Eye ground diopter and peripheral defocusing amount measuring device

Abstract

The utility model discloses a device for measuring fundus diopter and peripheral defocusing amount. Comprising a light source module used for providing a measurement light source, a light projection module used for projecting the measurement light source to the fundus of a detected eye and projecting a fundus image of the detected eye to an imaging detection module, and the imaging detection module used for detecting fundus image information of the detected eye. The light projection module comprises a galvanometer, a relay lens and an eyepiece which are sequentially arranged along a projection light path; the mirror surface of the galvanometer is conjugated with the pupil of the detected eye; the relay lens can move back and forth between the galvanometer and the eyepiece along the light path for diopter compensation. Diopter compensation is carried out by moving the relay lens, clear imaging of light spots can be realized, and the human diopter can be calculated subsequently according to the light spots; by arranging the galvanometer in the light path, the galvanometer performs X-Y optical scanning, so that the defocusing amount of the area outside the fundus macular area can be measured, and the defocusing amount of the whole retina area can be measured.

Description

Technical Field

[0001] The utility model relates to a field, in particular to a device for measuring fundus diopter and peripheral defocus amount. Background Art

[0002] At present, myopia prevention is mainly focused on healthy eye use, sufficient outdoor activities and reasonable nutritional diet. Myopia treatment measures mainly include low-concentration atropine, orthokeratology (OK lens), red light irradiation, wearing peripheral far-focus compensation lenses (including corneal contact lenses and frame glasses) and other methods. As early as the 1990s, animal experiments found that if the peripheral macular of the fundus is far from focus, it will promote the rapid development of myopia, and if the peripheral near-focus is close, it will effectively inhibit the development of myopia. At the 2022 International Forum on Innovation and Development of Visual Health, experts reported that a variety of corneal contact lenses and frame glasses with peripheral far-focus compensation have a significant inhibitory effect on the development of myopia. The refractive state of the peripheral retinal area has a greater impact on the occurrence and development of myopia. One of the main reasons is that there are fewer optic nerve fibers in the central retina. When the retina receives myopic signals from the central retina and hyperopic signals from the peripheral retina at the same time, this spatial signal superposition will make the hyperopic signals from the periphery dominate and allow the eye axis to continue to elongate. To achieve peripheral hyperopic defocus compensation, accurate measurement of peripheral defocus is required.

[0003] However, current conventional refractive detection equipment, such as ophthalmometers, vision screeners and other instruments that measure the refractive power of the macula cannot directly measure the peripheral defocus information of the eyeball; while measuring the peripheral defocus amount through an optical aberrometer has a complex structure, is inconvenient to operate, and takes a long time to measure. Utility Model Content

[0004] The utility model aims to provide a device for measuring fundus diopter and peripheral defocus, so as to solve the problem that the existing measuring device cannot accurately measure the peripheral defocus.

[0005] In order to solve the above technical problems, the present invention provides a fundus refractive power and peripheral defocus measuring device, comprising a light source module for providing a measuring light source, a light projection module for projecting the measuring light source onto the fundus of the eye to be measured and projecting the fundus image of the eye to be measured onto an imaging detection module, and an imaging detection module for detecting fundus image information of the eye to be measured; the light projection module comprises a galvanometer, a relay lens and an eyepiece arranged in sequence along a projection light path; the mirror surface of the galvanometer is conjugate with the pupil of the eye to be measured; the relay lens can move back and forth along the light path between the galvanometer and the eyepiece to perform refractive power compensation.

[0006] Furthermore, the light source module includes a first laser light source, a first collimator, a splitter consisting of a slit and a double wedge, and a second collimator, which are arranged in sequence; the first laser light source is collimated by the first collimator and then passes through a slit to form a slit light source, and the slit light source is then evenly irradiated to the splitter, and then the first laser light source is divided into two identical parallel light beams by the splitter and the second collimator and emitted as a splitting light source.

[0007] Furthermore, the light projection module also includes a first beam splitter, and the split light source emitted by the light source module is transmitted to the galvanometer through the first beam splitter, and then passes through the relay lens and the eyepiece in sequence, irradiates the pupil, and is projected to the fundus of the eye to be tested through the eye imaging system; the fundus splitting imaging image of the eye to be tested then passes through the eyepiece and the relay lens in sequence and returns to the galvanometer, and is finally reflected to the imaging detection module through the first beam splitter.

[0008] Furthermore, the imaging detection module includes a first image detector and a first imaging lens arranged on the incident light path of the first image detector. The fundus splitting imaging image of the eye being tested passes through the eye refractive system and then sequentially passes through the eyepiece, relay mirror, galvanometer and first imaging lens to be imaged onto the first image detector.

[0009] Furthermore, the light source module includes a third collimator and a second laser light source; the second laser light source is collimated by the third collimator and then sequentially passes through the galvanometer, relay lens and eyepiece to be projected onto the fundus of the eye to be tested; the imaging detection module also includes a second imaging lens and a second image detector for acquiring the fundus image of the eye to be tested, and the fundus image of the eye to be tested passes through the eye refractive system and then sequentially passes through the eyepiece, relay lens, galvanometer and second imaging lens to be imaged onto the second image detector.

[0010] Furthermore, the light projection module also includes a second beam splitter and a first dichroic mirror; the spot imaging light source emitted by the light source module is transmitted to the first dichroic mirror through the second beam splitter, and then reflected to the galvanometer through the first dichroic mirror; the spot imaging image of the fundus of the eye being tested is reflected to the second beam splitter through the first dichroic mirror after passing through the galvanometer, and then reflected to the second imaging lens through the second beam splitter.

[0011] The beneficial effects of the utility model are as follows: by moving the relay mirror back and forth to perform diopter compensation, clear imaging of the light spot can be achieved, so as to facilitate the subsequent calculation of the human diopter based on the light spot; by arranging a galvanometer in the optical path and making the galvanometer perform XY optical scanning, the defocus amount of areas other than the macular area of ​​the fundus can be measured, thereby realizing the measurement of the defocus amount of the entire retinal area. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The same reference numerals are used in these drawings to represent the same or similar parts. The exemplary embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0013] Figure 1 A schematic diagram of light path distribution according to an embodiment of the present invention;

[0014] Figure 2 This is a schematic diagram of the splitting and spot imaging measurement principle of an embodiment of the present invention;

[0015] Figure 3(a) is the optical path diagram under the condition of hyperopia + relay lens compensation;

[0016] Figure 3(b) is the optical path diagram under the condition of myopia + relay lens compensation;

[0017] Figure 3(c) is a diagram of the myopic defocus optical path when the relay lens is not compensated;

[0018] Among them, 101, the first optical fiber; 102, the first collimator; 103, the splitter; 104, the second collimator; 105, the first beam splitter; 106, the first imaging lens; 107, the first image detector; 201, the second optical fiber; 202, the third collimator; 203, the second beam splitter; 204, the first dichroic mirror; 205, the second imaging lens; 206, the second image detector; 301, the galvanometer; 302, the relay lens; 303, the eyepiece. DETAILED DESCRIPTION

[0019] like Figure 1 The fundus refractive power and peripheral defocus measuring device shown in the figure comprises a light source module for providing a measuring light source, a light projection module for projecting the measuring light source onto the fundus of the eye to be measured and projecting the fundus image of the eye to be measured onto the imaging detection module, and an imaging detection module for detecting fundus image information of the eye to be measured; the light projection module comprises a galvanometer 301, a relay lens 302 and an eyepiece 303 arranged in sequence along the projection light path; the mirror surface of the galvanometer 301 is conjugate with the pupil to ensure that the light spot can be completely irradiated into the fundus through the pupil; the relay lens 302 can move back and forth along the light path between the galvanometer 301 and the eyepiece 303 to perform diopter compensation.

[0020] The utility model can realize clear imaging of the light spot by moving the relay mirror forward and backward to perform diopter compensation, so as to facilitate the subsequent calculation of the human diopter based on the light spot; by arranging a galvanometer in the optical path and making the galvanometer perform XY optical scanning, the defocus amount of the area outside the macular area of ​​the fundus can be measured, thereby realizing the measurement of the defocus amount of the entire retinal area.

[0021] According to an embodiment of the present application, the light source module includes a first laser light source, a first collimator 102, a splitter 103, and a second collimator 104 arranged in sequence; the first laser light source is collimated by the first collimator 102 and then passes through a slit to form a slit light source, and the slit light source is then evenly irradiated to the splitter 103, and then the first laser light source is split into two identical parallel lights by the splitter 103 and the second collimator 104 and emitted as a splitting light source. The splitting light source emitted by the light source module passes through the galvanometer 301 and forms a primary image of the slit on the focal plane of the relay lens 302; the image of the slit is irradiated to the fundus through the eyepiece 303. When the eye refractive system does not have hyperopia or myopia, the slit is secondary imaged to the fundus to form a bright slit image, but if the eye has refractive errors, the slit forms two separate light spots on the fundus.

[0022] According to an embodiment of the present application, the light projection module further includes a first beam splitter 105, and the split light source emitted by the light source module is transmitted to the galvanometer 301 through the first beam splitter, and then sequentially passes through the relay lens 302 and the eyepiece 303, irradiates the pupil, and is projected to the fundus of the eye under test through the eye imaging system; the fundus splitting imaging image of the eye under test then sequentially passes through the eyepiece 303 and the relay lens 302 to return to the galvanometer 301, and finally is reflected to the imaging detection module through the first beam splitter 105. The first beam splitter 105 can facilitate the coupling of the split light source and the detection light path.

[0023] According to an embodiment of the present application, the imaging detection module includes a first image detector 107 and a first imaging lens 106 arranged on the incident light path of the first image detector 107. The fundus splitting imaging image of the eye under test passes through the eye refractive system, and then passes through the eyepiece 303, the relay lens 302, the galvanometer 301 and the first imaging lens 106 in sequence to be imaged on the first image detector 107. Due to the refractive error of the eye, the image detected on the image detector is not a perfect image, which affects the determination of the boundary and center position of the spot image by the image processing, resulting in a limited measurement range of the splitting imaging; while in the present device, the relay lens 302 and the eyepiece 303 are confocal, and the relay lens 302 can move forward and backward to achieve diopter compensation.

[0024] According to one embodiment of the present application, the light source module includes a third collimator 202 and a second laser light source; after the second laser light source is collimated by the third collimator, it passes through the galvanometer 301, the relay lens 302 and the eyepiece 303 in sequence and is projected onto the fundus of the eye to be tested; the imaging detection module also includes a second imaging lens 205 and a second image detector 206 for acquiring the fundus image of the eye to be tested, and the fundus image of the eye to be tested passes through the eye refractive system and then passes through the eyepiece 303, the relay lens 302, the galvanometer 301 and the second imaging lens 205 in sequence and is imaged onto the second image detector 206.

[0025] According to one embodiment of the present application, the light projection module also includes a second beam splitter 203 and a first dichroic mirror 204; the spot imaging light source emitted by the light source module is transmitted to the first dichroic mirror 204 through the second beam splitter 203, and then reflected to the galvanometer 301 through the first dichroic mirror 204; the spot imaging image of the fundus of the eye being tested is reflected to the second beam splitter 203 through the first dichroic mirror 204 after passing through the galvanometer 301, and then reflected to the second imaging lens 205 through the second beam splitter 203.

[0026] like Figure 1 As shown, the second laser light source from the second optical fiber 201 is collimated by the third collimator and coupled into the split imaging optical path by the first dichroic mirror 204. The optical path returned from the fundus is separated by the first dichroic mirror 204, and is imaged to the second imaging lens 205 after being reflected by the second beam splitter 203. The circular light spot is not so sensitive to the boundary mode caused by the refractive error of the human eye. Combined with the refractive compensation of the relay lens 302, the refractive power within the range of ±15D can be measured. The spot ellipticity analysis of the circular light spot can realize the astigmatism of the eye refractive system, that is, the cylindrical power.

[0027] According to one embodiment of the present application, Figure 2 As shown, the pattern of the split or light spot in the case of myopia that hits the fundus is used as the object of the entire imaging device, and the object is imaged to the far point through the eye imaging system, and the reciprocal of the distance from this position point to the eye (in meters) is the diopter. The image of the far point is imaged by the eyepiece 303 as the object of the eyepiece 303 to a certain position in front of the relay lens 302, and the distance from this position to the focus of the relay lens 302 is the refractive compensation movement distance of the relay lens 302. The relay lens 302 and the imaging lens will image the image formed by the eyepiece 303 onto the image detector again. However, at this time, the image detector is not in the ideal image plane position, so it is a relatively blurred image spot. Through image processing, the center separation distance of the two separated image spots obtained by the first image detector 107 (or the spot size obtained by the second image detector 206) can be obtained. Then, the refractive compensation distance of the relay lens 302 and the refractive power of the human eye can be calculated based on the center separation distance of the two separated image spots obtained by the first image detector 107 (or the spot size obtained by the second image detector 206).

[0028] When the first laser light source is used for measurement, the first image detector 107 obtains two separated image spots. This measurement method is called split imaging measurement. The principle is as follows: Figure 2 As shown, at this time, the diopter compensation distance of the first relay lens 302 is:

[0029]

[0030] The refractive power of the human eye is:

[0031]

[0032] Among them, a, b, and c are

[0033] a=f2f3+f3f4-f2f4-f2d3-f3d2+f4d2+f3d3+d2d3

[0034]

[0035] c=b+a*(d1-f2')

[0036] f2, f3, f4 are respectively the object side focal lengths of the eyepiece 303, the relay lens 302 and the imaging lens; f2', f3', f4' are respectively the image side focal lengths of the eyepiece 303, the relay lens 302 and the imaging lens; d1, d2, d3 are respectively the distances from the image side principal point of the human eye to the object side principal point of the eyepiece 303, the distance from the image side principal point of the eyepiece 303 to the object side principal point of the relay lens 302 and the distance from the image side principal point of the relay lens 302 to the object side principal point of the imaging lens.

[0037] When the second laser light source is used for measurement, the second image detector 206 obtains a circular light spot. This measurement method is light spot imaging measurement. The principle is shown in Figures 3(a), 3(b) and 3(c), where Figure 3(a) is an optical path diagram under hyperopia + relay lens compensation, 3(b) is an optical path diagram under myopia + relay lens compensation, and 3(c) is a myopia defocus optical path diagram when the relay lens is not compensated.

[0038] At this time, the diopter compensation distance d of the relay lens lx for:

[0039]

[0040] When the relay lens is far away from the eyepiece, it is positive, otherwise it is negative.

[0041] a=sd[f2′(f3′-d3)] 2 -π(h1f4'f3) 2

[0042]

[0043]

[0044] The diopter D of the human eye is:

[0045]

[0046] The value units of each symbol in the formula are mm; s d is the image area size collected by the second image detector; lr For a longer distance.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. A device for measuring fundus refractive power and peripheral defocus, characterized in that: It comprises a light source module for providing a measuring light source, a light projection module for projecting the measuring light source onto the fundus of the eye to be measured and projecting the fundus image of the eye to be measured onto an imaging detection module, and an imaging detection module for detecting fundus image information of the eye to be measured; the light projection module comprises a galvanometer, a relay lens and an eyepiece lens sequentially arranged along a projection light path; the mirror surface of the galvanometer is conjugate with the pupil of the eye to be measured; the relay lens can move back and forth along the light path between the galvanometer and the eyepiece lens to perform diopter compensation.

2. The fundus refractive power and peripheral defocus measurement device according to claim 1, characterized in that: The light source module comprises a first laser light source, a first collimator, a splitter consisting of a slit and a double wedge, and a second collimator, which are arranged in sequence; the first laser light source is collimated by the first collimator and then passes through a slit to form a slit light source, the slit light source is then evenly irradiated to the splitter, and then the first laser light source is divided into two identical parallel lights by the splitter and the second collimator to be emitted as a splitting light source.

3. The fundus refractive power and peripheral defocus measurement device according to claim 2, characterized in that: The light projection module also includes a first beam splitter. The split light source emitted by the light source module is transmitted to the galvanometer through the first beam splitter, and then passes through the relay lens and the eyepiece in sequence to illuminate the pupil, and then is projected to the fundus of the eye to be tested through the eye imaging system; the fundus splitting imaging image of the eye to be tested then passes through the eyepiece and the relay lens in sequence and returns to the galvanometer, and finally is reflected to the imaging detection module through the first beam splitter.

4. The fundus refractive power and peripheral defocus measurement device according to claim 3, characterized in that: The imaging detection module includes a first image detector and a first imaging lens arranged on the incident light path of the first image detector. The fundus splitting imaging image of the eye being tested passes through the eye refractive system and then sequentially passes through the eyepiece, relay mirror, galvanometer and first imaging lens to be imaged onto the first image detector.

5. The fundus refractive power and peripheral defocus measurement device according to claim 1, characterized in that: The light source module includes a third collimator and a second laser light source; the second laser light source is collimated by the third collimator and then sequentially passes through the galvanometer, relay lens and eyepiece to be projected onto the fundus of the eye to be tested; the imaging detection module also includes a second imaging lens and a second image detector for acquiring the fundus image of the eye to be tested, and the fundus image of the eye to be tested passes through the eye refractive system and then sequentially passes through the eyepiece, relay lens, galvanometer and second imaging lens to be imaged onto the second image detector.

6. The fundus refractive power and peripheral defocus measurement device according to claim 5, characterized in that: The light projection module also includes a second beam splitter and a first dichroic mirror; the spot imaging light source emitted by the light source module is transmitted to the first dichroic mirror through the second beam splitter, and then reflected to the galvanometer through the first dichroic mirror; the spot imaging image of the fundus of the eye being tested is reflected to the second beam splitter through the first dichroic mirror after passing through the galvanometer, and then reflected to the second imaging lens through the second beam splitter.

Images