Disclosure of Invention
In view of this, it is necessary to provide a true color wide-beam fundus scanning imaging system and imaging method for the defect that there is a relatively large distortion in image color in fundus scanning imaging of the prior art.
In order to solve the problems, the application adopts the following technical scheme:
The application provides a true color wide beam fundus scanning imaging system, which comprises an illumination light path, an imaging detection light path and a control system, wherein:
The illumination light path comprises an LED light source module, an illumination lens, a one-dimensional scanning galvanometer, a scanning lens, a reflector and an eye objective lens, wherein the LED light source module comprises a first LED light source unit, a second LED light source unit and a third LED light source unit, the first LED light source unit comprises a first LED light source, a first collecting lens, a first slit diaphragm and a first dichroic mirror, the second LED light source unit comprises a second LED light source, a second condenser, a second dichroic mirror and a second slit diaphragm, the third LED light source unit comprises a third LED light source and a third condenser, and the imaging detection light path comprises the eye objective lens, the reflector, the scanning lens, the one-dimensional scanning galvanometer, a detection spectroscope, a first imaging objective lens, a detection slit, a second imaging objective lens and a camera;
The control system comprises a control device and a driving unit, wherein the control device can control the driving unit to drive the one-dimensional scanning galvanometer to rotate and swing; the control device can respectively control the switch of the first LED light source, the second LED light source and the third LED light source, and can control the exposure of a selected area on the photosensitive surface of the camera;
The light beam emitted by the first LED light source irradiates the first slit diaphragm after passing through the first condenser, the linear light beam emitted by the first slit diaphragm is incident on the first dichroic mirror and reflected by the first dichroic mirror, the light beam emitted by the second LED light source irradiates the second slit diaphragm after being reflected by the second dichroic mirror after passing through the second condenser, the light beam emitted by the third LED light source irradiates the second slit diaphragm after being transmitted by the second dichroic mirror after passing through the third condenser, and the light beams of the second LED light source and the third LED light source emitted by the second slit diaphragm are incident on the first dichroic mirror and transmitted by the first dichroic mirror;
The light beams of the first LED light source, the second LED light source and the third LED light source which are emitted from the first dichroic mirror pass through the illumination lens, wherein part of the light beams are blocked by the detection spectroscope, part of the light beams which are not blocked pass through the one-dimensional scanning galvanometer and the scanning lens in sequence and enter the reflector, the reflector reflects part of the light beams into the eye objective, the eye objective transmits the light beams to the pupil of the human eye, a wide linear illumination area is formed on the fundus after passing through the eye diopter system, the wide linear illumination area forms an intermediate imaging surface of retina after passing through the human eye and the eye objective, the intermediate imaging surface passes through the reflector and enters the scanning lens, the scanning lens and then enters the one-dimensional scanning galvanometer, the one-dimensional scanning galvanometer reflects part of the light beams into the detection spectroscope, the detection spectroscope focuses part of the imaging light beams on the detection slit, and focuses on the photosensitive surface of the camera after passing through the detection slit.
The second object of the present application is to provide an imaging method of the true color wide beam fundus scanning imaging system, comprising the following steps:
The light beam emitted by the first LED light source irradiates the first slit diaphragm after passing through the first condenser, the linear light beam emitted by the first slit diaphragm is incident on the first dichroic mirror and reflected by the first dichroic mirror, the light beam emitted by the second LED light source irradiates the second slit diaphragm after being reflected by the second dichroic mirror after passing through the second condenser, the light beam emitted by the third LED light source irradiates the second slit diaphragm after being transmitted by the second dichroic mirror after passing through the third condenser, and the light beams of the second LED light source and the third LED light source emitted by the second slit diaphragm are incident on the first dichroic mirror and transmitted by the first dichroic mirror;
The light beams of the first LED light source, the second LED light source and the third LED light source which are emitted from the first dichroic mirror pass through the illumination lens, wherein part of the light beams are blocked by the detection spectroscope, part of the light beams which are not blocked pass through the one-dimensional scanning galvanometer and the scanning lens in sequence and enter the reflector, the reflector reflects part of the light beams into the eye objective, the eye objective transmits the light beams to the pupil of the human eye, a wide linear illumination area is formed on the fundus after passing through the eye diopter system, the wide linear illumination area forms an intermediate imaging surface of retina after passing through the human eye and the eye objective, the intermediate imaging surface passes through the reflector and enters the scanning lens, the scanning lens and then enters the one-dimensional scanning galvanometer, the one-dimensional scanning galvanometer reflects part of the light beams into the detection spectroscope, the detection spectroscope focuses part of the imaging light beams on the detection slit, and focuses on the photosensitive surface of the camera after passing through the detection slit.
By adopting the technical scheme, the application has the following beneficial effects:
The application provides a true color wide-beam fundus scanning imaging system and an imaging method, which adopt wide linear light beams to illuminate fundus, realize illumination and image data acquisition of a banded region of fundus at one time, wherein the banded fundus region comprises a plurality of rows of pixels on a camera, which is different from the traditional line scanning confocal fundus imaging that only acquires pixel information of one or a few rows of fundus at one time, can increase exposure time of fundus images on the camera, and improve imaging signal-to-noise ratio.
In addition, the application adopts the three-color LED light sources to respectively illuminate the fundus, adopts the black-and-white camera to respectively record the image information of the fundus under the illumination of the corresponding color LEDs, has the spectrum wider than that of laser, and can obtain the true color image of the fundus by carrying out image fusion on the monochromatic fundus image obtained by the three-color LED light sources. Compared with a color camera, the black-and-white camera has larger effective photosensitive size of pixels and can improve the signal-to-noise ratio of fundus imaging.
In addition, the application is provided with a detection spectroscope on the light path system, and the detection spectroscope effectively utilizes a part of the illumination light beam and the detection light beam, and can effectively inhibit stray light caused by the scanning lens, the eye objective lens and the cornea of the human eye.
Detailed Description
Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present application and should not be construed as limiting the application.
In the description of the present application, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "horizontal", "inner", "outer", etc., are based on the directions or positional relationships shown in the drawings, are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.
The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent.
Referring to fig. 1, the true color wide line beam fundus scanning imaging system provided by the embodiment of the application comprises an illumination light path 10, an imaging detection light path 20 and a control system 30. Specific implementations of the various components are described in detail below.
The illumination light path 10 comprises an LED light source module 11, an illumination lens 12, a one-dimensional scanning galvanometer 13, a scanning lens 14, a reflector 15 and an objective lens 16. The LED light source module 11 includes a first LED light source unit 110, a second LED light source unit 120, and a third LED light source unit 130. The first LED light source unit 110 includes a first LED light source 111, a first condenser 112, a first slit diaphragm 113, and a first dichroic mirror 114. The second LED light source unit 120 includes a second LED light source 121, a second condenser lens 122, a second dichroic mirror 123, and a second slit diaphragm 124. The third LED light source unit 130 includes a third LED light source 131 and a third condenser 132.
Further, the first LED light source 111, the second LED light source 121 and the third LED light source 131 are light sources of different colors.
Further, the first LED light source 111 is blue, the second LED light source 121 is green, and the third LED light source 131 is red.
It can be understood that the spectrum width of the LED light source is wider than that of the laser, and a true color image of a sample can be obtained when the line light beam generated by combining the red, green and blue LED light sources is used for line scanning imaging, and a true color sample image can be obtained when the generated line light beam is used for line scanning imaging.
The imaging detection light path 20 includes the objective lens 16, the reflector 15, the scanning lens 14, the one-dimensional scanning galvanometer 13, a detection spectroscope 21, a first imaging objective lens 22, a detection slit 23, a second imaging objective lens 24, and a camera 25.
Further, the camera 25 is a black-and-white camera. The camera 25 is a TDI camera or an area array camera.
The control system 30 comprises a control device 31 and a driving unit 32, wherein the control device 31 can control the driving unit 32 to drive the one-dimensional scanning galvanometer 13 to rotate and swing, the control device 31 can respectively control the switch of the first LED light source 111, the switch of the second LED light source 121 and the switch of the third LED light source 131, and the control device 31 can control the exposure of a selected area on the photosensitive surface of the camera 25.
Further, under the control of the control device 31, the first LED light source 111, the second LED light source 121 and the third LED light source 131 emit light sequentially and respectively, the exposure trigger of the camera 25 is synchronous with the light emission time sequence of the first LED light source 111, the second LED light source 121 and the third LED light source 131 under the control of the control device 31, and the control device 31 synchronously controls the swing of the one-dimensional scanning galvanometer 13.
The true color wide wire harness fundus scanning imaging system provided by the embodiment of the application has the following working modes:
The light beam emitted by the first LED light source 111 passes through the first condenser 112 and irradiates the first slit diaphragm 113, the linear light beam emitted from the first slit diaphragm 113 is incident on the first dichroic mirror 114 and reflected by the first dichroic mirror 114, the light beam emitted by the second LED light source 121 passes through the second condenser 122 and irradiates the second slit diaphragm 124 after being reflected by the second dichroic mirror 122, the light beam emitted by the third LED light source 131 passes through the third condenser 132 and irradiates the second slit diaphragm 124 after being transmitted by the second dichroic mirror 123, and the light beams of the second LED light source 121 and the third LED light source 131 emitted from the second slit diaphragm 124 are incident on the first dichroic mirror 114 and transmitted by the first dichroic mirror 114.
After passing through the illumination lens 12, the light beams of the first LED light source 111, the second LED light source 121 and the third LED light source 131 emitted from the first dichroic mirror 114 are blocked by the detection beam splitter 21, the light beams of the non-blocked light beams enter the reflector 15 through the one-dimensional scanning beam splitter 13 and the scanning lens 14 in sequence, the light beams are reflected by the reflector 15 into the eye objective 16, the eye objective 16 transmits the light beams to the pupil of the human eye, a wide linear illumination area is formed on the fundus after passing through the eye refractive system, the wide linear illumination area forms an intermediate imaging surface of retina after passing through the eye and the eye objective 16, the intermediate imaging surface enters the scanning lens 14 after passing through the scanning lens 14, the light beams are reflected by the one-dimensional scanning beam splitter 13 into the detection beam splitter 21, the light beams are reflected by the detection beam splitter 21 into the first imaging lens 22, the first imaging lens 22 focuses on the detection slit 22, and the imaging slit 24 is formed on the imaging surface after passing through the imaging slit 24.
It will be appreciated that since a portion of the illumination beam is located in the optical path, a portion of the illumination beam is blocked by the beam splitter 21, another portion can be directly transmitted, a portion of the illumination beam is reflected by the beam splitter 21 into the subsequent imaging optical path to participate in imaging, another portion is directly transmitted forward without being blocked by the beam splitter 21 to participate in imaging, and the beam splitter 21 serves the purpose of eliminating stray light caused by reflection or scattering of the scan lens 14, the objective lens 16, and the cornea of the human eye.
Further, the human eye retina position R, the image plane position P of the objective lens 16, the slit position S1 of the first slit diaphragm 113, the slit position S2 of the second slit diaphragm 124, and the photosurface position I of the camera 25 are located at optically conjugate positions.
Further, the first slit diaphragm 113 and the second slit diaphragm 124 are arranged as wide-line slits, and the detecting slit 23 is also arranged as wide-line slits, so that the camera 25 adopts a TDI camera or an area array camera, and at this time, wide-line beam line scanning imaging can be performed, thereby improving the imaging speed and the signal-to-noise ratio.
It can be understood that after the linear light beams emitted from the first slit diaphragm 113 and the second slit diaphragm 124 pass through the illumination lens 12, the one-dimensional scanning galvanometer 13, the reflective mirror 15, the objective lens 16 and the refractive system of human eyes, a wide beam illumination area is formed in the retinal area of the fundus, and along with the swing of the one-dimensional scanning galvanometer 13, the wide beam illumination area of the fundus also moves together, that is, different areas of the retina are sequentially illuminated by the strip-shaped light beams, the light beams reflected from the fundus enter the one-dimensional scanning galvanometer 13 after passing through the objective lens 16, the reflective mirror 15 and the scanning lens 14, then enter the subsequent first imaging objective lens 22, the detection slit 23 and the second imaging objective lens 24, and imaging is performed on the camera 25, that is, imaging is realized in a scanning-releasing mode.
Referring to fig. 2, a schematic diagram of LED light source lighting and camera exposure triggering timing provided in some preferred embodiments is shown in the following control flow:
The control device 31 controls the one-dimensional scanning galvanometer 13 to swing a position and controls the first LED light source 111 to be turned on, and the control device 13 controls the camera 25 to record an image of a wide wire harness illumination area on the retina under the irradiation of the first LED light source 111; the control device 31 controls the first LED light source 111 to be turned off and synchronously turns on the second LED light source 121, the control device 31 controls the camera 25 to record images of a wide harness illumination area on the retina under the condition that the second LED light source 121 irradiates, the control device 31 controls the second LED light source 121 to be turned off and the third LED light source 131 to be turned on, the control device 31 controls the camera 25 to record images of a wide harness illumination area on the retina under the condition that the third LED light source 131 irradiates, the control device 31 controls the one-dimensional scanning galvanometer 13 to swing to the next position, and repeatedly controls the first LED light source 111, the second LED light source 121, the third LED light source 131 to be turned on and the exposure and the image reading of the camera 25, all the wide harness images acquired under the condition that the first LED light source 111 is turned on are spliced to obtain first wide fundus image corresponding to the single-color wide fundus image under the first LED light source 111, all the wide fundus image acquired under the condition that the second LED light source 121 is turned on is recorded to be recorded to the first single-color fundus image wide fundus image corresponding to the single-color wide fundus image, the control device 31 controls the one-dimensional scanning galvanometer 13 to swing to the one-dimensional scanning galvanometer 13 to the next position, and repeatedly controls the first LED light source 121 and the exposure and the image reading of the first fundus image under the first single-color fundus image wide image corresponding to the first image light source 131 to be spliced to obtain the first single-color wide fundus image corresponding to the first single-color wide fundus image, obtaining the true color image of the fundus oculi.
It can be understood that in this embodiment, three-color LED light sources are used to illuminate the fundus respectively, black and white cameras are used to record the image information of the fundus under the illumination of the LEDs with corresponding colors respectively, the spectrum of the LED light sources is wider than that of the laser, and image fusion is performed on the monochromatic fundus images obtained by the three-color LED light sources, so that a true color image of the fundus can be obtained. Compared with a color camera, the black-and-white camera has larger effective photosensitive size of pixels and can improve the signal-to-noise ratio of fundus imaging.
According to the true color wide-beam fundus scanning imaging system and the imaging method provided by the embodiment of the application, the fundus is illuminated by the wide linear light beam, illumination and image data acquisition are carried out on a banded area of the fundus at one time, and the banded fundus area comprises a plurality of rows of pixels on a camera, so that the exposure time of a fundus image on the camera can be increased and the imaging signal-to-noise ratio can be improved, unlike the traditional line scanning confocal fundus imaging in which only one or a few rows of pixel information of the fundus is acquired at one time.
It will be understood that the technical features of the above-described embodiments may be combined in any manner, and that all possible combinations of the technical features in the above-described embodiments are not described for brevity, however, they should be considered as being within the scope of the description provided in the present specification, as long as there is no contradiction between the combinations of the technical features.
The foregoing description of the preferred embodiments of the present application has been provided for the purpose of illustrating the general principles of the present application and is not to be construed as limiting the scope of the application in any way. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application, and other embodiments of the present application as will occur to those skilled in the art without the exercise of inventive faculty, are intended to be included within the scope of the present application.