JP6959158B2 - Ophthalmic equipment - Google Patents

Description

The present invention relates to an ophthalmic apparatus.

In the field of ophthalmology, a device for obtaining an image of an eye to be inspected (ophthalmology imaging device) and a device for measuring the characteristics of the eye to be inspected (ophthalmology measuring device) are used in medical treatment.

Examples of ophthalmologic imaging devices include an optical coherence tomography that obtains data using optical coherence tomography (OCT), a fundus camera that photographs the fundus, and a fundus image by laser scanning using a confocal optical system. There are scanning laser ophthalmoscopes (SLO) and the like.

Examples of ophthalmic measuring devices include an ocular refraction tester (refractometer) that measures the refraction characteristics of the eye to be inspected, a wavefront analyzer that obtains aberration data of the eye to be inspected using a Hartmann-Shack sensor, and the like.

The ophthalmic apparatus illustrated above projects light toward the fundus of the eye to be inspected and obtains data based on the return light. Therefore, when the intermediate translucent body (lens, vitreous, etc.) is opaque, such as in a cataract eye, the projected light and the return light are affected by the opacity, and imaging and measurement may not be suitable.

The transillumination method is known as a method for grasping the turbidity of the intermediate translucent body. The transillumination method is a method of projecting illumination light on the fundus and observing the pupil region illuminated from the inside of the eye to be inspected by the reflection. In the transilluminated image obtained by this, the turbid part is projected as a shadow. When an error occurs in photography or measurement, alignment is performed by referring to the transillumination image so as to avoid opaque areas, that is, the position of light incident on the eye to be inspected.

In general, in the transillumination method, it is desirable to secure a sufficient amount of fundus reflection to obtain a high-quality transillumination image. On the other hand, in consideration of the safety of the eye to be inspected, the amount of light incident on the eye to be inspected is limited. In order to achieve both of these two conditions, it is required to efficiently utilize the amount of illumination light to ensure the brightness of the fundus reflection.

In order to satisfy this requirement, it is conceivable to inject illumination light through the apex of the cornea. When the conventional transillumination method is applied by applying this method, the corneal reflection image (bright spot) of the illumination light is mixed in the transillumination image, so it is necessary to confirm whether or not there is turbidity at the position of the corneal reflection image. The problem arises that it cannot be done.

Japanese Patent No. 4469205 Japanese Patent No. 4733511 Japanese Patent No. 5500587 Japanese Patent No. 6143447

An object of the present invention is to provide an improvement of a transillumination method for suitably grasping a turbid portion in an eye to be inspected.

The first aspect of the embodiment is an ophthalmic apparatus for optically acquiring data of an eye to be inspected, a projection system for projecting illumination light for transillumination photography onto the fundus of the eye to be inspected, and the illumination. An anterior segment imaging system that photographs the anterior segment of the eye to be inspected from two or more directions in which light is projected onto the fundus, and a two or more directions that correspond to the two or more directions acquired by the anterior segment imaging system. It includes an image processing unit that analyzes the above image of the anterior segment of the eye and identifies a turbid region corresponding to opacity inside the eye to be inspected.

The second aspect of the embodiment is the ophthalmic apparatus of the first aspect, in which the image processing unit analyzes the two or more anterior eye image images and removes the corneal reflex image caused by the illumination light. A composite image based on the above-mentioned two or more anterior segment images is formed.

The third aspect of the embodiment is the ophthalmic apparatus of the second aspect, in which the image processing unit analyzes the two or more anterior ocular segment images and uses each of the two or more anterior ocular segment images. An image that forms the composite image based on the reflection image removing unit that removes the corneal reflex image caused by the illumination light and the two or more anterior eye part images from which the corneal reflex image is removed by the reflection image removing unit. Including the synthesis part.

A fourth aspect of the embodiment is the ophthalmic apparatus of the third aspect, in which the image processing unit forms a frontal image of the anterior eye portion as the composite image.

A fifth aspect of the embodiment is the ophthalmic apparatus according to any one of the second to fourth aspects, in which the data acquisition optical system for optically acquiring the data and the data acquisition optical system are moved. A drive unit and a drive control unit that controls the drive unit are further included, and the image processing unit includes a first movement target determination unit that determines a movement target of the data acquisition optical system based on the composite image. , The drive control unit controls the drive unit based on the movement target.

A sixth aspect of the embodiment is the ophthalmic apparatus according to any one of the second to fifth aspects, further including a display control unit for displaying the composite image on the display means.

A seventh aspect of the embodiment is the ophthalmic apparatus according to any one of the second to fourth aspects, in which the data acquisition optical system for optically acquiring the data and the data acquisition optical system are moved. A drive unit, a display control unit for displaying the composite image on a display means, an operation unit for performing an alignment operation of the data acquisition optical system, and a drive for controlling the drive unit based on a signal from the operation unit. It further includes a control unit.

The eighth aspect of the embodiment is the ophthalmic apparatus of the seventh aspect, and the image processing unit includes a first movement target determination unit that determines a movement target of the data acquisition optical system based on the composite image. Including, the display control unit causes the display means to display information for the alignment operation based on the movement target.

A ninth aspect of the embodiment is the ophthalmic apparatus of the first aspect, wherein a data acquisition optical system for optically acquiring the data, a drive unit for moving the data acquisition optical system, and the drive. The image processing unit further includes a drive control unit that controls the unit, and the image processing unit analyzes two or more anterior segment images corresponding to the two or more directions acquired by the anterior segment imaging system and analyzes the subject. The drive control unit includes a position information acquisition unit that acquires position information for optometry, the drive control unit applies alignment control based on the position information to the drive unit, and after the alignment control, the projection system emits the illumination light. It is projected onto the fundus of the eye.

A tenth aspect of the embodiment is the ophthalmic apparatus of the first aspect, wherein a data acquisition optical system for optically acquiring the data, a drive unit for moving the data acquisition optical system, and the drive are provided. The image processing unit further includes a drive control unit that controls the unit, the image processing unit includes a second movement target determination unit that determines a movement target of the data acquisition optical system based on the turbid region, and the drive control unit includes a second movement target determination unit. The drive unit is controlled based on the movement target.

The eleventh aspect of the embodiment is the ophthalmic apparatus of the first aspect, in which the image processing unit analyzes the two or more anterior ocular segment images and out of the two or more anterior ocular segment images. The corneal reflex image caused by the illumination light is removed from at least one anterior eye image.

The twelfth aspect of the embodiment is the ophthalmic apparatus according to any one of the first to eleventh aspects, and the projection system projects light for acquiring the data onto the fundus as the illumination light.

A thirteenth aspect of the embodiment is the ophthalmologic apparatus of the twelfth aspect, further comprising an optical scanner for acquiring the data by optical scanning, wherein the projection system is said via the optical scanner. Illumination light is projected onto the fundus.

A fourteenth aspect of the embodiment is the ophthalmologic apparatus of the thirteenth aspect, in which the measurement light is projected onto the fundus of the eye via the optical scanner, and the return light of the measurement light is superimposed on the reference light to cause interference light. The OCT unit further includes an OCT unit that generates the data based on the detection result of the interference light, and the projection system projects the measurement light onto the fundus as the illumination light.

A fifteenth aspect of the embodiment is the ophthalmologic apparatus of the thirteenth or fourteenth aspect, wherein the optical scanner changes the deflection direction of the illumination light with time.

A sixteenth aspect of the embodiment is an ophthalmic apparatus for optically acquiring data of the eye to be inspected, the projection system for projecting illumination light for transillumination photography onto the fundus of the eye to be inspected, and the illumination. An anterior ocular segment imaging system in which the anterior segment of the eye to be inspected, in which light is projected onto the fundus of the eye, is photographed from two or more directions, and a two or more directions acquired by the anterior segment imaging system 2 It includes an image processing unit that analyzes the above-mentioned anterior-eye image and forms a composite image based on the two or more anterior images from which the corneal reflection image caused by the illumination light is removed.

According to the present invention, it is possible to preferably grasp the turbid portion in the eye to be inspected by improving the transillumination method.

It is the schematic which shows an example of the structure of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the ophthalmic apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the ophthalmic apparatus which concerns on embodiment. It is a flowchart which shows an example of the operation which the ophthalmic apparatus which concerns on embodiment can perform. It is a flowchart which shows an example of the operation which the ophthalmic apparatus which concerns on embodiment can perform.

An exemplary embodiment of the ophthalmic apparatus according to the embodiment will be described in detail with reference to the drawings. The ophthalmic apparatus according to the embodiment is used to optically acquire data of the eye to be inspected (that is, using light and using optical technology). In particular, the ophthalmic apparatus according to the embodiment can acquire data of the eye to be inspected by injecting light into the eye through the pupil of the eye to be inspected.

Such an ophthalmic apparatus includes, for example, at least one of an imaging function and a measuring function. Examples of ophthalmic devices having an imaging function include an optical interference tomogram, a fundus camera, and a scanning laser ophthalmoscope. Examples of ophthalmic devices having a measuring function include an ophthalmoflex test device, a wavefront analyzer, a microperimeter, and a perimeter.

In the following examples, an ophthalmologic imaging apparatus in which a swept source OCT and a fundus camera are combined will be described, but the embodiment is not limited thereto. The type of OCT is not limited to swept source OCT, and may be, for example, spectral domain OCT.

The swept source OCT divides the light from the variable wavelength light source (wavelength sweep light source) into the measurement light and the reference light, and superimposes the return light of the measurement light from the test object on the reference light to generate interference light. This is a method in which this interference light is detected by a balanced photodiode or the like, and the detection data collected in response to the sweeping of the wavelength and the scanning of the measurement light is subjected to Fourier transform or the like to form an image.

Spectral domain OCT divides the light from the low coherence light source into measurement light and reference light, and superimposes the return light of the measurement light from the subject with the reference light to generate interference light, and the spectrum of this interference light. This is a method in which the distribution is detected by a spectroscope and the detected spectral distribution is subjected to Fourier transform or the like to form an image.

As described above, the swept source OCT is an OCT method for acquiring the spectral distribution by time division, and the spectral domain OCT is an OCT method for acquiring the spectral distribution by spatial division. The OCT method that can be used in the embodiment is not limited to these, and it is also possible to adopt an embodiment that uses an arbitrary OCT method (for example, time domain OCT) different from these.

In the present specification, unless otherwise specified, "image data" and "image" based on the "image data" are not distinguished. In addition, unless otherwise specified, the site or tissue of the eye to be inspected is not distinguished from the image showing it.

<composition>
The exemplary ophthalmic apparatus 1 shown in FIG. 1 includes a fundus camera unit 2, an OCT unit 100, and an arithmetic control unit 200. The fundus camera unit 2 is provided with an optical system and mechanism for acquiring a frontal image of the eye E to be inspected, and an optical system and mechanism for executing OCT. The OCT unit 100 is provided with an optical system and a mechanism for executing OCT. The arithmetic control unit 200 includes one or more processors configured to perform various processes (arithmetic, control, etc.). Further, the ophthalmic apparatus 1 includes two anterior eye camera 300 for photographing the anterior eye portion from two directions.

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

Further, the ophthalmic apparatus 1 may include an arbitrary element or an arbitrary unit such as a lens unit (for example, an attachment for anterior ocular segment OCT) for switching a site to which OCT is applied.

In the present specification, the "processor" is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (for example, a SPLD (Simple Program)) It means a circuit such as Programmable Logic Device), FPGA (Field Programmable Gate Array)). The processor realizes the function according to the embodiment by reading and executing a program stored in a storage circuit or a storage device, for example.

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

The fundus camera unit 2 includes an illumination optical system 10 and a photographing optical system 30. The illumination optical system 10 irradiates the eye E to be inspected with illumination light. The photographing optical system 30 detects the return light of the illumination light applied to the eye E to be inspected. The measurement light from the OCT unit 100 is guided to the eye E to be inspected through the optical path in the fundus camera unit 2. The return light of the measurement light projected on the eye E (for example, fundus Ef) is guided to the OCT unit 100 through the same optical path in the fundus camera unit 2.

The 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 focused in the vicinity of the photographing light source 15, reflected by the mirror 16, and 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. Then, the observation illumination light is reflected at the peripheral portion of the perforated mirror 21 (the region around the perforated portion), passes through the dichroic mirror 46, is refracted by the objective lens 22, and illuminates the eye E (fundus Ef) to be inspected. do. The return light of the observation illumination light from the eye E to be inspected is refracted by the objective lens 22, passes through the dichroic mirror 46, passes through the hole formed in the central region of the perforated mirror 21, and passes through the dichroic mirror 55. , It is reflected by the mirror 32 via the photographing focusing lens 31. 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 34. The image sensor 35 detects the return light at a predetermined frame rate. The focus of the photographing optical system 30 is adjusted so as to match the fundus Ef or the anterior eye portion.

The light output from the photographing light source 15 (photographing illumination light) is applied to the fundus Ef through the same path as the observation illumination light. The return light of the photographing illumination light from the eye E to be examined 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, and is reflected by the imaging lens 37. An image is formed on the light receiving surface of the image sensor 38.

The liquid crystal display (LCD) 39 displays a fixation target (fixation target image). A part of the light flux output from the LCD 39 is reflected by the half mirror 33A, reflected by the mirror 32, passes through the photographing focusing lens 31 and the dichroic mirror 55, and passes through the hole portion of the perforated mirror 21. The luminous flux that has passed through the hole of the perforated mirror 21 passes through the dichroic mirror 46, is refracted by the objective lens 22, and is projected onto the fundus Ef. The fixation target is typically used to guide and fix the line of sight. The direction in which the line of sight of the eye E to be examined is guided (and fixed), that is, the direction in which the fixation of the eye E to be examined is promoted is called the fixation position.

The fixation position can be changed by changing the display position of the fixation target image on the screen of the LCD 39. Examples of fixation positions include the fixation position for acquiring an image centered on the macula, the fixation position for acquiring an image centered on the optic nerve head, and the position between the macula and the optic nerve head ( There is a fixation position for acquiring an image centered on the fundus (center of the fundus) and a fixation position for acquiring an image of a portion (peripheral part of the fundus) far away from the macula.

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

The configuration for presenting the fixation target whose fixation position can be changed to the eye E to be inspected 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 and the like) are arranged in a matrix can be adopted instead of the display device. In this case, the fixation position of the eye E to be inspected by the fixation target can be changed by selectively lighting the plurality of light emitting units. As another example, a device having one or more movable light emitting units can generate an 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 inspected. The alignment light output from the light emitting diode (LED) 51 passes through the aperture 52, the aperture 53, and the relay lens 54, is reflected by the dichroic mirror 55, passes through the hole portion of the perforated mirror 21, and passes through the dichroic mirror 46. It is transmitted and projected onto the eye E to be inspected through the objective lens 22. The return light (corneal reflex light, etc.) from the eye E to be inspected for the alignment light is guided to the image sensor 35 through the same path as the return light of the observation illumination light. Manual alignment or auto alignment can be executed based on the received light image (alignment index image).

The focus optical system 60 generates a split index used for focus adjustment with respect to the eye E to be inspected. The focus optical system 60 is moved along the optical path (illumination optical path) of the illumination optical system 10 in conjunction with the movement of the imaging focusing lens 31 along the optical path (photographing optical path) of the photographing optical system 30. The reflection rod 67 is inserted and removed from the illumination optical path. When adjusting the focus, the reflecting surface of the reflecting rod 67 is inclined and arranged in the illumination optical path. The focus light output from the LED 61 passes through the relay lens 62, is separated into two luminous fluxes by the split index plate 63, passes through the two-hole diaphragm 64, is reflected by the mirror 65, and is reflected by the condensing lens 66. Once imaged on the reflecting surface of, it is reflected. Further, the focus light is reflected by the perforated mirror 21 via the relay lens 20, passes through the dichroic mirror 46, and is projected onto the eye E to be inspected via the objective lens 22. The return light (reflected light from the fundus, etc.) of the focus light from the eye E to be inspected is guided to the image sensor 35 through the same path as the return light of the alignment light. Manual focusing or auto focusing can be executed based on the received light image (split index image).

The diopter correction lenses 70 and 71 can be selectively inserted into the photographing optical path between the perforated mirror 21 and the dichroic mirror 55. The diopter correction lens 70 is a plus lens (convex lens) for correcting high-intensity hyperopia. The diopter correction lens 71 is a minus lens (concave lens) for correcting intense myopia.

The dichroic mirror 46 synthesizes a fundus photography optical path and an OCT optical path (measurement arm). The dichroic mirror 46 reflects light in the wavelength band used for OCT and transmits light for fundus photography. The measuring 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 this order from the OCT unit 100 side.

The retroreflector 41 is movable along the optical path of the measurement light LS incident on the retroreflector 41, whereby the length of the measurement arm is changed. The change in the measurement arm length is used, for example, for correcting the optical path length according to the axial length and adjusting the interference state.

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

The OCT focusing lens 43 is moved along the measuring arm to adjust the focus of the measuring arm. The movement of the photographing focusing lens 31, the movement of the focus 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 located at a position optically conjugate with the pupil of the eye E to be inspected. The optical scanner 44 deflects the measurement light LS guided by the measurement arm. The optical scanner 44 is, for example, a galvano scanner capable of two-dimensional scanning. Typically, the optical scanner 44 is a one-dimensional scanner (x-scanner) for deflecting the measurement light in the ± x direction and a one-dimensional scanner (y-scanner) for deflecting the measurement light in the ± y direction. And include. In this case, for example, one of these one-dimensional scanners is arranged at a position optically conjugate with the pupil, or a position optically conjugate with the pupil is arranged between these one-dimensional scanners.

<OCT unit 100>
The exemplary OCT unit 100 shown in FIG. 2 is provided with an optical system for performing a swept source OCT. This optical system includes an interference optical system. This interference optical system divides the light from the variable wavelength light source into the measurement light and the reference light, and superimposes the return light of the measurement light projected on the eye E to be examined and the reference light passing through the reference optical path to cause the interference light. Is generated and this interference light is detected. The data (detection signal) obtained by the detection of 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 wavelength tunable laser that changes the wavelength of emitted light at high speed. The light L0 output from the light source unit 101 is guided by the optical fiber 102 to the polarization controller 103, and its polarization state is adjusted. Further, the optical L0 is guided by the optical fiber 104 to the fiber coupler 105 and divided into the measurement optical LS and the reference optical 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 luminous flux, 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 with the optical path length of the measurement light LS. The dispersion compensating member 113, together with the dispersion compensating member 42 arranged on the measurement arm, acts 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 light LR incident on it, thereby changing the length of the reference arm. The change of the reference arm length is used, for example, for correcting the optical path length according to the axial length and adjusting the interference state.

The reference light LR that has passed through the retroreflector 114 is converted from a parallel luminous flux to a focused luminous flux by the collimator 116 via the dispersion compensating member 113 and the optical path length correction member 112, and is incident on the optical fiber 117. The reference light LR incident on the optical fiber 117 is guided by the polarization controller 118 to adjust its polarization state, is guided to the attenuator 120 through the optical fiber 119 to adjust the amount of light, and is guided to the fiber coupler 122 through the optical fiber 121. Be guided.

On the other hand, the measurement optical 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, and is converted into a parallel light beam, the retroreflector 41, the dispersion compensation member 42, the OCT focusing lens 43, and the optical scanner 44. , And is reflected by the dichroic mirror 46 via the relay lens 45, refracted by the objective lens 22, and projected onto the eye E to be inspected. The measurement light LS is scattered and reflected at various depth positions of the eye E to be inspected. The return light from the eye E to be inspected of the measurement light LS travels in the opposite direction on 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 incidented via the optical fiber 128 and the reference light LR incidented via the optical fiber 121 to generate interference light. The fiber coupler 122 generates a pair of interference light LCs by branching the generated interference light at a predetermined branching ratio (for example, 1: 1). The pair of interference light LCs are guided to the detector 125 through the optical fibers 123 and 124, respectively.

The detector 125 includes, for example, a balanced photodiode. The balanced photodiode includes a pair of photodetectors that detect each pair of interference light LCs, and outputs the difference between the pair of detection signals obtained by these. The detector 125 sends this output (detection signal such as a difference signal) to the data collection system (DAQ) 130.

A clock KC is supplied to the data collection system 130 from the light source unit 101. 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 tunable light source. The light source unit 101, for example, branches the light L0 of each output wavelength to generate two branched lights, optically delays one of the branched lights, synthesizes the branched lights, and produces the obtained combined light. It detects and generates a clock KC based on the detected signal. The data collection system 130 executes sampling of the detection signal (difference signal) input from the detector 125 based on the clock KC. The data collection system 130 sends the data obtained by this sampling to the arithmetic control unit 200.

In this example, both an element for changing the measurement arm length (for example, the retroreflector 41) and an element for changing the reference arm length (for example, the retroreflector 114 or the reference mirror) are provided. However, only one of these elements may be provided. Further, 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 any element (optical member, mechanism, etc.) can be adopted. ..

<Operation control unit 200>
The arithmetic control unit 200 controls each part of the ophthalmic apparatus 1. In addition, the arithmetic control unit 200 executes various arithmetic processes. For example, the arithmetic control unit 200 performs signal processing such as Fourier transform on the spectral distribution based on the sampling data group obtained by the data collection system 130 for each series of wavelength scans (for each A line). Form a reflection intensity profile in the line. Further, the arithmetic control unit 200 forms image data by imaging the reflection intensity profile of each A line. The arithmetic processing for that purpose is the same as that of the conventional swept source OCT.

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

<User interface 240>
The user interface 240 includes a display unit 241 and an operation unit 242. The display unit 241 includes a 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 in which a display function and an operation function are integrated. It is also possible to build embodiments that do not include at least part of the user interface 240. For example, the display device may be an external device connected to the ophthalmologic imaging device.

<Front eye camera 300>
The anterior segment camera 300 captures the anterior segment of the eye E to be inspected from two or more different directions. The front eye camera 300 includes an image sensor such as a CCD image sensor or a CMOS image sensor. In this embodiment, two anterior eye cameras 300 are provided on the surface of the fundus camera unit 2 on the subject side (see the anterior eye cameras 300A and 300B shown in FIG. 4A). As shown in FIGS. 1 and 4A, the front eye cameras 300A and 300B are provided at positions deviating from the optical path passing through the objective lens 22. Hereinafter, one or both of the anterior eye cameras 300A and 300B may be indicated by reference numeral 300.

In this embodiment, two anterior eye cameras 300A and 300B are provided, but typically, the number of anterior eye cameras may be any number of 2 or more. Considering the arithmetic processing described later, it is sufficient (but not limited to) a configuration in which the anterior segment can be photographed from two different directions. Further, one or more movable front eye cameras 300 may be provided.

In this embodiment, the anterior segment camera 300 is provided separately from the illumination optical system 10 and the photographing optical system 30, but at least the anterior segment imaging can be performed using the photographing optical system 30. That is, one of the two or more front eye cameras may include the photographing 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.

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

Two or more anterior segment cameras can image the anterior segment from two or more different directions substantially simultaneously. "Substantially at the same time" means that, in addition to the case where the shooting timings by two or more anterior eye cameras are simultaneous, for example, the case where there is a difference in shooting timing to the extent that eye movements can be ignored is allowed. show. Thereby, an image when the eye E to be inspected is in substantially the same position and orientation can be acquired by two or more anterior eye cameras.

Shooting with two or more front eye cameras may be moving image shooting or still image shooting. In the case of moving image shooting, it is possible to realize substantially simultaneous front eye shooting as described above by controlling the shooting start timing to be adjusted and controlling the frame rate and the shooting timing of each frame. .. On the other hand, in the case of still image shooting, this can be realized by controlling the shooting timing to be adjusted.

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

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

<Main control unit 211>
The main control unit 211 includes a processor and controls each element of the ophthalmic apparatus 1 (including the elements shown in FIGS. 1 to 4B). The main control unit 211 is realized by the cooperation between the hardware including the circuit and the 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 focusing drive unit (not shown) under the control of the main control unit 211. The retroreflector 41 provided on the measuring arm is moved by the retroreflector (RR) drive unit 41A under the control of the main control unit 211. The OCT focusing lens 43 arranged on the measuring arm is moved by the OCT focusing driving unit 43A under the control of the main control unit 211. The optical scanner 44 provided on the measuring arm operates under the control of the main control unit 211. The retroreflector 114 arranged on the reference arm is moved by the retroreflector (RR) drive unit 114A under the control of the main control unit 211. Each of these drive units includes an actuator such as a pulse motor that operates under the control of the main control unit 211.

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

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

Aberration information (not shown) is stored in advance in the storage unit 212. In the aberration information, information on the distortion aberration generated in the captured image due to the influence of the optical system mounted on each front eye camera 300 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 information can be said to be a parameter that quantifies the distortion given to the captured image by these optical elements.

An example of a method of generating aberration information will be described. The following measurements are made for each anterior segment camera 300 in consideration of the instrumental error (difference in distortion) of the anterior segment camera 300. The worker prepares a predetermined reference point. The reference point is a photographing target used for detecting distortion. The operator takes a plurality of times while changing the relative position between the reference point and the anterior eye camera 300. As a result, a plurality of captured images of reference points taken from different directions can be obtained. The operator generates aberration information of the anterior eye camera 300 by analyzing the acquired plurality of captured images with a computer. The computer that performs this analysis process may be the data processing unit 230, or any other computer (inspection computer before product shipment, maintenance computer, etc.).

The analysis process for generating aberration information includes, for example, the following steps:
Extraction process to extract the image area corresponding to the reference point from each captured image;
Distribution state calculation process for calculating the distribution state (coordinates) of the image area corresponding to the reference point in each captured image;
Distortion calculation step for calculating parameters representing distortion based on the obtained distribution state;
A correction coefficient calculation step of calculating a coefficient for correcting distortion based on the obtained parameters.

The parameters related to the distortion that the optical system gives to the image include the principal point distance, the principal point position (vertical direction, horizontal direction), and lens distortion (radiation direction, tangential direction). The aberration information is configured as information (for example, table information) in which the identification information of each front eye camera 300 and the corresponding correction coefficient are associated with each other. The aberration information generated in this way is stored in the storage unit 212 by the main control unit 211. The generation of such aberration information and the aberration correction based on the same are called camera calibration and the like.

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

The image forming unit 220 forms the cross-sectional image data based on the data collected by the data collecting system 130. This processing includes signal processing such as noise removal (noise reduction), filtering, and fast Fourier transform (FFT), as in the 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 an area to which an OCT scan is applied. 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 perform voxelization processing on the stack data to construct volume data (voxel data). The stack data and the volume data are typical examples of the three-dimensional image data represented by the three-dimensional coordinate system.

The image forming unit 220 can process three-dimensional image data. For example, the image forming unit 220 can construct new image data by applying rendering to the three-dimensional image data. Rendering methods include volume rendering, maximum value projection (MIP), minimum value projection (MinIP), surface rendering, and multi-section reconstruction (MPR). Further, the image forming unit 220 can construct the projection data by projecting the three-dimensional image data in the z direction (A line direction, depth direction). Further, the image forming unit 220 can construct a shadow gram by projecting a part of the three-dimensional image data in the z direction. A part of the three-dimensional image data projected to construct the shadow gram is set by 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 observation image data or captured image data. The data processing unit 230 includes, for example, at least one of a processor and a dedicated circuit board.

The data acquisition system 250 shown in FIG. 3B is configured to optically acquire the data of the eye to be inspected. The data acquisition system 250 of this example is configured to acquire image data by applying OCT to the eye E to be inspected. The data acquisition system 250 of this example includes an element group that constitutes a measurement arm provided in the fundus camera unit 2, an element group provided in the OCT unit 100, and an image forming unit 220. In another example, the data acquisition system 250 may include a configuration for acquiring a fundus image (illumination optical system 10, photographing optical system 30, etc.).

The projection system 260 shown in FIG. 3B is configured to project illumination light for transillumination photography onto the fundus Ef. The projection system 260 may be configured such that the data acquisition system 250 projects light for acquiring data onto the fundus Ef as illumination light for transillumination imaging.

When the data acquisition system 250 includes an optical scanner 44 for acquiring data by optical scanning, the projection system 260 projects the illumination light for transillumination photography to the fundus Ef via the optical scanner 44. May be configured in. Modality for performing such an optical scan includes OCT and SLO.

In this example, OCT is applied, and the projection system 260 is configured to project the measurement light LS onto the fundus Ef as illumination light for transillumination imaging. When the measurement light LS in the swept source OCT is used as the illumination light for transillumination as in this example, it is not necessary to perform wavelength sweep. For example, the central wavelength of the tunable light source included in the light source unit 101 can be used as illumination light for transillumination photography. Further, it is possible to use the measurement light LS including the wavelength band with high sensitivity of the anterior eye portion photographing system 270 (anterior eye portion camera 300) as the illumination light for the transillumination photographing. On the other hand, when spectral domain OCT is applied, the measurement light which is low coherence light (broadband light) can be used as it is as illumination light for transillumination photography, or a predetermined wavelength included in this measurement light can be selected. It can be extracted by an element (for example, a band pass filter) and used as illumination light for transillumination photography. The OCT measurement light is advantageous for illumination for transillumination photography in that it can project high-intensity light.

When the data acquisition system 250 is configured to acquire data by optical scanning, the optical scanner 44 can change the deflection direction of the illumination light for transillumination photography with time. The control of the optical scanner 44 is executed by the control unit 210. This makes it possible to suppress speckle noise generated in the transillumination image, as in the invention disclosed in Patent Document 3.

The anterior segment imaging system 270 shown in FIG. 3B photographs the anterior segment of the eye E to be inspected from two or more directions when the illumination light for transillumination imaging is projected onto the fundus Ef by the projection system 260. It is configured as follows. The anterior segment imaging system 270 of this example includes the anterior segment cameras 300A and 300B.

The drive unit 280 shown in FIG. 3B is configured to move the optical system (data acquisition optical system) included in the data acquisition system 250. The data acquisition optical system of this example includes a group of elements constituting the measurement arm provided in the fundus camera unit 2. The drive unit 280 of this example includes a moving mechanism 150.

The control unit 210 shown in FIG. 3B includes a drive control unit 2101 and a display control unit 2102. The drive control unit 2101 controls the drive unit 280. The display control unit 2102 controls the user interface 240 (display unit 241).

The configuration of the exemplary data processing unit 230 is shown in FIG. 3B. The data processing unit 230 of this example includes a position information acquisition unit 231, a reflection image removal unit 232, an image composition unit 233, a turbidity region identification unit 234, and a movement target determination unit 235.

<Location information acquisition unit 231>
The position information acquisition unit 231 is configured to analyze two or more anterior eye image images corresponding to two or more directions acquired by the anterior eye imaging system 270 and acquire the position information of the eye E to be inspected. .. The position information acquisition unit 231 analyzes, for example, two anterior eye image acquired by two anterior eye cameras 300 photographing the anterior eye portion of the eye E to be inspected substantially at the same time, and the eye E Find the three-dimensional position of. An example of the process 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 front eye unit camera 300 based on the aberration information stored in the storage unit 212. This correction can be performed, for example, by a known image processing technique based on a correction coefficient for correcting distortion. When the distortion that the optical system of the front eye camera 300 gives to the captured image is sufficiently small, the aberration information and the correction using the aberration information may not be necessary.

Next, the position information acquisition unit 231 can specify an image region (pupil region) corresponding to the pupil of the eye E to be inspected based on the distribution of pixel values (for example, luminance value) of the captured image. Since the pupil is generally expressed with a lower brightness than other parts, it is possible to specify the pupil region by searching the low-brightness 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 specified by searching for a substantially circular and low-luminance image region.

Subsequently, the position information acquisition unit 231 can specify the central position of the specified pupil region. Utilizing the fact that the pupil is substantially circular as described above, the position information acquisition unit 231 may perform, for example, a process of specifying the contour of the pupil region and a process of obtaining an approximate ellipse (or an approximate circle) of the contour. It includes a process of specifying the center position of the approximate ellipse (or approximate circle). The center position of the approximate ellipse (or approximate circle) thus identified is used as the pupil center of the eye E to be inspected. As another example of the process of finding the center of the pupil, the position information acquisition unit 231 can find the center of gravity of the pupil region and set it at the center of the pupil.

The position information acquisition unit 231 is based on the position (and imaging magnification) of the anterior eye camera 300 and the position of the pupil center in the two captured images identified in the previous stage processing, and is based on the position of the pupil center of the eye E to be inspected. The three-dimensional position can be obtained.

FIG. 5A is a top view showing the positional relationship between the eye to be inspected E, the anterior eye camera 300A, and the anterior eye camera 300B. FIG. 5B is a side view showing the positional relationship between the eye to be inspected 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 (imaging distance) between the baselines of the anterior eye cameras 300A and 300B and the pupil center P of the eye E to be inspected is represented by "H". The distance (screen distance) between the front eye camera 300A and its screen plane is represented by "f".

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

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

The position information acquisition unit 231 has, for example, the arrangement relationship shown in FIGS. 5A and 5B with respect to the positions (known) of the front eye cameras 300A and 300B and the positions corresponding to the pupil center P in the two captured images. By applying the known trigonometry in consideration of the above, the three-dimensional position of the pupil center P can be calculated.

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, so that the feature point is three-dimensionally based on the distribution of pixel values of the captured image. It is possible to find the position.

The position information acquired by the position information acquisition unit 231 (for example, information indicating the three-dimensional position of the center of the pupil) is sent to the control unit 210. The drive control unit 2101 applies the alignment control based on this position information to the drive unit 280. This alignment control is an example of the above-mentioned auto alignment. After this auto-alignment, the control unit 210 controls the projection system 260 to project the illumination light for transillumination photography onto the eye E (fundus Ef) to be inspected.

<Reflective image removing unit 232>
As described above, in the conventional technique, when the illumination light for transillumination photography is incident through the corneal apex of the eye E to be inspected, the presence or absence of opacity can be confirmed by the corneal reflection image (bright spot) mixed in the transillumination image. It will be difficult. Therefore, although the amount of illumination light can be efficiently used, it is not possible to apply illumination through the apex of the cornea in transillumination photography.

On the other hand, according to the ophthalmic apparatus 1, even if the illumination light is projected through the apex of the cornea and the transillumination image is taken, the presence or absence of opacity can be confirmed by removing the corneal reflex image from the transillumination image. .. The reflected image removing unit 232 executes a process for removing the corneal reflected image of the illumination light for transillumination photography from the anterior eye portion image.

The incident position of the illumination light for transillumination photography is not limited to the path through the apex of the cornea, and may be any position. For example, if there is an abnormality (eg, opacity or pigmentation) on the pathway through the corneal apex, as in the case of eye E suffering from nuclear cataract, it is possible to apply a pathway off the corneal apex. be.

The reflection image removing unit 232 analyzes two or more anterior eye images acquired by the anterior eye imaging system 270, and from each of these anterior eye images, the cornea caused by the illumination light for transillumination imaging. Remove the reflected image. For example, the reflection image removing unit 232 compares the first anterior segment image and the second anterior segment image of the two or more anterior segment images acquired by the anterior segment imaging system 270 with each other. The corneal reflex image mixed in the first anterior segment image can be removed.

In this example, the reflection image removing unit 232 analyzes the first anterior eye image acquired by the anterior eye camera 300A and the second anterior image acquired by the anterior eye camera 300B. First, the reflection image removing unit 232 specifies a position (pixel) in the second front eye image corresponding to the position (pixel) of the corneal reflection image in the first front eye image. Further, the reflection image removing unit 232 specifies a position (pixel) in the first front eye image corresponding to the position (pixel) of the corneal reflection image in the second front eye image.
Such identification of the corresponding pixel can be performed, for example, by applying a known trigonometry in consideration of the arrangement state shown in FIGS. 5A and 5B.

Since the anterior segment cameras 300A and 300B are arranged so as to capture the anterior segment from different directions, the second anterior segment image corresponding to the corneal reflex image in the first anterior segment image. There is no corneal reflex image at the position, and there is no corneal reflex image at the position in the first anterior segment image corresponding to the corneal reflex image in the second anterior segment image. In this example, the corneal reflex image exists at a position different from the position in the second anterior segment image corresponding to the corneal reflex image in the first anterior segment image, and the second anterior segment image The arrangement of the anterior segment cameras 300A and 300B can be designed in advance so that the corneal reflex image exists at a position different from the position in the first anterior segment image corresponding to the corneal reflex image inside.

Next, the reflection image removing unit 232 replaces the pixels of the corneal reflection image in the first anterior segment image with the corresponding pixels in the second anterior segment image. Further, the reflection image removing unit 232 replaces the pixels of the corneal reflection image in the second anterior segment image with the corresponding pixels in the first anterior segment image. By such processing, the corneal reflex image is removed from the first anterior segment image, and the removed image region is the image region (not the corneal reflex image) in the corresponding second anterior segment image. ) Can be replaced. Similarly, the corneal reflex image is removed from the second anterior segment image, and the removed image region is replaced with the corresponding image region (not the corneal reflex image) in the first anterior segment image. can do. As a result, two anterior segment images that do not include the corneal reflex image are obtained.

<Image composition unit 233>
The image synthesizing unit 233 forms a composite image based on two or more anterior ocular segment images from which the corneal reflection image has been removed by the reflection image removing unit 232. The composite image may be an image of any aspect that can be constructed based on two or more anterior segment images.

The composite image may be, for example, a front image. The front image is, for example, a two-dimensional image defined by a coordinate system orthogonal to the optical axis of the optical system (data acquisition optical system) included in the data acquisition system 250. In this example, the front image is, for example, a two-dimensional image defined by an xy coordinate system orthogonal to the optical axis (objective optical axis) of the objective lens 22.

The image synthesizing unit 233 can perform known image processing for synthesizing two or more images. This image processing (image composition) includes, for example, a known viewpoint transformation in consideration of the arrangement state shown in FIGS. 5A and 5B. Alternatively, the image composition may include a known three-dimensional image construction in consideration of the arrangement state shown in FIGS. 5A and 5B, and rendering for constructing a two-dimensional image from the three-dimensional image data constructed thereby. .. This rendering may include, for example, a projection based on 3D image data defined in the xyz coordinate system.

The image synthesizing unit 233 can also synthesize two or more anterior eye part images acquired by the anterior eye part photographing system 270. Further, after removing the corneal reflex image from a part of two or more anterior segment images, one or more anterior segment images from which the corneal reflex image has been removed and one or more anterior eyes from which the corneal reflex image has not been removed. It is also possible to combine with the part image. Such a composite image includes, for example, a corneal reflex image resulting from each front eye image subjected to the composite process.

The reflection image removing unit 232 can remove the corneal reflection image from this composite image. The removal of the corneal reflex image from the composite image can be performed, for example, in the same manner as the removal from the anterior eye image described above.

In this way, the data processing unit 230 including the reflection image removing unit 232 and the image synthesizing unit 233 analyzes two or more anterior eye image acquired by the anterior eye imaging system 270 and performs transillumination imaging. It is configured to form a composite image from which the corneal reflex image caused by the illumination light is removed. The process for forming a composite image from which the corneal reflex image has been removed is not limited to the examples described here, and may include any image processing technique.

The display control unit 2102 can display the composite image formed by the data processing unit 230 on the display unit 241. Further, the display control unit 2102 displays the anterior eye portion image acquired by the anterior eye portion photographing system 270 on the display unit 241 and the anterior eye portion image from which the corneal reflex image is removed by the reflection image removal unit 232. Can be displayed on the display unit 241.

<Muddy area identification part 234>
The turbid region identification unit 234 identifies the opaque region in the anterior eye portion image of the eye E to be inspected. The opaque region is an image region corresponding to the opacity inside the eye E to be inspected. The opaque region corresponds to the opacity of the intermediate translucent body as seen in cataract eyes.

For example, the turbidity region specifying unit 234 can specify the turbidity region based on the distribution of the pixel values (for example, the luminance value) of the front eye portion image. A turbid part is projected as a shadow in a transilluminated image such as an anterior segment image. The turbid region specifying unit 234 identifies pixels whose brightness value is equal to or less than a predetermined threshold value by applying a threshold value processing related to brightness to the front eye portion image. The pixel group specified by this is set in the turbid region. In this threshold processing, for example, a threshold set by default or a threshold set according to the image of the anterior segment of the eye is used.

The turbid region identification unit 234 can specify the opaque region in the anterior eye portion image after the corneal reflection image is removed by the reflection image removal unit 232. Thereby, the opaque region in the anterior ocular segment image can be identified without being affected by the corneal reflex image.

The turbid region identification unit 234 is a composite image that does not include a corneal reflex image (for example, a composite image based on two or more anterior segment images from which the corneal reflex image has been removed, or a composite image after the corneal reflex image has been removed. The turbid region in the image) can be specified. Thereby, the opaque region in the composite image can be specified without being affected by the corneal reflex image.

In this way, by combining the removal of the corneal reflex image and the identification of the opaque region, it is possible to eliminate the adverse effect of the corneal reflex image on the identification of the distribution of the opaque region. More specifically, in the prior art, it was not possible to confirm whether or not turbidity was present at the position of the corneal reflex image, but according to the ophthalmic apparatus 1 according to this embodiment, the corneal reflex image was removed. Since the entire pupil region can be visualized, problems related to the prior art do not occur.

<Movement target determination unit 235>
The movement target determination unit 235 determines the movement target of the optical system (data acquisition optical system) included in the data acquisition system 250 based on the composite image formed by the image composition unit 233. The determined moving target is used for alignment of the data acquisition optical system.

It is assumed that the composite image input to the movement target determination unit 235 does not include the corneal reflex image, and the turbid region in this composite image has already been specified. The movement target determination unit 235 can determine the movement target of the data acquisition optical system so as to pass through a position different from the turbid region in such a composite image. That is, the movement target determination unit 235 can determine the movement target of the data acquisition optical system so that the measurement light LS projected by the data acquisition system 250 is guided while avoiding turbidity in the eye E to be inspected.

The movement target determination unit 235 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 235 can determine the movement target of the data acquisition optical system so that the entire beam cross section of the measurement light LS passes through the unturbid portion.

As described above, in order to reduce the speckle noise mixed in the anterior segment image acquired by the anterior segment imaging system 270, the control unit 210 changes the deflection direction of the measurement light LS with time. The optical scanner 44 can be controlled. In this case, the movement target determination unit 235 can determine the movement target of the data acquisition optical system in consideration of the change in the passing position of the measurement light LS. For example, the movement target determination unit 235 may 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 in the eye E to be inspected does not overlap with the turbid region. can. Typically, since the optical scanner 44 is arranged at a position optically conjugate with the pupil of the eye E to be inspected, the passage of the measurement light LS at a position relatively far from the pupil (for example, the rear surface of the crystalline lens). The movement target of the data acquisition optical system can be determined so that the change range of the position does not overlap with the turbid region. The distance between the pupil and the predetermined location may be, for example, a value obtained by measuring the eye E to be inspected or a value obtained from model eye data.

The movement target determined by the movement target determination unit 235 is, for example, information including at least the x-coordinate and the y-coordinate. The determined movement target is sent to the control unit 210.

When the alignment is automatically corrected, the drive control unit 2101 can control the drive unit 280 based on the movement target. For example, the drive control unit 2101 can control the drive unit 280 so that the data acquisition optical system is moved to a position corresponding to the x-coordinate and the y-coordinate included in the movement target.

When the alignment is manually corrected, the display control unit 2102 can display, for example, the composite image formed by the image synthesis unit 233 on the display unit 241. In addition, the display control unit 2102 can display the alignment index image together with the composite image. The operation unit 242 is used for the user to perform an alignment operation of the data acquisition optical system. The drive control unit 2101 can control the drive unit 280 based on the signal input from the operation unit 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 may display the information for the alignment operation (alignment support information) on the display unit 241 based on the movement target determined by the movement target determination unit 235. can. The alignment support information may include, for example, information indicating a position corresponding to a movement target, which is displayed together with a front image (for example, a composite image) of the anterior eye portion. Alternatively, the alignment support information includes information indicating the operation direction (movement direction) and / or the operation amount (movement amount), such as an arrow image from the current position of the data acquisition optical system to the position corresponding to the movement target. May include. Such alignment support information is generated based on, for example, the x-coordinate and the y-coordinate included in the movement target.

<motion>
An example of the operation of the ophthalmic apparatus 1 according to this embodiment will be described. Hereinafter, the alignment correction operation that can be performed by the ophthalmic apparatus 1 will be described.

<Automatic alignment correction>
FIG. 6 shows an example of an operation for automatically correcting the alignment.

(S1: Start alignment)
First, the alignment of the data acquisition optical system is started. This alignment may be auto alignment or manual alignment.

The auto-alignment can be executed by using, for example, the anterior-eye photography system 270 (anterior-eye camera 300), the position information acquisition unit 231 and the drive control unit 2101 (stereo camera method). Alternatively, auto-alignment can be performed using, for example, an alignment index. The auto-alignment method is not limited to these, and may be any method such as a method using an optical lever or a method using a Purkinje image. Any known method can be applied to manual alignment.

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

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

In the case of manual alignment, for example, the user inputs an alignment completion instruction using the operation unit 242. Alternatively, the ophthalmic apparatus 1 detects that the alignment of the data acquisition optical system with respect to the eye E to be inspected is guided within a predetermined allowable range by manual alignment.

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 inspected may be started.

(S3: Perform transillumination with the anterior segment imaging system to acquire the anterior segment image group)
Upon completing the alignment, the control unit 210 controls the eye E to be inspected for transillumination imaging.

For example, the control unit 210 controls the projection system 260 to project the illumination light for transillumination photography onto the eye E to be inspected. In this example, the measurement light LS for OCT is used as the illumination light for transillumination photography. Since the alignment is completed in step S2, the measurement light LS is projected at or near the center of the pupil of the eye E to be inspected. That is, the measurement light LS is projected at or near the apex of the cornea. As a result, a bright fundus reflex is obtained.

Through-illumination imaging using the fundus reflection by the measurement light LS is performed using the anterior ocular segment imaging system 270 (fundus cameras 300A and 300B). According to this transillumination image, two or more anterior segment images (anterior segment image group) can be obtained as transillumination images.

(S4: Remove the corneal reflex image from each anterior segment image)
The reflected image removing unit 232 analyzes the anterior eye part image group acquired in step S3 and removes the corneal reflex image caused by the illumination light (measured light LS) for transillumination photography from each anterior eye part image. do.

(S5: Combining anterior segment images to form a frontal image)
The image synthesizing unit 233 synthesizes the anterior eye part image group from which the corneal reflex image has been removed in step S4 to form a frontal image of the anterior eye part of the eye E to be inspected.

The display control unit 2102 can display this front image on the display unit 241.

(S6: Identify the turbid area in the front image)
The turbid region specifying unit 234 identifies the turbid region by analyzing the front image formed in step S5.

The display control unit 2102 can display the information indicating the turbid region on the display unit 241 together with the front image.

(S7: Determine the movement target of the data acquisition optical system)
The movement target determination unit 235 determines the movement target of the data acquisition optical system based on the turbid region identified in step S6.

The movement target determination unit 235 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 turbid region. As described above, the beam diameter of the measurement light LS and / or the deflection range of the measurement light LS for reducing speckle noise may be taken into consideration in determining the movement target.

The display control unit 2102 can display the information indicating the movement target on the display unit 241 together with the front image and / or the information indicating the turbid region.

(S8: Move the data acquisition optical system)
The drive control unit 2101 controls the drive unit 280 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 S7.

(S9: Execute OCT)
When the movement of the data acquisition optical system in step S8 is completed, the control unit 210 controls the data acquisition system 250 to execute OCT on the eye E to be inspected. This completes the operation illustrated in FIG.

<Manual alignment correction>
FIG. 7 shows an example of an operation for automatically correcting the alignment.

(S11 to S17)
Steps S11 to S17 are executed in the same manner as in steps S1 to S7 of FIG. 6 (automatic correction), respectively.

(S18: Display front image)
The display control unit 2102 causes the display unit 241 to display the front image formed in step S15. Further, the display control unit 2102 can display the information indicating the turbidity region specified in step S16 on the display unit 241 together with the front image.

(S19: Display alignment support information)
The display control unit 2102 causes the display unit 241 to display the alignment support information based on the movement target determined in step S17 together with the front image (and the information indicating the turbid region).

(S20: User performs alignment operation)
The user performs an operation of correcting the alignment of the data acquisition optical system by using the operation unit 242 while referring to the front image and the alignment support information (and the information indicating the turbid region) displayed on the display unit 241. ..

(S21: Execute OCT)
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 controls the data acquisition system 250 to execute the OCT for the eye E to be inspected. Alternatively, upon the detection of the completion of the alignment correction by the ophthalmic apparatus 1, the control unit 210 controls the data acquisition system 250 to execute the OCT for the eye E to be inspected. This completes the operation illustrated in FIG. 7.

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

In the above embodiment, the alignment is automatically corrected by using the composite image based on two or more frontal eye images, but the alignment is automatically corrected without forming the composite image. It is also possible to apply the form.

For example, the opaque region identification unit 234 analyzes each anterior eye image acquired by the anterior eye imaging system 270 (anterior eye camera 300) to identify an opaque region in each anterior image. The movement target determination unit 235 moves the data acquisition optical system based on the turbid region specified for each anterior eye image, for example, by applying a known trigonometry considering the arrangement states shown in FIGS. 5A and 5B. You can set goals. Here, the corneal reflex image in each anterior segment image is removed by the same processing as the reflection image removal unit 232, and the movement target is determined based on the opaque region in the anterior segment image group from which the corneal reflex image has been removed. You may try to do it. By controlling the drive unit 280 by the drive control unit 2101 based on the movement target determined in this way, it is possible to realize the automatic correction of the alignment according to the present modification.

<effect>
The effect of this embodiment will be described.

The ophthalmic apparatus (1) according to this embodiment is an apparatus for optically acquiring data of the eye to be inspected (E), and includes a projection system (260), an anterior ocular segment imaging system (270), and image processing. A unit (data processing unit 230) is included. The data of the eye to be inspected optically acquired by the ophthalmic apparatus (1) may be, for example, image data or characteristic measurement data.

The projection system (260) projects illumination light for transillumination photography onto the fundus (Ef) of the eye to be inspected (E). In the above exemplary embodiment, the illumination light for transillumination may be the measurement light LS for OCT.

The anterior segment imaging system (270) photographs the anterior segment of the eye to be inspected (E) from two or more directions in which illumination light for transillumination imaging is projected onto the fundus (Ef). In the above exemplary embodiment, the anterior segment imaging system (270) includes two anterior eye cameras 300A and 300B located at different positions from each other, imaging the anterior segment substantially simultaneously and two fronts. An eye image can be obtained.

The image processing unit (data processing unit 230, turbid region identification unit 234) analyzes two or more anterior eye image images corresponding to two or more directions acquired by the anterior eye imaging system (270), and analyzes the eye to be inspected. The turbidity region corresponding to the turbidity inside (E) is specified. In the above exemplary embodiment, the turbidity region identification can be performed by the turbidity region identification unit 234.

In the ophthalmic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) displays two or more anterior segment images corresponding to two or more directions acquired by the anterior ocular segment imaging system (270). It may be configured to analyze and form a composite image based on two or more anterior eye images from which the corneal reflex image due to the illumination light for transillumination is removed.

In the ophthalmic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) may include a reflection image removing unit (232) and an image synthesizing unit (233). The reflection image removing unit (232) analyzes two or more anterior eye images corresponding to two or more directions acquired by the anterior eye imaging system (270), and illuminates each of these anterior eye images. Remove the corneal reflex image caused by the illumination light for photography. The image compositing unit (233) forms a composite image based on two or more anterior ocular segment images from which the corneal reflex image has been removed by the reflected image removing unit (232).

On the contrary, in the ophthalmic apparatus (1) according to this embodiment, a composite image is formed based on two or more anterior ocular segment images from which the corneal reflex image has not been removed, and the corneal reflex image is removed from the composite image. You may.

In the ophthalmic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) forms two or more front eye image images corresponding to two or more directions acquired by the anterior eye imaging system (270). A frontal image of the anterior segment of the eye may be formed as a composite image based on the image.

According to such an ophthalmic apparatus (1), since the opaque region is specified based on two or more anterior ocular segment images in transillumination imaging, even if the illumination light is incident through the corneal apex, the opacity region is specified. It is possible to remove the corneal reflex image caused by the illumination light. As a result, bright fundus reflection can be ensured by efficiently using the amount of illumination light, and a high-quality transilluminated image can be obtained while ensuring the safety of the eye to be inspected. Therefore, the ophthalmic apparatus (1) provides an improvement in the transillumination method for suitably grasping the opaque portion in the eye to be inspected.

The ophthalmic apparatus (1) according to this embodiment includes a data acquisition optical system (data acquisition system 250), a drive unit (280), and a drive control unit (2101). The data acquisition optical system (data acquisition system 250) is an optical system for optically acquiring the data of the eye to be inspected (E). The drive unit (280) moves the data acquisition optical system (data acquisition system 250). The drive control unit (2101) controls the drive unit (280). The image processing unit (data processing unit 230) includes a first movement target determination unit (movement target determination unit 235). The first movement target determination unit (movement target determination unit 235) is a data acquisition optical system (data acquisition system) based on a composite image based on two or more front eye image acquired by the anterior eye imaging system (270). 250) Determine the movement target. The drive control unit (2101) controls the drive unit (280) based on the determined movement target.

According to such a configuration, it is possible to automatically correct the alignment by using a composite image based on two or more frontal eye images. That is, it is possible to automatically correct the alignment of the data acquisition optical system so that the data of the eye to be inspected is acquired while avoiding the turbid portion in the eye to be inspected.

The ophthalmic apparatus (1) according to this embodiment may include a display control unit (2102). The display control unit (2102) causes the display means (display unit 241) to display a composite image based on two or more front eye image images acquired by the anterior eye imaging system (270).

According to such a configuration, the user can observe the composite image as a transillumination image and can grasp the opaque portion of the eye to be inspected.

The ophthalmic apparatus (1) according to this embodiment includes a data acquisition optical system (data acquisition system 250), a drive unit (280), a display control unit (2102), an operation unit (242), and a drive control unit (2). 2101) and is included. The data acquisition optical system (data acquisition system 250) is an optical system for optically acquiring the data of the eye to be inspected (E). The drive unit (280) moves the data acquisition optical system (data acquisition system 250). The display control unit (2102) causes the display means (display unit 241) to display a composite image based on two or more front eye image images acquired by the anterior eye imaging system (270). The operation unit (242) is used to perform an alignment operation of the data acquisition optical system (data acquisition system 250). The drive control unit (2101) controls the drive unit (280) based on a signal from the operation unit (242).

According to such a configuration, it is possible to manually correct the alignment by using a composite image based on two or more anterior ocular segment images. That is, it is possible to manually correct the alignment of the data acquisition optical system so that the data of the eye to be inspected is acquired while avoiding the opaque portion in the eye to be inspected.

In the ophthalmic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) includes a first movement target determination unit (movement target determination unit 235). The first movement target determination unit (movement target determination unit 235) is a data acquisition optical system (data acquisition system) based on a composite image based on two or more front eye image acquired by the anterior eye imaging system (270). 250) Determine the movement target. The display control unit (2102) causes the display means (display unit 241) to display information (alignment support information) for the alignment operation based on the determined movement target.

With such a configuration, it is possible to facilitate manual correction of the alignment of the data acquisition optical system.

The ophthalmic apparatus (1) according to this embodiment includes a data acquisition optical system (data acquisition system 250), a drive unit (280), and a drive control unit (2101). The data acquisition optical system (data acquisition system 250) is an optical system for optically acquiring the data of the eye to be inspected (E). The drive unit (280) moves the data acquisition optical system (data acquisition system 250). The drive control unit (2101) controls the drive unit (280). The image processing unit (data processing unit 230) includes a position information acquisition unit (231). The position information acquisition unit (231) analyzes two or more anterior segment images corresponding to the two or more directions acquired by the anterior eye imaging system (270) to acquire the position information of the eye to be inspected (E). .. The drive control unit (2101) applies the alignment control based on the acquired position information to the drive unit (280). After this alignment control, the projection system (260) projects the illumination light for transillumination to the fundus (Ef).

According to such a configuration, it is possible to perform alignment correction using illumination light for transillumination photography after aligning the data acquisition optical system by auto-alignment of the stereo camera method.

The ophthalmic apparatus (1) according to this embodiment includes a data acquisition optical system (data acquisition system 250), a drive unit (280), and a drive control unit (2101). The data acquisition optical system (data acquisition system 250) is an optical system for optically acquiring the data of the eye to be inspected (E). The drive unit (280) moves the data acquisition optical system (data acquisition system 250). The drive control unit (2101) controls the drive unit (280). The image processing unit (data processing unit 230) includes a second movement target determination unit (movement target determination unit 235). The second moving target determination unit (moving target determination unit 235) is a data acquisition optical system (data acquisition system 250) based on the turbid region specified by the image processing unit (data processing unit 230, turbid region identification unit 234). Determine the movement target. The drive control unit (2101) controls the drive unit (280) based on the determined movement target.

According to such a configuration, it is possible to automatically correct the alignment without forming a composite image. That is, it is possible to automatically correct the alignment of the data acquisition optical system so that the data of the eye to be inspected is acquired while avoiding the turbid portion in the eye to be inspected.

In the ophthalmic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) analyzes two or more anterior segment images acquired by the anterior segment imaging system (270), and these anterior eyes The corneal reflex image caused by the illumination light for transillumination may be removed from at least one anterior eye image of the part image.

According to such a configuration, when the illumination light for transillumination photography is incident through the apex of the cornea, the anterior segment image (transillumination image) in which the corneal reflection image caused by the projected light is removed is obtained. It is possible to obtain.

In the ophthalmic apparatus (1) according to this embodiment, the projection system (260) projects light for acquiring data of the eye to be inspected (E) onto the fundus (Ef) as illumination light for transillumination. May be good.

The ophthalmic apparatus (1) according to this embodiment may include an optical scanner (44) for acquiring data of the eye to be inspected (E) by an optical scan. Further, the projection system (260) may project the illumination light for transillumination photography onto the fundus (Ef) via the optical scanner (44).

The ophthalmic apparatus (1) according to this embodiment may include an OCT unit (data acquisition system 250). The OCT unit projects the measurement light (LS) onto the fundus (Ef) via the optical scanner (44), superimposes the return light of the measurement light (LS) on the reference light (LR), and emits the interference light (LC). Generate and generate data based on the detection result of interference light (LC). The projection system (260) projects measurement light (LS) onto the fundus (Ef) as illumination light for transillumination imaging.

In the ophthalmic apparatus (1) according to this embodiment, the optical scanner (44) can reduce speckle noise by changing the deflection direction of the illumination light for transillumination photography with time. be.

Another aspect of this embodiment is an ophthalmic apparatus (1) for optically acquiring data of the eye to be inspected (E), which includes a projection system (260), an anterior ocular segment imaging system (270), and the like. It includes an image processing unit (data processing unit 230). The projection system (260) projects illumination light for transillumination photography onto the fundus (Ef) of the eye to be inspected (E). The anterior segment imaging system (270) photographs the anterior segment of the eye to be inspected from two or more directions, in which illumination light for transillumination imaging is projected onto the fundus (Ef). The image processing unit (data processing unit 230) analyzes two or more anterior eye image images corresponding to two or more directions acquired by the anterior eye imaging system (270), and illuminates light for transillumination photography. A composite image is formed based on two or more anterior ocular images from which the corneal reflex image caused by the above is removed.

According to such an ophthalmic apparatus (1), it is possible to acquire a composite image from which the corneal reflex image has been removed even if the illumination light is incident through the corneal apex in the transillumination imaging. Thereby, an improvement of the transillumination method for preferably grasping the turbid part in the eye to be inspected is provided.

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

1 Ophthalmology device 210 Control unit 2101 Drive control unit 2102 Display control unit 230 Data processing unit 231 Position information acquisition unit 232 Reflection image removal unit 233 Image synthesis unit 234 Turbidity area identification unit 235 Movement target determination unit 240 User interface 250 Data acquisition system 260 Projection system 270 Anterior eye imaging system 280 Drive unit E Eye to be inspected Ef Fundus

Claims (16)

It is an ophthalmic device for optically acquiring data of the eye to be inspected.
A projection system that projects illumination light for transillumination photography onto the fundus of the eye to be inspected.
An anterior segment imaging system that photographs the anterior segment of the eye to be inspected from two or more directions in which the illumination light is projected onto the fundus.
An image processing unit that analyzes two or more anterior segment images corresponding to the two or more directions acquired by the anterior eye imaging system and identifies an opacity region corresponding to opacity inside the eye to be inspected.
Ophthalmic equipment including. The image processing unit analyzes the two or more anterior segment images to form a composite image based on the two or more anterior segment images from which the corneal reflex image caused by the illumination light is removed.
The ophthalmic apparatus according to claim 1. The image processing unit
A reflection image removing unit that analyzes the two or more anterior segment images and removes a corneal reflex image caused by the illumination light from each of the two or more anterior segment images.
An image compositing unit that forms the composite image based on the two or more anterior ocular segment images from which the corneal reflex image has been removed by the reflection image removing unit.
including,
The ophthalmic apparatus according to claim 2. The image processing unit forms a frontal image of the anterior eye portion as the composite image.
The ophthalmic apparatus according to claim 3. A data acquisition optical system for optically acquiring the data, and
A drive unit that moves the data acquisition optical system and
A drive control unit that controls the drive unit and
Including
The image processing unit includes a first movement target determination unit that determines a movement target of the data acquisition optical system based on the composite image.
The drive control unit controls the drive unit based on the movement target.
The ophthalmic apparatus according to any one of claims 2 to 4. A display control unit for displaying the composite image on the display means is further included.
The ophthalmic apparatus according to any one of claims 2 to 5. A data acquisition optical system for optically acquiring the data, and
A drive unit that moves the data acquisition optical system and
A display control unit that displays the composite image on the display means,
An operation unit for performing an alignment operation of the data acquisition optical system,
A drive control unit that controls the drive unit based on a signal from the operation unit,
Including,
The ophthalmic apparatus according to any one of claims 2 to 4. The image processing unit includes a first movement target determination unit that determines a movement target of the data acquisition optical system based on the composite image.
The display control unit causes the display means to display information for the alignment operation based on the movement target.
The ophthalmic apparatus according to claim 7. A data acquisition optical system for optically acquiring the data, and
A drive unit that moves the data acquisition optical system and
A drive control unit that controls the drive unit and
Including
The image processing unit includes a position information acquisition unit that analyzes two or more anterior eye image images corresponding to the two or more directions acquired by the anterior eye imaging system and acquires the position information of the eye to be inspected. ,
The drive control unit applies alignment control based on the position information to the drive unit.
After the alignment control, the projection system projects the illumination light onto the fundus.
The ophthalmic apparatus according to claim 1. A data acquisition optical system for optically acquiring the data, and
A drive unit that moves the data acquisition optical system and
Further including a drive control unit that controls the drive unit,
The image processing unit includes a second moving target determining unit that determines a moving target of the data acquisition optical system based on the turbid region.
The drive control unit controls the drive unit based on the movement target.
The ophthalmic apparatus according to claim 1. The image processing unit analyzes the two or more anterior segment images and removes a corneal reflex image caused by the illumination light from at least one anterior segment image of the two or more anterior segment images. ,
The ophthalmic apparatus according to claim 1. The projection system projects light for acquiring the data onto the fundus as the illumination light.
The ophthalmic apparatus according to any one of claims 1 to 11. Further including an optical scanner for acquiring the data by optical scanning,
The projection system projects the illumination light onto the fundus through the optical scanner.
The ophthalmic apparatus according to claim 12. An OCT unit that projects measurement light onto the fundus of the eye via the optical scanner, superimposes the return light of the measurement light on the reference light to generate interference light, and generates the data based on the detection result of the interference light. Including
The projection system projects the measurement light onto the fundus as the illumination light.
13. The ophthalmic apparatus according to claim 13. The optical scanner changes the deflection direction of the illumination light with time.
The ophthalmic apparatus according to claim 13 or 14. It is an ophthalmic device for optically acquiring data of the eye to be inspected.
A projection system that projects illumination light for transillumination photography onto the fundus of the eye to be inspected.
An anterior segment imaging system that photographs the anterior segment of the eye to be inspected from two or more directions in which the illumination light is projected onto the fundus.
The two or more anterior eyes in which the corneal reflex image caused by the illumination light is removed by analyzing two or more anterior eye images corresponding to the two or more directions acquired by the anterior segment imaging system. An image processing unit that forms a composite image based on the part image,
Ophthalmic equipment including.

Images