JP2018111000A - Adjusting function evaluation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform evaluation on an adjusting function of an eye to be examined in detail.SOLUTION: An adjusting function evaluation device includes an adjusting stimulation imparting part, a measuring part, and an analyzing part. The adjusting stimulation imparting part imparts adjusting stimulation to an eye to the examined. The measuring part performs optical coherence tomography (OCT) for an object site in the eye to be examined including at least part of the crystalline lens. The analyzing part generates evaluation information on an adjusting function of the eye to be examined by analyzing data acquired by the OCT performed for the object site when at least the adjusting stimulation is imparted to the eye to be examined. The measuring part repeatedly performs the OCT for the object site at a predetermined repetition rate. The analyzing part obtains a time-series change in the shape of the crystalline lens based on a time-series change in the data acquired by the OCT repeatedly performed at the predetermined repetition rate, and generates evaluation information based on the time-series change in the shape.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an adjustment function evaluation apparatus for evaluating an adjustment function of an eye to be examined.

  The adjustment function (adjustment power) is very important in vision. The adjustment function is a function for focusing by changing the refractive power of the eye according to the distance of the object. The lens, chin band and ciliary body contribute to the change in the refractive power of the eye. The crystalline lens is a convex lens having a variable refractive power. Chin zonules are tissues that connect the lens and the ciliary body. The ciliary body is muscle tissue. When looking close, the ciliary muscle contracts and the chin band relaxes, thickening the crystalline lens and increasing the refractive power. On the other hand, when looking at the distance, the ciliary muscles relax and the chin zonules become tense so that the crystalline lens becomes thin and the refractive power decreases.

  The regulatory function is reduced by hardening of the lens due to aging or disease, fatigue of the ciliary muscle, and the like. In addition, as an abnormality of the regulation function, regulation tension, techno-stress ophthalmopathy (VDT syndrome), Valerie syndrome, regulation convulsions and the like are known.

  The evaluation of the adjustment function is performed based on the aberration amount in these two states by guiding the eye to be examined to the far point and the near point using an eye refractive power device or the like.

No. 2008/129991 JP 2000-126132 A

  In such a conventional technique, it has been difficult to structurally evaluate whether the tissue related to the regulation function is functioning properly. For example, in the prior art, it has not been possible to grasp how the lens that provides the adjustment force actually operates (that is, how the shape of the lens changes). Therefore, it was difficult to evaluate the regulation function in detail.

  An object of the present invention is to provide a technique capable of evaluating in detail the adjustment function of the eye to be examined.

  The adjustment function evaluation apparatus according to the embodiment includes an adjustment stimulus applying unit that applies adjustment stimulus to the eye to be examined, a measurement unit that performs optical coherence tomography on a target site in the eye to be examined including at least a part of the crystalline lens, and at least the above-mentioned An analysis unit that generates evaluation information related to the accommodation function of the eye to be examined by analyzing data acquired by the optical coherence tomography performed on the target region when the accommodation stimulus is applied to the eye to be examined. With. The measurement unit repeatedly executes optical coherence tomography for the target region at a predetermined repetition rate. The analysis unit obtains a time-series change of the crystalline form based on a time-series change of data acquired by optical coherence tomography repeatedly executed at the predetermined repetition rate, and based on the time-series change of the form The evaluation information is generated.

  According to the present invention, it is possible to evaluate the adjustment function of the eye to be examined in detail.

It is the schematic which shows the structural example of the adjustment function evaluation apparatus which concerns on embodiment. It is the schematic which shows the structural example of the adjustment function evaluation apparatus which concerns on embodiment. It is the schematic which shows the structural example of the adjustment function evaluation apparatus which concerns on embodiment. It is the schematic for demonstrating the operation example of the adjustment function evaluation apparatus which concerns on embodiment. It is the schematic for demonstrating the operation example of the adjustment function evaluation apparatus which concerns on embodiment. It is a flowchart which shows the operation example of the adjustment function evaluation apparatus which concerns on embodiment. It is a flowchart which shows the operation example of the adjustment function evaluation apparatus which concerns on embodiment. It is a flowchart which shows the operation example of the adjustment function evaluation apparatus which concerns on embodiment. It is a flowchart which shows the operation example of the adjustment function evaluation apparatus which concerns on embodiment.

  An adjustment function evaluation apparatus according to an embodiment will be described with reference to the drawings. The adjustment function evaluation apparatus according to this embodiment includes a function of applying an adjustment stimulus to the eye to be examined, a function of performing optical coherence tomography (OCT) of the eye to be examined, and data of the eye to be examined based on data acquired by OCT. And a function for evaluating the adjustment function.

<First Embodiment>
[Configuration of optical system]
The optical system provided in the adjustment function evaluation apparatus 1 according to the embodiment will be described. FIG. 1 shows an example of the configuration of the optical system. The adjustment function evaluation apparatus 1 includes a photographing optical system 10, a measurement optical system 30, a target projection optical system 50, and an interference optical system 60.

(Photographing optical system 10)
The photographing optical system 10 is used for photographing the anterior segment of the eye E. The photographing optical system 10 includes an anterior segment illumination light source 11, an objective lens 12, relay lenses 13 and 14, an imaging lens 15, and an image sensor 16.

  A plurality of anterior ocular segment illumination light sources 11 are arranged around the optical axis of the photographing optical system 10 and output light for illuminating the anterior segment. The light output from the anterior ocular segment illumination light source 11 is applied to the eye E and reflected by the anterior segment. This reflected light is detected by the image sensor 16 via the objective lens 12, the relay lens 13 and the imaging lens 15. The reflected light from the anterior eye part passes through beam splitters 70, 38, 24 and 43 described later and is guided to the image sensor 16.

  A beam splitter 24 is obliquely provided between the objective lens 12 and the relay lens 13. The beam splitter 24 synthesizes an optical path for photographing the anterior segment and an optical path for aligning the optical system with respect to the eye E. An alignment light source 21, an alignment target stop 22, and a lens 23 are provided in the optical path for performing alignment. The light output from the alignment light source 21 is reflected by the beam splitter 24 via the alignment target stop 22 and the lens 23, and is projected onto the anterior eye portion of the eye E through the objective lens 12. As in the prior art, the alignment of the imaging optical system 10 with respect to the eye E is executed based on the alignment target image reflected in the anterior segment image.

(Measurement optical system 30)
The measurement optical system 30 optically measures the optical characteristics of the eye E. The measurement optical system 30 of this embodiment measures the refractive power of the eye E. The measurement optical system 30 includes a measurement light source 31, a collimator lens 32, a ring translucent plate 33, a relay lens 34, a ring-shaped stop 35, a perforated prism 36, beam splitters 37 and 38, and the objective lens 12. A reflection mirror 39, a relay lens 40, a moving lens 41, a reflection mirror 42, a beam splitter 43, an imaging lens 15, and an image sensor 16. The measurement optical system 30 is configured to be coaxial with the imaging optical system 10 by beam splitters 38 and 43.

  The light output from the measurement light source 31 is converted into a parallel light beam by the collimator lens 32, converted into a ring-shaped light beam through the ring translucent plate 33, passed through the relay lens 34 and the ring-shaped diaphragm 35, It is reflected by the vacant prism 36, reflected by the beam splitter 37, reflected by the beam splitter 38, and applied to the eye E through the objective lens 12.

  The measurement light beam having a ring-shaped cross section irradiated on the eye E is reflected from the fundus and exits from the eye E. At this time, the cross-sectional shape of the measurement light beam is deformed by the influence of the eyeball optical system (cornea, crystalline lens, etc.).

  The measurement light beam emitted from the eye E passes through the objective lens 12, the beam splitters 38 and 37, passes through the light transmitting plate 36 a of the perforated prism 36, is reflected by the reflection mirror 39, and is supplied to the relay lens 40 and the moving lens 41. , Is reflected by the reflection mirror 42 and the beam splitter 43, and is detected by the image sensor 16 through the imaging lens 15. By analyzing the size and shape of the cross section of the detected measurement light beam, the aberration (sphericity, astigmatism, astigmatism axis, etc.) of the eye E is acquired. This process is executed in the same manner as in the prior art. That is, the adjustment function evaluation apparatus 1 functions as a refractometer.

(Target projection optical system 50)
The target projection optical system 50 presents various targets to the eye E. The target projection optical system 50 includes a target light source 51, a target plate 52, relay lenses 53 and 54, a reflection mirror 55, a beam splitter 38, and the objective lens 12. The target projection optical system 50 is configured to be coaxial with the imaging optical system 10 and the measurement optical system 30 by the beam splitter 38.

  The target plate 52 includes, for example, a turret plate and a transmissive liquid crystal display, and is configured such that various targets such as a fixation target and a visual target for visual acuity measurement can be selectively arranged with respect to the optical path. The light output from the target light source 51 is projected onto the fundus of the eye E through the above components of the target projection optical system 50.

  The target light source 51 and the target plate 52 are configured to be movable in the optical axis direction of the target projection optical system 50. Thereby, the visual recognition distance of the visual target by the eye E is changed. In other words, the target projection optical system 50 can be used to give an adjustment stimulus to the eye E.

(Interference optical system 60)
The interference optical system 60 is used for OCT of the eye E. The interference optical system 60 includes a light source unit 61, an optical fiber 62, a fiber coupler 63, an optical fiber 64, a collimator 65, an optical scanner 66, a focusing lens 67, a reflection mirror 68, and a relay lens 69. , A beam splitter 70, an objective lens 12, an optical fiber 71, a collimator 72, a condenser lens 73, a reference mirror 74, an optical fiber 75, and a detector 76.

  The OCT method applied in the embodiment is arbitrary. When the swept source method is applied, a wavelength swept light source capable of modulating the output wavelength at high speed is used as the light source unit 61, and a photodetector such as a balanced photodetector is used as the detection unit 76. When the spectral domain method is applied, a broadband light source (low coherent light source) is used as the light source unit 61, and a spectroscope that detects a spectrum is used as the detection unit 76. It is also possible to apply OCT of other methods such as a time domain method and a full field method (infras method).

  The fiber coupler 63 includes an optical fiber 62 that forms an optical path extending from the light source unit 61, an optical fiber 64 that forms part of the optical path toward the eye E, and an optical fiber that forms part of the optical path toward the reference mirror 74. 71 and an optical fiber 75 that forms an optical path toward the detection unit 76 are connected. The fiber coupler 63 has at least two functions. The first function is a function of dividing the light output from the light source unit 61 into light (measurement light) directed toward the eye E and light (reference light) directed toward the reference mirror 74. The second function is a function of synthesizing (interfering) the return light of the measurement light from the eye E and the return light from the reference mirror 74. The optical path of measurement light is called a measurement optical path or measurement arm, and the optical path of reference light is called a reference optical path or reference arm.

  The measurement arm is provided with an optical fiber 64, a collimator 65, an optical scanner 66, a focusing lens 67, a reflection mirror 68, a relay lens 69, a beam splitter 70, and the objective lens 12.

  The collimator 65 is provided at the end of the optical fiber 64, converts the measurement light emitted from the optical fiber 64 into a parallel light beam, and converts the return light of the measurement light from the eye E into a convergent light. 64 is incident.

  The optical scanner 66 changes the traveling direction of the measurement light in order to scan the eye E with the measurement light. The optical scanner 66 has, for example, a pair of uniaxial deflection devices or biaxial deflection devices. Examples of such an optical deflection device include a galvano scanner, a resonant mirror, a MEMS mirror, and a polygon mirror.

  The focusing lens 67 includes one or more lenses configured to be movable along the direction of the optical axis of the measurement light. As the focusing lens 67 moves, the focus position (beam waist position) of the measurement light changes.

  The beam splitter 70 combines the measurement arm and the optical path of the photographing optical system 10. Thereby, the photographing optical system 10, the measurement optical system 30, the target projection optical system 50, and the interference optical system 60 are coaxial with each other.

  The reference arm is provided with an optical fiber 71, a collimator 72, a condenser lens 73, and a reference mirror 74.

  The collimator 72 is provided at the end of the optical fiber 71, converts the reference light emitted from the optical fiber 71 into a parallel light beam, and converts the return light of the reference light from the reference mirror 74 into convergent light. 71 is incident.

  The condensing lens 73 forms an image of the reference light converted into a parallel light beam by the collimator 72 on the reflection surface of the reference mirror 74 and converts the return light of the reference light from the reference mirror 74 into a parallel light beam.

  The reference mirror 74 is disposed at a position optically conjugate with a portion of the eye E (which may be referred to as a target portion) to be subjected to OCT. The reference mirror 74 and the condensing lens 73 are configured to be movable integrally along the direction of the optical axis of the reference light. In this embodiment, the target region includes at least a part of the crystalline lens. That is, the target part includes at least a part of the crystalline lens, and may further include at least a part of another part (for example, the cornea, the iris, the vitreous body, and the like). Moreover, the ciliary body and the chin band may be included.

  In the configuration shown in FIG. 1, a single reference mirror 74 (first reference mirror) is provided, but a configuration in which two or more reference mirrors are provided can also be applied. For example, a beam splitter (for example, a half mirror) may be disposed between the collimator 72 and the reference mirror 74, and the condenser lens and the second reference mirror may be disposed in the optical path branched by the beam splitter. The second reference mirror is arranged at a position conjugate with the second target part of the eye E. This second target site is a site to be subjected to OCT together with a target site (first target site) related to the first reference mirror 74, and is, for example, a vitreous body, a retina, a choroid, or the like. The second reference mirror and the lens are movable along the direction of the optical axis of the branch optical path. Similarly, it is possible to provide three or more reference mirrors.

  The light output from the light source unit 61 is guided to the fiber coupler 63 through the optical fiber 62. The fiber coupler 63 divides this light into two.

  The light (measurement light) guided to the optical fiber 64 by the fiber coupler 63 is converted into a parallel light beam by the collimator 65, deflected by the optical scanner 66, reflected by the reflecting mirror 68 via the focusing lens 67, and relay lens. It is relayed by 69, reflected by the beam splitter 70, and irradiated to the eye E through the objective lens 12. The measurement light applied to the eye E is reflected and scattered at various tissues and tissue boundaries of the eye E. The return light of the measurement light from the eye E is guided backward through the measurement arm and returns to the fiber coupler 63. Note that the return light of the measurement light from the eye E includes reflected light and backscattered light from the eye E. In fluorescence imaging performed by administering a fluorescent agent, fluorescence generated by excitation with measurement light is included in the return light.

  On the other hand, the light (reference light) guided to the optical fiber 71 by the fiber coupler 63 is converted into a parallel light beam by the collimator 72 and imaged on the reflection surface of the reference mirror 74 by the condenser lens 73. The reference light reflected by the reference mirror 74 is converted into a parallel light beam by the condensing lens 73, converged by the collimator 72, enters the optical fiber 71, and returns to the fiber coupler 63 via the optical fiber 71. .

  In the case where two or more reference mirrors are provided, the reference light converted into a parallel light beam by the collimator 72 is divided into two or more reference lights by one or more beam splitters and reflected by the corresponding reference mirrors 2. The above reference light is combined by one or more beam splitters and is configured to enter the optical fiber 71 via the collimator 72.

  The fiber coupler 63 causes the return light of the measurement light from the eye E to interfere with the return light of the reference light from the reference mirror 74. The interference light generated thereby includes information on the target part (such as a crystalline lens) of the eye E conjugate with the reference mirror 74. When two or more reference mirrors are provided, the interference light includes information on two or more target parts conjugate with these reference mirrors. The interference light is guided to the detection unit 76 via the optical fiber 75. In the case of the swept source method, the detection unit 76 detects the intensity of the interference light. In the case of the spectral domain method, the detection unit 76 detects the spectral distribution of the interference light.

  Although not shown, the interference optical system 60 is provided with an attenuator and a polarization controller. The attenuator is provided in the optical fiber 71, for example, and adjusts the amount of reference light guided to the optical fiber 71. The polarization controller adjusts the polarization state of the reference light guided to the optical fiber 71 by, for example, applying stress from the outside to the optical fiber 71 having a loop shape. In addition to these, various known devices applicable to OCT can be provided in the interference optical system 60.

[Control system configuration]
A configuration example of the control system of the adjustment function evaluation apparatus 1 is shown in FIGS.

(Control unit 100)
The control system of the adjustment function evaluation apparatus 1 is configured around the control unit 100. The control unit 100 includes, for example, a processor, a storage device, a communication interface, and the like. The storage device stores computer programs and data for control and calculation. The control unit 100 is provided with a main control unit 110 and a storage unit 120.

(Main control unit 110)
The main control unit 110 controls each unit of the adjustment function evaluation device 1. For example, the main controller 110 operates the anterior segment illumination light source 11, the image sensor 16, the alignment light source 21, the measurement light source 31, the target light source 51, the light source unit 61, the optical scanner 66, the detection unit 76, and the like shown in FIG. To control. Although not shown, the main control unit 110 controls the attenuator and polarization controller described above.

  The main control unit 110 performs movement control of the optical element. For example, the main control unit 110 moves the measurement light source 31, the collimating lens 32, and the ring translucent plate 33 in the optical axis direction by controlling the measurement driving unit 30A. The main control unit 110 moves the moving lens 41 in the optical axis direction by controlling the lens driving unit 41A. Further, the main control unit 110 controls the target driving unit 50A to move the target light source 51 and the target plate 52 in the optical axis direction. The main control unit 110 moves the focusing lens 67 in the optical axis direction by controlling the focusing driving unit 67A. The main control unit 110 controls the reference driving unit 70A to move the lens 73 and the reference mirror 74 in the optical axis direction. Each of these driving units includes, for example, an actuator such as a pulse motor, and a transmission mechanism that transmits the driving force generated by this actuator to the optical element.

  Although illustration is omitted, the adjustment function evaluation apparatus 1 may include a mechanism (optical system driving unit) for moving the optical system. The optical system driving unit includes, for example, a mechanism for moving the optical system three-dimensionally (that is, up and down direction, left and right direction, and front and rear direction) and a mechanism for rotating the optical system. The main control unit 110 controls the movement of the optical system by controlling the optical system driving unit.

  The main control unit 110 performs a process of writing data to the storage unit 120 and a process of reading data from the storage unit 120.

(Storage unit 120)
The storage unit 120 stores various data. The data stored in the storage unit 120 includes, for example, image data of an anterior segment image, data acquired by OCT (reflection intensity profile, image data, etc.), measurement data of an eye to be examined, and eye information to be examined. The eye information includes information about the subject such as patient ID and name, and information about the eye such as left / right eye identification information.

  In one embodiment, the storage unit 120 stores reference data related to the crystalline lens. The reference data may include information indicating a reference position of a part of the lens. Further, the reference data may include information indicating a reference shape of a part of the crystalline lens. The portion of the lens may include, for example, at least a portion of the front surface and / or at least a portion of the back surface of the lens.

  The reference position indicates, for example, the position of the lens in a state where a predetermined adjustment stimulus (reference adjustment stimulus) is applied. The reference adjustment stimulus can be arbitrarily set. For example, an adjustment stimulus corresponding to the far point is used as the reference adjustment stimulus. The reference position may be any form of information. In one example, the reference position is a portion corresponding to the above-mentioned part such as a front surface or a rear surface with respect to a predetermined position (for example, an upper end position, a lower end position, or a center position in the z direction) of the frame of the OCT image ) Relative position. In another example, the reference position is a relative position of the target portion of the crystalline lens with respect to a predetermined image position in the OCT image (for example, a corneal vertex position, a pupil center position, or a lens center position). Alternatively, the reference position can be obtained as a data position (for example, a coordinate value in the depth direction and / or a coordinate value in the scan direction) in the reflection intensity profile.

  The reference shape indicates, for example, the shape of the lens in a state where the reference adjustment stimulus is applied. The reference shape may be any form of information. In one example, the reference shape is information indicating the shape of the target portion of the crystalline lens in the OCT image. This shape information may be information representing the shape of the target part as it is or information representing the approximate shape thereof. The shape information may be expressed by an image or a pixel arrangement, or may be expressed mathematically using a graph or a mathematical expression. Examples of mathematical expressions include curvature, radius of curvature, tangential direction (differential value, slope), and normal direction.

  The reference data may be provided for each subject, or may be provided as standard data (general data, statistical data). When it is provided for each subject, a test for the subject (for example, the left and right eye) is performed in advance. In this preliminary examination, for example, OCT is performed on the eye to be examined in a state where the reference adjustment stimulus is presented. Or when the test | inspection which can be used as reference | standard data was implemented in the past, it is possible to use the result of this test | inspection as reference | standard data.

  On the other hand, when standard data is provided, standard data is generated by statistically processing a plurality of data acquired by examination of a plurality of eyes. This statistical process includes, for example, an average calculation process. A plurality of standard data can be provided. For example, a plurality of standard data can be generated according to predetermined attributes such as sex, age, disease name, and eyeball characteristic values. The main control unit 110 receives an input of the attribute of the eye to be examined and selects standard data corresponding to this attribute. At this time, single standard data can be selected, or two or more standard data can be selected. In the latter case, new standard data can be created by combining two or more standard data. Alternatively, standard data for each combination of a plurality of attributes may be created in advance.

(Image forming unit 150)
The detector 76 detects the interference light obtained by superimposing the return light of the measurement light and the reference light, and outputs a signal. This signal is input to the image forming unit 150. The image forming unit 150 obtains the reflection intensity profile of the A line at the measurement light irradiation position (scanning point) based on the signal from the detection unit 76. Further, the image forming unit 150 processes the reflection intensity profile of each A line to form image data of an A line image (A scan image). In addition, the image forming unit 150 arranges a plurality of A scan images according to the scan pattern of the measurement light (arrangement of scan points), so that the A scan image is one-dimensionally (linearly or curvedly). Image data of an arrayed two-dimensional cross-sectional image (B-scan image) and image data (stack data) of a three-dimensional cross-sectional image in which A-scan images are two-dimensionally arrayed are formed.

  Such image forming processing includes noise removal (noise reduction), filter processing, FFT (Fast Fourier Transform), and the like, as in the past. The image forming unit 150 includes, for example, a hardware circuit and a processor that executes image forming software. In this specification, “image data” and “image” may be identified with each other.

(Data processing unit 160)
The data processing unit 160 executes various data processing. For example, the data processing unit 160 performs various types of image processing and analysis processing on the OCT image and the anterior segment image. Examples include luminance correction and dispersion correction. In addition, the data processing unit 160 forms volume data (voxel data) by performing interpolation processing or the like on the stack data formed by the image forming unit 150. In addition, the data processing unit 160 generates display data by rendering the stack data and volume data. The data processing unit 160 includes a hardware circuit and a processor that executes data processing software.

  The data processing unit 160 is an example of an “analysis unit”. That is, the data processing unit 160 generates evaluation information related to the adjustment function of the eye E by analyzing data acquired by OCT for the eye E to which the adjustment stimulus is applied. For this purpose, the data processing unit 160 is provided with a lens information generation unit 161, an evaluation information generation unit 162, and an optical characteristic information acquisition unit 163.

  Here, the inspection executed in this embodiment will be described. First, a regulatory stimulus is applied to the eye E. In this embodiment, an adjustment stimulus is applied by the target projection optical system 50. More specifically, the adjustment function evaluation apparatus 1 guides the focus of the eye E to an arbitrary position by moving the target light source 51 and the target plate 52 by the target driving unit 50A. Thereby, an arbitrary adjusting force is induced.

  Next, the adjustment function evaluation apparatus 1 performs OCT on the eye E in a state where the adjustment stimulus is applied. In this process, one or more regulatory stimuli are applied to the eye E. When a single regulatory stimulus is applied, OCT is performed in a state where the regulatory stimulus is applied, and the adjustment is performed based on the data acquired thereby and the reference data stored in the storage unit 120. Functional evaluation is performed. On the other hand, when two or more adjustment stimuli corresponding to different focal positions are applied, the OCT is executed in a state where each adjustment stimulus is applied while sequentially switching and applying these adjustment stimuli. Thereby, data corresponding to each regulatory stimulus is acquired. Then, the evaluation of the regulatory stimulus is executed based on the acquired two or more data. At this time, the evaluation may be performed in consideration of the reference data.

  The data processing unit 160 executes the processing shown below to acquire information (change information) indicating a change in the crystalline lens accompanying a change in the regulatory stimulus, and generates evaluation information based on the change information.

(Crystal lens generation unit 161)
The lens information generation unit 161 generates lens information indicating the position and / or shape of a region corresponding to a part of the lens based on data acquired by OCT with respect to the eye E to be examined in a state where a regulatory stimulus is applied. To do.

  The OCT data to be analyzed may be a signal from the detection unit 76 or arbitrary data obtained by processing the signal. For example, the OCT data is a reflection intensity profile or image data. Further, a part of the lens may include at least a part of the front surface and / or at least a part of the rear surface of the lens.

  The position of the region corresponding to a part of the crystalline lens may be set similarly to the case of the reference data. For example, the relative position of the target portion of the crystalline lens with respect to the predetermined position of the frame of the OCT image, or a predetermined image in the OCT image It may be the relative position of the target portion of the crystalline lens with respect to the position, the data position in the reflection intensity profile, or the like.

  Further, the shape of the region corresponding to a part of the crystalline lens may be set in the same manner as in the case of the reference data. For example, it may be information indicating the shape of the target part as it is or information indicating the approximate shape thereof. It may be expressed by an image or a pixel arrangement, or may be expressed mathematically using a graph or a mathematical expression.

  An example of processing executed when the OCT data is a reflection intensity profile will be described. As an example, it is assumed that the OCT data is a reflection profile P shown in FIG. 4A. The lens information generation unit 161 includes the characteristic value (maximum value, minimum value, maximum value, minimum value, etc.) of the reflection profile P, the shape of the reflection profile P, anatomical data of eyes, and clinical data (for example, tissue and The depth position of the predetermined part of the eye E is specified based on the depth position (general or individual relationship with the z-coordinate value).

For example, the crystalline lens information generation unit 161 identifies z ₀ that is the minimum z coordinate value with a non-zero reflected light amount L, and determines this as the position of the corneal surface (frontal cornea) at the measurement position (A line). To do. Alternatively, lens information generating unit 161, the reflected light amount L is to identify the z ₀ is the z coordinate value takes the maximum value, determines which the position of the corneal surface in the A-line. Alternatively, the crystalline lens information generation unit 161 specifies z ₀ that is the z coordinate value of the first peak from the shallow side (−z side) to the deep side (+ z side), and uses this as the cornea in the A line. Judged as the position of the surface. Similarly, the crystalline lens information generation unit 161 identifies z ₁ , z ₂ , and z ₃ that are the z coordinate values of the second, third, and fourth peaks, and the position of the corneal posterior surface in the A line, respectively. The position of the front surface of the lens and the position of the rear surface of the lens are determined.

  Note that it is possible to discriminate between the case where the measurement light passes through the pupil and the case where the measurement light enters the iris, and the processing can be switched according to the discrimination result. This discrimination process is executed based on, for example, the position of the scanning point (A line) in the scan pattern and the position of the pupil (or iris) specified by analyzing the anterior segment image obtained by the imaging optical system 10. Is done. The example shown in FIG. 4A corresponds to the case where the measurement light passes through the pupil, and the peak corresponding to the iris is not detected. On the other hand, although illustration is omitted, when the measurement light is incident on the iris, the first and second peaks similarly correspond to the front and back surfaces of the cornea, and the third peak corresponds to the iris front. When a light source having a relatively high depth is used, for example, the rear surface of the iris is detected as the fourth peak, the front surface of the lens is detected as the fifth peak, and the rear surface of the lens is detected as the sixth peak. .

An example of processing executed when the OCT data is image data will be described. As an example, it is assumed that the OCT data is an image G shown in FIG. 4B. The image G is formed by a plurality of A scan data (A scan images) arranged in the x direction. Each A scan data is image data obtained by assigning a luminance value to the light amount value of the reflection profile. The A scan data A _k arranged at the x coordinate value x _k in the image G corresponds to the reflection profile P in FIG. 4A. Reference numeral H ₀ is an image area corresponding to the anterior surface of the cornea, reference numeral H ₁ is an image area corresponding to the posterior surface of the cornea, reference numeral H ₂ is an image area corresponding to the anterior surface of the lens, and reference numeral H ₃ corresponds to the posterior surface of the lens. This is an image area to be processed.

The lens information generation unit 161 determines the depth position of the predetermined part of the eye E based on the pixel value (luminance value) of the image G, the form of the object being drawn (such as the size, shape, and position of the tissue). Is identified. For example, the crystalline lens information generation unit 161 specifies an image region H ₀ corresponding to the front surface of the cornea by executing a segmentation process known in the OCT field, and specifies its depth position. The depth position of the image region H ₀ is one or more values of the plurality of positions corresponding to a plurality of pixels constituting the image region H ₀ (e.g. maximum, minimum, maximum value, minimum value, etc.) but Alternatively, it may be one or more values (for example, statistical values such as an average value, a median value, and a mode value) obtained by performing arithmetic processing on the plurality of positions.

  In addition, an image region corresponding to a predetermined part (cornea, crystalline lens, or a boundary between them) is specified. When this processing is automatically performed, the lens information generation unit 161 determines an image region of a predetermined part and an image region other than that based on the feature or pixel value (luminance value) of the OCT data. This processing includes, for example, threshold processing and pattern matching.

  Note that part of the processing can also be performed manually. In that case, the main control unit 110 causes the display unit 181 to display a cross-sectional image. The user observes the displayed cross-sectional image, recognizes an image area corresponding to a predetermined tissue, and designates it using the operation unit 182. As an example of the designation method, a plurality of points are input on the outline of an image region corresponding to a predetermined tissue using a pointing device such as a mouse. The crystalline lens information generation unit 161 obtains a curve connecting a plurality of input points. This curve is an approximate curve such as a spline curve or a Bezier curve. The area delimited by these curves is the target image area. As another designation method, a contour can be input using a pointing device.

The crystalline lens information generation unit 161 can generate crystalline lens information from the information obtained by the above processing. For example, the crystalline lens information generation unit 161 executes the processing shown in FIG. 4A for each A line data, whereby the front surface position (z ₂ ) and the rear surface position (z) of the crystalline lens for each A line position (scanning point position). ₃ ) can be acquired and lens information including them can be generated. In addition, the lens information generation unit 161 acquires information indicating the shape of the front surface and the rear surface of the lens based on the front surface position and the rear surface position of the plurality of lenses related to the plurality of A lines, and generates lens information including the information. can do.

Alternatively, the lens information generation unit 161 executes the processing shown in FIG. 4B for each B scan data (B scan image), thereby determining the position of the lens front image H _{2 and} the position of the lens rear image H _{3 in} the B cross section. It is possible to acquire and generate lens information including it. Further, the lens information generating unit 161, by analyzing the lens front image H ₂ and retrolental face image H _3, it is possible to acquire the information indicating the shape, to produce the lens information including the same. In addition, the lens information generation unit 161 acquires two-dimensional or three-dimensional position information and shape information of the front surface and the rear surface of the lens based on B scan data regarding a plurality of B cross sections, and stores lens information including the information. Can be generated.

(Evaluation information generation unit 162)
The evaluation information generation unit 162 generates evaluation information related to the adjustment function of the eye E based on the lens information generated by the lens information generation unit 161. In order to execute this process, the evaluation information generation unit 162 includes a change information acquisition unit 1621 and an information generation unit 1622.

  As described above, the crystalline lens information includes positional information and / or shape information of the crystalline lens in a state where the regulatory stimulus is applied. The position information of the crystalline lens indicates the position of the front surface and the rear surface of the crystalline lens, and the shape information indicates the shape of the front surface and the rear surface of the crystalline lens. When the regulatory stimulus is applied, the thickness of the lens changes, thereby changing the position and shape of the front surface and the position and shape of the rear surface.

  When OCT is performed on the eye E in a state where each of two or more regulatory stimuli is applied, two or more pieces of lens information corresponding to the two or more regulatory stimuli are generated. The change information acquisition unit 1621 acquires change information indicating changes in the crystalline lens accompanying changes in the regulatory stimulus based on the two or more pieces of generated lens information. An example of this processing will be described below.

  It is assumed that first lens information corresponding to the first regulatory stimulus and second lens information corresponding to the second regulatory stimulus are obtained. Each of the first and second lens information includes position information on the front surface and position information on the rear surface of the lens.

The change information acquisition unit 1621 calculates the difference between the position of the front surface and the position of the rear surface shown in the first crystalline lens information. This process corresponds to, for example, a process of calculating the difference z ₃ −z ₂ between the _two z coordinate values z ₂ and z ₃ in FIGS. 4A and 4B. Thereby, the thickness of the crystalline lens in the A line is obtained. This process may be executed for the entire acquired OCT data (that is, for all A lines) or only for representative positions (for example, the corneal apex, the pupil center, or the lens center). When the process is executed for two or more positions, a lens thickness distribution is obtained.

By executing such processing for each of the first and second lens information, lens thickness information (first thickness information) in a state where the first regulatory stimulus is applied, Lens thickness information (second thickness information) in a state where the second regulatory stimulus is applied is obtained. The change information acquisition unit 1621 calculates a difference ΔT = | T ₁ −T ₂ | between the thickness T ₁ indicated by the _first thickness information and the thickness T ₂ indicated by the second thickness information. Here, the absolute value is a convenience for making the calculation result a non-negative value. ΔT represents the amount of change in the lens thickness accompanying the change in the regulatory stimulus. This thickness change amount ΔT is an example of change information.

  When the lens thickness is obtained for two or more positions, the first OCT data obtained in the state where the first regulatory stimulus is applied and the state where the second regulatory stimulus is applied. The difference ΔT is calculated for each A line corresponding to the obtained second OCT data. The association of the A line is performed based on the anterior segment image acquired by the imaging optical system 10, the first and second OCT data, and the like. By such processing, a distribution of changes in lens thickness associated with changes in the regulatory stimulus is obtained. This distribution of changes in thickness is an example of change information.

  The change information acquired based on the position information of the crystalline lens is not limited to the change in thickness, and may be arbitrary information obtained from the position information. Further, when the shape information of the crystalline lens is used, by performing the same process as described above, the curvature and inclination change at a predetermined part (for example, the front vertex position) of the crystalline lens, or a predetermined range (for example, a partial region of the front surface). The distribution of the curvature and inclination change in the can be obtained.

  The information generation unit 1622 generates evaluation information based on the change information acquired by the change information acquisition unit 1621. The change information includes parameters such as the above-described change amount and change distribution. For example, the information generation unit 1622 generates evaluation information by referring to correspondence information in which a parameter value is associated with a degree of adjustment function. The correspondence information is stored in the storage unit 120 in advance. Corresponding information is created, for example, by conducting tests including the application of regulatory stimuli and OCT on a large number of eyes (including normal eyes and / or diseased eyes) and statistically processing the clinical data obtained thereby. Is done. A plurality of pieces of correspondence information corresponding to predetermined attributes such as sex, age, disease name, eyeball characteristic value, etc. are provided, and these are selectively used according to the attributes of the subject or eye E May be.

Specific examples of the correspondence information include the following forms: the first range “0 ≦ ΔT ≦ ΔT ₁ ” of the thickness variation ΔT is associated with the degree of adjustment function “very low”; The second range of change “ΔT ₁ <ΔT ≦ ΔT ₂ ” is associated with the degree of adjustment function “low”; the third range of thickness change “ΔT ₂ <ΔT” and the adjustment function “Normal” is associated. The information generation unit 1622 determines which of the first to third ranges the thickness change amount ΔT included in the change information acquired by the change information acquisition unit 1621 and the evaluation result associated with the range ("Very low", "low" or "normal") is specified, and evaluation information including this evaluation result is generated.

  When the reference data related to the lens is stored in the storage unit 120, the change information acquisition unit 1621 adjusts the stimulating stimulus based on the OCT data obtained for the eye E to which the adjusting stimulus is applied and the reference data. Change information indicating a change in the crystalline lens associated with the application of is acquired. This process may be similar to the above. Furthermore, the information generation unit 1622 generates evaluation information based on the change information acquired by the change information acquisition unit 1621. This process may be the same as described above.

(Optical characteristic information acquisition unit 163)
The evaluation information may include information indicating the optical characteristics of the eye E. In that case, an optical characteristic information acquisition unit 163 is provided. The optical characteristic information acquisition unit 163 analyzes the optical characteristics of the eye to be examined acquired by the measurement optical system 30. The measurement optical system 30 measures the optical characteristics of the eye E under the condition where the adjustment stimulus is given. For example, the measurement optical system 30 acquires the first measurement value by measuring the eye to be examined in a state where the first accommodation stimulus is given, and the subject in the state where the second accommodation stimulus is given. The optometry is measured to obtain a second measurement value. These measurements are performed in parallel with OCT or at different times. The optical characteristic information acquisition unit 163 acquires information indicating a change in the optical characteristic of the eye to be examined accompanying a change in the accommodation stimulus based on the acquired first measurement value and second measurement value. This information is referred to as optical characteristic information.

  The measurement optical system 30 of this embodiment functions as a refractometer that measures the refractive power of the eye to be examined. The optical characteristic information acquisition unit 163 acquires optical characteristic information indicating a change in the adjustment amount of the eye to be examined due to a change in the accommodation stimulus based on the first measurement value and the second measurement value of the refractive power of the eye to be examined. . This process calculates the difference between the first measurement value and the second measurement value. Note that an actual adjustment amount per assumed unit adjustment amount may be obtained by dividing the difference between the two measurement values by the change amount of the adjustment stimulus (that is, the assumed adjustment amount). Further, the inspection may be performed a plurality of times to obtain statistical values such as average values and variations.

  Although the eye refractive power is measured in this embodiment, other optical characteristics of the eye to be examined may be measured. For example, the aberration of the eye to be examined can be measured. As an example of a configuration for performing aberration measurement, there is a wavefront sensor described in Japanese Patent Application Laid-Open No. 2001-275972 by the present applicant. A wavefront sensor irradiates the fundus of a subject's eye with a light beam from a point light source, and analyzes the distribution of multiple point images obtained by detecting the reflected light with an area sensor via a Hartmann plate, thereby aberrations of various orders. Is a device for obtaining According to such a wavefront sensor, it is possible to measure not only sphericalness and astigmatism but also higher-order aberrations. The optical characteristic information acquisition unit 163 acquires optical characteristic information indicating the change in the aberration of the eye to be inspected with the change in the accommodation stimulus based on the first measurement value and the second measurement value for each order of aberration.

  Further, when a light source with a high depth is used in OCT, the return light of the measurement light includes information in a relatively wide range in the depth direction (z direction). The optical characteristic information acquisition unit 163 can obtain the amount of aberration generated in the range within the eye E based on the OCT data.

(User interface 180)
The user interface 180 is a man-machine interface that is used for providing information to the examiner or the subject and for the examiner or the subject to perform operations or input information. The user interface 180 includes a display unit 181 and an operation unit 182.

(Display unit 181)
The display unit 181 includes, for example, a display device provided in the adjustment function evaluation apparatus 1. Further, when a computer is connected to the adjustment function evaluation apparatus 1, the display unit 181 may include a display of this computer. The display unit 181 displays information under the control of the main control unit 110.

(Operation unit 182)
The operation unit 182 is used for operation of the adjustment function evaluation apparatus 1 and information input. The operation unit 182 includes hardware keys such as levers and buttons provided in the adjustment function evaluation device 1. When a computer is connected to the adjustment function evaluation apparatus 1, the operation unit 182 may include an operation device or an input device of the computer. The main control unit 110 receives the signal from the operation unit 182 and executes control.

  The display unit 181 and the operation unit 182 do not need to be configured as individual devices. For example, a device in which a display function and an operation function are integrated can be used, such as a touch panel. In that case, a graphical user interface (GUI) displayed on the display unit 181 is used as the operation unit 182.

[Operation]
The operation of the adjustment function evaluation apparatus 1 will be described.

(First operation example)
A first operation example of the adjustment function evaluation apparatus 1 is shown in FIG. In this operation example, two adjustment stimuli are applied to the eye E.

(S1: Alignment)
First, alignment of the optical system with respect to the eye E is performed. Specifically, first, the main control unit 110 turns on the anterior segment illumination light source 11 and the alignment light source 21 and starts the operation of the image sensor 16. Thereby, an anterior ocular segment image of the eye E to which the alignment visual target image is projected is obtained. The main control unit 110 displays the anterior segment image on the display unit 181. The user aligns the eye E by adjusting the position of the optical system while referring to the position of the alignment target image reflected in the anterior segment image in the same manner as before. The main control unit 110 can automatically perform alignment by analyzing the position of the alignment target image and adjusting the position of the optical system.

(S2: Application of the first regulatory stimulus)
When the alignment is completed, the main control unit 110 applies the first adjustment stimulus to the eye E to be examined. Specifically, the main control unit 110 turns on the target light source 51 and controls the target drive unit 50A to place the target light source 51 and the target plate 52 at positions corresponding to the first adjustment stimulus. Let Note that the positions of the visual target light source 51 and the like corresponding to the first adjustment stimulus are set in advance. This is, for example, a position corresponding to the far point of the eye E.

(S3: OCT and optical property measurement)
In a state where the first adjustment stimulus is applied to the eye E, the main control unit 110 causes OCT and optical characteristic measurement to be performed. Note that these two operations may be performed in parallel or at different timings.

  OCT will be described. First, the main control unit 110 controls the reference driving unit 70A to move the reference mirror 74 and the lens 73 to a position where OCT data in a range including the target portion of the crystalline lens is obtained. This process is executed with reference to a live OCT image obtained by repetitive OCT, for example. When the positioning of the reference mirror 74 is completed, the main control unit 110 controls the light source unit 61 and the optical scanner 66 to execute OCT of the region of the eye E including the target part. The detection unit 76 detects interference light between the measurement light passing through the eye E and the return light of the reference light from the reference mirror 74. The image forming unit 150 forms OCT data (reflection intensity profile or image data) based on the signal output from the detection unit 76. This OCT data includes information indicating the form (position, shape, etc.) of the lens in a state where the first regulatory stimulus is applied. The main control unit 110 causes the storage unit 120 to store the acquired OCT data (first OCT data).

  The optical characteristic measurement will be described. First, the main control unit 110 turns on the measurement light source 31. The measurement light beam output from the measurement light source 31 is reflected by the fundus of the eye E and is detected by the image sensor 16. The main control unit 110 sends the signal output from the image sensor 16 to the optical characteristic information acquisition unit 163. This signal includes information indicating the size and shape of the cross section of the measurement light beam detected by the image sensor 16. The optical characteristic information acquisition unit 163 analyzes the signal to calculate the sphericity, astigmatism, astigmatism axis, and the like of the eye E. The main control unit 110 stores the calculated measurement value of the optical characteristic in the storage unit 120. This measured value indicates the optical characteristic value of the eye E in a state where the first adjustment stimulus is applied, and is used as the first measured value.

(S4: Application of the second regulatory stimulus)
When the OCT and the optical characteristic measurement are completed, the main control unit 110 applies the second accommodation stimulus to the eye E to be examined. Specifically, the main control unit 110 controls the target driving unit 50A so that the target light source 51 and target target plate 52 disposed at the position corresponding to the first adjustment stimulus are changed to the second target stimulus. Move to a position corresponding to the regulatory stimulus. Note that the positions of the target light source 51 and the like corresponding to the second adjustment stimulus are set in advance. This is, for example, a position corresponding to the near point of the eye E.

(S5: OCT and optical property measurement)
In a state where the second adjustment stimulus is applied to the eye E, the main control unit 110 causes OCT and optical characteristic measurement to be performed. This process is executed in the same manner as in step S3. Thereby, second OCT data for the eye E to be examined in a state where the second regulatory stimulus is applied, and a second measured value of the optical characteristics of the eye E are obtained. These pieces of information are stored in the storage unit 120.

(S6: Generation of evaluation information)
The data processing unit 160 generates two lens information based on the first and second OCT data acquired in step S3 and step S5, and changes the lens according to the change in the regulatory stimulus based on the lens information. The change information shown is acquired, and evaluation information is generated based on the acquired change information.

  In addition, the data processing unit 160 generates information (optical characteristic change information) indicating a change in optical characteristics accompanying a change in the regulatory stimulus based on the first and second measurement values acquired in steps S3 and S5. To do. This process includes, for example, a process for obtaining a difference between the first measurement value and the second measurement value. The acquired optical characteristic change information is included in the evaluation information.

  The main control unit 110 stores the generated evaluation information in the storage unit 120 and causes the display unit 181 to display the evaluation information. Thus, the process according to this operation example ends.

(Second operation example)
A second operation example of the adjustment function evaluation apparatus 1 is shown in FIG. In this operation example, a single adjustment stimulus is applied to the eye E, and evaluation information is generated with reference to the reference data. It is assumed that the reference data includes information indicating the thickness of the crystalline lens in a state where the adjustment stimulus corresponding to the far point is applied. This information is information obtained in the past for the eye E or standard information. Further, the reference data may include a measured value of the optical characteristics of the eye E in a state where the regulatory stimulus is applied.

(S11: Alignment)
Similar to the first operation example, alignment of the optical system with respect to the eye E is performed.

(S12: Giving regulatory stimulus)
When the alignment is completed, the main control unit 110 applies an adjustment stimulus corresponding to the near point of the eye E to the eye E. If the reference data includes information indicating the thickness of the crystalline lens corresponding to the near point, an adjustment stimulus corresponding to the far point of the eye E is applied to the eye E.

(S13: OCT and optical property measurement)
In a state where the adjustment stimulus is applied to the eye E, the main control unit 110 causes OCT and optical property measurement to be executed. This process is executed in the same manner as in the first operation example.

(S14: Reading of reference data)
The main control unit 110 reads the reference data stored in the storage unit 120 and sends it to the data processing unit 160.

(S15: Generation of evaluation information)
The data processing unit 160 obtains lens information (thickness information) based on the OCT data acquired in step S13, and obtains the obtained thickness information and reference data read out in step S14 (similarly, the lens thickness). Change information indicating a change in the lens accompanying a change in the regulatory stimulus is acquired, and evaluation information is generated based on the acquired change information.

  Further, the data processing unit 160 obtains optical characteristic change information based on the measured value of the optical characteristic acquired in step S13 and the measured value included in the reference data. The optical characteristic change information is included in the evaluation information.

  The main control unit 110 stores the generated evaluation information in the storage unit 120 and causes the display unit 181 to display the evaluation information. Thus, the process according to this operation example ends.

[Action / Effect]
The operation and effect of the adjustment function evaluation apparatus according to the embodiment will be described.

  The adjustment function evaluation apparatus according to the embodiment includes an adjustment stimulus applying unit, a measurement unit, and an analysis unit. The adjustment stimulus applying unit has a function of applying an adjustment stimulus to the eye to be examined. In this embodiment, the target projection optical system 50 corresponds to an adjustment stimulus applying unit, and visual information (target) is used as the adjustment stimulus. A measurement part performs OCT with respect to the object site | part in the eye to be examined including at least one part of a crystalline lens. In this embodiment, the interference optical system 60 (and the image forming unit 150) corresponds to a measurement unit. An analysis part produces | generates the evaluation information regarding the adjustment function of a to-be-tested eye by analyzing the data acquired by OCT with respect to the to-be-examined eye in the state where the adjustment stimulus is given. In this embodiment, the data processing unit 160 corresponds to an analysis unit, and evaluation information is generated by analyzing a reflection intensity profile and image data acquired by OCT.

  In the embodiment, the analysis unit may include a lens information generation unit and an evaluation information generation unit. The crystalline lens information generating unit generates crystalline lens information indicating the position and / or shape of a region corresponding to a part of the crystalline lens based on data acquired by OCT for the eye to be examined in a state where the regulatory stimulus is applied. The region corresponding to a part of the lens includes, for example, a front surface region corresponding to at least a part of the front surface of the lens and / or a rear surface region corresponding to at least a part of the rear surface of the lens. The evaluation information generation unit generates evaluation information based on the lens information generated by the lens information generation unit.

  According to such an embodiment, it is possible to detect the state of change of the lens shape with respect to the regulatory stimulus with high accuracy using OCT. Therefore, it is possible to evaluate the adjustment function of the eye to be examined in detail.

  In the embodiment, the regulation stimulus applying unit may be configured to be capable of selectively giving two or more regulation stimuli. In this case, the measurement unit may acquire two or more data by performing OCT on the eye to be examined in a state where each of the two or more regulatory stimuli is applied. The crystalline lens information generation unit may generate two or more crystalline lens information based on the two or more data acquired by the measurement unit. The evaluation information generation unit acquires change information indicating a change in the lens accompanying a change in the regulatory stimulus based on the two or more generated lens information, and further generates evaluation information based on the acquired change information. It may be configured to do.

  According to such an embodiment, an actual change in the shape of the crystalline lens can be detected by OCT by performing an examination while actually changing the regulatory stimulus. Therefore, it is possible to improve the accuracy and accuracy of the evaluation of the adjustment function.

  In the embodiment, the adjustment function can be evaluated using predetermined reference data. The reference data is data indicating a reference position and / or a reference shape of a part of the lens, and is stored in advance in the storage unit. The storage means may be provided in the adjustment function evaluation apparatus or may be provided outside the storage function evaluation apparatus. As an example of the latter, the storage means may be a server (such as an electronic medical record system) on a LAN in a medical institution. The evaluation information generation unit acquires change information indicating a change in the lens accompanying the application of the regulatory stimulus based on the reference data acquired from the storage unit and the lens information generated by the lens information generation unit, The evaluation information may be generated based on the acquired change information.

  According to such an embodiment, there is a possibility that the accuracy and accuracy may be lower than in the case where the examination is performed by actually changing the regulation stimulus, but the regulation function can be easily evaluated by applying a single regulation stimulus. It can be carried out.

  In the embodiment, the measurement unit may include a measurement optical system that measures the optical characteristics of the eye to be examined in a state where the adjustment stimulus is applied. Thereby, the optical characteristic of the eye to be examined in a state where the adjustment stimulus is given can be acquired. Furthermore, it is also possible to acquire a change in the optical characteristics of the eye to be examined accompanying a change in the regulatory stimulus. Therefore, it is possible to perform a composite evaluation using both the change in the shape of the crystalline lens and the change in the optical characteristics of the eye to be examined.

<Second Embodiment>
An embodiment using iterative OCT measurement will be described. The repetitive OCT measurement means a measurement technique for repeatedly executing OCT on substantially the same site of the eye to be examined. According to repetitive OCT measurement, OCT data of substantially the same part of the eye to be examined is repeatedly acquired. In addition, by repeating OCT at a predetermined repetition rate and repeatedly acquiring OCT image data, time-series images of substantially the same part of the eye to be examined can be obtained. Furthermore, a moving image can be obtained by applying a relatively fast repetition rate.

  The adjustment function evaluation apparatus according to this embodiment has the same configuration as that of the first embodiment, for example. Hereinafter, reference is made to the drawings in the first embodiment.

(First operation example)
In this operation example, OCT is performed on the eye E in a state in which a certain adjustment stimulus is applied. In addition, the relationship between the timing which gives a regulation stimulus and the timing which performs OCT may be arbitrary. For example, the period during which the constant regulatory stimulus is applied may be a part or all of the period during which OCT is performed. Hereinafter, reference will be made to FIG.

(S21: Alignment)
Similar to the first embodiment, alignment of the optical system with respect to the eye E is performed.

(S22: Start of OCT)
When the alignment is completed, the main control unit 110 starts OCT.

(S23: Giving regulatory stimulus)
After the OCT is started, the main control unit 110 applies a predetermined adjustment stimulus to the eye E. This processing may be performed, for example, by directly applying a predetermined regulatory stimulus from a state where no regulatory stimulus is applied, or by gradually shifting from a state where no regulatory stimulus is applied to a predetermined regulatory stimulus. May be.

(S24: End of OCT)
In response to a predetermined trigger, the main control unit 110 ends OCT. Examples of the trigger include an instruction from the user, elapse of a predetermined time, occurrence of a predetermined event, and the like. The predetermined event is, for example, a change in the state of the eye E or a substantial steady state.

(S25: Generation of evaluation information)
The data processing unit 160 generates evaluation information based on the OCT data acquired during steps S22 to S24.

  The evaluation information in this operation example indicates a time-series change in the lens shape (that is, a time-series change in the adjustment force) accompanying the application of a predetermined adjustment stimulus. More specifically, this evaluation information includes, for example, a time-series change in the shape of the lens when a predetermined regulatory stimulus is given, or a period of time after the lens is given before the predetermined regulatory stimulus is given. Shows time-series changes in shape, time-series changes in lens shape during the period from when a prescribed regulatory stimulus is applied until the lens shape stabilizes, and fluctuations in the lens shape after the lens shape stabilizes .

  An example of processing for acquiring such evaluation information will be described. In this operation example, a plurality of OCT data arranged in time series are obtained. The data processing unit 160 performs the same processing as that of the first embodiment on each OCT data. For example, the data processing unit 160 obtains lens thickness information in each time phase based on each OCT data. Thereby, a data set showing a time-series change of the lens thickness is obtained. Further, the data processing unit 160 obtains parameters such as the amount of change in thickness, the rate of change in thickness, the amount of fluctuation in thickness change, and the frequency based on this data set. Then, the data processing unit 160 generates evaluation information by referring to correspondence information in which a parameter value is associated with a degree of adjustment function, for example. The correspondence information may be information in the same form as in the first embodiment.

  The main control unit 110 stores the generated evaluation information in the storage unit 120 and causes the display unit 181 to display the evaluation information. Thus, the process according to this operation example ends.

(Second operation example)
In this operation example, the regulatory stimulus is changed while executing OCT. Note that, as in the first operation example, the relationship between the timing of applying the regulatory stimulus and the timing of executing the OCT may be arbitrary. Further, the change in the regulatory stimulus may be a continuous change or a stepwise change. Hereinafter, reference will be made to FIG.

(S31: Alignment)
Similar to the first embodiment, alignment of the optical system with respect to the eye E is performed.

(S32: Start of OCT)
When the alignment is completed, the main control unit 110 starts OCT.

(S33: Start of application of regulatory stimulus)
After the OCT is started, the main control unit 110 applies a predetermined initial adjustment stimulus to the eye E. This process is executed, for example, in the same manner as in the first operation example.

(S34: Change in regulatory stimulus)
The main control unit 110 changes the adjustment stimulus given to the eye E. The change of the regulation stimulus is automatically performed according to a preset process, for example. Alternatively, the adjustment stimulus is changed in accordance with the examiner's instruction.

  As another example, the change of the adjustment stimulus is executed according to the state of the adjustment force of the eye E. This process is executed, for example, by analyzing OCT data acquired sequentially in real time. More specifically, the data processing unit 160 is based on the time-series change of the peak position in the sequentially acquired reflection intensity profile, or the target portion (for example, the front surface or the rear surface of the lens) in the sequentially acquired image data. ) To obtain a time-series change in the form (position or shape) of the crystalline lens. The main control unit 110 changes the adjustment stimulus according to a predetermined algorithm based on a time-series change (change amount, change speed, degree of stability, etc.) of the lens form.

(S35: End of application of regulatory stimulus, end of OCT)
In response to a predetermined trigger, the main control unit 110 performs a process for terminating the application of the regulatory stimulus and a process for terminating the OCT. This trigger may be the same as in the first operation example, for example. Further, the end timing of the application of the regulatory stimulus and the end timing of the OCT may be the same or different. In the latter case, each end trigger is input.

(S36: Generation of evaluation information)
The data processing unit 160 generates evaluation information based on the OCT data acquired during steps S32 to S35. This process may be the same as in the first operation example.

  The main control unit 110 stores the generated evaluation information in the storage unit 120 and causes the display unit 181 to display the evaluation information. Thus, the process according to this operation example ends.

[Action / Effect]
The operation and effect of the adjustment function evaluation apparatus according to the embodiment will be described.

  The adjustment function evaluation apparatus according to the embodiment includes an adjustment stimulus applying unit, a measurement unit, and an analysis unit. The adjustment stimulus applying unit has a function of applying an adjustment stimulus to the eye to be examined. In this embodiment, the target projection optical system 50 corresponds to an adjustment stimulus applying unit, and visual information (target) is used as the adjustment stimulus. A measurement part performs OCT with respect to the object site | part in the eye to be examined including at least one part of a crystalline lens. In this embodiment, the interference optical system 60 (and the image forming unit 150) corresponds to a measurement unit. An analysis part produces | generates the evaluation information regarding the adjustment function of a to-be-tested eye by analyzing the data acquired by OCT with respect to the to-be-examined eye in the state where the adjustment stimulus is given. In this embodiment, the data processing unit 160 corresponds to an analysis unit, and evaluation information is generated by analyzing a reflection intensity profile and image data acquired by OCT.

  In the embodiment, the analysis unit may include a lens information generation unit and an evaluation information generation unit. The crystalline lens information generating unit generates crystalline lens information indicating the position and / or shape of a region corresponding to a part of the crystalline lens based on data acquired by OCT for the eye to be examined in a state where the regulatory stimulus is applied. The region corresponding to a part of the lens includes, for example, a front surface region corresponding to at least a part of the front surface of the lens and / or a rear surface region corresponding to at least a part of the rear surface of the lens. The evaluation information generation unit generates evaluation information based on the lens information generated by the lens information generation unit.

  According to such an embodiment, it is possible to detect the state of change of the lens shape with respect to the regulatory stimulus with high accuracy using OCT. Therefore, it is possible to evaluate the adjustment function of the eye to be examined in detail.

  In the embodiment, the measurement unit can repeatedly execute OCT for the target region of the eye to be examined. In this case, the lens information generating unit can generate a plurality of lens information based on a plurality of data acquired by repetitive OCT. Furthermore, the evaluation information generation unit can generate evaluation information based on the plurality of generated lens information.

  According to such an embodiment, it is possible to obtain a time-series change in the form of the lens based on a time-series change in data acquired by repetitive OCT, and evaluation information can be obtained based on the time-series change in the lens. Can be generated. As a result, it is possible to provide a novel evaluation method based on time-series changes in the adjustment function of the eye to be examined.

  In the embodiment, the measurement unit may be configured to perform repetitive OCT with respect to the eye to be examined in a state where a constant adjustment stimulus is applied.

  According to such an embodiment, it is possible to acquire a time-series change in the adjustment function of the eye to be examined in a state where a constant adjustment stimulus is applied. Further, it is possible to acquire a time-series change in the adjustment force induced by applying a certain adjustment stimulus. And it becomes possible to provide the novel evaluation method based on such information.

  In the embodiment, the adjustment stimulus applying unit may be configured to change the adjustment stimulus applied to the eye to be examined during at least a part of a period in which repetitive OCT is performed.

  According to such an embodiment, it is possible to acquire a time-series change in the adjustment force induced by the change in the applied adjustment stimulus. And it becomes possible to provide the novel evaluation method based on such information.

  In the embodiment, the measurement unit may include a measurement optical system that measures the optical characteristics of the eye to be examined in a state where the adjustment stimulus is applied. The measurement of optical characteristics may be performed once or twice or more. For example, it is possible to acquire a time-series change in optical characteristics by executing measurement of optical characteristics at a predetermined repetition rate.

  According to such an embodiment, it is possible to acquire the optical characteristics of the eye to be examined in a state where the adjustment stimulus is applied. Furthermore, it is also possible to acquire a change in the optical characteristics of the eye to be examined accompanying a change in the regulatory stimulus. Therefore, it is possible to perform a composite evaluation using both the change in the shape of the crystalline lens and the change in the optical characteristics of the eye to be examined.

[Modification]
The configuration described above is merely an example for carrying out the present invention. Therefore, arbitrary modifications (omitted, replacement, addition, etc.) within the scope of the present invention can be made as appropriate. The following modifications are included in the scope of the gist of the present invention.

  In the above-described embodiment, a configuration is used in which the adjustment stimulus is applied to the eye to be examined using the visual target. However, the method for applying the stimulus to the eye to be examined and the content of the stimulus are not limited thereto. For example, electrical stimulation, ultrasonic stimulation, or light stimulation can be applied to the eye to be examined. The electrical stimulation is applied, for example, by bringing an electrode into contact with a stimulation site (such as ciliary muscle) or the vicinity thereof. For example, the ultrasonic stimulation is applied by irradiating the stimulation site with ultrasonic waves using an ultrasonic transducer. The light stimulus is applied using a light source.

  The part of the eye to be examined to which the stimulus is applied is not limited to the part relating to the regulatory function (the lens, the chin band, the ciliary body). For example, a stimulus can be applied to the retina.

DESCRIPTION OF SYMBOLS 1 Adjustment function evaluation apparatus 10 Imaging | photography optical system 30 Measurement optical system 30A Measurement drive part 50 Target projection optical system 50A Target drive part 60 Interference optical system 61 Light source unit 66 Optical scanner 70A Reference drive part 74 Reference mirror 76 Detection part 100 Control Unit 110 main control unit 120 storage unit 150 image forming unit 160 data processing unit 161 crystalline lens information generation unit 162 evaluation information generation unit 1621 change information acquisition unit 1622 information generation unit 163 optical characteristic information acquisition unit 180 user interface (UI)
181 Display unit 182 Operation unit E Eye to be examined

Claims (7)

An adjustment stimulus applying unit for applying an adjustment stimulus to the eye to be examined;
A measurement unit that performs optical coherence tomography on a target region in the eye to be examined including at least a part of the lens; and
Analyzing data acquired by the optical coherence tomography performed on the target region at least when the accommodation stimulus is applied to the eye to be examined, and generating evaluation information regarding the accommodation function of the eye to be examined With an analysis section and
The measurement unit repeatedly executes optical coherence tomography for the target region at a predetermined repetition rate,
The analysis unit obtains a time-series change of the crystalline form based on a time-series change of data acquired by optical coherence tomography repeatedly executed at the predetermined repetition rate, and based on the time-series change of the form The evaluation function is generated. The adjustment function evaluation apparatus characterized by the above-mentioned. The adjustment function evaluation apparatus according to claim 1, wherein the analysis unit generates the evaluation information based on a time-series change in the form during a period in which the adjustment stimulus is given to the eye to be examined. The adjustment function evaluation apparatus according to claim 2, wherein the analysis unit obtains at least one of a time-series change of the lens thickness and a time-series change of the shape of the lens as the time-series change of the form. The adjustment function evaluation apparatus according to claim 2 or 3, wherein the analysis unit obtains at least one of a change amount and a change speed of the form as a time-series change of the form. The said analysis part produces | generates the said evaluation information based on the time-sequential change of the said form in the period after the form of the crystalline lens of the eye to be examined to which the said adjustment stimulus was given. Adjustment function evaluation device. The adjustment function evaluation apparatus according to claim 5, wherein the analysis unit obtains at least one of a time-series change of the lens thickness and a time-series change of the shape of the lens as the time-series change of the form. The adjustment function evaluation apparatus according to claim 5, wherein the analysis unit obtains a fluctuation frequency of the form as a time series change of the form.

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