JP7288110B2 - ophthalmic equipment - Google Patents

Description

The present invention relates to ophthalmic equipment.

2. Description of the Related Art In ophthalmology, an apparatus for obtaining an image of an eye to be examined (ophthalmic imaging apparatus) and an apparatus for measuring characteristics of an eye to be examined (ophthalmic measurement apparatus) are used.

Examples of ophthalmologic imaging equipment include optical coherence tomography (OCT) for obtaining data, a fundus camera for photographing the fundus, and a laser scanning system for obtaining a fundus image using a confocal optical system. There is a scanning laser ophthalmoscope (SLO) that obtains .

Examples of ophthalmologic measurement devices include an eye refraction tester (refractometer) that measures the refractive characteristics of an eye to be examined, a wavefront analyzer that obtains aberration data of the eye using a Hartmann-Shack sensor, and a corneal vertex and retinal fovea. There is an axial length measuring device that measures the distance (axial length) between the two.

The ophthalmologic apparatus exemplified above projects light toward the fundus of the subject's eye and obtains data based on the returned light. Therefore, when there is turbidity in the intermediate translucent body (lens, vitreous body, etc.), such as in a cataractous eye, the projected light and return light are affected by the turbidity, which may hinder suitable imaging and measurement.

A transillumination method is known as a method for grasping the turbidity of an intermediate translucent body. The transillumination method is a method of projecting illumination light onto the fundus of the eye and observing the illuminated pupil region from the inside of the subject's eye by its reflection. In the resulting retroillumination image, the turbidity portion appears as a shadow. When an error occurs in photography or measurement, the transillumination image is referred to and the alignment is adjusted so as to avoid opaque areas. .

JP 2013-146546 A

An object of the present invention is to specify a region suitable for imaging or measurement by projecting light onto the fundus.

An exemplary embodiment includes a data acquisition unit that projects light onto the fundus of an eye to be inspected and acquires data of the eye to be inspected based on the returned light, and an optical coherence tomography unit that acquires data of the eye to be inspected in a three-dimensional region of the anterior segment of the eye to be inspected. an OCT unit that applies an OCT scan to acquire OCT data; and a data processing unit that analyzes the OCT data and identifies a target region for projecting the light onto the fundus by the data acquisition unit. An ophthalmic device comprising:

According to an exemplary embodiment, it is possible to identify suitable regions for imaging or measuring by projecting light onto the fundus.

1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 4 is a flowchart representing an example of operations that can be performed by an ophthalmic device according to an exemplary embodiment; 4 is a flowchart representing an example of operations that can be performed by an ophthalmic device according to an exemplary embodiment; It is a schematic diagram showing an example of the configuration of an ophthalmologic apparatus according to a modification. FIG. 4 is a schematic diagram for explaining operations that can be performed by an ophthalmic device according to an exemplary embodiment; FIG. 4 is a schematic diagram for explaining operations that can be performed by an ophthalmic device according to an exemplary embodiment; FIG. 4 is a schematic diagram for explaining operations that can be performed by an ophthalmic device according to an exemplary embodiment; FIG. 4 is a schematic diagram for explaining operations that can be performed by an ophthalmic device according to an exemplary embodiment;

Exemplary aspects of ophthalmic devices according to embodiments will be described in detail with reference to the drawings. An ophthalmologic apparatus according to an embodiment is used to acquire data of an eye to be examined optically (that is, using light and optical technology). In particular, the ophthalmologic apparatus according to the embodiment can acquire data of the subject's eye by making light enter the eye through the pupil of the subject's eye.

Such an ophthalmic device includes, for example, at least one of an imaging function and a measurement function. Examples of ophthalmic devices with imaging functions include optical coherence tomography, fundus cameras, scanning laser ophthalmoscopes, and the like. Examples of ophthalmic devices with measurement functions include axial length measuring devices, eye refraction testing devices, wavefront analyzers, microperimeters, and perimeters.

In the following example, an ophthalmic imaging apparatus that combines swept-source OCT and a fundus camera is described, but embodiments are not limited thereto. The type of OCT is not limited to swept source OCT, and may be spectral domain OCT, for example.

The swept source OCT splits the light from the wavelength tunable light source into measurement light and reference light, superimposes the return light of the measurement light from the object on the reference light to generate interference light, and balances the interference light. In this method, an image is formed by performing Fourier transform or the like on detection data collected in response to wavelength sweeping and measurement light scanning by detecting with a photodetector such as a photodiode.

Spectral domain OCT divides light from a low coherence light source into measurement light and reference light, generates interference light by superimposing the return light of the measurement light from the object on the reference light, and generates the interference light spectrum In this method, the distribution is detected by a spectrometer, and the detected spectral distribution is subjected to Fourier transform or the like to form an image.

Thus, the swept-source OCT is an OCT technique that acquires a spectral distribution by time division, and the spectral domain OCT is an OCT technique that acquires a spectral distribution by space division. Note that the OCT techniques that can be used in the embodiments are not limited to these, and embodiments that use arbitrary OCT techniques different from these (for example, time domain OCT) can also be adopted.

In this specification, "image data" and "images" based thereon are not distinguished unless otherwise specified. In addition, unless otherwise specified, the site or tissue of the subject's eye is not distinguished from the image representing it.

<composition>
The exemplary ophthalmic apparatus 1 shown in FIG. 1 includes a fundus camera unit 2, an OCT unit 100, and an arithmetic and control unit 200. As shown in FIG. The retinal camera unit 2 is provided with an optical system and a mechanism for acquiring a front image of the eye to be examined E and an optical system and a mechanism for executing OCT. The OCT unit 100 is provided with an optical system and a mechanism for performing OCT. The arithmetic control unit 200 includes one or more processors configured to perform various types of processing (calculation, control, etc.). Furthermore, the ophthalmologic apparatus 1 includes two anterior eye cameras 300 for photographing the anterior eye from two directions.

The retinal camera unit 2 is provided with a chin rest and a forehead rest for supporting the subject's face. The chin rest and forehead rest correspond to the support 440 shown in FIGS. 4A and 4B. The base 410 houses a driving system such as the optical system driving section 2A and an arithmetic control circuit. A housing 420 provided on the base 410 houses an optical system. The objective lens 22 is housed in the lens housing portion 430 that protrudes from the front surface of the housing 420 .

Furthermore, the ophthalmologic apparatus 1 includes a lens unit for switching the site to which OCT is applied. Specifically, the ophthalmologic apparatus 1 includes an anterior segment OCT attachment 400 for applying OCT to the anterior segment. The anterior segment OCT attachment 400 may be configured in the same manner as the optical unit disclosed in Japanese Unexamined Patent Application Publication No. 2015-160103, for example.

As shown in FIG. 1, the anterior segment OCT attachment 400 can be arranged between the objective lens 22 and the eye E to be examined. When the anterior segment OCT attachment 400 is placed in the optical path, the ophthalmologic apparatus 1 can apply an OCT scan to the anterior segment. On the other hand, when the anterior segment OCT attachment 400 is retracted from the optical path, the ophthalmologic apparatus 1 can apply an OCT scan to the posterior segment. Movement of the anterior segment OCT attachment 400 is performed manually or automatically.

In another embodiment, an OCT scan can be applied to the posterior segment when the attachment is placed in the optical path, and an OCT scan can be applied to the anterior segment when the attachment is retracted from the optical path. you can Moreover, the measurement site that can be switched by the attachment is not limited to the posterior segment and the anterior segment of the eye, and may be any site of the eye. In addition, the configuration for switching the part to which the OCT scan is applied is not limited to such an attachment, and for example, a configuration including a lens that can be moved along the optical path, or a lens that can be inserted into and removed from the optical path It is also possible to adopt a configuration with

In this embodiment, the “processor” includes, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (for example, an SPLD (Simple Programmable Logic Device e), CPLD (Complex Programmable Logic Device), FPGA (Field Programmable Gate Array)) or the like. The processor implements the functions according to the embodiment by, for example, reading and executing a program stored in a storage circuit or storage device.

<Fundus camera unit 2>
The fundus camera unit 2 is provided with an optical system for photographing the fundus Ef of the eye E to be examined. The acquired digital image of the fundus oculi Ef (called a fundus image, a fundus photograph, etc.) is generally a front image such as an observed image or a photographed image. Observation images are obtained by moving image shooting using near-infrared light. The photographed image is a still image using flash light in the visible region.

The fundus camera unit 2 includes an illumination optical system 10 and an imaging optical system 30 . The illumination optical system 10 irradiates the eye E to be inspected with illumination light. The imaging optical system 30 detects return light of the illumination light with which the eye E to be examined is irradiated. Measurement light from the OCT unit 100 is guided to the subject's eye E through an optical path in the fundus camera unit 2 . Return light of the measurement light projected onto the eye E (for example, the fundus oculi Ef) is guided to the OCT unit 100 through the same optical path in the fundus camera unit 2 .

Light (observation illumination light) output from the observation light source 11 of the illumination optical system 10 is reflected by the concave mirror 12, passes through the condenser lens 13, passes through the visible cut filter 14, and becomes near-infrared light. Further, the observation illumination light is once converged in the vicinity of the photographing light source 15, reflected by the mirror 16, passed through the relay lens system 17, the relay lens 18, the diaphragm 19, and the relay lens system 20, to the perforated mirror 21. be guided. The observation illumination light is reflected by the periphery of the perforated mirror 21 (area around the perforation), passes through the dichroic mirror 46, is refracted by the objective lens 22, and illuminates the eye E (fundus oculi Ef). do. The return light of the observation illumination light from the subject's eye E is refracted by the objective lens 22, passes through the dichroic mirror 46, passes through the hole formed in the central region of the apertured mirror 21, and passes through the dichroic mirror 55. , through a focusing lens 31 and reflected by a mirror 32 . Further, this return light passes through the half mirror 33A, is reflected by the dichroic mirror 33, and is imaged on the light receiving surface of the image sensor 35 by the imaging lens . The image sensor 35 detects returned light at a predetermined frame rate. Note that the focus of the imaging optical system 30 is adjusted so as to match the fundus oculi Ef or the anterior segment of the eye.

The light (imaging illumination light) output from the imaging light source 15 irradiates the fundus oculi Ef through the same path as the observation illumination light. The return light of the imaging illumination light from the subject's eye E is guided to the dichroic mirror 33 through the same path as the return light of the observation illumination light, passes through the dichroic mirror 33 , is reflected by the mirror 36 , is reflected by the imaging lens 37 . An image is formed on the light receiving surface of the image sensor 38 .

A liquid crystal display (LCD) 39 displays a fixation target (fixation target image). A part of the light beam output from the LCD 39 is reflected by the half mirror 33 A, reflected by the mirror 32 , passes through the focusing lens 31 and the dichroic mirror 55 , and passes through the aperture of the apertured mirror 21 . The luminous flux that has passed through the aperture of the perforated mirror 21 is transmitted through the dichroic mirror 46, refracted by the objective lens 22, and projected onto the fundus oculi Ef. A fixation target is typically used for eye guidance and fixation. A direction in which the line of sight of the subject's eye E is guided (and fixed), that is, a direction in which fixation of the subject's eye E is encouraged is called a fixation position.

By changing the display position of the fixation target image on the screen of the LCD 39, the fixation position can be changed. Examples of fixation positions include a fixation position for acquiring an image centered on the macula, a fixation position for acquiring an image centered on the optic disc, and a position between the macula and the optic disc ( There is a fixation position for acquiring an image centered on the center of the eye fundus, and a fixation position for acquiring an image of a site far away from the macula (eye fundus periphery).

A graphical user interface (GUI) or the like may be provided for specifying at least one such exemplary fixation position. Further, a GUI or the like for manually moving the fixation position (the display position of the fixation target) can be provided. It is also possible to apply a configuration that automatically sets the fixation position.

A configuration for presenting a fixation target whose fixation position is changeable to the eye to be examined E is not limited to a display device such as an LCD. For example, a device (fixation matrix) in which a plurality of light-emitting units (light-emitting diodes, etc.) are arranged in a matrix can be employed instead of the display device. In this case, the fixation position of the subject's eye E by the fixation target can be changed by selectively lighting a plurality of light emitting units. As another example, a device with one or more movable light emitters can generate a fixation target whose fixation position can be changed.

The alignment optical system 50 generates an alignment index used for alignment of the optical system with respect to the eye E to be examined. Alignment light output from a light-emitting diode (LED) 51 passes through an aperture 52, an aperture 53, and a relay lens 54, is reflected by a dichroic mirror 55, passes through the aperture of the perforated mirror 21, and passes through the dichroic mirror 46. It is transmitted and projected onto the subject's eye E via the objective lens 22 . The return light of the alignment light from the eye to be examined E is guided to the image sensor 35 through the same path as the return light of the observation illumination light. Manual alignment or automatic alignment can be performed based on the received light image (alignment index image).

Note that the alignment method applicable to the embodiment is not limited to the method using such an alignment index, and the method using the anterior eye camera 300 (described later), or the method of projecting light obliquely onto the cornea. It may be any known technique, such as an optical lever technique configured to detect corneal reflected light in opposite directions.

The focus optical system 60 generates a split index used for focus adjustment of the eye E to be examined. The focus optical system 60 is moved along the optical path of the illumination optical system 10 (illumination optical path) in conjunction with the movement of the imaging focusing lens 31 along the optical path of the imaging optical system 30 (imaging optical path). The reflecting bar 67 is inserted into and removed from the illumination optical path. When performing focus adjustment, the reflecting surface of the reflecting bar 67 is arranged at an angle in the illumination optical path. Focus light output from the LED 61 passes through a relay lens 62, is split into two light beams by a split index plate 63, passes through a two-hole diaphragm 64, is reflected by a mirror 65, and is reflected by a condenser lens 66 onto a reflecting rod 67. is once imaged on the reflective surface of , and then reflected. Further, the focused light passes through the relay lens 20 , is reflected by the perforated mirror 21 , passes through the dichroic mirror 46 , and is projected onto the subject's eye E via the objective lens 22 . The return light of the focus light from the subject's eye E (reflected light from the fundus, etc.) is guided to the image sensor 35 through the same path as the return light of the alignment light. Manual focusing and autofocusing can be performed based on the received light image (split index image).

Diopter correction lenses 70 and 71 can be selectively inserted in the imaging optical path between the apertured mirror 21 and the dichroic mirror 55 . The dioptric correction lens 70 is a plus lens (convex lens) for correcting high hyperopia. The dioptric correction lens 71 is a minus lens (concave lens) for correcting strong myopia.

The dichroic mirror 46 synthesizes the fundus imaging optical path and the OCT optical path (measurement arm). The dichroic mirror 46 reflects light in the wavelength band used for OCT and transmits light for photographing the fundus. The measurement arm is provided with a collimator lens unit 40, a retroreflector 41, a dispersion compensation member 42, an OCT focusing lens 43, an optical scanner 44, and a relay lens 45 in order from the OCT unit 100 side.

The retroreflector 41 is movable along the path of the measuring light LS incident on it, thereby changing the length of the measuring arm. The change in measurement arm length is used, for example, for optical path length correction according to the axial length of the eye, adjustment of the interference state, and the like.

The dispersion compensating member 42 works together with a dispersion compensating member 113 (described later) arranged on the reference arm to match the dispersion characteristics of the measurement light LS and the reference light LR.

An OCT focusing lens 43 is moved along the measuring arm to focus the measuring arm. In addition, the movement of the imaging focusing lens 31, the movement of the focusing optical system 60, and the movement of the OCT focusing lens 43 can be controlled in a coordinated manner.

The optical scanner 44 is substantially arranged at a position optically conjugate with the pupil of the eye E to be examined. A light scanner 44 deflects the measuring light LS guided by the measuring arm. The optical scanner 44 is, for example, a galvanometer scanner capable of two-dimensional scanning. Typically, the optical scanner 44 includes a one-dimensional scanner (x-scanner) for deflecting the measurement light in ±x directions and a one-dimensional scanner (y-scanner) for deflecting the measurement light in ±y directions. including. In this case, for example, either one of these one-dimensional scanners is placed at a position optically conjugate with the pupil, or a position optically conjugate with the pupil is placed between these one-dimensional scanners.

<OCT unit 100>
The exemplary OCT unit 100 shown in FIG. 2 is provided with optics for performing swept-source OCT. This optical system includes interference optics. This interference optical system divides the light from the wavelength tunable light source into measurement light and reference light, and superimposes the return light of the measurement light projected on the subject's eye E and the reference light that has passed through the reference optical path to obtain interference light. and detect this interference light. Data (detection signal) obtained by detecting the interference light is a signal representing the spectrum of the interference light and is sent to the arithmetic control unit 200 .

The light source unit 101 includes, for example, a near-infrared tunable laser that changes the wavelength of emitted light at high speed. Light L0 output from the light source unit 101 is guided to the polarization controller 103 through the optical fiber 102, and the polarization state is adjusted. Further, the light L0 is guided by the optical fiber 104 to the fiber coupler 105 and split into the measurement light LS and the reference light LR. The optical path of the measurement light LS is called a measurement arm or the like, and the optical path of the reference light LR is called a reference arm or the like.

The reference light LR generated by the fiber coupler 105 is guided by the optical fiber 110 to the collimator 111 , converted into a parallel beam, and guided to the retroreflector 114 via the optical path length correction member 112 and the dispersion compensation member 113 . The optical path length correction member 112 acts to match the optical path length of the reference light LR and the optical path length of the measurement light LS. The dispersion compensation member 113 works together with the dispersion compensation member 42 arranged on the measurement arm to match the dispersion characteristics between the reference light LR and the measurement light LS. The retroreflector 114 is movable along the optical path of the reference beam LR incident on it, thereby changing the length of the reference arm. A change in the reference arm length is used, for example, for optical path length correction according to the axial length of the eye, adjustment of the interference state, and the like.

The reference light LR that has passed through the retroreflector 114 passes through the dispersion compensating member 113 and the optical path length correcting member 112 , is converted by the collimator 116 from a parallel beam into a focused beam, and enters the optical fiber 117 . The reference light LR incident on the optical fiber 117 is guided to the polarization controller 118 to have its polarization state adjusted, guided to the attenuator 120 through the optical fiber 119 to have its light amount adjusted, and passed through the optical fiber 121 to the fiber coupler 122. be guided.

On the other hand, the measurement light LS generated by the fiber coupler 105 is guided to the collimator lens unit 40 through the optical fiber 127 and converted into a parallel light beam, which is then converted into a parallel light beam by the retroreflector 41, the dispersion compensating member 42, the OCT focusing lens 43, and the optical scanner 44. , and a relay lens 45, reflected by a dichroic mirror 46, refracted by an objective lens 22, and projected onto an eye E to be examined. The measurement light LS is scattered and reflected at various depth positions of the eye E to be examined. The return light of the measurement light LS from the subject's eye E travels in the opposite direction through the measurement arm, is guided to the fiber coupler 105 , and reaches the fiber coupler 122 via the optical fiber 128 .

The fiber coupler 122 superimposes the measurement light LS input via the optical fiber 128 and the reference light LR input via the optical fiber 121 to generate interference light. The fiber coupler 122 splits the generated interference light at a predetermined splitting ratio (for example, 1:1) to generate a pair of interference lights LC. A pair of interference lights LC are guided to detector 125 through optical fibers 123 and 124, respectively.

Detector 125 includes, for example, a balanced photodiode. A balanced photodiode includes a pair of photodetectors that respectively detect a pair of interference lights LC, and outputs a difference between a pair of detection signals obtained by these. Detector 125 sends this output (a detected signal such as a differential signal) to data acquisition system (DAQ) 130 .

A clock KC is supplied from the light source unit 101 to the data collection system 130 . The clock KC is generated in the light source unit 101 in synchronization with the output timing of each wavelength swept within a predetermined wavelength range by the wavelength tunable light source. The light source unit 101, for example, splits the light L0 of each output wavelength to generate two split lights, optically delays one of these split lights, combines these split lights, and produces the resulting combined light. A clock KC is generated based on the detection signal. The data acquisition system 130 samples the detection signal (difference signal) input from the detector 125 based on the clock KC. Data collection system 130 sends the data obtained by this sampling to arithmetic and control unit 200 .

In this example, both an element for changing the measurement arm length (eg retroreflector 41) and an element for changing the reference arm length (eg retroreflector 114 or reference mirror) are provided. However, only one of these elements may be provided. Also, the elements for changing the difference (optical path length difference) between the measurement arm length and the reference arm length are not limited to these, and arbitrary elements (optical members, mechanisms, etc.) can be adopted. .

<Arithmetic control unit 200>
The arithmetic control unit 200 controls each part of the ophthalmologic apparatus 1 . Further, the arithmetic control unit 200 executes various kinds of arithmetic processing. For example, the arithmetic and control unit 200 performs signal processing such as Fourier transform on the spectral distribution based on the group of sampling data obtained by the data acquisition system 130 for each series of wavelength scans (for each A line), so that each A Form a reflection intensity profile in the line. Furthermore, the arithmetic and control unit 200 forms image data by imaging the reflection intensity profile of each A-line. Arithmetic processing therefor is the same as in conventional swept source OCT.

The arithmetic control unit 200 includes, for example, a processor, RAM (Random Access Memory), ROM (Read Only Memory), hard disk drive, communication interface, and the like. Various computer programs are stored in a storage device such as a hard disk drive. The arithmetic and control unit 200 may include an operation device, an input device, a display device, and the like.

<User Interface 240>
User interface 240 includes display unit 241 and operation unit 242 . Display unit 241 includes display device 3 . The operation unit 242 includes various operation devices and input devices. The user interface 240 may include a device, such as a touch panel, that combines a display function and an operation function. It is also possible to construct embodiments that do not include at least a portion of user interface 240 . For example, the display device may be an external device connected to the ophthalmic imaging equipment.

<Anterior segment camera 300>
The anterior segment camera 300 photographs the anterior segment of the subject's eye E from two or more different directions. The anterior segment camera 300 includes an imaging device such as a CCD image sensor or a CMOS image sensor. In this embodiment, two anterior eye cameras 300 are provided on the subject side surface of the retinal camera unit 2 (see anterior eye cameras 300A and 300B shown in FIG. 4A). As shown in FIGS. 1 and 4A, the anterior cameras 300A and 300B are located off the optical path passing through the objective lens 22. As shown in FIG. One or both of the anterior cameras 300A and 300B may be designated 300 hereinafter.

In this embodiment, two anterior cameras 300A and 300B are provided, but typically the number of anterior cameras may be any number greater than or equal to two. Considering the arithmetic processing to be described later, a configuration capable of imaging the anterior segment from two different directions is sufficient (but not limited to this). One or more movable anterior eye cameras 300 may also be provided.

In this embodiment, an anterior segment camera 300 is provided separately from the illumination optical system 10 and the imaging optical system 30, but at least the imaging optical system 30 can be used to perform imaging of the anterior segment. That is, one of the two or more anterior eye cameras may include the imaging optical system 30 . The anterior segment camera 300 according to this embodiment may be capable of photographing the anterior segment from two (or more) different directions.

Arrangements may be provided for illuminating the anterior segment. The anterior segment illumination means includes, for example, one or more light sources. Typically, at least one light source (eg, an infrared light source) can be provided near each of the two or more anterior cameras.

Two or more anterior segment cameras can image the anterior segment substantially simultaneously from two or more different directions. "Substantially simultaneously" means that in addition to the case where the imaging timings of two or more anterior segment cameras are simultaneous, for example, it is acceptable that there is a difference in the imaging timings that can be ignored due to eye movement. show. Such substantially simultaneous photographing makes it possible to obtain images of the subject's eye E at substantially the same position and orientation with two or more anterior eye cameras.

The photography by the two or more anterior segment cameras may be video photography or still image photography. In the case of video shooting, by controlling the shooting start timing to match, or by controlling the frame rate and the shooting timing of each frame, it is possible to realize substantially simultaneous shooting of the anterior segment as described above. . On the other hand, in the case of still image shooting, this can be achieved by controlling the shooting timing to match.

<Control system>
An example of the configuration of the control system (processing system) of the ophthalmologic apparatus 1 is shown in FIGS. 3A and 3B. The control section 210, the image forming section 220, and the data processing section 230 are provided in the arithmetic control unit 200, for example.

<Control unit 210>
The control unit 210 includes a processor and controls each unit of the ophthalmologic apparatus 1 . Control unit 210 includes main control unit 211 and storage unit 212 .

<Main control unit 211>
The main control unit 211 includes a processor and controls each element of the ophthalmologic apparatus 1 (including the elements shown in FIGS. 1 to 3B). The main control unit 211 is implemented by cooperation of hardware including circuits and control software.

The photographing focusing lens 31 arranged in the photographing optical path and the focusing optical system 60 arranged in the illumination optical path are moved by a photographing focus driving section (not shown) under the control of the main control section 211 . A retroreflector 41 provided on the measurement arm is moved by a retroreflector (RR) driving section 41A under the control of the main control section 211 . The OCT focus lens 43 placed on the measurement arm is moved by the OCT focus driver 43A under control of the main controller 211 . The optical scanner 44 provided on the measurement arm operates under the control of the main controller 211 . A retroreflector 114 located on the reference arm is moved by a retroreflector (RR) driver 114A under the control of the main controller 211 . Each of the mechanisms illustrated here typically includes an actuator such as a pulse motor that operates under the control of main control section 211 .

The moving mechanism 150 moves, for example, at least the retinal camera unit 2 three-dimensionally. In a typical example, the moving mechanism 150 includes an x stage that can move in ±x directions (horizontal direction), an x moving mechanism that moves the x stage, and a y stage that can move in ±y directions (vertical direction). , a y-moving mechanism for moving the y-stage, a z-stage movable in the ±z direction (depth direction), and a z-moving mechanism for moving the z-stage. Each of these moving mechanisms includes an actuator such as a pulse motor that operates under control of the main control section 211 .

<Storage unit 212>
The storage unit 212 stores various data. The data stored in the storage unit 212 includes, for example, image data of an OCT image, image data of a fundus image, information on an eye to be examined, and the like. The eye information to be examined includes subject information such as a patient ID and name, left/right eye identification information, electronic medical record information, and the like.

The storage unit 212 stores in advance aberration information (not shown). In the aberration information, for each anterior eye camera 300, information on distortion occurring in the captured image due to the influence of the optical system mounted thereon is recorded. Here, the optical system mounted on the anterior eye camera 300 includes an optical element such as a lens that generates distortion aberration. Aberration information can be said to be a parameter that quantifies the distortion that these optical elements give to a captured image.

An example of a method of generating aberration information will be described. Considering the instrumental error (difference in distortion aberration) of the anterior eye camera 300, the following measurements are performed for each anterior eye camera 300. FIG. An operator prepares a predetermined reference point. A reference point is a shooting target used to detect distortion aberration. The operator takes multiple shots while changing the relative position between the reference point and the anterior eye camera 300 . Thereby, a plurality of photographed images of the reference point photographed from different directions are obtained. The operator generates the aberration information of the anterior eye camera 300 by analyzing the captured images with a computer. The computer that performs this analysis processing may be the data processing unit 230 or any other computer (computer for inspection before product shipment, computer for maintenance, etc.).

An analytical process for generating aberration information includes, for example, the following steps:
an extraction step of extracting an image region corresponding to a reference point from each photographed image;
A distribution state calculation step of calculating a distribution state (coordinates) of an image area corresponding to a reference point in each captured image;
Distortion aberration calculation step of calculating a parameter representing distortion aberration based on the obtained distribution state;
a correction coefficient calculation step of calculating coefficients for correcting distortion based on the obtained parameters;

Parameters related to the distortion aberration given to the image by the optical system include principal point distance, principal point position (vertical direction, lateral direction), lens distortion (radial direction, tangential direction), and the like. The aberration information is configured as information (for example, table information) that associates the identification information of each anterior eye camera 300 with the corresponding correction coefficients. The aberration information generated in this manner is stored in the storage section 212 by the main control section 211 . Generation of such aberration information and aberration correction based thereon are called camera calibration or the like.

<Image forming unit 220>
The imager 220 forms OCT image data based on the data collected by the data collection system 130 . Image forming unit 220 includes a processor. The image forming unit 220 is implemented by cooperation of hardware including circuits and image forming software.

The image forming section 220 forms cross-sectional image data based on the data collected by the data collection system 130 . This processing includes signal processing such as denoising (noise reduction), filtering, and fast Fourier transform (FFT), similar to conventional swept-source OCT.

The image data formed by the image forming unit 220 is a group of images formed by imaging reflection intensity profiles in a plurality of A-lines (scan lines along the z-direction) arranged in the area to which the OCT scan is applied. 1 is a data set containing image data (a group of A-scan image data);

The image data formed by the image forming unit 220 is, for example, one or more B-scan image data or stack data formed by embedding a plurality of B-scan image data in a single three-dimensional coordinate system. The image forming unit 220 can also construct volume data (voxel data) by voxelizing the stack data. Stack data and volume data are typical examples of three-dimensional image data represented by a three-dimensional coordinate system.

The image forming section 220 can process three-dimensional image data. For example, the image forming unit 220 can construct new image data by applying rendering to the 3D image data. Rendering techniques include volume rendering, maximum intensity projection (MIP), minimum intensity projection (MinIP), surface rendering, and multiplanar reconstruction (MPR). Further, the image forming unit 220 can construct projection data by projecting the three-dimensional image data in the z direction (A-line direction, depth direction). Also, the image forming unit 220 can construct a shadowgram by projecting a portion of the three-dimensional image data in the z-direction. A part of the three-dimensional image data projected to construct the shadowgram is set using, for example, segmentation.

<Data processing unit 230>
The data processing unit 230 executes various data processing. For example, the data processing unit 230 can apply image processing or analysis processing to OCT image data, or apply image processing or analysis processing to observed image data or photographed image data. The data processing unit 230 includes, for example, at least one of a processor and a dedicated circuit board.

<Data Acquisition Unit 250>
Please refer to FIG. 3B below. The data acquisition unit 250 is configured to optically acquire data of the eye E to be examined. In particular, the data acquisition unit 250 can project light onto the fundus oculi Ef and acquire data of the subject's eye E based on the return light. The data acquisition unit 250 can acquire image data by applying OCT to the eye E to be examined. The data acquisition section 250 includes a group of elements forming a measurement arm provided in the retinal camera unit 2 , a group of elements provided in the OCT unit 100 , and an image forming section 220 . In another example, the data acquisition unit 250 may include a configuration (illumination optical system 10, imaging optical system 30, etc.) for acquiring a fundus image.

The data acquisition unit 250 of this example also functions as an OCT unit that applies an OCT scan to the three-dimensional region of the anterior segment of the eye E to be examined and collects OCT data. When the data acquisition unit 250 is used as the OCT unit, the anterior segment OCT attachment 400 is inserted into the optical path. When the data acquisition unit 250 acquires data of the subject's eye E by projecting light onto the fundus oculi Ef, the anterior segment OCT attachment 400 is retracted from the optical path.

Thus, in this example, both anterior segment OCT and fundus OCT can be performed, but embodiments are not limited to this. For example, instead of or in addition to fundus OCT, the ophthalmologic apparatus according to the embodiment can perform fundus photography (fundus camera, SLO), axial length measurement, eye refraction test, and eye aberration measurement (wavefront analyzer). , a visual field test (microperimeter, perimeter) may be performed.

Further, in this example, an optical system (a data acquisition optical system included in the data acquisition unit 250) for projecting light onto the fundus oculi Ef to acquire data of the eye to be examined E, and an optical system for the anterior segment OCT (anterior segment OCT optical system) includes a common scanning optical system. This common scanning optical system includes a group of elements forming a measurement arm provided in the retinal camera unit 2 and a group of elements provided in the OCT unit 100 . In other embodiments, it is not necessary to adopt such a configuration, and for example, the data acquisition optical system and the anterior segment OCT optical system may be provided separately.

<Alignment system 260>
Alignment system 260 includes elements for aligning the data acquisition optics. The alignment system 260 may include an alignment optical system 50 for projecting an alignment index onto the subject's eye E (first configuration). The alignment system 260 also includes two anterior eye cameras 300 and a position information acquisition unit 231 (described later) that obtains the three-dimensional position of the subject's eye E from two anterior eye images obtained substantially simultaneously by these cameras. (second configuration). Further, the alignment system 260 may include a light projection system, a light receiving system, and a processor for determining the position of the subject's eye E from the output from the light receiving system for performing alignment using an optical lever (third configuration).

The ophthalmologic apparatus 1 according to this embodiment includes both the first and second configurations among the first to third configurations. There may be one, either two or three. Alternatively, the alignment system 260 may include configurations other than the first to third configurations. In other words, the alignment method performed by the alignment system 260 is arbitrary.

<Example of control unit 210>
The controller 210 illustrated in FIG. 3B includes a drive controller 2101 and a display controller 2102 . A drive control unit 2101 controls the moving mechanism 150 . A display control unit 2102 controls the user interface 240 (display unit 241). The drive control unit 2101 and the display control unit 2102 are included in the main control unit 211 shown in FIG. 3A.

<Example of data processing unit 230>
The data processing unit 230 illustrated in FIG. 3B includes a position information acquisition unit 231, a determination unit 232, a cloudy area identification unit 233, and a movement target determination unit 234.

<Position information acquisition unit 231>
The position information acquisition unit 231 analyzes the two anterior segment images acquired by the two anterior segment cameras 300 capturing the anterior segments of the eye E to be inspected substantially simultaneously, and obtains the 3 Dimensional position can be determined. An example of processing executed by the position information acquisition unit 231 will be described below.

First, the position information acquisition unit 231 can correct the distortion of the captured image obtained by the anterior eye camera 300 based on the aberration information stored in the storage unit 212 . This correction can be performed, for example, by known image processing techniques based on correction coefficients for correcting distortion. Note that when the distortion aberration that the optical system of the anterior eye camera 300 gives to the captured image is sufficiently small, the aberration information and the correction using it may be unnecessary.

Next, the position information acquisition unit 231 can specify an image region (pupil region) corresponding to the pupil of the subject's eye E based on the distribution of pixel values (eg, luminance values) of the captured image. Since the pupil is generally expressed with lower luminance than other parts, it is possible to specify the pupil region by searching for the low luminance image region. At this time, the pupil region may be specified in consideration of the shape of the pupil. For example, the pupil region can be identified by searching for a substantially circular, low-intensity image region.

Subsequently, the position information acquisition unit 231 can identify the central position of the identified pupillary region. Utilizing the fact that the pupil is substantially circular as described above, the position information acquisition unit 231 performs, for example, a process of identifying the contour of the pupil region, a process of obtaining an approximate ellipse (or approximate circle) of the contour, and a process of identifying the center position of this approximated ellipse (or approximated circle). The center position of the approximate ellipse (or approximate circle) specified in this way is used as the pupil center of the eye E to be examined. As another example of processing for obtaining the center of the pupil, the position information acquisition unit 231 can obtain the center of gravity of the pupil region and set it as the center of the pupil.

The position information acquisition unit 231 obtains the center of the pupil of the subject's eye E based on the position (and imaging magnification) of the anterior eye camera 300 and the position of the center of the pupil in the two captured images specified in the preceding processing. A three-dimensional position can be determined.

FIG. 5A is a top view showing the positional relationship between the subject's eye E, the anterior eye camera 300A, and the anterior eye camera 300B. FIG. 5B is a side view showing the positional relationship between the subject's eye E, the anterior eye camera 300A, and the anterior eye camera 300B. The distance (baseline length) between the anterior eye camera 300A and the anterior eye camera 300B is represented by "B". The distance (shooting distance) between the base line of the anterior eye cameras 300A and 300B and the pupil center P of the subject's eye E is represented by "H". The distance (screen distance) between the anterior eye camera 300A and its screen plane is represented by "f".

In such an arrangement state, the resolution of images captured by the anterior eye cameras 300A and 300B is expressed by the following equation. Here, Δp represents pixel resolution.

Resolution in xy direction (planar resolution): Δxy=H×Δp/f
Resolution in z direction (depth resolution): Δz=H×H×Δp/(B×f)

For example, the position information acquisition unit 231 determines the positions of the anterior eye cameras 300A and 300B (which are known) and the position corresponding to the pupil center P in the two captured images, and the positional relationships shown in FIGS. 5A and 5B. The three-dimensional position of the pupil center P can be calculated by applying a known trigonometry method that takes into account .

Note that even when a feature point other than the center of the pupil is applied, the position information acquisition unit 231 applies the same processing as described above to obtain a three-dimensional image of the feature point based on the pixel value distribution of the captured image. It is possible to determine the position.

The position information acquired by the position information acquisition unit 231 (for example, information indicating the three-dimensional position of the pupil center) is sent to the control unit 210 . The drive control unit 2101 applies alignment control to the moving mechanism 150 based on this position information. This alignment control is an example of the aforementioned auto alignment.

<Determination unit 232>
As described above, the data acquisition unit 250 projects light onto the fundus oculi Ef and acquires data of the subject's eye E based on the return light. Based on the data acquired by the data acquisition unit 250, the determination unit 232 determines whether or not to apply a three-dimensional OCT scan to the anterior segment of the eye E to be examined. Typically, after the above-described auto-alignment is performed, the data acquisition section 250 acquires data, and the determination section 232 performs determination.

The data acquired by the data acquisition unit 250 of this example is, for example, OCT data. Examples of OCT data are A-scan image data for axial length measurement or imaging. In this case, the determination unit 232 determines, for example, whether or not the luminance of this A-scan image data exceeds a predetermined threshold. Typically, it is determined whether a statistical value (for example, sum, average, maximum value) of luminance values of a group of pixels included in the A-scan image data exceeds a threshold. If this statistic value does not exceed the threshold, it is suggested that the measurement light LS and/or its return light has passed through an opaque portion within the eye E to be examined. In this threshold processing, for example, a default threshold or a threshold set according to A-scan image data or the like is used.

Even when the data acquisition unit 250 acquires other types of data, if the light to be projected onto the fundus oculi Ef and/or its return light passes through the opacity part in the eye to be examined E, the acquired data information indicating the intensity of (eg, luminance) is reduced. The determination unit 232 and the data acquisition unit 250 can make similar determinations based on the intensity of the data acquired by the data acquisition unit 250 .

<Muddy area specifying unit 233>
The opacity region specifying unit 233 analyzes OCT data acquired by three-dimensional OCT scanning of the anterior segment of the subject's eye E to specify the opacity region of the anterior segment. The opacity region is an image region corresponding to opacity inside the eye E to be examined. The region of opacity corresponds to the opacity of the medium translucency as seen in cataractous eyes.

For example, the opacity region identifying unit 233 analyzes a three-dimensional OCT image of the anterior segment or a projection image (or shadowgram) based thereon. The opaque region specifying unit 233 can obtain the distribution of pixel values (for example, luminance values) of such an OCT image and specify the opaque region based on this distribution. OCT images of the anterior segment show opacified areas as shadows. The opaque region specifying unit 233 specifies pixels whose brightness value is equal to or less than a predetermined threshold value by applying threshold processing regarding brightness to the OCT image. The pixel group specified by this is set to the cloudy area. In this threshold processing, for example, a default threshold or a threshold set according to an OCT image or the like is used.

<Movement target determination unit 234>
The moving target determination unit 234 determines the moving target of the data acquisition optical system included in the data acquisition unit 250 based on the cloudy area specified by the cloudy area specifying unit 233 . The determined moving target is used for alignment of the data acquisition optical system.

For example, an image expressing the anterior segment of the subject's eye E and the opacity area specified by the opacity area specifying part 233 (information indicating its position/distribution) are input to the movement target determination unit 234 . The image representing the anterior segment is, for example, the OCT data processed by the opacity region specifying unit 233, an image obtained by processing this OCT data (eg, projection image, shadowgram), the fundus camera unit 2 An image obtained by processing the anterior eye image obtained by the anterior eye image obtained by the anterior eye camera 300 and the two anterior eye images obtained by the two anterior eye cameras 300 (for example, a front image).

If the image representing the anterior segment is neither the OCT data processed by the opacity region identification unit 233 nor the processed image of this OCT data, the data processing unit 230 extracts the image representing the anterior segment and this OCT A registration can be made between the data (or its processed image). Registration may be, for example, image matching using feature points. According to the registration, the position (distribution) of opacified regions in the image representing the anterior segment can be obtained.

In addition, when the image representing the anterior segment is OCT data subjected to processing by the opacity region specifying unit 233 or a processed image of this OCT data, the image representing the anterior segment and the opacity region Since there is a trivial correspondence between , there is no need to apply registration.

The movement target determination unit 234 can determine the movement target of the data acquisition optical system so that the image representing the anterior segment passes through a position different from the opacity region. In other words, the movement target determination unit 234 can determine the movement target of the data acquisition optical system so that the measurement light LS projected by the data acquisition unit 250 is guided while avoiding turbidity in the eye E to be examined.

The movement target determination unit 234 can determine the movement target of the data acquisition optical system in consideration of the beam diameter of the measurement light LS. For example, the movement target determination unit 234 can determine the movement target of the data acquisition optical system such that the entire beam cross section of the measurement light LS passes through the non-turbidity portion.

In order to reduce the speckle noise mixed in the image, the controller 210 can control the optical scanner 44 so as to temporally change the deflection direction of the measurement light LS. In this case, the movement target determining section 234 can determine the movement target of the data acquisition optical system in consideration of changes in the passing position of the measurement light LS. For example, the movement target determination unit 234 can determine the movement target of the data acquisition optical system so that the change range of the passing position of the measurement light LS at a predetermined depth position within the eye E to be examined does not overlap with the cloudy region. can. Since the optical scanner 44 is typically arranged at a position optically conjugated to the pupil of the eye E to be inspected, the measurement light LS passes through a location relatively far from the pupil (for example, the posterior surface of the crystalline lens). A movement target for the data acquisition optics can be determined such that the range of change in position does not overlap with the turbidity region. The distance between the pupil and the predetermined location may be, for example, a value obtained by measuring the subject's eye E or a value obtained from model eye data.

The movement target determined by the movement target determination unit 234 is, for example, information including at least the x-coordinate and the y-coordinate. The determined moving target is sent to the control unit 210 .

When automatically correcting the alignment of the data acquisition optical system, the drive control section 2101 can control the movement mechanism 150 based on the movement target determined by the movement target determination section 234 . For example, the drive control unit 2101 can control the movement mechanism 150 so that the data acquisition optical system is moved to a position corresponding to the x-coordinate and y-coordinate included in the movement target.

When manually correcting the alignment of the data acquisition optical system, the display control unit 2102 can cause the display unit 241 to display, for example, an image representing the anterior segment described above. The display control unit 2102 can display the alignment index image together with the image representing the anterior segment. The operation unit 242 is used by the user to perform alignment operations for the data acquisition optical system. The drive control section 2101 can control the moving mechanism 150 based on signals input from the operation section 242 . Thereby, the user can move the data acquisition optical system to a desired position.

When the alignment is manually corrected, the display control unit 2102 can cause the display unit 241 to display information for alignment operation (alignment support information) based on the movement target obtained by the movement target determination unit 234. can. Alignment assistance information may include, for example, information indicating a position corresponding to a moving target displayed together with an image representing the anterior segment. Alternatively, the alignment support information may be information indicating the operation direction (movement direction) and/or the operation amount (movement amount), such as an arrow image pointing from the current position of the data acquisition optical system to the position corresponding to the movement target. may contain. Such alignment support information is generated, for example, based on the x-coordinate and y-coordinate included in the moving target.

<motion>
An example of the operation of the ophthalmologic apparatus 1 according to this embodiment will be described. Alignment correction operations that can be performed by the ophthalmologic apparatus 1 will be described below.

<Automatic Alignment Correction>
FIG. 6 shows an example of the operation of the ophthalmologic apparatus 1 for automatically correcting the alignment of the data acquisition optical system.

(S1: Alignment start)
First, alignment of the data acquisition optical system using the alignment system 260 is started. This alignment may be manual alignment, but is typically auto alignment.

Auto-alignment can be performed using, for example, the anterior eye camera 300, the position information acquisition unit 231, the drive control unit 2101, and the like (stereo camera method). Alternatively, the auto-alignment may be any one of alignment using an alignment index generated by the alignment optical system 50, alignment using an optical lever, alignment using a Purkinje image, and alignment using other methods. .

(S2: Alignment completed)
The alignment in step S1 is completed when the alignment of the data acquisition optical system with respect to the subject's eye E falls within a predetermined allowable range.

For example, according to the auto-alignment of the stereo camera system in this embodiment, the optical axis of the data acquisition optical system is substantially aligned with the pupil center of the eye E to be inspected (alignment in the xy direction), and the eye E to be inspected and the data The distance from the acquisition optical system (for example, the objective lens 22) is approximately matched to a predetermined working distance (alignment in the z direction).

Upon completion of the alignment, known tracking for moving the data acquisition optical system in accordance with the movement of the eye E to be examined may be started.

(S3: Acquire data by projecting light toward the fundus)
Upon completion of the alignment, the control section 210 causes the data acquisition section 250 to acquire data. The data acquisition unit 250 of this example projects the measurement light LS toward the fundus Ef of the eye E to be examined, detects the interference light LC generated by superimposing the return light and the reference light LR, and detects the interference light LC. A-scan image data is formed from the data acquired by 130 .

(S4, S5: Determine whether to perform anterior segment OCT based on data)
The determination unit 232 determines whether to apply an OCT scan to the three-dimensional region of the anterior segment of the eye E to be examined based on the data acquired in step S3. If it is determined that an anterior segment OCT scan is to be performed (S5: Yes), the process proceeds to step S6.

If it is determined not to perform an anterior segment OCT scan (S5: No), the data acquired in step S3 is adopted as the imaging result or the measurement result. This completes the operation illustrated in FIG.

(S6: Apply 3D OCT to the anterior segment)
If it is determined in step S5 that anterior segment OCT is to be performed (S5: Yes), the anterior segment OCT attachment 400 is inserted between the objective lens 22 and the eye E to be examined. The control unit 210 controls the data acquisition unit 250 to apply three-dimensional OCT to the anterior segment of the eye E to be examined.

The data acquisition unit 250 (image forming unit 220) can form an image representing the anterior segment (projection image, shadowgram, etc.) from the 3D OCT image data obtained by the 3D OCT of the anterior segment. can.

Aside from the anterior segment OCT, it is also possible to obtain an image expressing the anterior segment using the fundus camera unit 2, the anterior segment camera 300, and the like.

(S7: Identify the opaque area in the front image)
The opacity region specifying unit 233 analyzes the three-dimensional OCT image data (or an image representing the anterior segment based thereon) acquired in step S6 to specify the opacity region of the anterior segment.

The display control unit 2102 can cause the display unit 241 to display information indicating the specified opacity region together with an image representing the anterior segment.

(S8: Determining the movement target of the data acquisition optical system)
The movement target determination unit 234 determines the movement target of the data acquisition optical system based on the turbidity area identified in step S7.

The movement target determination unit 234 determines the movement target so that the optical axis (measurement light LS) of the data acquisition optical system passes through a position different from the cloudy area. As described above, in determining the moving target, the beam diameter of the measurement light LS and/or the deflection range of the measurement light LS for speckle noise reduction may be considered.

The display control unit 2102 can cause the display unit 241 to display information indicating the determined movement target together with an image representing the anterior segment and/or information indicating the opacified region.

(S9: Move data acquisition optical system)
The drive control unit 2101 controls the movement mechanism 150 to move the optical axis of the data acquisition optical system to the position (x coordinate, y coordinate) indicated by the movement target determined in step S8.

(S10: Acquire data by projecting light toward the fundus)
After the movement of the data acquisition optical system in step S9 is completed, the control section 210 causes the data acquisition section 250 to acquire data. The data acquisition unit 250 of this example projects the measurement light LS toward the fundus Ef of the eye E to be examined, detects the interference light LC generated by superimposing the return light and the reference light LR, and detects the interference light LC. OCT image data is formed from the data acquired by 130 .

For example, the OCT image data is A-scan OCT image data, and the data processing unit 230 calculates the cornea-retina distance from this A-scan OCT image data. This cornea-retina distance can be referred to as an approximation of the axial length of the eye. In other examples, the OCT image data is B-scan image data or 3D scan image data.

The data acquisition performed in step S10 is not limited to OCT, for example fundus photography (retinal camera, SLO), eye refraction examination, ocular aberration measurement (wavefront analyzer), or visual field examination (microperimeter, perimeter). may be With this, the operation illustrated in FIG. 6 is completed.

<Manual correction of alignment>
An example of the operation of the ophthalmic apparatus 1 for manually correcting the alignment of the data acquisition optics is shown in FIG.

(S21-S28)
Steps S21 to S28 are executed in the same manner as steps S1 to S8 in FIG. 6 (automatic correction), respectively.

(S29: Display the image of the anterior segment)
The display control unit 2102 causes the display unit 241 to display an image of the anterior segment of the eye E to be examined. This image may include, for example, at least one of an image representing the anterior segment and an observed image acquired in real time.

In addition, the display control unit 2102 can cause the display unit 241 to display information indicating the opacity region identified in step S27 together with the image of the anterior segment.

(S30: display alignment support information)
The display control unit 2102 causes the display unit 241 to display the alignment support information based on the moving target determined in step S28 together with the image of the anterior segment (and information indicating the opacity region).

(S31: User performs alignment operation)
The user corrects the alignment of the data acquisition optical system using the operation unit 242 while referring to the image of the anterior segment and the alignment support information (and information indicating the opacified region) displayed on the display unit 241. perform an operation.

(S32: Acquire data by projecting light toward the fundus)
For example, when the user inputs an alignment correction completion instruction or an OCT start instruction using the operation unit 242, the control unit 210 causes the data acquisition unit 250 to acquire data in the same manner as in step S10. Alternatively, in response to the fact that the ophthalmologic apparatus 1 has detected the completion of the alignment correction, the control section 210 causes the data acquisition section 250 to acquire data in the same manner as in step S10. This completes the operation illustrated in FIG.

<Modification>
A modification of the above embodiment will be described.

The data processing unit 230 in the above-described embodiment applies OCT scanning to the three-dimensional region of the anterior segment of the subject's eye E, analyzes OCT data collected, and identifies the opacified region of the anterior segment. The cloudy area is an area unsuitable for imaging or measurement performed by projecting light onto the fundus oculi Ef by the data acquisition unit 250 . Conversely, the data acquisition unit 250 can identify a region suitable for imaging or measurement by projecting light onto the fundus oculi Ef. Such embodiments are described below.

FIG. 8 shows the configuration of an ophthalmologic apparatus according to a modification. The configuration shown in FIG. 8 can be applied instead of the configuration shown in FIG. 3B of the above embodiment. The difference between the configuration shown in FIG. 3B and the configuration shown in FIG. 8 is that data processing section 230 in FIG. 3B is replaced with data processing section 230A in FIG. The difference between the data processing section 230 and the data processing section 230A is that the opaque area identifying section 233 of the data processing section 230 is replaced with the target area identifying section 235 of the data processing section 230A. In the modified examples, elements similar to those of the above embodiment are denoted by the same reference numerals unless otherwise specified. Also, the drawings of the above embodiments (eg, FIGS. 1, 2, 3A, etc.) may be referred to.

It should be noted that it is also possible to employ a configuration that includes both the opaque area identifying section 233 and the target area identifying section 235 and can selectively use them.

The target area identification unit 235 will be described. The target region identifying unit 235 analyzes the OCT data collected by applying the OCT scan to the three-dimensional region of the anterior segment of the eye E to be examined, and the data acquisition unit 250 emits light (for example, the measurement light LS ) to identify a region of interest for projecting.

The target area specifying unit 235 includes, for example, a process of specifying a cloudy area similarly to the cloudy area specifying unit 233 and a process of specifying a target area based on the specified cloudy area. The latter process includes, for example, a process of obtaining a complement of the cloudy area when the pupil area is the whole set and the opaque area is a subset thereof.

Another example will be described. The target region identifying unit 235 analyzes a three-dimensional OCT image of the anterior segment or a projection image (or shadowgram) based thereon. The target region specifying unit 235 can obtain the distribution of pixel values (for example, luminance values) of such an OCT image and specify the target region based on this distribution. For example, the target region identification unit 235 identifies pixels whose luminance values exceed a predetermined threshold by applying threshold processing relating to luminance to the OCT image. The specified pixel group is set as the target area. In this threshold processing, for example, a default threshold or a threshold set according to an OCT image or the like is used.

The movement target determination section 234 can determine the movement target of the data acquisition optical system based on the target area identified by the target area identification section 235 . The determined moving target is used for alignment of the data acquisition optical system.

For example, an image representing the anterior segment of the subject's eye E and the target region specified by the target region specifying unit 235 (information indicating its position/distribution) are input to the movement target determination unit 234 . The type of image representing the anterior segment and the registration are the same as in the above embodiment.

The movement target determination unit 234 can determine the movement target of the data acquisition optical system so as to pass through the target region in the image representing the anterior segment. In other words, the movement target determination unit 234 can determine the movement target of the data acquisition optical system so that the measurement light LS projected by the data acquisition unit 250 is guided while avoiding turbidity in the eye E to be examined. At this time, it is possible to determine the moving target in consideration of the beam diameter and deflection range of the measurement light LS.

The movement target determined by the movement target determination unit 234 is, for example, information including at least the x-coordinate and the y-coordinate. The determined moving target is sent to the control unit 210 .

When automatically correcting the alignment of the data acquisition optical system, the drive control section 2101 can control the movement mechanism 150 based on the movement target determined by the movement target determination section 234 . For example, the drive control unit 2101 can control the movement mechanism 150 so that the data acquisition optical system is moved to a position corresponding to the x-coordinate and y-coordinate included in the movement target.

When manually correcting the alignment of the data acquisition optical system, the display control unit 2102 can cause the display unit 241 to display, for example, an image representing the anterior segment described above. The display control unit 2102 can display the alignment index image together with the image representing the anterior segment. The display control unit 2102 can also display alignment support information based on the movement target determined by the movement target determination unit 234 . The operation unit 242 is used by the user to perform alignment operations for the data acquisition optical system. The drive control section 2101 can control the moving mechanism 150 based on signals input from the operation section 242 . Thereby, the user can move the data acquisition optical system to a desired position.

<Other embodiments>
In the embodiments exemplified above, the case of performing alignment has been described, but it is also possible to apply the information on the opacity site obtained from the OCT data of the anterior segment to uses other than alignment. For example, it is possible to use the information on the opacified portion of the anterior segment for various displays. Exemplary embodiments for such displays are described below.

Such exemplary embodiments may include at least the configurations shown in FIGS. 1-3B or the configurations shown in FIGS. 1-3A and 8. FIG. A case including the former configuration will be described below as an example. In the following exemplary embodiments, elements similar to those in the above embodiments are denoted by the same reference numerals unless otherwise noted. In addition, the following exemplary embodiments may further include configurations shown in other drawings of the above embodiments.

The ophthalmologic apparatus 1 according to the exemplary embodiment applies an OCT scan to the three-dimensional region of the anterior segment of the eye E to be examined, collects OCT data, and analyzes the OCT data in the same manner as in the above embodiments. It is possible to identify areas of opacity in the anterior segment.

The display control unit 2102 can cause the display unit 241 to display an image representing the opacified region of the anterior segment. The aspect of the image representing the opaque area may be arbitrary. For example, the image representing the opaque area may include an image representing the outer edge (outline) of the opaque area. Also, the image representing the opaque area may include an image representing the entire opaque area.

The display control unit 2102 can display an image representing the opacity region together with the image of the subject's eye E acquired in advance.

The image of the subject's eye E may be an image acquired by the ophthalmologic apparatus 1 or may be an image acquired by another apparatus. When an image of the eye to be examined E acquired by another device is applied, the image of the eye to be examined E is input to the ophthalmologic apparatus 1 via, for example, a communication line or a recording medium.

The image of the subject's eye E may be an image representing any part of the subject's eye E. For example, an image representing the fundus oculi Ef, an image representing the anterior segment, or an image representing the range from the anterior segment to the posterior segment. It may be an image representing

The image of the subject's eye E may be an image acquired by any modality, examples of which include an image acquired by a fundus camera (retinal photograph), an image acquired by SLO (SLO image), and an image acquired by OCT scanning. There are an acquired image (OCT image), an image acquired by an anterior segment camera, and the like.

The image of the eye E to be inspected does not have to be an image obtained by photographing the eye E to be inspected. For example, as an image of the subject's eye E, a picture that schematically expresses the part of the eye, such as a schematic diagram, can be used.

When an image representing an opacity region is displayed together with an image of the fundus Ef of the eye to be examined E (or a schematic diagram of the fundus), the data processing unit 230 performs OCT scanning of the fundus image and the three-dimensional region of the anterior segment of the eye. Registration can be performed between the obtained 3D OCT data (or opacified regions identified from this 3D OCT data).

For example, registration can be performed by referring to the feature points of the anterior segment and the feature points of the fundus. Typically, it is possible to perform registration between the fundus image and the anterior segment 3D OCT data so that the position of the corneal vertex (or pupil center) and the position of the fovea coincide. . Alternatively, registration can be based on the location of the pupil region and the location of the macular region.

As another example, when the tissue of the fundus oculi Ef is depicted in the three-dimensional OCT data obtained by the OCT scan targeting the anterior segment, the image of the fundus oculi Ef in the three-dimensional OCT data is referenced to perform registration. It is possible to perform a ration.

As still another example, when a wide area image (typically an OCT image) representing the area from the anterior segment to the posterior segment of the eye to be examined E is obtained in advance, this wide area image may be used for registration. is possible.

FIG. 9A shows an exemplary display mode in which an image representing an opacified region is displayed together with an image of the fundus oculi Ef. In this example, the display control unit 2102 causes the display unit 241 to display the fundus image 500 and the opacity area image 510 acquired by the fundus camera unit 2 (or other fundus imaging device). More specifically, the display control unit 2102 superimposes the opacity area image 510 on the fundus image 500 and displays it, for example, based on the result of the registration described above. This makes it possible to easily grasp the positional relationship between the fundus oculi Ef and the opacity site.

In the example shown in FIG. 9A, the part of the fundus oculi Ef located under the opacity region image 510 cannot be observed. Therefore, for example, as shown in FIG. 9B, a cloudy region image 520 with transparency (alpha value) set to a value greater than zero can be displayed superimposed on the fundus image 500 . Here, the opacity value may be freely changed using the operation unit 242 . By displaying such a cloudy area image 520 superimposed on the fundus image 500, it is possible to observe the part of the fundus oculi Ef located under the cloudy area image 520. FIG. A similar effect can be obtained when an image representing the outer edge of the opaque area is displayed as the image of the opaque area.

When displaying an opacity area image together with an image of the anterior segment of the subject's eye E (or a schematic diagram of the anterior segment, etc.), the same processing as in the case of the image of the fundus oculi Ef can be applied.

As a typical example of displaying the opacity area image together with the OCT image of the subject's eye E, the opacity area image can be displayed together with the OCT image of the anterior segment. This OCT image is obtained, for example, by applying an OCT scan to the three-dimensional region of the anterior segment using the ophthalmologic apparatus 1 .

FIG. 10A shows an exemplary display mode when an opacity region image is displayed together with an OCT image of the anterior segment. In this example, the display control unit 2102 causes the display unit 241 to display a B-scan image (longitudinal cross-sectional image) 600 of the anterior segment of the subject's eye E and an opacity region image 610 . As a result, it becomes possible to easily grasp the location (distribution) of turbidity in the anterior segment (in particular, the crystalline lens).

By rendering (MPR or the like) the three-dimensional OCT data, a B-scan image of a desired cross section can be constructed, and an opacity region image can be displayed together with this B-scan image. It is also possible to construct an MPR image representing an arbitrary cross section such as a cross section or an oblique section, and display the turbidity region image together with this MPR image. It is also possible to display a cloudy area image together with an image obtained by applying an arbitrary rendering method such as volume rendering.

FIG. 10B shows another example of a display mode when an opacity region image is displayed together with an OCT image of the anterior segment. In this example, the display control unit 2102 causes the display unit 241 to display an OCT front image (projection image or the like) 700 of the anterior segment of the subject's eye E and a cloudy area image 710 . As a result, it becomes possible to easily grasp the opacity site (distribution) in the anterior segment. It should be noted that the same display mode can be applied when displaying the opacity region image together with the anterior segment image acquired by the anterior segment camera 300 or the like.

Even when displaying the opacity area image together with the front image of the anterior segment in this way, it is possible to perform the same registration as when displaying the image of the fundus oculi Ef.

As described in the modification above, when specifying a region (target region) suitable for imaging or measurement performed by projecting light onto the fundus oculi Ef by the data acquisition unit 250, the procedure is the same as for displaying the opacity region image. Then, an image representing the target region (target region image) can be displayed on the display unit 241 . Furthermore, the display control unit 2102 can display the target area image together with the image of the subject's eye E acquired in advance. As in the case of displaying together with the opacity region image, the image of the subject's eye E displayed together with the target region image may be any image.

<effect>
Effects of some exemplary embodiments will be described.

The ophthalmic device (1) according to the first exemplary embodiment includes an OCT section (such as a data acquisition section 250) and a data processing section (230). The OCT unit applies an optical coherence tomography (OCT) scan to a three-dimensional region of the anterior segment of the subject's eye to collect OCT data. The data processing unit analyzes the OCT data to identify the opacified region of the anterior segment.

According to such an ophthalmologic apparatus (1), it is possible to obtain information indicating the opacity state in the subject's eye from data obtained by three-dimensional OCT scanning of the anterior segment. Therefore, it is possible to grasp the opacity state in the subject's eye by a new method different from the conventional transillumination method.

The ophthalmologic apparatus (1) according to the first exemplary embodiment includes a display control unit (2102) that causes display means (display unit 241) to display an image representing an opacity region specified by a data processing unit (230). It may further contain In addition, the display control unit (2102) can display an image representing the opacity region together with the image of the subject's eye obtained in advance. This image of the subject's eye may be an image of the fundus. Also, the image of the subject's eye may be an OCT image. This OCT image may include a longitudinal cross-sectional image of the anterior segment acquired by the OCT section, or may include a frontal image of the anterior segment acquired by the OCT section.

According to such an ophthalmologic apparatus (1), it is possible to easily grasp the opacity site in the anterior segment of the subject's eye.

The ophthalmologic apparatus (1) according to the first exemplary embodiment includes a data acquisition unit (250) that projects light (measurement light LS) onto the fundus of an eye to be inspected and acquires data of the eye to be inspected based on the returned light. may further include

According to such an ophthalmologic apparatus (1), measurement and photography can be performed by projecting light onto the fundus of the eye, and turbidity that interferes with the measurement and photography can be specified.

In a first exemplary embodiment, the data acquisition unit (250) may include data acquisition optics that project light onto the fundus and detect the returned light. The data acquisition optical system in the above embodiment includes a group of elements forming a measurement arm provided in the retinal camera unit 2 and a group of elements provided in the OCT unit 100 . Furthermore, the ophthalmologic apparatus (1) according to the first exemplary embodiment includes a movement mechanism (150), a display control section (2102), an operation section (242), and a drive control section (2101). can be A moving mechanism moves the data acquisition optical system. The display control unit causes the display means (display unit 241) to display an image representing the opacity region specified by the data processing unit. The operation unit is used to perform alignment operations for the data acquisition optical system. The drive control section controls the moving mechanism based on a signal from the operation section.

According to such an ophthalmologic apparatus (1), it is possible to perform manual alignment while referring to the opacity state in the subject's eye obtained by a novel method.

In a first exemplary embodiment, the data acquisition unit (250) may include data acquisition optics that project light onto the fundus and detect the returned light. Furthermore, the ophthalmic device (1) according to the first exemplary embodiment may include a movement mechanism (150) and a drive controller (2101). A moving mechanism moves the data acquisition optical system. The drive control unit controls the moving mechanism. Additionally, the data processor (230) may include a movement target determiner (234) that determines a movement target for the data acquisition optics based on the opacity region. The drive control section controls the movement mechanism based on this movement target.

According to such an ophthalmologic apparatus (1), it is possible to perform auto-alignment based on the opacity state in the subject's eye obtained by a novel method.

The ophthalmic apparatus according to the second exemplary embodiment includes a data acquisition unit (250), an OCT unit (such as data acquisition unit 250), and a data processing unit (230A). The data acquisition unit projects light (measurement light LS) onto the fundus of the eye to be inspected and acquires data of the eye to be inspected based on the returned light. The OCT unit applies an optical coherence tomography (OCT) scan to a three-dimensional region of the anterior segment of the subject's eye to collect OCT data. The data processing unit analyzes the OCT data and identifies a target region for projecting light onto the fundus by the data acquisition unit.

According to such an ophthalmologic apparatus, it is possible to obtain a target region for applying imaging or measurement by the data acquisition unit from data obtained by three-dimensional OCT scanning of the anterior segment. Therefore, it is possible to grasp a suitable area for photographing or measurement by a new method different from the conventional transillumination method.

In a second exemplary embodiment, the data acquisition unit (250) may include data acquisition optics that project light onto the fundus and detect the returned light. Furthermore, the ophthalmologic apparatus according to the second exemplary embodiment may include a movement mechanism (150), a display control section (2102), an operation section (242), and a drive control section (2101). . A moving mechanism moves the data acquisition optical system. The display control unit causes the display means (display unit 241) to display an image representing the target area specified by the data processing unit. The operation section is used to perform alignment operations of the data acquisition optical system. The drive control section controls the moving mechanism based on a signal from the operation section.

According to such an ophthalmologic apparatus, it is possible to perform manual alignment while referring to a region suitable for imaging or measurement acquired by a new technique.

In a second exemplary embodiment, the data acquisition unit (250) may include data acquisition optics that project light onto the fundus and detect the returned light. Furthermore, the ophthalmic device according to the second exemplary embodiment may include a movement mechanism (150) and a drive controller (2101). A moving mechanism moves the data acquisition optical system. The drive control unit controls the moving mechanism. Additionally, the data processor (230) may include a movement target determiner (234) that determines a movement target for the data acquisition optics based on the region of interest. The drive control section controls the movement mechanism based on this movement target.

According to such an ophthalmologic apparatus, it is possible to perform auto-alignment based on a region suitable for imaging or measurement acquired by a new technique.

The ophthalmologic apparatus according to the second exemplary embodiment further includes a display control unit (2102) that causes the display means (display unit 241) to display an image representing the target region specified by the data processing unit (230). you can stay In addition, the display control unit (2102) can display an image representing the target region together with the image of the subject's eye obtained in advance. This image of the subject's eye may be an image of the fundus. Also, the image of the subject's eye may be an OCT image. This OCT image may include a longitudinal cross-sectional image of the anterior segment acquired by the OCT section, or may include a frontal image of the anterior segment acquired by the OCT section.

According to such an ophthalmologic apparatus, it is possible to easily grasp a suitable area for projecting light onto the fundus by the data acquisition unit.

In the first or second exemplary embodiment, the data acquisition unit (250) may be configured to apply an OCT scan to the fundus to acquire data of the subject eye. In this case, the ophthalmologic apparatus includes, for example, a lens unit (anterior segment OCT attachment 400) for switching the site to which OCT is applied. In order to switch the site to which OCT is applied, for example, it is possible to adopt a configuration including a lens that can move along the optical path or a configuration including a lens that can be inserted into and removed from the optical path. be.

In the first or second exemplary embodiments, the data acquisition section and the OCT section may include common scanning optics. In the above embodiment, the common scanning optical system includes the group of elements that constitute the measurement arm provided in the retinal camera unit 2 and the group of elements provided in the OCT unit 100 .

According to such a configuration, it is possible to simplify the optical configuration when both the data acquisition section and the OCT section can perform optical scanning.

In the first or second exemplary embodiments, the data acquisition section may include a data acquisition optical system that projects light onto the fundus and detects the returned light. Furthermore, the ophthalmic apparatus according to the first or second exemplary embodiment further includes an alignment system (260) for auto-aligning the data acquisition optics. After auto-alignment, the data acquisition unit projects light toward the fundus and acquires data of the subject's eye based on the returned light. The data processing section includes a determination section (232). The determination unit determines whether or not to perform an OCT scan by the OCT unit based on the data acquired by the data acquisition unit after auto-alignment.

With such a configuration, a 3-dimensional OCT scan is applied to the anterior segment to determine opacified or target regions only when auto-alignment fails to produce satisfactory results. Therefore, it is possible to improve the efficiency of the processing and shorten the inspection time.

The embodiments described above are merely examples of implementations of the invention. A person who intends to implement this invention can make arbitrary modifications (omission, substitution, addition, etc.) within the scope of the gist of this invention.

1 ophthalmologic apparatus 150 moving mechanism 210 control unit 2101 drive control unit 2102 display control unit 230, 230A data processing unit 231 position information acquisition unit 232 determination unit 233 opacity area identification unit 234 movement target determination unit 235 target area identification unit 241 display unit 242 Operation unit 250 Data acquisition unit 260 Alignment system 300 Anterior segment camera E Eye to be examined Ef Fundus

Claims (1)

a data acquisition unit that projects light onto the fundus of an eye to be inspected and acquires data of the eye to be inspected based on the returned light;
an OCT unit that collects OCT data by applying an optical coherence tomography (OCT) scan to a three-dimensional region of the anterior segment of the eye to be examined;
a data processing unit that analyzes the OCT data and specifies a target area for projecting the light onto the fundus by the data acquisition unit ;
the data acquisition unit includes a data acquisition optical system that projects the light onto the fundus and detects the return light;
further comprising an alignment system for auto-aligning the data acquisition optical system;
After the auto-alignment, the data acquisition unit projects light toward the fundus and acquires data of the eye to be examined based on the returned light,
The data processing unit determines whether or not to perform the optical coherence tomography (OCT) scan by the OCT unit based on the data of the subject eye acquired by the data acquiring unit after the auto-alignment. including decision part
An ophthalmic device characterized by:

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