CN114366019B - System and method for measuring eyeball parameters - Google Patents

The invention provides a system and a method for measuring eyeball parameters, which comprises the following steps: the low coherence measurement unit is used for obtaining a low coherence interference signal spectrum related to the thickness of each tissue in the eye axis direction of the eyeball to be measured, and the low coherence interference signal spectrum comprises a plurality of interference peaks; the long coherence measurement unit is used for obtaining a long coherence interference signal spectrum with approximate equal amplitude; an interference signal synchronization unit for synchronizing the low coherence measurement unit and the long coherence measurement unit; the eyeball imaging unit is used for acquiring a surface image of an eyeball to be detected; the signal processing and control unit is respectively electrically connected with the low coherence measurement unit, the long coherence measurement unit and the eyeball imaging unit, and measures the distance between low coherence interference peaks in the low coherence interference signal spectrum according to the long coherence interference signal spectrum so as to obtain eyeball parameters in the eye axis direction of the eyeball to be measured; and simultaneously, analyzing the surface image of the eyeball to be detected according to a digital image processing technology to obtain the transverse eyeball parameters of the eyeball to be detected.

一种眼球参数的测量系统及方法System and method for measuring eyeball parameters

技术领域technical field

本发明涉及光学测量技术领域，特别是涉及一种眼球参数的测量系统及方法。The invention relates to the technical field of optical measurement, in particular to a system and method for measuring eyeball parameters.

背景技术Background technique

青光眼、近视眼、白内障等临床上的很多眼科疾病都会导致人眼球参数的变化，目前，根据国家卫生健康委员会数据显示，2018年我国儿童青少年总体近视率为53.6％。近视程度与眼轴长度呈正相关，是区别真性近视与假性近视的重要依据。对儿童和青少年的眼轴长度进行监测有助于预防和治疗近视及其引发的眼科疾病。同时，随着科学技术的不断发展，白内障手术方式逐渐由传统的复明手术转变为效果更好的屈光手术，但我国仍有20％～40％的白内障患者术后的预测屈光力误差大于±0.50D，而眼轴长度测量是影响误差的关键因素，术前准确的眼球参数测量随之愈发的重要，眼轴长度测量的准确性密切影响到术后的屈光误差。Many clinical ophthalmic diseases, such as glaucoma, myopia, and cataract, can lead to changes in eyeball parameters. At present, according to data from the National Health and Health Commission, the overall myopia rate of children and adolescents in my country in 2018 was 53.6%. The degree of myopia is positively correlated with the axial length of the eye, which is an important basis for distinguishing true myopia from pseudomyopia. Monitoring the axial length of children and adolescents can help prevent and treat myopia and its related eye diseases. At the same time, with the continuous development of science and technology, cataract surgery has gradually changed from traditional vision restoration surgery to better refractive surgery, but there are still 20% to 40% of cataract patients in my country whose postoperative predicted refractive power error is greater than ±0.50 D, while the measurement of axial length is the key factor affecting the error, the accurate measurement of eyeball parameters before operation becomes more and more important, and the accuracy of axial length measurement closely affects the refractive error after operation.

角膜和瞳孔同样是人眼重要的组成部分，角膜是人眼前面的一种透明屈光介质，为人眼提供约70％左右的屈光力，测量角膜曲率的大小不仅可以指导角膜屈光度矫正手术、判定人眼有无散光而且可以为人们佩戴角膜接触镜提供科学依据；瞳孔直径的大小除了作为判别眼部疾病的依据，也能间接反映出人体生理和心理的变化过程。因此，在眼科疾病的预防、诊断和治疗过程中，获得精准的眼球参数，如眼轴长度、角膜厚度、前房深度、晶状体厚度、角膜曲率、瞳孔直径等眼球参数显得尤为重要。The cornea and the pupil are also important components of the human eye. The cornea is a transparent refractive medium in front of the human eye, providing about 70% of the refractive power for the human eye. Measuring the curvature of the cornea can not only guide corneal diopter correction surgery, but also determine human Whether the eyes have astigmatism can provide a scientific basis for people to wear contact lenses; the size of the pupil diameter can not only be used as the basis for distinguishing eye diseases, but also indirectly reflect the changing process of human physiology and psychology. Therefore, in the prevention, diagnosis and treatment of ophthalmic diseases, it is particularly important to obtain accurate ocular parameters, such as axial length, corneal thickness, anterior chamber depth, lens thickness, corneal curvature, pupil diameter and other ocular parameters.

现有的眼球参数测量手段按技术不同分为超声测量方法和光学测量方法两种。超声测量方法具有价格低廉和携带便捷的优点，但是由于分辨力较低、需要接触式检测和操作复杂等因素，在测量前需要进行眼表麻醉，测量探头接触角膜形成的压力会影响测量结果，其测量精度较低，且易损伤、感染角膜。同时测量结果易受操作者主观影响且只能实现眼球视轴方向参数的测量即眼轴长度、角膜厚度等；相对而言，光学测量方法具有非接触、高精度和操作简单等优势，测量结果的精确度和重复性优于超声测量方法，同时避免了超声测量方法中的一些局限性，如避免了易感染性。传统的光学测量方法主要是通过时域光学相干断层扫描测量眼轴长度，这种一维光学成像生物测量方法存在扫描速率慢、无法固视、只能实现眼球视轴方向参数测量等局限性。The existing eyeball parameter measurement methods are divided into ultrasonic measurement method and optical measurement method according to different technologies. Ultrasonic measurement method has the advantages of low price and convenient portability, but due to factors such as low resolution, need for contact detection and complicated operation, ocular surface anesthesia is required before measurement, and the pressure formed by the measurement probe contacting the cornea will affect the measurement results. Its measurement accuracy is low, and it is easy to damage and infect the cornea. At the same time, the measurement results are subject to the subjective influence of the operator and can only measure the parameters of the visual axis of the eye, such as eye axis length and corneal thickness. Relatively speaking, the optical measurement method has the advantages of non-contact, high precision and simple operation. The accuracy and repeatability of the method is better than that of the ultrasonic measurement method, while avoiding some limitations of the ultrasonic measurement method, such as avoiding the susceptibility to infection. The traditional optical measurement method is mainly to measure the axial length of the eye through time-domain optical coherence tomography. This one-dimensional optical imaging biometric method has limitations such as slow scanning rate, inability to fix eyesight, and only the measurement of eyeball visual axis direction parameters.

针对以上问题，亟需一种能够同时对眼球的轴向参数和横向参数进行测量的系统和方法。In view of the above problems, there is an urgent need for a system and method capable of simultaneously measuring the axial parameters and lateral parameters of the eyeball.

发明内容Contents of the invention

本发明的目的是提供一种眼球参数的测量系统及方法，解决现有的眼球参数测量手段不能同时测量眼球轴向参数和横向参数的问题。The object of the present invention is to provide a measurement system and method for eyeball parameters, which solves the problem that the existing eyeball parameter measurement means cannot measure eyeball axial parameters and lateral parameters at the same time.

为实现上述目的，本发明提供了一种眼球参数的测量系统，测量系统包括：In order to achieve the above object, the present invention provides a measurement system of eyeball parameters, the measurement system includes:

低相干测量单元，用于获得与待测眼球眼轴方向各组织的厚度相关的低相干干涉信号谱，所述低相干干涉信号谱中包括若干个干涉峰；The low-coherence measurement unit is used to obtain a low-coherence interference signal spectrum related to the thickness of each tissue in the eye axis direction of the eyeball to be measured, and the low-coherence interference signal spectrum includes several interference peaks;

长相干测量单元，用于获得近似等幅值的长相干干涉信号谱；A long-term coherent measurement unit, used to obtain approximately equal-amplitude long-term coherent interference signal spectrum;

干涉信号同步单元，用于同步所述低相干测量单元和所述长相干测量单元；an interference signal synchronization unit for synchronizing the low-coherence measurement unit and the long-coherence measurement unit;

眼球成像单元，用于获取待测眼球的表面图像；An eyeball imaging unit, configured to acquire a surface image of the eyeball to be tested;

信号处理及控制单元，分别与所述低相干测量单元、所述长相干测量单元和所述眼球成像单元电连接；所述信号处理及控制单元用于：根据所述长相干干涉信号谱，测量所述低相干干涉信号谱中各低相干干涉峰之间的距离，并根据所述距离计算待测眼球眼轴方向的眼球参数；根据数字图像处理技术对待测眼球的表面图像进行分析，得到待测眼球横向的眼球参数。The signal processing and control unit is electrically connected to the low-coherence measurement unit, the long-coherence measurement unit and the eyeball imaging unit respectively; the signal processing and control unit is used for: measuring according to the long-coherence interference signal spectrum The distance between the low-coherence interference peaks in the low-coherence interference signal spectrum, and calculate the eyeball parameters in the axial direction of the eyeball to be measured according to the distance; analyze the surface image of the eyeball to be tested according to the digital image processing technology, and obtain the Eyeball parameters in the horizontal direction of the eyeball.

可选地，所述低相干测量单元包括：Optionally, the low-coherence measurement unit includes:

宽带光源，与所述信号处理及控制单元电连接，用于发出宽带光信号；A broadband light source, electrically connected to the signal processing and control unit, for sending out a broadband optical signal;

引导光源，与所述信号处理及控制单元电连接，用于发出引导光信号；a guiding light source, electrically connected to the signal processing and control unit, for sending out a guiding light signal;

第一单模光纤耦合器，所述第一单模光纤耦合器的输入端分别与所述宽带光源和所述引导光源连接，所述第一单模光纤耦合器的输出端输出耦合光信号；A first single-mode fiber coupler, the input end of the first single-mode fiber coupler is respectively connected to the broadband light source and the guide light source, and the output end of the first single-mode fiber coupler outputs a coupled optical signal;

第二单模光纤耦合器，与所述第一单模光纤耦合器的输出端连接，用于将所述耦合光信号分成低相干参考光信号、低相干零点光信号和低相干样品光信号；所述低相干参考光信号经过所述干涉信号同步单元进行光信号延迟后，返回到第二单模光纤耦合器中；所述低相干零点光信号经法拉第镜反射回到第二单模光纤耦合器中，并与返回的低相干参考光信号发生干涉，产生参考零点干涉信号；所述低相干样品光信号经待测眼球各组织界面反射后返回第二单模光纤耦合器中，并与返回的低相干参考光信号发生干涉，产生参考样品干涉信号；A second single-mode fiber coupler, connected to the output end of the first single-mode fiber coupler, for dividing the coupled optical signal into a low-coherence reference optical signal, a low-coherence zero-point optical signal, and a low-coherence sample optical signal; The low-coherence reference optical signal is returned to the second single-mode fiber coupler after the optical signal is delayed by the interference signal synchronization unit; the low-coherence zero-point optical signal is reflected by the Faraday mirror and returned to the second single-mode fiber coupling and interferes with the returned low-coherence reference optical signal to generate a reference zero-point interference signal; the low-coherence sample optical signal is reflected by each tissue interface of the eyeball to be tested and returns to the second single-mode fiber coupler, and is combined with the returned The low-coherence reference optical signal interferes to generate a reference sample interference signal;

平衡光电探测器，与所述第二单模光纤耦合器连接，接收所述参考零点干涉信号和所述参考样品干涉信号，并分别将所述参考零点干涉信号和所述参考样品干涉信号转化为电信号传输给所述信号处理及控制单元。a balanced photodetector connected to the second single-mode fiber coupler, receiving the reference zero interference signal and the reference sample interference signal, and converting the reference zero interference signal and the reference sample interference signal into The electrical signal is transmitted to the signal processing and control unit.

可选地，所述低相干测量单元还包括：依次设置在低相干参考光信号光路上的第一偏振控制器、光纤波分复用器和光纤准直器；Optionally, the low-coherence measurement unit further includes: a first polarization controller, a fiber wavelength division multiplexer, and a fiber collimator sequentially arranged on the optical path of the low-coherence reference optical signal;

依次设置在低相干零点光信号光路上的第一光纤匹配器和法拉第镜；The first optical fiber matcher and the Faraday mirror are sequentially arranged on the low-coherence zero-point optical signal optical path;

依次设置在低相干样品光信号光路上的第二偏振控制器、第二光纤匹配器和眼球焦点追踪模块。A second polarization controller, a second optical fiber matcher and an eye focus tracking module are sequentially arranged on the light path of the low-coherence sample optical signal.

可选地，所述眼球焦点追踪模块包括：Optionally, the eye focus tracking module includes:

伺服电机和设置在所述伺服电机上的调焦透镜，所述伺服电机与所述信号处理及控制单元控制连接，所述伺服电机用于驱动所述调焦透镜进行轴向运动。A servo motor and a focus lens arranged on the servo motor, the servo motor is connected to the signal processing and control unit for control, and the servo motor is used to drive the focus lens to move axially.

可选地，所述长相干测量单元包括：Optionally, the long-term coherent measurement unit includes:

窄带光源，与所述信号处理及控制单元电连接，用于发出窄带光信号；A narrow-band light source, electrically connected to the signal processing and control unit, for sending out narrow-band optical signals;

第三单模光纤耦合器，与所述窄带光源的输出端连接，用于将所述窄带光信号分成长相干参考光信号和长相干测量光信号；所述长相干参考光信号经过所述反射膜回到第三单模光纤耦合器中；所述长相干测量光信号经过干涉信号同步单元进行光信号延迟后，返回到第三单模光纤耦合器中，并与返回的长相干参考光信号发生干涉，产生参考测量干涉信号；The third single-mode fiber coupler is connected to the output end of the narrowband light source, and is used to divide the narrowband optical signal into a long coherent reference optical signal and a long coherent measurement optical signal; the long coherent reference optical signal passes through the reflection The film returns to the third single-mode fiber coupler; the long-term coherent measurement optical signal is returned to the third single-mode fiber coupler after the optical signal is delayed by the interference signal synchronization unit, and is combined with the returned long-term coherent reference optical signal Interference occurs to generate a reference measurement interference signal;

Si光电探测器，与所述第三单模光纤耦合器连接，接收所述参考测量干涉信号，并将所述参考测量干涉信号转化为电信号传输给所述信号处理及控制单元。The Si photodetector is connected to the third single-mode fiber coupler, receives the reference measurement interference signal, converts the reference measurement interference signal into an electrical signal, and transmits it to the signal processing and control unit.

可选地，所述长相干测量单元还包括：设置在长相干参考光信号的光路上的反射膜；Optionally, the long-term coherence measurement unit further includes: a reflective film arranged on the optical path of the long-term coherent reference optical signal;

依次设置在长相干测量光信号的光路上的光纤波分复用器和光纤准直器。An optical fiber wavelength division multiplexer and an optical fiber collimator are sequentially arranged on the optical path of the long coherent measurement optical signal.

可选地，所述干涉信号同步单元包括：底座、转动圆盘、直流无刷盘式电机、若干个调整架、若干个中空屋脊棱镜反射镜和平面反射镜；Optionally, the interference signal synchronization unit includes: a base, a rotating disk, a DC brushless disk motor, several adjustment frames, several hollow roof prism mirrors and plane mirrors;

所述转动圆盘和所述直流无刷盘式电机均设置在所述底座上，且所述转动圆盘设于所述直流无刷盘式电机上；所述直流无刷盘式电机与所述信号处理及控制单元控制连接，所述直流无刷盘式电机用于驱动所述转动圆盘旋转；Both the rotating disk and the DC brushless disk motor are arranged on the base, and the rotating disk is arranged on the DC brushless disk motor; the DC brushless disk motor and the DC brushless disk motor The signal processing and control unit is controlled and connected, and the DC brushless disc motor is used to drive the rotating disc to rotate;

所述若干个调整架均匀固定在所述转动圆盘上，若干个中空屋脊棱镜反射镜分别安装在若干个调整架上，所述中空屋脊棱镜用于折射入射的光信号；The several adjustment mounts are evenly fixed on the rotating disk, and the several hollow roof prism reflectors are respectively installed on the several adjustment mounts, and the hollow roof prisms are used to refract the incident optical signal;

所述平面反射镜设置在所述底座上，用于反射入射的光信号。The plane reflector is arranged on the base for reflecting the incident optical signal.

可选地，所述眼球成像单元包括：Optionally, the eyeball imaging unit includes:

照明板，通过照明板控制电路与所述信号处理及控制单元控制连接，用于产生成像光线，并将所述成像光线照射在待测眼球上；The lighting board is controlled and connected with the signal processing and control unit through the lighting board control circuit, and is used to generate imaging light and irradiate the imaging light on the eyeball to be tested;

依次设置在待测眼球反射光线的光路上的分光镜和成像物镜，用于在成像物镜上生成待测眼球的表面图像；A spectroscope and an imaging objective lens are sequentially arranged on the optical path of the reflected light of the eyeball to be tested, for generating a surface image of the eyeball to be tested on the imaging objective lens;

图像传感器，与所述成像物镜平行设置，并与所述信号处理及控制单元电连接，所述图像传感器用于采集待测眼球的表面图像。An image sensor is arranged parallel to the imaging objective lens and is electrically connected to the signal processing and control unit, the image sensor is used to collect the surface image of the eyeball to be tested.

另一方面，本发明还提供了一种眼球参数的测量方法，应用如前文所述的测量系统，包括以下步骤：On the other hand, the present invention also provides a method for measuring eyeball parameters, using the measurement system as described above, comprising the following steps:

利用低相干测量单元获得与待测眼球眼轴方向各组织的厚度相关的低相干干涉信号谱，所述低相干干涉信号谱中包括若干个干涉峰；Using a low-coherence measurement unit to obtain a low-coherence interference signal spectrum related to the thickness of each tissue in the axial direction of the eyeball to be measured, the low-coherence interference signal spectrum includes several interference peaks;

利用长相干测量单元获得近似等幅值的长相干干涉信号谱；Using the long-term coherent measurement unit to obtain approximately equal-amplitude long-term coherent interference signal spectrum;

利用眼球成像单元获得待测眼球的表面图像；Using the eyeball imaging unit to obtain a surface image of the eyeball to be tested;

根据所述长相干干涉信号谱，测量所述低相干干涉信号谱中各低相干干涉峰之间的距离，并根据所述距离计算待测眼球眼轴方向的眼球参数；According to the long-coherence interference signal spectrum, measure the distance between the low-coherence interference peaks in the low-coherence interference signal spectrum, and calculate the eyeball parameters in the eye axis direction of the eyeball to be measured according to the distance;

根据数字图像处理技术对待测眼球的表面图像进行分析，测量得到待测眼球横向的眼球参数。According to the digital image processing technology, the surface image of the eyeball to be tested is analyzed, and the lateral eyeball parameters of the eyeball to be tested are measured.

可选地，所述测量方法还包括：利用干涉信号同步单元同步所述低相干测量单元和所述长相干测量单元。Optionally, the measurement method further includes: using an interference signal synchronization unit to synchronize the low-coherence measurement unit and the long-coherence measurement unit.

根据本发明提供的具体发明内容，本发明公开了以下技术效果：According to the specific content of the invention provided by the invention, the invention discloses the following technical effects:

本发明提供的一种眼球参数的测量系统及方法，包括：低相干测量单元，用于获得与待测眼球眼轴方向各组织的厚度相关的低相干干涉信号谱，所述低相干干涉信号谱中包括若干个干涉峰；长相干测量单元，用于获得近似等幅值的长相干干涉信号谱；干涉信号同步单元，同步所述低相干测量单元和所述长相干测量单元；眼球成像单元，用于获取待测眼球的表面图像；信号处理及控制单元，分别与所述低相干测量单元、所述长相干测量单元和所述眼球成像单元电连接，并根据所述长相干干涉信号谱，测量低相干干涉信号谱中各低相干干涉峰之间的距离，以得到待测眼球眼轴方向的眼球参数；根据数字图像处理技术对待测眼球的表面图像进行分析，得到待测眼球横向的眼球参数。本发明提供的测量系统及测量方法采用光学干涉测量法完成对待测眼球视轴方向上的参数的测量，同时根据成像原理及数字图像处理技术对待测眼球横向的参数进行了测量。A system and method for measuring eyeball parameters provided by the present invention, including: a low-coherence measurement unit, used to obtain a low-coherence interference signal spectrum related to the thickness of each tissue in the axial direction of the eyeball to be measured, the low-coherence interference signal spectrum Including several interference peaks; long-term coherence measurement unit, used to obtain approximately equal-amplitude long-term coherence interference signal spectrum; interference signal synchronization unit, synchronizing the low-coherence measurement unit and the long-term coherence measurement unit; eyeball imaging unit, for obtaining the surface image of the eyeball to be tested; the signal processing and control unit is electrically connected to the low coherence measurement unit, the long coherence measurement unit and the eyeball imaging unit respectively, and according to the long coherence interference signal spectrum, Measure the distance between the low-coherence interference peaks in the low-coherence interference signal spectrum to obtain the eyeball parameters in the axial direction of the eyeball to be tested; analyze the surface image of the eyeball to be tested according to digital image processing technology to obtain the eyeball parameters in the horizontal direction of the eyeball to be tested . The measuring system and measuring method provided by the invention use optical interferometry to measure the parameters in the visual axis direction of the eyeball to be tested, and measure the horizontal parameters of the eyeball to be tested according to the imaging principle and digital image processing technology.

另外，由于通过一个旋转式光学延迟线同步低相干测量单元与长相干测量单元，使二者产生的干涉信号具有同步性，因此通过干涉测距法，即计算相邻两个低相干干涉峰之间长相干干涉信号的周期数，就可以得出两个相邻弱相干干涉峰的距离，进而准确获得人眼视轴方向各组织层的厚度信息。In addition, since the low-coherence measurement unit and the long-coherence measurement unit are synchronized through a rotating optical delay line, the interference signals generated by the two are synchronized. Therefore, through the interference ranging method, that is, to calculate the distance between two adjacent low-coherence interference peaks The period number of the long coherence interference signal can be used to obtain the distance between two adjacent weak coherence interference peaks, and then the thickness information of each tissue layer in the visual axis direction of the human eye can be accurately obtained.

进一步的，在干涉系统光路中采用了法拉第镜，能最大程度地减小光纤中由热扰动和机械扰动引起的偏振态的变化，便于干涉系统偏振态的控制，进而提高了干涉信号强度以及测量结果的信噪比。Further, the Faraday mirror is used in the optical path of the interference system, which can minimize the change of the polarization state caused by thermal and mechanical disturbances in the optical fiber, facilitate the control of the polarization state of the interference system, and thus improve the interference signal strength and measurement The signal-to-noise ratio of the result.

进一步的，本发明采用旋转式光学延迟线，通过直流无刷盘式电机控制转动圆盘上的中空屋脊棱镜反射镜转动，改变参考光路的光程，实现人眼不同层面的扫描，通过一次扫描，获取人眼视轴方向各层厚度信息；其中空屋脊棱镜反射镜是由两块直角棱镜和一块长方形基片构成，具有极高的表面平整度和良好的光学性能，在整个光谱范围内具有优越的透光性和极低的荧光强度。同时直角棱镜斜面上镀有带金属保护层的银膜，在可见光和近红外波段都具有高反射率，两个棱镜的斜面相对放置，且二面角成90°。中空屋脊棱镜反射镜可以反射从外部入射到棱镜斜边的光，与平面反射镜不同之处是反射光线仍然和入射光线平行，避免了光束干涉的影响。而且，本发明所采用的直流无刷盘式电机，带有内置编码器，用于精确位移标定；电机具有结构紧凑，高动态，高效率且运行平稳的特点，同时盘式结构对电机与底座的连接提供了方便。Further, the present invention adopts a rotating optical delay line, controls the rotation of the hollow roof prism mirror on the rotating disk through a DC brushless disk motor, changes the optical path of the reference optical path, and realizes scanning at different levels of the human eye. , to obtain the thickness information of each layer in the direction of the visual axis of the human eye; the hollow roof prism reflector is composed of two right-angle prisms and a rectangular substrate, which has extremely high surface flatness and good optical performance, and has Superior light transmission and extremely low fluorescence intensity. At the same time, the oblique surface of the rectangular prism is coated with a silver film with a metal protective layer, which has high reflectivity in the visible light and near-infrared bands. The oblique surfaces of the two prisms are placed opposite each other, and the dihedral angle is 90°. The hollow roof prism reflector can reflect the light incident from the outside to the hypotenuse of the prism. The difference from the flat reflector is that the reflected light is still parallel to the incident light, which avoids the influence of beam interference. Moreover, the DC brushless disc motor used in the present invention has a built-in encoder for accurate displacement calibration; the motor has the characteristics of compact structure, high dynamics, high efficiency and stable operation, and the disc structure has a great impact on the motor and the base. The connection provides convenience.

附图说明Description of drawings

为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。In order 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 in the embodiments. Obviously, the accompanying drawings in the following description are only some of the present invention. Embodiments, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without any creative effort.

图1为本发明实施例1提供的一种眼球参数的测量系统的结构框图；Fig. 1 is the structural block diagram of the measurement system of a kind of eyeball parameter that the embodiment 1 of the present invention provides;

图2为本发明实施例2提供的一种眼球参数的测量方法的流程图；Fig. 2 is a flow chart of a method for measuring eyeball parameters provided by Embodiment 2 of the present invention;

图3为本发明实施例3提供的眼球参数的测量系统的结构示意图；Fig. 3 is the structural representation of the measurement system of eyeball parameter provided by embodiment 3 of the present invention;

图4为本发明实施例3提供的旋转式光学延迟线的结构示意图；FIG. 4 is a schematic structural diagram of a rotary optical delay line provided by Embodiment 3 of the present invention;

图5为本发明实施例3提供的眼球焦点追踪模块的结构示意图；5 is a schematic structural diagram of an eye focus tracking module provided by Embodiment 3 of the present invention;

图6为实施例3提供的测量方法中眼球视轴方向和横向不同组织界面结构图；Fig. 6 is the structural diagram of different tissue interfaces in the eyeball visual axis direction and lateral direction in the measurement method provided by embodiment 3;

图7(a)为本发明实施例3提供的低相干测量单元生成的低相干干涉信号谱；Figure 7(a) is the low-coherence interference signal spectrum generated by the low-coherence measurement unit provided in Embodiment 3 of the present invention;

图7(b)为本发明实施例3提供的长相干测量单元生成的长相干干涉信号谱；Fig. 7(b) is the long-term coherent interference signal spectrum generated by the long-term coherent measurement unit provided in Embodiment 3 of the present invention;

图8为本发明实施例3提供的测量方法中根据长相干干涉信号测量眼球组织视轴方向各分界面干涉峰间距的示意图。Fig. 8 is a schematic diagram of measuring the interferometric peak distance of each interface in the visual axis direction of the eyeball tissue according to the long-term coherent interference signal in the measurement method provided by Embodiment 3 of the present invention.

符号说明：Symbol Description:

1：宽带光源；2：引导光源；3：窄带光源；4：Si光电探测器；5：平衡光电探测器；6：2*1单模光纤耦合器；7：3*3单模光纤耦合器；8：光纤波分复用器；9：2*2单模光纤耦合器；10：光纤准直器；11：旋转式光学延迟线；12：平面反射镜；13：第一双桨光纤偏振控制器；14：第二双桨光纤偏振控制器；15：第一光纤匹配器；16：法拉第镜；17：第二光纤匹配器；18：调焦透镜；19：步进电机；20：分光镜；21：成像物镜；22：CMOS；23：照明板；24：待测人眼；25：照明板控制电路；26：电源模块；27：信号处理及控制单元；28：激光器驱动模块；29：计算机；30：底座；31：转动圆盘；32：中空屋脊棱镜反射镜；33：直流无刷盘式电机；34：调整架；35：成像单元；36：人眼光学系统模型。1: broadband light source; 2: guided light source; 3: narrowband light source; 4: Si photodetector; 5: balanced photodetector; 6: 2*1 single-mode fiber coupler; 7: 3*3 single-mode fiber coupler ;8: Fiber wavelength division multiplexer; 9: 2*2 single-mode fiber coupler; 10: Fiber collimator; 11: Rotary optical delay line; 12: Plane mirror; 13: The first double paddle fiber polarization Controller; 14: second scull fiber optic polarization controller; 15: first fiber matching device; 16: Faraday mirror; 17: second fiber matching device; 18: focusing lens; 19: stepping motor; 20: splitting mirror; 21: imaging objective lens; 22: CMOS; 23: lighting board; 24: human eye to be tested; 25: lighting board control circuit; 26: power supply module; 27: signal processing and control unit; 28: laser driver module; 29 : computer; 30: base; 31: rotating disc; 32: hollow roof prism reflector; 33: DC brushless disc motor; 34: adjustment frame; 35: imaging unit; 36: human eye optical system model.

具体实施方式Detailed ways

下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。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, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

本发明的目的是提供一种眼球参数的测量系统及方法，解决现有的眼球参数测量手段不能同时测量眼球轴向参数和横向参数的问题。The object of the present invention is to provide a measurement system and method for eyeball parameters, which solves the problem that the existing eyeball parameter measurement means cannot measure eyeball axial parameters and lateral parameters at the same time.

为使本发明的上述目的、特征和优点能够更加明显易懂，下面结合附图和具体实施方式对本发明作进一步详细的说明。In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

实施例1：Example 1:

如图1所示，本发明提供了一种眼球参数的测量系统，测量系统包括：As shown in Figure 1, the present invention provides a kind of measurement system of eyeball parameter, and measurement system comprises:

低相干测量单元，用于获得与待测眼球眼轴方向各组织的厚度相关的低相干干涉信号谱，所述低相干干涉信号谱中包括若干个干涉峰；The low-coherence measurement unit is used to obtain a low-coherence interference signal spectrum related to the thickness of each tissue in the eye axis direction of the eyeball to be measured, and the low-coherence interference signal spectrum includes several interference peaks;

长相干测量单元，用于获得近似等幅值的长相干干涉信号谱；A long-term coherent measurement unit, used to obtain approximately equal-amplitude long-term coherent interference signal spectrum;

干涉信号同步单元，用于同步所述低相干测量单元和所述长相干测量单元；an interference signal synchronization unit for synchronizing the low-coherence measurement unit and the long-coherence measurement unit;

眼球成像单元，用于获取待测眼球的表面图像；An eyeball imaging unit, configured to acquire a surface image of the eyeball to be tested;

信号处理及控制单元，分别与所述低相干测量单元、所述长相干测量单元和所述眼球成像单元电连接；所述信号处理及控制单元用于：根据所述长相干干涉信号谱，测量所述低相干干涉信号谱中各低相干干涉峰之间的距离，并根据所述距离计算待测眼球眼轴方向的眼球参数；根据数字图像处理技术对待测眼球的表面图像进行分析，得到待测眼球横向的眼球参数。The signal processing and control unit is electrically connected to the low-coherence measurement unit, the long-coherence measurement unit and the eyeball imaging unit respectively; the signal processing and control unit is used for: measuring according to the long-coherence interference signal spectrum The distance between the low-coherence interference peaks in the low-coherence interference signal spectrum, and calculate the eyeball parameters in the axial direction of the eyeball to be measured according to the distance; analyze the surface image of the eyeball to be tested according to the digital image processing technology, and obtain the Eyeball parameters in the horizontal direction of the eyeball.

为了提高系统抗干扰性和光路路径的方便性，在光路部分采用了单膜光纤耦合，用单模光纤来作为光路的传导介质；为了便于调整光路，在所述低相干系统中采用了He-Ne激光器作为引导光，He-Ne激光器所发出的光与SLED宽带光源发出的低相干光通过光纤耦合器后进入系统。具体来说，低相干测量单元又包括：In order to improve the anti-interference of the system and the convenience of the optical path, a single-membrane optical fiber coupling is used in the optical path, and a single-mode fiber is used as the transmission medium of the optical path; in order to facilitate the adjustment of the optical path, He- The Ne laser is used as the guiding light, and the light emitted by the He-Ne laser and the low-coherence light emitted by the SLED broadband light source enter the system through the fiber coupler. Specifically, the low-coherence measurement unit includes:

宽带光源，本实施例中选用SLED宽带光源，与所述信号处理及控制单元电连接，用于发出宽带光信号；A broadband light source, an SLED broadband light source is selected in this embodiment, and is electrically connected to the signal processing and control unit for sending a broadband optical signal;

引导光源，本实施例中选用He-Ne激光器，与所述信号处理及控制单元电连接，用于发出引导光信号；A guiding light source, in this embodiment, a He-Ne laser is selected, electrically connected to the signal processing and control unit, and used to send a guiding light signal;

第一单模光纤耦合器，本实施例中选用2*1单模光纤耦合器，所述2*1单模光纤耦合器的两个输入端分别与所述宽带光源和所述引导光源连接，所述第一单模光纤耦合器的输出端输出耦合光信号；The first single-mode fiber coupler, a 2*1 single-mode fiber coupler is selected in this embodiment, and the two input ends of the 2*1 single-mode fiber coupler are respectively connected to the broadband light source and the guide light source, The output end of the first single-mode fiber coupler outputs a coupled optical signal;

第二单模光纤耦合器，本实施例中选用3*3单模光纤耦合器，与所述第一单模光纤耦合器的输出端连接，用于将所述耦合光信号分成低相干参考光信号、低相干零点光信号和低相干样品光信号；所述低相干参考光信号经过所述干涉信号同步单元进行光信号延迟后，返回到第二单模光纤耦合器中；所述低相干零点光信号经法拉第镜反射回到第二单模光纤耦合器中，并与返回的低相干参考光信号发生干涉，产生参考零点干涉信号；所述低相干样品光信号经待测眼球各组织界面反射后返回第二单模光纤耦合器中，并与返回的低相干参考光信号发生干涉，产生参考样品干涉信号；The second single-mode fiber coupler, a 3*3 single-mode fiber coupler is selected in this embodiment, and is connected to the output end of the first single-mode fiber coupler, and is used to divide the coupled optical signal into low-coherence reference light signal, a low-coherence zero-point optical signal, and a low-coherence sample optical signal; the low-coherence reference optical signal is returned to the second single-mode fiber coupler after the optical signal is delayed by the interference signal synchronization unit; the low-coherence zero-point The light signal is reflected back to the second single-mode fiber coupler through the Faraday mirror, and interferes with the returned low-coherence reference light signal to generate a reference zero-point interference signal; the low-coherence sample light signal is reflected by the interface of each tissue of the eyeball to be tested Then return to the second single-mode fiber coupler, and interfere with the returned low-coherence reference optical signal to generate a reference sample interference signal;

平衡光电探测器，与所述第二单模光纤耦合器连接，接收所述参考零点干涉信号和所述参考样品干涉信号，并分别将所述参考零点干涉信号和所述参考样品干涉信号转化为电信号传输给所述信号处理及控制单元。a balanced photodetector connected to the second single-mode fiber coupler, receiving the reference zero interference signal and the reference sample interference signal, and converting the reference zero interference signal and the reference sample interference signal into The electrical signal is transmitted to the signal processing and control unit.

进一步的结构，低相干测量单元还包括：依次设置在低相干参考光信号光路上的第一偏振控制器、光纤波分复用器和光纤准直器；In a further structure, the low-coherence measurement unit also includes: a first polarization controller, a fiber wavelength division multiplexer and a fiber collimator arranged sequentially on the optical path of the low-coherence reference optical signal;

依次设置在低相干零点光信号光路上的第一光纤匹配器和法拉第镜；The first optical fiber matcher and the Faraday mirror are sequentially arranged on the low-coherence zero-point optical signal optical path;

依次设置在低相干样品光信号光路上的第二偏振控制器、第二光纤匹配器和眼球焦点追踪模块。A second polarization controller, a second optical fiber matcher and an eye focus tracking module are sequentially arranged on the light path of the low-coherence sample optical signal.

由于测量光在人眼中传输中，眼组织对光的吸收特性，导致光信号的衰减，使人眼各组织界面反射信号降低，不利于干涉信号的采集，因此，利用伺服电机及调焦透镜设计了眼球焦点追踪模块，眼球焦点追踪模块包括：During the transmission of measuring light in the human eye, the absorption characteristics of the eye tissue lead to the attenuation of the optical signal, which reduces the reflection signal of the tissue interface of the human eye, which is not conducive to the collection of interference signals. Therefore, the servo motor and focusing lens are used to design The eye focus tracking module, the eye focus tracking module includes:

伺服电机和设置在所述伺服电机上的调焦透镜，所述伺服电机与所述信号处理及控制单元控制连接，所述伺服电机用于驱动所述调焦透镜进行轴向运动。A servo motor and a focus lens arranged on the servo motor, the servo motor is connected to the signal processing and control unit for control, and the servo motor is used to drive the focus lens to move axially.

为了与低相干测量单元区分，并且满足相干长度大于干涉信号同步单元光程变化量要求，所述长相干测量单元包括：In order to distinguish it from the low-coherence measurement unit and meet the requirement that the coherence length is greater than the optical path change of the interference signal synchronization unit, the long-coherence measurement unit includes:

窄带光源，与所述信号处理及控制单元电连接，用于发出窄带光信号；A narrow-band light source, electrically connected to the signal processing and control unit, for sending out narrow-band optical signals;

第三单模光纤耦合器，本实施例中选用2*2单模光纤耦合器，与所述窄带光源的输出端连接，用于将所述窄带光信号分成长相干参考光信号和长相干测量光信号；所述长相干参考光信号经过所述反射膜回到第三单模光纤耦合器中；所述长相干测量光信号经过干涉信号同步单元3进行光信号延迟后，返回到第三单模光纤耦合器中，并与返回的长相干参考光信号发生干涉，产生参考测量干涉信号；The third single-mode fiber coupler, a 2*2 single-mode fiber coupler is selected in this embodiment, connected to the output end of the narrowband light source, and used to divide the narrowband optical signal into a long coherent reference optical signal and a long coherent measurement optical signal; the long-term coherent reference optical signal is returned to the third single-mode fiber coupler through the reflective film; the long-term coherent measurement optical signal is returned to the third single-mode optical fiber coupler after the optical signal is delayed by the interference signal synchronization unit 3 In the mode fiber coupler, it interferes with the returned long-term coherent reference optical signal to generate a reference measurement interference signal;

Si光电探测器，与所述第三单模光纤耦合器连接，接收所述参考测量干涉信号，并将所述参考测量干涉信号转化为电信号传输给所述信号处理及控制单元。The Si photodetector is connected to the third single-mode fiber coupler, receives the reference measurement interference signal, converts the reference measurement interference signal into an electrical signal, and transmits it to the signal processing and control unit.

进一步的结构，长相干测量单元还包括：设置在长相干参考光信号的光路上的反射膜；In a further structure, the long-term coherent measurement unit also includes: a reflective film arranged on the optical path of the long-term coherent reference optical signal;

依次设置在长相干测量光信号的光路上的光纤波分复用器和光纤准直器。An optical fiber wavelength division multiplexer and an optical fiber collimator are sequentially arranged on the optical path of the long coherent measurement optical signal.

可选地，所述干涉信号同步单元包括：底座、转动圆盘、直流无刷盘式电机、若干个调整架、若干个中空屋脊棱镜反射镜和平面反射镜；Optionally, the interference signal synchronization unit includes: a base, a rotating disk, a DC brushless disk motor, several adjustment frames, several hollow roof prism mirrors and plane mirrors;

所述转动圆盘和所述直流无刷盘式电机均设置在所述底座上，且所述转动圆盘设于所述直流无刷盘式电机上；所述直流无刷盘式电机与所述信号处理及控制单元控制连接，所述直流无刷盘式电机用于驱动所述转动圆盘旋转；Both the rotating disk and the DC brushless disk motor are arranged on the base, and the rotating disk is arranged on the DC brushless disk motor; the DC brushless disk motor and the DC brushless disk motor The signal processing and control unit is controlled and connected, and the DC brushless disc motor is used to drive the rotating disc to rotate;

所述若干个调整架均匀固定在所述转动圆盘上，若干个中空屋脊棱镜反射镜分别安装在若干个调整架上，所述中空屋脊棱镜用于折射入射的光信号；The several adjustment mounts are evenly fixed on the rotating disk, and the several hollow roof prism reflectors are respectively installed on the several adjustment mounts, and the hollow roof prisms are used to refract the incident optical signal;

所述平面反射镜设置在所述底座上，用于反射入射的光信号。The plane reflector is arranged on the base for reflecting the incident optical signal.

便于采集待测眼球的表面图像，所述眼球成像单元包括：To facilitate collecting the surface image of the eyeball to be tested, the eyeball imaging unit includes:

照明板，通过照明板控制电路与所述信号处理及控制单元控制连接，用于产生成像光线，并将所述成像光线照射在待测眼球上；The lighting board is controlled and connected with the signal processing and control unit through the lighting board control circuit, and is used to generate imaging light and irradiate the imaging light on the eyeball to be tested;

依次设置在待测眼球反射光线的光路上的分光镜和成像物镜，用于在成像物镜上生成待测眼球的表面图像；A spectroscope and an imaging objective lens are sequentially arranged on the optical path of the reflected light of the eyeball to be tested, for generating a surface image of the eyeball to be tested on the imaging objective lens;

图像传感器，与所述成像物镜平行设置，并与所述信号处理及控制单元电连接，所述图像传感器用于采集待测眼球的表面图像。An image sensor is arranged parallel to the imaging objective lens and is electrically connected to the signal processing and control unit, the image sensor is used to collect the surface image of the eyeball to be tested.

实施例2：Example 2:

如图2所示，对应于实施例1的一种眼球参数的测量系统，本发明还提供了一种眼球参数的测量方法，应用如实施例1所述的测量系统，包括以下步骤：As shown in Figure 2, corresponding to the measuring system of a kind of eyeball parameter of embodiment 1, the present invention also provides a kind of measuring method of eyeball parameter, application is as described in embodiment 1 measuring system, comprises the following steps:

S1、利用低相干测量单元获得与待测眼球眼轴方向各组织的厚度相关的低相干干涉信号谱，所述低相干干涉信号谱中包括若干个干涉峰；S1. Using a low-coherence measurement unit to obtain a low-coherence interference signal spectrum related to the thickness of each tissue in the eye axis direction of the eye to be measured, the low-coherence interference signal spectrum includes several interference peaks;

S2、利用长相干测量单元获得近似等幅值的长相干干涉信号谱；S2. Using the long-term coherent measurement unit to obtain approximately equal-amplitude long-term coherent interference signal spectra;

S3、利用眼球成像单元获得待测眼球的表面图像；S3. Using the eyeball imaging unit to obtain a surface image of the eyeball to be tested;

S4、根据所述长相干干涉信号谱，测量所述低相干干涉信号谱中各低相干干涉峰之间的距离，并根据所述距离计算待测眼球眼轴方向的眼球参数；S4. According to the long-coherence interference signal spectrum, measure the distance between the low-coherence interference peaks in the low-coherence interference signal spectrum, and calculate the eyeball parameters in the eye axis direction of the eyeball to be measured according to the distance;

S5、根据数字图像处理技术对待测眼球的表面图像进行分析，测量得到待测眼球横向的眼球参数。S5. Analyze the surface image of the eyeball to be tested according to the digital image processing technology, and measure and obtain eyeball parameters in the horizontal direction of the eyeball to be tested.

为了使低相干测量单元和长相干测量单元产生的干涉信号具有同步性，能够采用干涉测距法计算低相干干涉峰之间的距离，利用干涉信号同步单元同步所述低相干测量单元和所述长相干测量单元。In order to synchronize the interference signals generated by the low-coherence measurement unit and the long-coherence measurement unit, the distance between the low-coherence interference peaks can be calculated by using the interferometric ranging method, and the interference signal synchronization unit is used to synchronize the low-coherence measurement unit and the long-coherence measurement unit. Coherent measurement unit.

实施例3：Example 3:

如图3所示，本实施例中使用一个具体的例子详细说明并验证本发明提供的测量方法达到的效果。As shown in FIG. 3 , a specific example is used in this embodiment to describe and verify the effect achieved by the measurement method provided by the present invention.

选择波长为1060nm，3dB带宽为60nm的SLED宽带光源1，当然也可以用符合要求的宽带光源，SLED宽带光源1发出的低相干光与He-Ne激光器2发出的引导光通过2*1单模光纤耦合器6后，再经过3*3单模光纤耦合器7分成测量光源参考光路、测量光源零点光路和测量光源样品光路；其中测量光源样品光路经过第一双桨光纤偏振控制器13、第二光纤匹配器17后，再经过可移动调焦透镜18后聚焦到眼组织各个分界面并返回；测量光源参考光路经过第二双桨光纤偏振控制器14光纤波分复用器8后进入光纤准直器10，光纤准直器10出射的光进入旋转式光学延迟线11，旋转式光学延迟线的结构如图4所示，光纤准直器10出射的光经过旋转式光学延迟线11上分布的中空屋脊棱镜反射镜32后射向安装在底座30上的平面反射镜12，经平面反射镜12反射的光按原光路返回，与人眼组织各界面反射光在3*3单模光纤耦合器7中发生干涉，干涉信号由平衡光电探测器5接收；测量光源零点光路上设置有第一光纤匹配器15，法拉第镜16，入射光经过法拉第镜16反射后，反射光按原光路返回，在3*3单模光纤耦合器7中与测量光源参考光路返回的光产生干涉，干涉信号同样由平衡光电探测器5接收；平衡探测器5接收到的干涉信号经过信号处理及控制器27进行信号处理后输出到计算机29。Choose the SLED broadband light source 1 with a wavelength of 1060nm and a 3dB bandwidth of 60nm. Of course, you can also use a broadband light source that meets the requirements. The low-coherent light emitted by the SLED broadband light source 1 and the guided light emitted by the He-Ne laser 2 pass through 2*1 single-mode After the fiber coupler 6, the 3*3 single-mode fiber coupler 7 is divided into the measurement light source reference light path, the measurement light source zero point light path and the measurement light source sample light path; wherein the measurement light source sample light path passes through the first double-blade fiber optic polarization controller 13, the second After the second optical fiber matching device 17, after passing through the movable focusing lens 18, it is focused on each interface of the eye tissue and returned; Collimator 10, the light emitted by the fiber collimator 10 enters the rotary optical delay line 11, the structure of the rotary optical delay line is shown in Figure 4, the light emitted by the fiber collimator 10 passes through the rotary optical delay line 11 The distributed hollow roof prism reflector 32 shoots to the plane reflector 12 installed on the base 30, the light reflected by the plane reflector 12 returns according to the original optical path, and the reflected light from each interface of the human eye tissue passes through the 3*3 single-mode optical fiber Interference occurs in the coupler 7, and the interference signal is received by the balanced photodetector 5; a first optical fiber matcher 15 and a Faraday mirror 16 are arranged on the zero-point optical path of the measuring light source. After the incident light is reflected by the Faraday mirror 16, the reflected light returns according to the original optical path , in the 3*3 single-mode fiber coupler 7, interferes with the light returned by the reference light path of the measuring light source, and the interference signal is also received by the balanced photodetector 5; the interference signal received by the balanced detector 5 is processed by the signal processing and controller 27 The signal is processed and then output to the computer 29 .

长相干光源采用窄带光源3，为了与低相干光源区分，并且满足相干长度大于光学延迟线光程变化量要求，选择波长为1310nm，带宽为1.1GHz的DFB激光器；窄带光源3发出的光经过2*2单模光纤耦合器9将光路分为长相干干涉系统的测量光路和参考光路，其中参考光路被单模光纤末端的反射膜反射回到2*2单模光纤耦合器9中，而测量光路经过光纤波分复用器8及光纤准直器10后进入旋转式光学延迟线11，经过旋转式光学延迟线11上分布的中空屋脊棱镜反射镜32后射向安装在底座30上的平面反射镜12，经平面反射镜12反射的光按原光路返回，反射的光与参考光路返回光在2*2单模光纤耦合器9中发生干涉，干涉信号由Si光电探测器4接收，探测器接收的干涉信号经信号处理及控制器27进行处理，信号处理后形成幅值近似相等的正弦波。The long-coherent light source adopts narrow-band light source 3. In order to distinguish it from low-coherence light source and meet the requirement that the coherence length is greater than the optical path change of the optical delay line, a DFB laser with a wavelength of 1310nm and a bandwidth of 1.1GHz is selected; the light emitted by the narrow-band light source 3 passes through 2 *2 The single-mode fiber coupler 9 divides the light path into the measurement light path and the reference light path of the long coherent interference system, wherein the reference light path is reflected back into the 2*2 single-mode fiber coupler 9 by the reflective film at the end of the single-mode fiber, and the measurement The optical path enters the rotary optical delay line 11 after passing through the optical fiber wavelength division multiplexer 8 and the optical fiber collimator 10, passes through the hollow roof prism reflector 32 distributed on the rotary optical delay line 11, and then shoots to the plane installed on the base 30 Reflector 12, the light reflected by the plane reflector 12 returns according to the original optical path, and the reflected light interferes with the return light of the reference optical path in the 2*2 single-mode fiber coupler 9, and the interference signal is received by the Si photodetector 4 and detected The interference signal received by the device is processed by the signal processing and controller 27, and after the signal processing, a sine wave with approximately equal amplitude is formed.

成像单元35包含照明板23、分光镜20、成像物镜21、CMOS模块22，待测人眼24，照明板23与照明板控制电路25连接，照明板控制电路25控制照明板光源，照明板发出的光照射到待测人眼24，通过人眼角膜返射的光经过分光镜20分光，在成像物镜21上成像，通过CMOS模块22采集人眼图像，传输到信号处理及控制器27及计算机29，通过数字图像处理技术及干涉测距技术实现眼球角膜曲率等横向参数测量。The imaging unit 35 includes a lighting board 23, a beam splitter 20, an imaging objective lens 21, a CMOS module 22, and a human eye 24 to be tested. The light irradiates the human eye 24 to be tested, and the light reflected by the cornea of the human eye is split by the beam splitter 20 and imaged on the imaging objective lens 21. The image of the human eye is collected by the CMOS module 22 and transmitted to the signal processing and controller 27 and the computer. 29. Realize the measurement of lateral parameters such as eyeball corneal curvature through digital image processing technology and interferometric ranging technology.

所述低相干测量单元与长相干测量单元，共用一个旋转式光学延迟线11，产生的干涉信号具有同步性，因此通过干涉测距法，计算相邻两个低相干干涉峰之间长相干干涉信号的周期数，就可以得出两个相邻弱相干干涉峰的距离，进而获得人眼视轴方向各组织层的厚度信息。The low-coherence measurement unit and the long-coherence measurement unit share a rotary optical delay line 11, and the interference signals generated are synchronous, so the long-coherence interference signal between two adjacent low-coherence interference peaks is calculated by the interferometric ranging method The number of cycles, the distance between two adjacent weak coherence interference peaks can be obtained, and then the thickness information of each tissue layer in the direction of the visual axis of the human eye can be obtained.

系统中通过采用光学干涉法，干涉测距法及数字图像处理技术，并设计了眼球焦点追踪模块，如图5所示，眼球焦点追踪模块包含调焦透镜18、伺服电机19，人眼光学系统模型36，在本实施例中，人眼光学系统模型36为待测人眼24，其中调焦透镜18是可移动的，通过信号处理及控制器27控制伺服电机19以设定的速度进行轴向运动，控制调焦透镜18与第二光纤匹配器17入射光之间的距离，达到调节入射光在人眼组织各个层面聚焦的目的，进而提高干涉信号强度及系统信噪比。提高了系统信噪比及测量精度；采用中空屋脊棱镜反射镜和直流盘式无刷电机设计的旋转式光学延迟线提高了系统的测量速度。The system adopts optical interferometry, interferometric distance measurement and digital image processing technology, and designs the eyeball focus tracking module, as shown in Figure 5, the eyeball focus tracking module includes focusing lens 18, servo motor 19, human eye optical system Model 36, in this embodiment, the human eye optical system model 36 is the human eye 24 to be tested, wherein the focusing lens 18 is movable, and the servo motor 19 is controlled by the signal processing and the controller 27 to move the axis at a set speed. To control the distance between the focusing lens 18 and the incident light of the second optical fiber matcher 17, to adjust the focus of the incident light at all levels of human eye tissue, and then improve the interference signal strength and system signal-to-noise ratio. The signal-to-noise ratio and measurement accuracy of the system are improved; the rotating optical delay line designed with a hollow roof prism mirror and a DC disc brushless motor improves the measurement speed of the system.

如图6所示为眼球视轴方向和横向不同组织界面结构图；其中AL眼轴长度，CCT为角膜厚度，AD为前房深度，LT为晶状体厚度，VT为玻璃体厚度，PD为瞳孔直径，WTW为白到白距离，K为角膜曲率。Figure 6 shows the structural diagram of different tissue interfaces in the visual axis direction and transverse direction of the eyeball; where AL is the axial length of the eye, CCT is the thickness of the cornea, AD is the depth of the anterior chamber, LT is the thickness of the lens, VT is the thickness of the vitreous body, and PD is the diameter of the pupil. WTW is the white-to-white distance, and K is the corneal curvature.

如图7所示为本实施例中提供的测量系统生成的干涉信号谱，其中图7(a)为长相干测量单元生成的长相干干涉波形图，由于长相干测量单元采用的光源光谱线宽窄，输出波形近似等幅值正弦波形，图7(b)为示波器采集到的低相干测量单元产生的眼球视轴方向各组织层的干涉波形图，因为各组织层反射信号的强度不同，所以生成的干涉信号幅值不同。图8所示，是根据长相干干涉信号测量眼球组织视轴方向各分界面干涉峰间距的示意图。As shown in Figure 7, it is the interference signal spectrum generated by the measurement system provided in this embodiment, wherein Figure 7 (a) is the long-term coherent interference waveform diagram generated by the long-term coherent measurement unit, because the light source spectral line width adopted by the long-term coherent measurement unit is narrow , the output waveform is approximately equal-amplitude sinusoidal waveform. Figure 7(b) is the interference waveform of each tissue layer in the direction of the visual axis of the eyeball produced by the low-coherence measurement unit collected by the oscilloscope. Because the intensity of the reflected signal of each tissue layer is different, the generated The amplitude of the interference signal is different. As shown in FIG. 8 , it is a schematic diagram of measuring the interferometric peak distance of each interface in the visual axis direction of the eyeball tissue according to the long-term coherent interference signal.

技术中的程序部分可以被认为是以可执行的代码和/或相关数据的形式而存在的“产品”或“制品”，通过计算机可读的介质所参与或实现的。有形的、永久的储存介质可以包括任何计算机、处理器、或类似设备或相关的模块所用到的内存或存储器。例如，各种半导体存储器、磁带驱动器、磁盘驱动器或者类似任何能够为软件提供存储功能的设备。The program part in the technology can be regarded as a "product" or "article" existing in the form of executable code and/or related data, participated in or realized through a computer-readable medium. Tangible, permanent storage media may include the internal memory or storage used by any computer, processor, or similar device or related modules. For example, various semiconductor memories, tape drives, disk drives, or any similar device that provides storage for software.

所有软件或其中的一部分有时可能会通过网络进行通信，如互联网或其他通信网络。此类通信可以将软件从一个计算机设备或处理器加载到另一个。例如：从视频目标检测设备的一个服务器或主机计算机加载至一个计算机环境的硬件平台，或其他实现系统的计算机环境，或与提供目标检测所需要的信息相关的类似功能的系统。因此，另一种能够传递软件元素的介质也可以被用作局部设备之间的物理连接，例如光波、电波、电磁波等，通过电缆、光缆或者空气等实现传播。用来载波的物理介质如电缆、无线连接或光缆等类似设备，也可以被认为是承载软件的介质。在这里的用法除非限制了有形的“储存”介质，其他表示计算机或机器“可读介质”的术语都表示在处理器执行任何指令的过程中参与的介质。All or portions of the Software may from time to time communicate over a network, such as the Internet or other communication network. Such communications may load software from one computer device or processor to another. For example: a server or host computer of a video object detection device is loaded into a hardware platform of a computer environment, or other computer environment for implementing the system, or a system with similar functions related to providing information required for object detection. Therefore, another medium that can transmit software elements can also be used as a physical connection between local devices, such as light waves, radio waves, electromagnetic waves, etc., and can be transmitted through cables, optical cables, or air. The physical medium used for carrier waves, such as electrical cables, wireless connections, or fiber optic cables, can also be considered a medium for carrying software. As used herein, unless restricted to tangible "storage" media, other terms referring to computer or machine "readable media" mean media that participate in the execution of any instructions by a processor.

本文中应用了具体个例对本发明的原理及实施方式进行了阐述，以上实施例的说明只是用于帮助理解本发明的方法及其核心思想；本领域的技术人员应该理解，上述本发明的各模块或各步骤可以用通用的计算机装置来实现，可选地，它们可以用计算装置可执行的程序代码来实现，从而，可以将它们存储在存储装置中由计算装置来执行，或者将它们分别制作成各个集成电路模块，或者将它们中的多个模块或步骤制作成单个集成电路模块来实现。本发明不限制于任何特定的硬件和软件的结合。In this paper, specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; those skilled in the art should understand that each of the above-mentioned embodiments of the present invention The modules or each step can be realized by a general-purpose computer device. Optionally, they can be realized by a program code executable by the computing device, so that they can be stored in a storage device to be executed by the computing device, or they can be separately It can be realized by making individual integrated circuit modules, or by making multiple modules or steps among them into a single integrated circuit module. The invention is not limited to any specific combination of hardware and software.

同时，对于本领域的一般技术人员，依据本发明的思想，在具体实施方式及应用范围上均会有改变之处。综上所述，本说明书内容不应理解为对本发明的限制。At the same time, for those skilled in the art, according to the idea of the present invention, there will be changes in the specific implementation and application scope. In summary, the contents of this specification should not be construed as limiting the present invention.