CN113229777A

CN113229777A - Visual quality analyzer

Info

Publication number: CN113229777A
Application number: CN202110373581.3A
Authority: CN
Inventors: 尉佩; 陈文光
Original assignee: Shanghai Mediworks Precision Instrument Co ltd
Current assignee: Shanghai Mediworks Precision Instrument Co ltd
Priority date: 2021-04-07
Filing date: 2021-04-07
Publication date: 2021-08-10
Anticipated expiration: 2041-04-07
Also published as: CN113229777B

Abstract

The invention relates to a visual quality analyzer which is characterized by comprising an OCT module and a whole-eye aberration measurement module which are combined together through a dichroic mirror, wherein a collimated laser beam emitted by the OCT module is used as a light source of the whole-eye aberration measurement module. The invention takes the collimated light beam emitted by the fiber collimator of the OCT system as the incident laser of the OCT imaging system and the aberration measurement system, the return light of the light after passing through the eyes passes through the dichroic mirror, one part of the return light returns to the OCT system for three-dimensional imaging and eye axis measurement, and the other part of the return light passes through the aberration measurement system for morphological analysis and aberration measurement. Compared with the prior art, the invention has the advantages that: the system is simple, has complete functions, and can simultaneously realize parameter measurement of corneal aberration, total ocular aberration, ocular axis length and the like.

Description

Visual quality analyzer

Technical Field

The invention relates to a visual quality analyzer, and belongs to the technical field of visual quality analysis.

Background

A fundamental problem of visual optics is how to accurately measure the imaging quality of the optical system of the human eye. The primary optical quality can be described by the two optical defects of defocus and astigmatism that can be corrected by a spherical cylindrical lens. However, in addition to defocus and astigmatism, the human eye also has other higher order aberrations. In 1997, D.R. Williams et al, Rochester university, USA, for the first time, analyzed the influence of high order aberration correction of human eyes on visual function by adaptive optics technology, improved the contrast sensitivity of tested eyes by more than 6 times by statically compensating for high order aberration of human eyes, and obtained "super vision" (super vision) of resolving 55c/deg sinusoidal grating optotypes.

Excimer laser corneal surface ablation (PRK) and excimer laser corneal in-situ abrasion and inlay (LASIK) for correcting refraction, as well as the recent phacoemulsification surgery and crystalloid refractive surgery for treating cataract, require accurate measurement of high-grade aberrations of human eyes, and can perform total aberration compensation after personalized compensation design of the whole eye. Therefore, an accurate aberration measuring apparatus is very necessary.

The human eye aberration is a result contributed by the cornea and the crystal together, the forms of all tissues are respectively measured, the aberration of each part is calculated, and then the accurate customized compensation scheme can be obtained by combining the measurement of the whole eye aberration. The OCT technology is an imaging technology which is rapidly developed in the last decade, and the OCT technology detects back scattering signals of different depth layers of biological tissues to incident weak coherent light by utilizing the basic principle of a weak coherent light interferometer, and two-dimensional or three-dimensional structural images of the biological tissues can be obtained by scanning. The application of OCT in medical diagnosis has the advantages of no damage, high resolution, and capability of performing functional imaging, and is therefore considered to be one of the most promising imaging techniques.

The OCT technique is applied to human eye tomography, two-dimensional and three-dimensional tissue forms of cornea and crystal and the length of an eye axis can be obtained, and the disposable vision quality related parameters can be obtained by combining the whole-eye aberration measurement technique.

Disclosure of Invention

The purpose of the invention is: an apparatus is provided for performing human eye tomography that combines OCT and wavefront measurement techniques.

In order to achieve the above object, the present invention provides a visual quality analyzer, which includes an OCT module and a binocular aberration measurement module combined together by a dichroic mirror, wherein a collimated laser beam emitted from the OCT module is used as a light source of the binocular aberration measurement module, and wherein:

the OCT module comprises a laser, laser emitted by the laser is divided into two beams of light with a fixed proportion, one beam of light enters a reference arm light path and then enters an optical fiber coupler to be used as reference light of the OCT module, and the other beam of light enters a sample arm light path and then is emitted; when eye axis and a tomography image are measured, light emitted from a sample arm light path is transmitted into human eyes to carry out multi-dimensional scanning imaging after passing through a two-dimensional vibrating mirror, a convergence system, a dichroic mirror I and a dichroic mirror II; human eye backscattering signals are received by the optical fiber coupler after returning to a sample arm light path, are interfered with reference light and then enter the balance detector, and the acquisition and processing system synthesizes tomography by utilizing the output of the balance detector; when the full-eye wave aberration is measured, light emitted from a sample arm light path enters a human eye through the two-dimensional vibrating mirror, the dichroic mirror I and the dichroic mirror II, light spots converged at the eye ground are scattered through the eye ground, emitted with full-eye information and then enter the full-eye aberration measuring module through the dichroic mirror, the full-eye aberration measuring module collects light spot data and sends the light spot data to the collecting and processing system, and the full-eye wave front aberration is obtained through processing.

Preferably, the system further comprises a positioning shooting system, the positioning shooting system records a corneal topography of the pupil, the white-to-white and the placido ring of the human eye projected to the eye surface of the human eye, and the total corneal aberration is calculated by using the corneal topography.

Preferably, a backlight plate 302 is used to achieve uniform illumination of the backside of the placido ring.

Preferably, the positioning shooting system comprises a visible light source, and light beams emitted by the visible light source project the patterns of the sighting target plate onto a second reflecting mirror which can be adjusted up and down through a first reflecting mirror and a second illuminating system; light reflected by the reflecting mirror II is received by human eyes through the dichroic mirror III, the zoom optical system, the dichroic mirror I and the dichroic mirror II; the imaging sensor collects the eye surface information of the human eyes through the zoom optical system, and records the pupil, the white-to-white and the corneal topography projected to the eye surface of the human eyes by the placido ring of the human eyes.

Preferably, the OCT module employs swept-frequency OCT, frequency-domain OCT or time-domain OCT.

Preferably, the reference arm optical path includes a first circulator, light from the laser is input to the first circulator, light output by the first circulator is collimated by the first optical fiber collimator and then vertically incident on a third reflector, and light reflected by the third reflector and returned is incident on the optical fiber coupler as the reference light.

Preferably, the sample arm optical path includes a second circulator, light from the laser is input to the second circulator, and light emitted from the second circulator passes through the polarization controller and then is collimated and emitted to the two-dimensional galvanometer by the collimator after the polarization state is adjusted.

Preferably, the whole-eye aberration measurement module adopts a wavefront aberration measurement method of Hartmann-Shack or a sequential light displacement measurement method.

Preferably, the whole-eye aberration measurement module comprises an optical collimation system, scattered light returned by human eyes enters the optical collimation system through the dichroic mirror II, then collimated light beams enter a focusing system, the focusing system compensates refraction of the human eyes, then parallel light enters a micro-lens array through the collimation and beam expansion system, the micro-lens array divides light waves into small light beams, the small light beams are converged to the Hartmann wavefront sensor, light spot data acquired by the Hartmann wavefront sensor is sent to the acquisition and processing system, and whole-eye wavefront aberration is obtained through processing, wherein the focusing system realizes measurement of the whole-eye aberration according to different positions before and after refraction adjustment.

Preferably, the binocular disparity measuring module comprises a second zooming optical system, scattered light returned by human eyes is reflected by a second dichroic mirror and then enters the second zooming optical system, then is divided into two beams of light by a spectroscope, the two beams of light respectively enter a first linear array sensor and a second linear array sensor through a first converging system and a second converging system, the acquisition processing system respectively records x-direction sequence fundus facula position information and y-direction sequence fundus facula position information by using the first linear array sensor and the second linear array sensor, reconstructs the detected facula positions and calculates the binocular disparity, wherein refraction information is recorded by adjusting the front and back position compensation of the second zooming optical system;

or the whole-eye aberration measurement module comprises a second zooming optical system, scattered light returned by human eyes is reflected by a second dichroic mirror and then enters the second zooming optical system, and then enters the area array sensor through a third converging system, and the acquisition processing system constructs whole-eye wavefront aberration according to sequence light distribution detected by the area array sensor.

The invention takes the collimated light beam emitted by the fiber collimator of the OCT system as the incident laser of the OCT imaging system and the aberration measurement system, the return light of the light after passing through the eyes passes through the dichroic mirror, one part of the return light returns to the OCT system for three-dimensional imaging and eye axis measurement, and the other part of the return light passes through the aberration measurement system for morphological analysis and aberration measurement. Compared with the prior art, the invention has the advantages that: the system is simple, has complete functions, and can simultaneously realize parameter measurement of corneal aberration, total ocular aberration, ocular axis length and the like.

Drawings

FIG. 1 is a schematic diagram of a convergence system of a vision quality analyzer according to embodiment 1 (a wavefront aberration measuring method of Hartmann-Shack is adopted by a total-eye aberration measuring module);

FIG. 2 is a schematic diagram of a vision quality analyzer after the convergence system has been removed (the whole-eye aberration measurement module employs Hartmann-Shack wavefront aberration measurement) as disclosed in example 1;

FIG. 3 is a schematic view of a placido ring;

fig. 4 is a schematic diagram of a convergence system in a vision quality analyzer according to embodiment 2 (sequential optical displacement measurement is used in the global eye aberration measurement module);

fig. 5 is a schematic diagram of a convergence system of a vision quality analyzer according to example 2 after being removed (sequential optical displacement measurement is used in the global eye aberration measurement module);

FIG. 6 is a schematic view of sequential spots;

fig. 7 to 9 are examples of different situations where sequential spots are detected;

FIG. 10 is a test calculation flow.

Detailed Description

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

Example 1

The vision quality analyzer provided by the embodiment combines OCT and wavefront measurement technologies, integrates a tomography light path and a wavefront measurement light path, and can quickly obtain all data such as full-eye aberration, corneal morphology, corneal aberration, ocular axis length and the like.

As shown in fig. 1, the visual quality analyzer of the present embodiment includes an OCT module 100, a whole-eye aberration measurement module 400, and a positioning and photographing system 200. The OCT module 100 and the eye-centered aberration measurement module 400 are combined together by the dichroic mirror 204, and the collimated laser beam emitted from the OCT module 100 can be used as a light source of the eye-centered aberration measurement module 400.

The positioning shooting system 200 comprises a visible light source 209, and light beams emitted by the visible light source 209 pass through a reflector 210 and

lighting systems

211 and 213 to project patterns of a sighting mark plate 212 onto a reflector 214. The light reflected by the reflecting mirror 214 is received by the human eye 300 via the dichroic mirror 208, the zoom optical system 206, the dichroic mirror 205, and the dichroic mirror 204. The mirror 214 may be adjusted up or down to achieve a process of defocusing the human eye 300 to be clear. The imaging sensor 207 acquires the ocular surface information of the human eye 300 through the optical system 206, records data such as pupils, white to white, and corneal topography projected to the ocular surface of the human eye 300 by the placido ring 301, and further calculates the total corneal aberration. Wherein a back uniform illumination of the placido ring 301 is achieved by the backlight plate 302. It should be noted that the total corneal aberration can also be calculated from the three-dimensional corneal topography scanned by the OCT module 100 as described below.

The OCT module 100 can use swept-frequency OCT (SS-OCT), frequency-domain OCT (SD-OCT) and time-domain OCT (TD-OCT), with the sample arm outputs being collimated beam outputs. This embodiment further illustrates the present invention by using a swept-frequency OCT (SS-OCT) as an example.

As shown in fig. 1, an OCT module 100 using swept-frequency OCT (SS-OCT) includes a swept-frequency laser 101, and a fiber coupler 102 splits the swept-frequency laser light emitted from the swept-frequency laser 101 into two beams of light of a fixed ratio, which are received by a circulator 103 and a circulator 104, respectively, to form a sample arm optical path and a reference arm optical path. The light output by the reference arm optical routing circulator 104 is collimated by the fiber collimator 106 and then perpendicularly incident on the mirror 107, and the return light is incident on the fiber coupler 108 as the reference light of the OCT module 100. Emergent light of the sample arm light path circulator 103 passes through a polarization controller 105, and then is collimated and emitted by a collimator 106 after the polarization state is adjusted.

When measuring the eye axis and the tomographic image, as shown in fig. 1, the converging system 202 is moved into the optical path to converge the collimated light in front of the human eye 300, and at this time, the light emitted from the collimator 106 is sequentially transmitted through the two-dimensional galvanometer 201, the converging system 202, the dichroic mirror 205, and the dichroic mirror 204 to the human eye 300 to perform multi-dimensional scanning imaging. The human eye 300 backscatter signal returns to the sample arm optical path, is received by the fiber coupler 108 through the exit end of the circulator 103, and after interfering with the light of the reference arm optical path, the reference light in the interference signal and the received human eye 300 backscatter signal are calculated in a ratio of 50: 50 are incident to the balance detector 109 in proportion, and the acquisition processing system 110 synthesizes tomography by using the output of the balance detector 109, so that anterior segment tomography and eye axis measurement can be realized.

When the total-eye wave aberration is measured, as shown in fig. 2, the converging system 202 is moved out of the optical path, the parallel light beams emitted from the collimator 106 are incident into the human eye 300 through the two-dimensional vibrating mirror 201, the dichroic mirror 205 and the dichroic mirror 204, and the light spots converged by the fundus are scattered by the fundus and then emitted with the total-eye information.

In the above technical solution, the two-dimensional galvanometer 201 can scan in the x direction and the y direction respectively.

The whole-eye aberration measurement module 500 in this embodiment employs the wavefront aberration measurement method of Hartmann-Shack. Scattered light returned by the human eye 300 is incident to an optical collimating system 501 through a dichroic mirror 204, then collimated light beams enter a focusing system 502, the focusing system 502 compensates refraction of the human eye, then parallel light is incident to a micro-lens array 504 through a collimating and beam expanding system 503, and the micro-lens array 504 divides light waves into small light beams which are converged to a Hartmann wavefront sensor 505. The light spot data acquired by the Hartmann wavefront sensor 505 is sent to the acquisition and processing system 110, and the wavefront aberration of the whole eye is obtained after processing. The focusing system 502 enables the measurement of the eye's total aberration according to different pre-and post-refractive adjustment positions.

Through the work of the modules, the aberration measurement, the corneal topography measurement, the anterior segment tomography and the eye axis measurement of the human eye in the full state can be realized.

Examples of different situations for detecting the sequence light spots are shown in fig. 7 to 9, wherein the sequence light spots simulate the human eye detection situation in a perfect way as shown in fig. 7, and simulate the human eye detection situation in a plus-minus degree way as shown in fig. 8 and 9.

The OCT module 100 as a tomographic imaging and axis measurement system may be replaced with a TD-OCT system or an SD-OCT system.

The test calculation flow of the present embodiment is shown in fig. 10.

Example 2

As shown in fig. 4 and 5, the present embodiment is different from embodiment 1 in that the total-eye aberration measuring module 400 employs a sequential optical displacement measurement method.

As shown in fig. 4, after the converging system 202 is removed, the collimated light emitted from the collimator 106 enters the human eye 300 via the two-dimensional galvanometer 201, the dichroic mirror 205, and the dichroic mirror 204. The two-dimensional galvanometer 201 adjusts the position of the collimated light for incidence into the eye as a serial arrangement (as shown in fig. 6). Each parallel light beam is incident to the fundus, the reflected light carrying the whole eye information is incident to the zooming optical system 401 after being reflected by the dichroic mirror 204, the reflected light is divided into two beams of light by the spectroscope 404, the two beams of light are respectively incident to the linear array sensor 403 and the linear array sensor 407 through the convergence system 405 and the convergence system 406, the acquisition processing system 110 respectively records the position information of the x-direction sequence fundus facula and the y-direction sequence fundus facula, the detected facula positions are reconstructed, and the whole eye wavefront aberration is calculated. In which refractive information can be recorded by adjusting the front-rear position compensation of the zoom optical system 401. The solution shown in fig. 4 further achieves accurate measurement by using a method of separately detecting the x and y directions.

The eye-covering aberration measurement module 400 may also use one area sensor 408 to detect the sequence fundus facula position information instead of the linear array sensor 403 and the linear array sensor 407 with reference to fig. 5, and the acquisition processing system 110 constructs the eye-covering wavefront aberration according to the sequence light distribution detected by the area sensor 408. Correspondingly, the zoom optical system 401 is used for focus compensation refraction.

Other structures and working manners of this embodiment are the same as those of embodiment 1, and are not described herein again.

Claims

1. The utility model provides a vision quality analyzer, its characterized in that includes OCT module and full-eye aberration measurement module that combines together through the dichroic mirror, and the collimated laser beam of OCT module outgoing is as the light source of full-eye aberration measurement module, wherein:

2. The visual quality analyzer of claim 1, further comprising a positioning camera system, wherein the positioning camera system records a corneal topography of a pupil, white-to-white, and placido ring of a human eye projected onto an ocular surface of the human eye, and the total corneal aberration is calculated using the corneal topography.

3. A visual quality analyzer according to claim 2, wherein a backlight plate 302 is used to achieve uniform illumination of the backside of the placido ring.

4. The vision quality analyzer of claim 2, wherein the positioning and shooting system comprises a visible light source, and a light beam emitted from the visible light source projects the pattern of the target plate onto a second reflector which can be adjusted up and down through a first reflector and a second illumination system; light reflected by the reflecting mirror II is received by human eyes through the dichroic mirror III, the zoom optical system, the dichroic mirror I and the dichroic mirror II; the imaging sensor collects the eye surface information of the human eyes through the zoom optical system, and records the pupil, the white-to-white and the corneal topography projected to the eye surface of the human eyes by the placido ring of the human eyes.

5. The visual quality analyzer of claim 1, wherein the OCT module employs swept-frequency OCT, frequency-domain OCT, or time-domain OCT.

6. The visual quality analyzer of claim 1, wherein the reference arm optical path comprises a first circulator, light from the first laser is input into the first circulator, light output by the first circulator is collimated by a first fiber collimator and then perpendicularly incident on a third reflector, and light returned by the third reflector is incident on the fiber coupler as the reference light.

7. The visual quality analyzer of claim 1, wherein the sample arm optical path includes a second circulator, light from the laser is input into the second circulator, and light emitted from the second circulator passes through the polarization controller and then is collimated by the collimator to be emitted to the two-dimensional galvanometer.

8. The vision quality analyzer of claim 1, wherein the whole-eye aberration measurement module employs Hartmann-Shack wavefront aberration measurement or sequential light displacement measurement.

9. The vision quality analyzer of claim 8, wherein the whole-eye aberration measuring module comprises an optical collimating system, the scattered light returned by the human eye enters the optical collimating system through the dichroic mirror two, then the collimated light beam enters the focusing system, the focusing system compensates the refraction of the human eye, and then the collimated light enters the micro-lens array through the collimation and beam expanding system, the micro-lens array divides the light wave into small light beams, the small light beams converge on the Hartmann wavefront sensor, the light spot data collected by the Hartmann wavefront sensor is sent to the collecting and processing system, and the whole-eye wavefront aberration is obtained through processing, wherein the focusing system adjusts the front and rear positions according to different refraction, so that the measurement of the whole-eye aberration is realized.

10. The vision quality analyzer of claim 8, wherein the eye-wide aberration measurement module comprises a second zoom optical system, the scattered light returned by the human eye is reflected by a second dichroic mirror and then enters the second zoom optical system, and then is split into two beams of light by a beam splitter, the two beams of light respectively enter the first linear array sensor and the second linear array sensor through the first converging system and the second converging system, the acquisition processing system respectively records the position information of the x-direction sequence fundus facula and the position information of the y-direction sequence fundus facula by using the first linear array sensor and the second linear array sensor, reconstructs the detected facula position and calculates the eye-wide wavefront aberration, wherein the refraction information is recorded by adjusting the front and back position compensation of the second zoom optical system;