Corneal curvature and eye parameter measurement integrated system

Abstract

The utility model relates to the technical field of optical presentation, in particular to a corneal curvature and eye parameter measurement integrated system. Comprising an OCT imaging module and a measuring module, the OCT imaging module adopts a super-radiation light emitting diode to emit near-infrared light beams, the near-infrared light beams pass through a circulator and then enter an optical fiber coupler, one path of split light serves as a reference arm, and the other path of split light serves as a sample arm; the reference arm passes through the collimator, the reflecting prism and the high-speed motion voice coil motor, is reflected back to the original path by the plane mirror, and enters the detector after passing through the optical fiber coupler; the sample arm enters the eyeball sample through the collimator, reaches a set optical path and then returns to the detector along the same path; the measuring module comprises a microarray reflector, a zoom lens group, a reflecting prism and a CCD camera. A light source enters an eyeball after passing through the microarray reflector, the prism focus lens and the zoom lens group, and enters the CCD camera after passing through the fundus retina. According to the method, comprehensive corneal morphology information can be provided, so that a high-precision measurement result is obtained.

Description

Technical Field

[0001] The utility model relates to the technical field of optical presentation, and particularly relates to an integrated system for measuring corneal curvature and eye parameters. Background Art

[0002] Optometers and ophthalmic multi-parameter measuring instruments are indispensable devices in ophthalmic examinations and diagnoses, and are used to evaluate multiple parameters such as the diopter, corneal curvature, and anterior segment structure of the anterior segment of the eye. These parameters are crucial for accurately diagnosing eye diseases such as myopia, hyperopia, astigmatism, cataract, and glaucoma.

[0003] At present, the detection light source optical path system of an optometer includes a light source, a circulator, and a coupler. The light emitted by the light source enters the circulator, and a part of the light coming out of the circulator enters a 2x2 fiber optic coupler and is split according to a 50:50 ratio. The emitted light enters the sample arm optical path and the reference arm optical path respectively. A collimator and a semi-transparent semi-reflective flat mirror are connected in the sample arm. The light passes through the collimator to output a collimated beam, and then enters the semi-transparent semi-reflective flat mirror. The transmitted light enters the eyeball, and after being reflected by the eyeball, it returns along the original optical path through the semi-transparent semi-reflective flat mirror and enters the coupler. The reference arm optical path system includes a second collimator, an optical delay line, a cylindrical lens, and a mirror arranged in sequence along the light incident direction. The light coming out of the fiber optic coupler becomes parallel light after passing through the second collimator and enters the optical delay line. The light emitted after passing through the optical delay line is focused on the mirror by the cylindrical lens and returns to the fiber optic coupler along the original path. The photoelectric detection and acquisition system includes a photoelectric balanced detector, a data acquisition card, and a processor. The light returning from the sample arm optical path system and the light returning from the reference arm optical path system interfere in the fiber optic coupler and are received by the photoelectric balanced detector. Another part of the light coming out of the circulator enters the photoelectric balanced detector. The above optical signals are converted into electrical signals, collected by the data acquisition card, and transmitted to the processor for signal analysis and processing. The imaging system includes a first focusing lens, a second focusing lens, a microlens array, and a CCD camera. When the light reflected from the eyeball returns to the semi-transparent semi-reflective flat mirror, half of the light enters the focusing lens group. When passing through the focusing lens, parallel light is emitted, converges through the microlens array, and is received by the imaging device. The data received by the imaging device is transmitted to the processor for data processing. The above system can only measure the curvature of the central area of the cornea and cannot provide comprehensive corneal morphology information. Summary of the Utility Model

[0004] To solve the problems existing in the prior art, the present utility model provides an integrated system for measuring corneal curvature and eye parameters. The system includes: an OCT imaging module and a measurement module. The OCT imaging module uses a superluminescent diode to emit a near-infrared beam, which enters an optical fiber coupler with a splitting ratio of 50:50 after passing through a circulator. One path of the split light serves as a reference arm, and the other path serves as a sample arm. The reference arm passes through a collimator, a reflecting prism, and a high-speed moving voice coil motor, and then is reflected back along the original path by a plane mirror, and reaches a detector after passing through the optical fiber coupler. The sample arm enters the eye sample through a collimator, and returns to the detector along the original path after reaching a set optical path. The measurement module includes a microarray mirror, a zoom lens group, a reflecting prism, and a CCD camera. The light source is incident on the eye after passing through the microarray mirror, a prism focusing lens, and the zoom lens group, and is reflected into the CCD camera after passing through the fundus retina. This application can provide comprehensive corneal morphology information, thereby obtaining high-precision measurement results.

[0005] The present utility model adopts the following technical solution: an integrated system for measuring corneal curvature and eye parameters, including an OCT imaging module and a measurement module. The OCT imaging module uses a superluminescent diode to emit a near-infrared beam, which enters an optical fiber coupler with a splitting ratio of 50:50 after passing through a circulator. One path of the split light serves as a reference arm, and the other path serves as a sample arm. The reference arm passes through a collimator, a reflecting prism, and a high-speed moving voice coil motor, and then is reflected back along the original path by a plane mirror, and reaches a detector after passing through the optical fiber coupler. The sample arm enters the eye sample through a collimator, and returns to the detector along the original path after reaching a set optical path. The measurement module includes: a microarray mirror, a zoom lens group, a reflecting prism, and a CCD camera. The light source is incident on the eye after passing through the microarray mirror, a prism focusing lens, and the zoom lens group, and is reflected into the CCD camera after passing through the fundus retina.

[0006] Further, the microarray mirror forms a set pattern on the microarray mirror by controlling the flipping of some of the mirrors.

[0007] Further, a focusing lens is provided behind the zoom lens group for measuring corneal curvature.

[0008] Further, a data acquisition card and a computer device are also connected behind the detector.

[0009] The beneficial effects of the present utility model are as follows: The optical path structure proposed in the present utility model can simultaneously measure corneal curvature (corneal topography), refractive power, and the distances between various tissue components in the eye. At the same time, the light beam is mapped into structured light by the microarray mirror, and a high-precision external contour can be obtained during measurement, with an accuracy reaching the order of a few micrometers. Description of the Drawings

[0010] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0011] Figure 1 Schematic structural diagram of an integrated system for measuring corneal curvature and eye parameters according to an embodiment of the present invention;

[0012] Figure 2 Schematic structural diagram of a CCD imaging according to an embodiment of the present invention;

[0013] Figure 1 In the figure, 1. SLD light source; 2. Circulator; 3. Coupler; 4. Collimator of the measurement module; 5. Collimator of the OCT system module; 6. Reflective prism of the OCT system module; 7. Reflector; 8. Balanced detector; 9. Acquisition card; 10. Computer; 11. CCD camera; 12. Reflective prism of the measurement module; 13. Microarray reflector DMD; 14. Light source; 15. Retroreflector; 16. Voice coil motor; 17. Zoom lens group; 18. Eyeball. Detailed implementation manners

[0014] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0015] Schematic structural diagram of an integrated system for measuring corneal curvature and eye parameters according to an embodiment of the present invention is as Figure 1As shown, it includes an OCT imaging module and a measurement module. In the OCT system module, a near-infrared beam is emitted by a superluminescent diode (SLD) light source, and then enters a circulator, and then enters an optical fiber coupler with a splitting ratio of 50:50. One of the split beams serves as the reference arm, and the other serves as the sample arm. In the reference arm, the beam is collimated by a collimator, then passes through a reflection prism and a high-speed moving voice coil motor with a retroreflector (this voice coil motor is based on the laws of electromagnetic induction and the principle of Lorentz force. When energized, the motor moves in a certain direction. When the current direction is changed, the motor moves in the opposite direction. The motor drives the retroreflector to move back and forth, and by changing the optical path, it is possible to measure and image different depths of the sample), and is reflected back to the reflection prism and then enters a plane mirror, and then returns along the original path. The beam returns along the original path, passes through the collimator again, and then enters the optical fiber coupler, and after passing through the optical fiber coupler, it enters the detector. In the sample arm, the beam is collimated by a collimator and then enters the eye sample, is reflected after reaching the corresponding optical path position through the eye, returns along the original path, enters the collimator again, and then enters the detector through the coupler.

[0016] In the measurement module, the light source emits uniform illumination onto a digital micromirror device (DMD). By controlling the flipping of the mirror array on the DMD, a specific-shaped pattern light spot can be obtained. Further, the light spot passes through a prism focusing lens and a zoom lens group. After passing through the zoom lens group, if you want to measure the refractive power of the eye, no other optical elements need to be added. The parallel light is directly incident on the eye, and after being reflected by the fundus retina, it enters the acquisition optical path on the other side as shown in the figure, passes through the zoom lens group, reflection prism, focusing lens, and reflection prism, and finally enters the CCD for refractive power measurement. If you want to measure the corneal curvature, a focusing lens (not shown in the figure) needs to be added to focus the light on the cornea, and by measuring the topography of the cornea, the corneal curvature value can be obtained.

[0017] As Figure 2 shown, the phase at point D displayed on the CCD is equal to the phase at point A because their imaging positions on the CCD coincide, that is, φ D =φ A , so there is φ CD =φ CA =φ A -φ C ; Using the principle of similar triangles, it can be known that ΔPID~ΔACD, so there is Since d is much larger than The formula can be simplified to where p is the fringe spacing and d is the distance between the incident optical axes of the two elements, and thus the refractive power value can be calculated.

[0018] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. An integrated system for measuring corneal curvature and eye parameters, comprising: The OCT imaging module and the measuring module are characterized in that: the OCT imaging module uses a superluminescent diode to emit a near-infrared light beam, which enters a fiber coupler with a splitting ratio of 50:50 after passing through a circulator, and one path of the split light is used as a reference arm, and the other path of the split light is used as a sample arm; the reference arm passes through a collimator, a reflecting prism and a high-speed motion voice coil motor, and is reflected back to the original path by a plane reflecting mirror, and enters a detector after passing through a fiber coupler; the sample arm enters an eyeball sample through a collimator, and returns to the detector along the original path after reaching a set optical path; the measuring module comprises: a microarray reflector, a zoom lens group, a reflecting prism and a CCD camera; the light source passes through the microarray reflector, the prism focusing lens and the zoom lens group, and is incident on the eyeball, and is reflected by the fundus retina and enters the CCD camera.

2. The integrated system for measuring corneal curvature and eye parameters according to claim 1, characterized in that: The microarray reflector forms a set pattern on the microarray reflector by controlling part of the reflectors to flip.

3. The integrated system for measuring corneal curvature and eye parameters according to claim 1, characterized in that: The measuring module further comprises: a focusing lens arranged behind the zoom lens group, for measuring corneal curvature.

4. The integrated system for measuring corneal curvature and eye parameters according to claim 1, characterized in that: The detector is also connected with an acquisition card and a computer device.

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