CN108371542A - A kind of eyeground multi-modal synchronization imaging system - Google Patents

Abstract

Multi-modal synchronization imaging system in eyeground provided by the invention, by the way that line scanning fast imaging techniques and Optical Coherence Tomography Imaging Technology are combined, system hardware is effectively reduced using total light path resonant mirror synchronous scanning imaging method, and the scanning of optical coherence tomography is not influenced while solving lens and corneal reflection speck using hollow slots speculum, it realizes efficiently using for optical coherence tomography and line cofocus scanning speed, achievees the purpose that the imaging of quick face and the fault imaging of eye ground.

Description

A fundus multi-modal synchronous imaging system

technical field

The invention relates to an optical imaging and biomedical diagnostic equipment, in particular to a fundus multi-mode synchronous imaging system.

Background technique

At present, there are a variety of fundus retinal imaging technologies clinically, including fundus camera, optical coherence tomography, confocal scanning technology, etc., which play an important role in biological research and disease diagnosis.

The high-resolution imaging method of laser confocal scanning ophthalmoscope that filters out stray light through conjugate apertures has been extensively studied and successfully applied to biological research and medical diagnosis, including ophthalmology imaging. On the basis of confocal scanning, the conjugate hole is changed to a conjugate slit. Although part of the imaging resolution is sacrificed, the imaging speed is greatly improved. Compared with the fundus camera exposed by strong light flicker, high-speed real-time imaging of the fundus can be achieved. .

Patent application CN104224109A discloses a fundus camera combined with an OCT system, which combines the fundus camera with optical coherence tomography technology, but because the fundus camera uses flicker exposure, the strong light will greatly stimulate the eyes and cannot continue imaging; Patent application CN104684457A discloses two-dimensional confocal imaging using an OCT light source and scanning optics, using the sample light taken by optical coherence tomography as the imaging light for confocal imaging, but laser confocal scanning imaging is horizontal scanning, optical coherence Tomography is longitudinal tomography, and the speed in the transverse direction is very slow, which will greatly affect the speed of confocal imaging.

Contents of the invention

In view of this, it is necessary to provide a fundus multi-modal synchronous imaging system, which can realize the effective utilization of optical coherence tomography and line confocal scanning speed by combining line scanning fast imaging technology and optical coherence tomography technology, To achieve the purpose of rapid surface imaging and tomographic imaging of the fundus retina.

To achieve the above object, the present invention adopts the following technical solutions:

On the one hand, the fundus multi-modal synchronous imaging system provided by the present invention includes an optical coherence tomography module, a slow-axis scanning module, an imaging module, a hollow slit mirror, a line-scanning confocal illumination module, a fast-axis scanning module, and an imaging module. Objective lens, the optical coherence tomography module is used to form optical coherence tomography sample light, the slow axis scanning module includes a slow axis scanning galvanometer and a slow axis focusing lens, and the imaging module includes a focusing lens, a beam splitter and a detection device, the line-scan confocal illumination module includes a laser, a first collimator, and a cylindrical mirror, and the fast-axis scanning module includes a fast-axis scanning galvanometer and a scanning lens; wherein:

The optical coherence tomography sample light is collimated by a collimator and then enters the slow-axis scanning galvanometer, and then enters the beam splitter after passing through the slow-axis focusing lens, and the sample light reflected by the beam splitter passing through the slit of the hollow slit reflector after being focused by the focusing lens;

The laser beam emitted by the laser enters the hollow slit reflector after passing through the first collimator and the cylindrical mirror in turn, and the laser beam is reflected by the hollow slit reflector and passes through the The optical coherence tomography sample light of the slit of the hollow slit mirror is combined to form combined light;

The combined light passes through the fast-axis scanning galvanometer, the scanning lens and the objective lens to perform synchronous illumination and imaging of the fundus, and the formed imaging light passes through the objective lens, the scanning lens, and the eyepiece successively after being reflected by the retina of the fundus. The fast-axis scanning galvanometer and the slit of the hollow slit mirror enter the focusing lens, and after being focused by the focusing lens, the imaging light transmitted by the beam splitter is received and imaged by the detector The imaging light that is focused by the focusing lens and then reflected by the beam splitter passes through the slow-axis focusing lens and the slow-axis scanning galvanometer in order to form interference images in the optical coherence tomography module.

In some preferred embodiments, the optical coherence tomography module is a swept source optical coherence tomography unit or a spectral domain optical coherence tomography unit.

In some preferred embodiments, the slow-axis focusing lens in the slow-axis scanning module and the focusing lens in the imaging module form a 4f system.

In some preferred embodiments, the slow-axis scanning galvanometer and the fast-axis scanning galvanometer are in conjugate positions.

In some preferred embodiments, after the optical coherence tomography sample light is scanned by the slow-axis scanning galvanometer, the scanning trajectory of the hollow slit mirror is in the same direction as the slit.

In some preferred embodiments, the beam splitter is a beam splitter plate, a beam splitter prism, or a beam splitter film.

In some preferred embodiments, the hollow slit reflector is a glass sheet coated with a slit reflective film or a reflector cut with a slit.

In some preferred embodiments, the non-converging direction of the cylindrical mirror is perpendicular to the slit direction of the hollow slit mirror, and the center of the fast-axis scanning galvanometer is located at the focal point of the cylindrical mirror.

In some preferred embodiments, the hollow slit reflector is a glass sheet coated with a slit reflective film or a reflector cut with a slit.

The present invention adopts above-mentioned technical scheme, can realize following beneficial effect:

In the fundus multi-modal synchronous imaging system provided by the present invention, the optical coherence tomography sample light is collimated by the first collimator and then enters the slow-axis scanning galvanometer, and then enters the slow-axis focusing lens. The beam splitter, the sample light reflected by the beam splitter is focused by the focusing lens and then passes through the slit of the hollow slit mirror; the laser beam emitted by the laser passes through the collimator, the After the cylinder mirror enters the hollow slit reflector, the laser beam is reflected by the hollow slit reflector and combined with the sample light passing through the slit of the hollow slit reflector to form combined light; The combined light passes through the fast-axis scanning galvanometer, the scanning lens and the objective lens to perform synchronous illumination and imaging of the fundus, and the formed imaging light passes through the objective lens, the scanning lens, and the eyepiece successively after being reflected by the retina of the fundus. The fast-axis scanning galvanometer and the slit of the hollow slit mirror enter the focusing lens, and after being focused by the focusing lens, the imaging light transmitted by the beam splitter is received and imaged by the detector After being focused by the focusing lens, the imaging light reflected by the beam splitter passes through the slow-axis focusing lens and the slow-axis scanning galvanometer in sequence in the optical coherence tomography module for interference imaging. The fundus provided by the present invention Multi-modal synchronous imaging system, through the combination of line-scanning fast imaging technology and optical coherence tomography technology, adopts the common optical path resonant mirror synchronous scanning imaging method to effectively reduce the system hardware, and uses the hollow slit mirror to solve the reflection of the lens and cornea The bright spot does not affect the scanning of optical coherence tomography, realizes the effective use of optical coherence tomography and line confocal scanning speed, and achieves the purpose of rapid surface imaging and tomographic imaging of fundus retina.

Description of drawings

FIG. 1 is a schematic structural diagram of a fundus multi-modal synchronous imaging system provided in this embodiment.

FIG. 2 is a schematic structural diagram of a fundus multi-modal synchronous imaging system provided by Embodiment 1 of the present invention.

FIG. 3 shows two typical hollow slit reflectors provided by Embodiment 1 of the present invention.

FIG. 4 is a schematic diagram of the relationship between the slow-axis scanning beam trajectory and the slit provided by Embodiment 1 of the present invention.

FIG. 5 is a schematic structural diagram of a fundus multi-modal synchronous imaging system provided by Embodiment 2 of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Please refer to Fig. 1, the fundus multi-modal synchronous imaging system provided by the embodiment of the present invention includes: a line scanning confocal illumination module 1, a slow axis scanning module 2, an optical coherence tomography module 3, a fast axis scanning module 4, a hollow A slit mirror 5, an imaging module 6, an objective lens 7 and a fundus retina 8. in:

The optical coherence tomography module 3 is used to form optical coherence tomography sample light. The slow-axis scanning module 2 includes a slow-axis scanning galvanometer 21 and a slow-axis focusing lens 22 . The imaging module 6 includes a focusing lens 61 , a beam splitter 62 and a detector 63 . The line scan confocal illumination module 1 includes a laser 11 , a first collimator 12 and a lenticular lens 13 . The fast-axis scanning module 4 includes a fast-axis scanning galvanometer 41 and a scanning lens 42 .

The fundus multimodal synchronous imaging system provided by the present invention works in the following manner:

The optical coherence tomography sample light is collimated by a collimator and then enters the slow-axis scanning galvanometer 21, then passes through the slow-axis focusing lens 22 and then enters the beam splitter 62, and is reflected by the beam splitter 62 After the sample light is focused by the focusing lens 61, it passes through the slit of the hollow slit mirror 5;

The laser beam emitted by the laser 11 enters the hollow slit reflector 5 after passing through the first collimator 12 and the cylinder lens 13 in turn, and the laser beam is reflected by the hollow slit reflector 5 combined with the sample light passing through the slit of the hollow slit mirror 5 to form combined light;

The combined light passes through the fast-axis scanning galvanometer 41, the scanning lens 42, and the objective lens 7 to perform synchronous illumination and imaging on the fundus, and the formed imaging light passes through the objective lens 7, the objective lens 7, and the eye lens successively after being reflected by the retina 8 of the fundus. The scanning lens 42, the fast-axis scanning galvanometer 41, and the slit of the hollow slit reflector 5 enter the focusing lens 61, and are transmitted through the beam splitter 62 after being focused by the focusing lens 61. The imaging light is received and imaged by the detector 63, and after being focused by the focusing lens 61, the imaging light reflected by the beam splitter 62 passes through the slow axis focusing lens 22 and the slow axis scanning galvanometer 21 in turn. Interferometric imaging in the optical coherence tomography module 3 .

It can be understood that the fundus multi-modal synchronous imaging system provided by the present invention combines the line scanning fast imaging technology with the optical coherence tomography technology, adopts the common optical path resonant mirror synchronous scanning imaging method to effectively reduce the system hardware, and adopts the hollow narrow The slit mirror solves the bright spots reflected by the lens and cornea without affecting the scanning of optical coherence tomography, realizes the effective use of optical coherence tomography and line confocal scanning speed, and achieves the purpose of rapid surface imaging and tomographic imaging of the fundus retina.

Example 1

Please refer to FIG. 2 , which is a schematic structural diagram of a fundus multi-modal synchronous imaging system provided by Embodiment 1 of the present invention.

In this embodiment, the optical coherence tomography module 3 is a swept source optical coherence tomography unit, including: a light source 311, a first coupler 312, a second collimator 313, a compensating mirror 316, a right-angle reflecting prism 317, a second Three collimators 315 , a second coupler 318 and a balanced detector 319 .

Specifically, the light emitted by the light source 311 of optical coherence tomography passes through the first coupler 312 and is divided into two parts of light beams, one of which passes through the collimator 314 and exits through the compensating mirror 316 and the right-angle reflective prism 317, and then is collimated by the collimator 316 Received, and reach the second coupler 318 as reference light; another part of the light reaches the collimator 313 from the first coupler 312 as the optical coherence tomography sample light, and enters the slow axis scanning after exiting the collimator 313 The vibrating mirror 21 is incident on the beam splitter 62 after passing through the slow axis focusing lens 22, and the sample light reflected by the beam splitting mirror 62 is focused by the focusing lens 61 and passes through the hollow slit mirror 5 the slit.

The laser beam emitted by the laser 11 enters the hollow slit reflector 5 after passing through the first collimator 12 and the cylinder lens 13 in turn, and the laser beam is reflected by the hollow slit reflector 5 combined with the sample light passing through the slit of the hollow slit mirror 5 to form combined light;

The combined light passes through the fast-axis scanning galvanometer 41, the scanning lens 42, and the objective lens 7 to perform synchronous illumination and imaging on the fundus, and the formed imaging light passes through the objective lens 7, the objective lens 7, and the eye lens successively after being reflected by the retina 8 of the fundus. The scanning lens 42, the fast-axis scanning galvanometer 41, and the slit of the hollow slit reflector 5 enter the focusing lens 61, and are transmitted through the beam splitter 62 after being focused by the focusing lens 61. The imaging light is received and imaged by the detector 63 .

It can be understood that the imaging light reflected by the beam splitter 62 after being focused by the focusing lens 61 passes through the slow axis focusing lens 22, the slow axis scanning galvanometer 21, is received by the collimator 313, and then passes through the first Most of the light coupled by the coupler 312 enters the second coupler 318 , interferes with the reference light for imaging, and is finally received and imaged by the balanced detector 319 .

In some preferred embodiments, the type of the swept source optical coherence tomography unit of the swept source is santec-HSL-10, the sweep speed is 100 kHz, and the center wavelength is 1060 nm. It can be understood that the frequency-sweeping light source model, frequency-sweeping speed and central wavelength of the optical coherence tomography unit of the frequency-sweeping source are not limited to the above settings, and can be adjusted according to actual conditions in practice.

It can be understood that, after the light emitted by the frequency-sweeping light source 311 passes through the coupler 322 and the first coupler 312, 80% of the light passes through the second collimator 313, the compensating mirror 316, and the right-angle reflective prism 317, and then is again filtered by the third collimator. 315, another 20% of the light reaches the collimator 313 as sample light.

In some preferred embodiments, the scanning speed of the fast-axis scanning galvanometer is 200 Hz, and the size of the mirror is 10 mm×15 mm. It can be understood that, in practice, the scanning speed and mirror size of the fast-axis scanning galvanometer can be adjusted according to actual conditions.

The scanning speed set by the slow-axis scanning galvanometer is 0.5 Hz, the model is the same as that of the fast-axis scanning galvanometer, both are Cambridge 6220H, and the directions of the scanning axes are perpendicular to each other. It can be understood that the model of the slow-axis scanning galvanometer is not limited to the above model, and can also be adjusted according to actual conditions in practice.

In some preferred embodiments, the slow-axis focusing lens 22 and the focusing lens 61 constitute a 4f system, and both the slow-axis scanning galvanometer and the fast-axis scanning galvanometer are located at the lens focus position of the 4f system.

In some preferred embodiments, the laser 11 of the line-scanning confocal illumination module 1 emits 650nm light, passes through the collimator 142 and becomes a parallel light spot with a diameter of 20mm, and is again captured by a cylindrical lens with a focal length of 40mm 13 is converged into a line beam, the direction of beam convergence is parallel to the direction of the slit, the light along the optical axis passes through the slit, and most of the light not on the optical axis is reflected by the hollow slit reflector.

Please refer to Fig. 3, the hollow slit reflector 5 is a glass plate coated with a slit reflective film (left figure) or a reflector (right figure) with a slit cut out, preferably, the hollow slit reflector is coated with There are glass sheets with slit reflective film.

Please refer to FIG. 4 , after the sample light of optical coherence tomography is scanned by the slow-axis scanning galvanometer 21 , it passes through the slit of the hollow slit mirror 5 , and the scanning direction is consistent with the direction of the slit.

In some preferred embodiments, the beam splitter 62 is a beam splitter plate, a beam splitter prism, or a beam splitter film. Preferably, the model of the spectroscope is thorlabsDMSP805, with a short pass and a cut-off wavelength of 805 nm.

In some preferred embodiments, the model of the detector 63 is E2V-EM4, 512pixels, and the maximum sampling speed is 210kHz.

The fundus multi-modal synchronous imaging system provided by the above-mentioned embodiments of the present invention combines line-scan rapid imaging technology with optical coherence tomography technology, adopts a common optical path resonant mirror synchronous scanning imaging method to effectively reduce system hardware, and adopts hollow narrow The slit mirror solves the bright spots reflected by the lens and cornea without affecting the scanning of optical coherence tomography, realizes the effective use of optical coherence tomography and line confocal scanning speed, and achieves the purpose of rapid surface imaging and tomographic imaging of the fundus retina.

Example 2

Please refer to FIG. 5 , which is a schematic structural diagram of a fundus multi-modal synchronous imaging system provided by Embodiment 2 of the present invention.

In this embodiment, the optical coherence tomography module 3 is a spectral domain optical coherence tomography unit, including a semiconductor laser 321, a coupler 322, a collimator 328, a compensation mirror 325, a plane mirror 326, a collimator 327, a collimator Straight mirror 328 , grating 329 , focusing lens 330 and line camera 331 .

The light source of the spectral domain optical coherence tomography unit is a semiconductor laser 321, the model is SLD-351, the center wavelength is 830nm, and the bandwidth is 80nm.

It can be understood that after the light emitted by the semiconductor laser 321 passes through the coupler 322, 80% of the light passes through the collimator 324, the compensating mirror 325, and is received by the collimator 324 again after being reflected by the plane reflector 326; The light reaches the collimator 323 as sample light, and is incident on the slow-axis scanning galvanometer 21 after exiting the collimator 323, and then enters the beam splitter 62 after passing through the slow-axis focusing lens 22, and passes through the beam splitter The sample light reflected by 62 is focused by the focusing lens 61 and then passes through the slit of the hollow slit mirror 5 .

The laser beam emitted by the laser 11 enters the hollow slit reflector 5 after passing through the collimator 12 and the cylinder lens 13 in turn, and the laser beam is reflected by the hollow slit reflector 5 and then merges with the transparent slit reflector 5. The sample light passing through the slit of the hollow slit mirror 5 is combined to form combined light;

The combined light passes through the fast-axis scanning galvanometer 41, the scanning lens 42, and the objective lens 7 to perform synchronous illumination and imaging on the fundus, and the formed imaging light passes through the objective lens 7, the objective lens 7, and the eye lens successively after being reflected by the retina 8 of the fundus. The scanning lens 42, the fast-axis scanning galvanometer 41, and the slit of the hollow slit reflector 5 enter the focusing lens 61, and are transmitted through the beam splitter 62 after being focused by the focusing lens 61. The imaging light is received and imaged by the detector 63 .

It can be understood that the imaging light reflected by the beam splitter 62 after being focused by the focusing lens 61 is received by the collimator 323 through the slow axis focusing lens 22 and the slow axis scanning galvanometer 21, and then enters the coupler 322 Interferential imaging occurs with the reference light. The interfering light enters the collimator 327 and is collimated into a parallel beam by the collimator 328. The light of each spectrum is separated by the grating 329. After being focused by the focusing lens 330, it is finally captured by the linear array Camera 331 receives.

The fundus multi-modal synchronous imaging system provided by the above-mentioned embodiments of the present invention combines line-scan rapid imaging technology with optical coherence tomography technology, adopts a common optical path resonant mirror synchronous scanning imaging method to effectively reduce system hardware, and adopts hollow narrow The slit mirror solves the bright spots reflected by the lens and cornea without affecting the scanning of optical coherence tomography, realizes the effective use of optical coherence tomography and line confocal scanning speed, and achieves the purpose of rapid surface imaging and tomographic imaging of the fundus retina.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (7)

1. A fundus multimodal synchronous imaging system fundus multimodal synchronous imaging system, comprising an optical coherence tomography module, a slow axis scanning module, an imaging module, a hollow slit mirror, and a line scanning confocal illumination module , a fast-axis scanning module and an objective lens, the optical coherence tomography module is used to form optical coherence tomography sample light, the slow-axis scanning module includes a slow-axis scanning galvanometer and a slow-axis focusing lens, the imaging module Including a focusing lens, a beam splitter and a detector, the line-scanning confocal illumination module includes a laser, a first collimator and a cylindrical mirror, and the fast-axis scanning module includes a fast-axis scanning galvanometer and a scanning lens; wherein: The optical coherence tomography sample light is collimated by a collimator and then enters the slow-axis scanning galvanometer, and then enters the beam splitter after passing through the slow-axis focusing lens, and the sample light reflected by the beam splitter passing through the slit of the hollow slit reflector after being focused by the focusing lens; The laser beam emitted by the laser enters the hollow slit reflector after passing through the first collimator and the cylindrical mirror in turn, and the laser beam is reflected by the hollow slit reflector and passes through the The optical coherence tomography sample light of the slit of the hollow slit mirror is combined to form combined light; The combined light passes through the fast-axis scanning galvanometer, the scanning lens and the objective lens to perform synchronous illumination and imaging of the fundus, and the formed imaging light passes through the objective lens, the scanning lens, and the eyepiece successively after being reflected by the retina of the fundus. The fast-axis scanning galvanometer and the slit of the hollow slit mirror enter the focusing lens, and after being focused by the focusing lens, the imaging light transmitted by the beam splitter is received and imaged by the detector The imaging light that is focused by the focusing lens and then reflected by the beam splitter passes through the slow-axis focusing lens and the slow-axis scanning galvanometer in order to form interference images in the optical coherence tomography module. 2. The fundus multi-modal synchronous imaging system according to claim 1, wherein the optical coherence tomography module is a swept source optical coherence tomography module or a spectral domain optical coherence tomography module. 3. The fundus multimodal synchronous imaging system according to claim 1, wherein the slow axis focusing lens in the slow axis scanning module and the focusing lens in the imaging module constitute a 4f system, and the slow axis scanning vibration The mirror and the fast-axis scanning galvanometer are respectively at the focal positions of the two lenses of the 4f system. 4. The fundus multi-modal synchronous imaging system according to claim 1, wherein the optical coherence tomography sample light is scanned by the slow-axis scanning galvanometer in the scanning of the hollow slit mirror. The trajectory is in the same direction as the slit. 5 . The fundus multi-modal synchronous imaging system according to claim 1 , wherein the spectroscope is a spectroscopic flat film, a spectroscopic prism, or a spectroscopic film. 6 . The fundus multi-modal synchronous imaging system according to claim 1 , wherein the hollow slit reflector is a glass sheet coated with a slit reflective film or a reflector cut with a slit. 7 . The fundus multi-modal synchronous imaging system according to claim 1 , wherein the non-converging direction of the cylindrical lenses is perpendicular to the slit direction of the hollow slit mirror.