intersection of the system primary optical axis and the switching scan element and the intersection of the system primary optical axis and the first reflective surface is perpendicular to the reference plane, the line connecting the intersection of the system primary optical axis and the second reflective surface and the intersection of the system primary optical axis and the optical element is also perpendicular to the reference plane, and when the switching scan element is in the second operating position, the measurement light is reflected by the switching scan element to the first reflective surface and then reflected by the first reflective surface and the second reflective surface to the optical element.

10. The system of claim 9, wherein the anterior ocular segment optical path assembly comprises a second mirror, the intersection of the system primary optical axis with the first mirror and the intersection of the system primary optical axis with the second mirror are connected to be parallel to the exit primary optical axis, the intersection of the system primary optical axis with the second mirror and the intersection of the system primary optical axis with the beam splitting element are connected to be perpendicular to the exit primary optical axis,

11. The system of claim 9, wherein the retroreflective element is movable in a direction perpendicular to the reference plane.

12. The system of claim 1, wherein the reference plane is perpendicular to a line connecting centers of pupils of left and right eyes of the eye to be inspected when the system is in a test condition.

13. The system of claim 1, wherein the system includes a scan plane, the scan plane is perpendicular to the reference plane, the exit primary optical axis is located in the scan plane, a line connecting centers of pupils of left and right eyes of the eye to be inspected is located in the scan plane when the system is in the inspection condition, and paths of the measurement light transmitted to the eye to be inspected through the beam splitting element are all located in the scan plane.