JP7378557B2 - Ophthalmologic imaging device, its control method, program, and recording medium - Google Patents

Description

The present invention relates to an ophthalmological photographing apparatus, a control method thereof, a program, and a recording medium.

Image diagnosis and image analysis are becoming increasingly important in ophthalmological treatment. In particular, the application of optical coherence tomography (OCT) to ophthalmology is accelerating this trend. OCT enables three-dimensional imaging and three-dimensional structural and functional analysis of the eye to be examined, and is effective for obtaining, for example, the distribution of various measured values.

In recent years, efforts have been made to expand the OCT scan range, that is, to widen the field of view of OCT. For example, in order to scan a wide range from the center to the periphery of the fundus, devices have been developed that expand the deflection angle of optical scanners (galvano mirrors, etc.) and optimize the structure, control, and imaging accordingly. (For example, see Patent Documents 1 and 2).

When an OCT scan (generally a raster scan) is applied to a wide range of the fundus of the eye, the image quality deteriorates particularly in areas away from the center of the fundus (referred to as the peripheral area) due to the influence of aberrations of the ocular optical system. This is due to the fact that the aberration of the eyeball is larger in the periphery than in the center of the fundus (see, for example, Non-Patent Document 1).

In order to eliminate such image quality deterioration, it is possible to perform focus control. However, since the speed of focus control is much slower than the speed of OCT scanning (e.g. A-scan repetition rate), it is not realistic to perform focus control while applying raster scanning to a wide range of the fundus at high speed. do not have.

On the other hand, a scanning type ophthalmologic imaging device (OCT, scanning laser ophthalmoscope (SLO)) that has an aberration correction function is known. For example, the devices disclosed in Patent Documents 3 and 4 are configured to scan the fundus of the eye while measuring aberrations of the eye to be examined.

When such an apparatus performs wide-angle scanning at high speed, the processing load may become extremely large because aberration measurement, aberration amount calculation, and aberration correction control are executed in parallel with scan control. Further, there are also problems in that the hardware and software may become more complicated and costly, and the calculation and control may become more complicated. Furthermore, it is difficult to say that it is practical to perform aberration measurement, aberration amount calculation, and aberration correction control at a speed equivalent to high-speed scanning (and to perform this over a wide range of the posterior eye while synchronizing each other). .

JP2017-086311A JP 2017-047113 Publication Japanese Patent Application Publication No. 2011-104126 Japanese Patent Application Publication No. 2015-221097

JAMES POLANS, 4 others, "Wide-field optical model of the human eye with asymmetrically tilted and decentered lens that reproduces measured ocular aberrations", Optica, February 2015, Vol.2, No.2, p.124-134

One purpose of this invention is to provide a technology that can obtain high-quality images even when optical scanning is applied at high speed to a wide range including the center and peripheral areas of the fundus in the posterior segment of the eye. It's about doing.

The ophthalmologic imaging apparatus according to the first aspect of the exemplary embodiment includes a data collection unit that collects data by scanning with light a scan area including the central part of the fundus and the peripheral part of the fundus in the posterior segment of the subject's eye; a storage unit that stores in advance a map representing a distribution of an aberration correction amount in a specific area that is at least a part of the scan area and includes the peripheral part of the fundus; an aberration correction unit that corrects at least aberrations caused by the eye to be examined; The control unit includes a control unit that performs, in conjunction, control of the data collection unit for scanning a region of the posterior eye segment corresponding to the specific area, and control of the aberration correction unit based on the map.

A second aspect of the exemplary embodiment is the ophthalmological imaging apparatus of the first aspect, wherein the map records an aberration correction amount corresponding to each of a plurality of positions within the specific area. , the control unit controls the data collection unit to scan one of the plurality of positions, and corrects the aberration based on the aberration correction amount corresponding to the one position recorded on the map. control in parallel.

A third aspect of the exemplary embodiment is the ophthalmological imaging apparatus according to the first aspect, wherein the data collection unit includes an optical scanner that deflects light for scanning the posterior segment, and wherein the data acquisition unit includes an optical scanner that deflects light for scanning the posterior segment, and Aberration correction amounts corresponding to each of a plurality of control information for the optical scanner are recorded, and the control unit controls the optical scanner based on one of the plurality of control information. , and control of the aberration correction unit based on the aberration correction amount corresponding to the one control information recorded in the map are executed in parallel.

A fourth aspect of the exemplary embodiment is the ophthalmologic imaging apparatus according to any one of the first to third aspects, wherein the specific area includes at least a peripheral area of the scan area.

A fifth aspect of the exemplary embodiment is the ophthalmologic imaging apparatus according to the fourth aspect, in which the control unit generates a continuous first partial pattern for a central region of the scan area that is different from the peripheral region. Control of the data collection unit according to a scan pattern including a continuous second partial pattern for a peripheral area is performed in conjunction with control of the aberration correction unit based on the map.

A sixth aspect of the exemplary embodiment is the ophthalmological imaging apparatus according to the fifth aspect, wherein the scan pattern includes a curved scan pattern defined by a polar coordinate system having the center of the scan area as the origin. .

A seventh aspect of the exemplary embodiment is the ophthalmological imaging apparatus according to the sixth aspect, wherein the curved scan pattern is a spiral scan pattern extending from the center of the scan area toward the outer edge; A spiral scan pattern from the outer edge toward the center.

An eighth aspect of the exemplary embodiment is the ophthalmologic imaging apparatus according to the sixth or seventh aspect, further comprising an image construction section that constructs an image from the data collected by the data collection section, The construction unit forms an image defined in the polar coordinate system from data collected by a scan applied to the posterior segment according to the curved scan pattern, and generates an image defined in the polar coordinate system. Convert to an image defined in a three-dimensional orthogonal coordinate system.

A ninth aspect of the exemplary embodiment is the ophthalmological photographing apparatus according to any one of the first to eighth aspects, comprising: a photographing section that repeatedly photographs the subject's eye; and a time series of images acquired by the photographing section. further comprising a movement detection unit that analyzes an image to detect movement of the subject's eye, the data collection unit includes an optical scanner that deflects light for scanning the posterior eye segment, and the control unit: The optical scanner is controlled based on the output from the movement detection section while controlling the data collection section and the aberration correction section in a coordinated manner.

A tenth aspect of the exemplary embodiment is the ophthalmological imaging apparatus according to any one of the first to ninth aspects, wherein the storage unit stores two or more maps corresponding to two or more diopter values in advance. The control unit selects a map corresponding to the diopter value of the subject's eye from among the two or more maps, and controls the aberration correction unit based on the selected map.

An eleventh aspect of the exemplary embodiment is the ophthalmological imaging apparatus according to any one of the first to ninth aspects, wherein the data collection unit performs an optical coherence tomography (OCT) scan on the posterior segment of the eye. an OCT image construction section that constructs an OCT image from the OCT data collected by the OCT data collection section; The image forming apparatus further includes a map creation section that creates a map to be stored in the storage section based on the image.

A twelfth aspect of the exemplary embodiment includes a data collection unit that collects data by scanning with light a scan area including a central part of the fundus and a peripheral part of the fundus in the posterior segment of the eye to be examined; A method for controlling an ophthalmological imaging apparatus including an aberration correction unit that corrects aberrations caused by the aberration, the method comprising: a map representing a distribution of an aberration correction amount in a specific area that is at least a part of the scan area and includes the peripheral part of the fundus; a control step of performing in conjunction a preparation step, a control of the data collection unit for scanning a region of the posterior eye segment corresponding to the specific area, and a control of the aberration correction unit based on the map; including.

A thirteenth aspect of the exemplary embodiment is a program that causes a computer to execute the method for controlling an ophthalmologic photographing apparatus according to the twelfth aspect.

A fourteenth aspect of the exemplary embodiment is a computer readable non-transitory recording medium recording the program of the thirteenth aspect.

According to the exemplary embodiment, it is possible to obtain a high-quality image even when optical scanning is applied at high speed to a wide range including the central part of the fundus of the posterior segment of the eye and the peripheral part of the fundus.

1 is a schematic diagram illustrating an example of the configuration of an ophthalmologic imaging apparatus according to an exemplary embodiment. 1 is a schematic diagram illustrating an example of the configuration of an ophthalmologic imaging apparatus according to an exemplary embodiment. 1 is a schematic diagram illustrating an example of the configuration of an ophthalmologic imaging apparatus according to an exemplary embodiment. 1 is a schematic diagram illustrating an example of the configuration of an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of a process executed by an ophthalmologic imaging apparatus according to an exemplary embodiment. 3 is a flowchart illustrating an example of the operation of the ophthalmologic imaging apparatus according to the exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of the operation of the ophthalmologic imaging apparatus according to the exemplary embodiment. FIG. 2 is a schematic diagram for explaining an example of the operation of the ophthalmologic imaging apparatus according to the exemplary embodiment.

An ophthalmologic imaging apparatus, a control method thereof, a program, and a recording medium according to an exemplary embodiment will be described in detail with reference to the drawings. The disclosure contents of the documents cited in this specification and any other known technology can be incorporated into the embodiments. Furthermore, unless otherwise specified, "image data" and "images" based on it are not distinguished. Similarly, unless otherwise specified, a "part" of the eye to be examined and its "image" are not distinguished.

The ophthalmologic imaging apparatus according to the exemplary embodiment is capable of measuring the fundus of a living eye using Fourier domain OCT (eg, swept source OCT). The type of OCT applicable to the embodiments is not limited to swept source OCT, but may be, for example, spectral domain OCT or time domain OCT. Further, the object to which OCT is applied is not limited to the fundus of the eye, but may be any part of the eye such as the anterior segment or the vitreous body.

Exemplary embodiments may be capable of processing images acquired by modalities other than OCT. For example, exemplary embodiments may be capable of processing images acquired by any of a fundus camera, an SLO, a slit lamp microscope, and an ophthalmic surgical microscope. The ophthalmological imaging device according to an exemplary embodiment may include any one of a fundus camera, an SLO, a slit lamp microscope, and an ophthalmic surgery microscope.

Images of a subject's eye that can be processed by example embodiments may include images obtained by analyzing images acquired by any modality. Examples of such analysis images include pseudo-color images (segmented pseudo-color images, etc.), images consisting of only a portion of the original image (segment images, etc.), and images obtained by analyzing OCT images. Examples include images representing tissue thickness distribution (layer thickness map, layer thickness graph, etc.), images representing tissue shape (curvature map, etc.), and images representing lesion distribution (lesion map, etc.).

<composition>
The ophthalmologic imaging apparatus 1 of the exemplary embodiment 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 a mechanism for acquiring a frontal image of the eye to be examined. The OCT unit 100 is provided with an optical system and part of a mechanism for performing OCT. Other parts of the optical system and mechanism for performing OCT are provided in the fundus camera unit 2. Arithmetic control unit 200 includes one or more processors that perform various calculations and controls. In addition to these, optional elements such as members for supporting the subject's face (chin rest, forehead rest, etc.) and lens units for switching the target area of OCT (for example, attachment for anterior segment OCT) or a unit may be provided in the ophthalmologic imaging apparatus 1.

In this specification, "processor" refers to, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (e.g. , SPLD (Simple Programmable Logic Device), CPLD (Complex It means a circuit such as a programmable logic device (programmable logic device) or FPGA (field programmable gate array). The processor realizes the functions according to the embodiment by, for example, reading and executing a program stored in a storage circuit or a storage device.

<Funus camera unit 2>
The fundus camera unit 2 is provided with an optical system for photographing the fundus Ef of the eye E to be examined. The acquired image of the fundus Ef (referred to as a fundus image, fundus photograph, etc.) is a frontal image such as an observation image or a photographed image. Observation images are obtained, for example, by video shooting using near-infrared light, and are used for alignment, focusing, tracking, and the like. The photographed image is, for example, a still image using flash light in the visible region or infrared 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 examined with illumination light. The photographing optical system 30 detects the return light of the illumination light from the eye E to be examined. The measurement light from the OCT unit 100 is guided to the eye E through the optical path within the fundus camera unit 2, and the return light is guided to the OCT unit 100 through the same optical path.

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 condensing lens 13, and passes through the visible cut filter 14 to become near-infrared light. Further, the observation illumination light is once focused near the photographing light source 15, reflected by a mirror 16, and passes through a relay lens system 17, a relay lens 18, an aperture 19, and a relay lens system 20. The observation illumination light is reflected at the periphery of the apertured mirror 21 (the area around the aperture), passes through the dichroic mirror 46, and is refracted by the objective lens 22 to illuminate the eye E (fundus Ef). do. The return light of the observation illumination light from the subject's eye E is refracted by the objective lens 22, passes through the dichroic mirror 46, passes through the hole formed in the center area of the perforated mirror 21, and passes through the dichroic mirror 55. , passes through the photographic focusing lens 31 and is reflected by the mirror 32. Furthermore, this returned light passes through the half mirror 33A, is reflected by the dichroic mirror 33, and is imaged by the imaging lens 34 on the light receiving surface of the image sensor 35. The image sensor 35 detects the returned light at a predetermined frame rate. Note that the focus (focal position) of the photographing optical system 30 is adjusted to match the fundus Ef or the anterior segment of the eye.

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

A liquid crystal display (LCD) 39 displays a fixation target (fixation target image). A portion of the light beam output from the LCD 39 is reflected by the half mirror 33A, then reflected by the mirror 32, passes through the photographic focusing lens 31 and the dichroic mirror 55, and then passes through the hole of the perforated mirror 21. The light beam that has passed through the hole of the perforated mirror 21 is transmitted through the dichroic mirror 46, refracted by the objective lens 22, and projected onto the fundus Ef.

By changing the display position of the fixation target image on the screen of the LCD 39, the fixation position of the eye E by the fixation target can be changed. Examples of fixation positions include a fixation position for acquiring an image centered on the macula, a fixation position for acquiring an image centered on the optic disc, and a position between the macula and the optic disc. There is a fixation position for obtaining a central image, and a fixation position for obtaining an image of a region far away from the macula (periphery of the fundus). A graphical user interface (GUI) or the like may be provided for specifying at least one of such typical fixation positions. Further, a GUI or the like for manually moving the fixation position (the display position of the fixation target) can be provided.

The configuration for presenting a fixation target whose fixation position can be changed to the eye E to be examined is not limited to a display device such as an LCD. For example, a fixation matrix in which a plurality of light emitting parts (such as light emitting diodes) are arranged in a matrix (array) can be used instead of the display device. In this case, by selectively lighting up the plurality of light emitting units, the fixation position of the eye E to be examined based on the fixation target can be changed. As another example, a fixation target whose fixation position can be changed can be generated using one or more movable light emitting units.

The alignment optical system 50 generates an alignment index used for alignment of the optical system with respect to the eye E to be examined. 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 of the perforated mirror 21 , and passes through the dichroic mirror 46 . The light is transmitted through the objective lens 22 and projected onto the eye E to be examined. Return light of the alignment light from the eye E to be examined (corneal reflected light, etc.) 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 performed based on the received light image (alignment index image).

As in the prior art, the alignment index image of this example consists of two bright spot images whose positions change depending on the alignment state. When the relative position between the eye E and the optical system changes in the xy direction, the two bright spot images are integrally displaced in the xy direction. When the relative position between the eye E and the optical system changes in the z direction, the relative position (distance) between the two bright spot images changes. When the distance between the eye E and the optical system in the z direction matches the predetermined working distance, the two bright spot images overlap. When the position of the eye E and the position of the optical system match in the xy direction, two bright spot images are presented within or near a predetermined alignment target. When the distance between the eye E and the optical system in the z direction matches the working distance, and the position of the eye E and the optical system match in the xy direction, the two bright spot images overlap and alignment occurs. presented within the target.

In auto-alignment, the data processing unit 230 detects the positions of two bright spot images, and the main control unit 211 controls the movement mechanism 150, which will be described later, based on the positional relationship between the two bright spot images and the alignment target. . In manual alignment, the main control unit 211 displays two bright spot images on the display unit 241 together with the observation image of the eye E, and the user uses the operation unit 242 while referring to the two displayed bright spot images. to operate the moving mechanism 150.

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

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 severe hyperopia. The diopter correction lens 71 is a minus lens (concave lens) for correcting severe myopia.

The dichroic mirror 46 combines the fundus photographing optical path and the OCT optical path (measuring arm). The dichroic mirror 46 reflects light in a wavelength band used for OCT and transmits light for fundus photography. The measurement arm is provided with, in order from the OCT unit 100 side, a collimator lens unit 40, a retroreflector 41, an aberration correction device 47, a dispersion compensation member 42, an OCT focusing lens 43, an optical scanner 44, and a relay lens 45. .

The retroreflector 41 is movable in the direction of the arrow shown in FIG. 1, thereby changing the length of the measurement arm. Changing the measurement arm length is used, for example, to correct the optical path length according to the axial length or to adjust the interference state.

The dispersion compensation member 42 acts together with a dispersion compensation member 113 (described later) disposed on the reference arm 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 measurement arm to perform focus adjustment of the measurement arm. Movement of the imaging focusing lens 31, movement of the focusing optical system 60, and movement of the OCT focusing lens 43 can be controlled in a coordinated manner.

The optical scanner 44 is arranged at a position that is substantially optically conjugate with the pupil of the eye E to be examined. The optical scanner 44 deflects the measurement light LS guided by the measurement arm. The optical scanner 44 is a galvano scanner capable of two-dimensional scanning, including, for example, a galvano mirror for scanning in the x direction and a galvano mirror for scanning in the y direction.

The aberration correction device 47 is a device for correcting aberrations caused by various objects located on the path of the measurement light LS. This aberration includes not only the aberration caused by the eye E but also the aberration (intrinsic aberration) caused by the elements constituting the measurement arm.

Note that, considering that the intrinsic aberration is substantially constant, an aberration correction device for correcting this may be provided separately from the aberration correction device 47. In addition, when an optical element (group) that can be placed on the measurement arm and retracted from it is provided, like the attachment for anterior ocular segment OCT described above, when using this optical element (group), An aberration correction device corresponding to intrinsic aberrations and an aberration correction device corresponding to intrinsic aberrations when not in use may be provided separately, or a single aberration correction device whose correction state can be switched between when in use and when not in use may be provided. A correction device may also be provided.

In this way, the aberration correction device 47 is used to correct at least the aberration caused by the eye E to be examined. The aberration correction device 47 may be, for example, a deformable mirror or a spatial phase modulator.

As disclosed in Patent Document 3, a deformable mirror includes a film-like mirror having a deformable reflective surface and a plurality of actuators two-dimensionally arranged opposite to the back surface of the reflective surface. include. By selectively driving these actuators, the shape of the reflective surface of the film mirror changes. The driving of each actuator is controlled by the main control section 211.

As also disclosed in Patent Document 3, a spatial phase modulator is typically a reflective modulator that uses a liquid crystal element, and selectively modulates a plurality of two-dimensionally arranged electrodes. By applying a voltage to the liquid crystal molecules, the orientation of the liquid crystal molecules is locally changed. This changes the global refractive index distribution and enables spatial phase modulation. Voltage control for each electrode is performed by the main control section 211.

Devices that can be used as the aberration correction device 47 are not limited to reflective wavefront correction devices such as deformable mirrors and reflective spatial phase modulators, but may also be refractive devices.

As an example of a refractive aberration correction device, there is one disclosed in Re-publication No. 2010/007665 (FIGS. 17 and 18 thereof). This aberration correction device has a transparent electrode divided into multiple areas in which a pattern is formed that is symmetrical to a straight line in the tangential direction (or radial direction), and is used to correct comatic aberration that is symmetrical to this straight line. It will be done.

In addition to these examples, any device such as a liquid lens (for example, the liquid lens disclosed in Japanese Unexamined Patent Publication No. 2009-037711), two relatively rotatable cylinder lenses, and a focus mechanism can be used to correct aberrations. It is possible to apply it as a device 47.

<OCT unit 100>
As illustrated in FIG. 2, the OCT unit 100 is provided with an optical system for applying swept source OCT. This optical system includes an interference optical system. This interference optical system splits the light from the wavelength variable light source (wavelength swept light source) into measurement light and reference light, and overlaps the return light of the measurement light from the eye E with the reference light that has passed through the reference optical path. Together, they generate interference light, and this interference light is detected. The detection result (detection signal) obtained by the interference optical system is a signal representing the spectrum of interference light, and is sent to the arithmetic and control unit 200.

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

The reference light LR is guided to a collimator 111 by an optical fiber 110, converted into a parallel light beam, and guided to a retroreflector 114 via an optical path length correction member 112 and a dispersion compensation member 113. The optical path length correction member 112 acts to match the optical path length of the reference light LR and the optical path length of the measurement light LS. The dispersion compensation member 113 acts together with the dispersion compensation member 42 disposed on the measurement arm to match the dispersion characteristics between the reference light LR and the measurement light LS. The retroreflector 114 is movable along the optical path of the reference light LR incident thereon, thereby changing the length of the reference arm. Changing the reference arm length is used, for example, to correct the optical path length according to the axial length or to adjust the interference state.

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

On the other hand, the measurement light LS generated by the fiber coupler 105 is guided by the optical fiber 127 and converted into a parallel light beam by the collimator lens unit 40, which includes the retroreflector 41, the aberration correction device 47, the dispersion compensation member 42, and the OCT focusing lens. 43, the light passes through the optical scanner 44 and the relay lens 45, is reflected by the dichroic mirror 46, is refracted by the objective lens 22, and is projected onto the eye E to be examined. The measurement light LS is scattered and reflected at various depth positions of the eye E to be examined. The return light of the measurement light LS from the eye E to be examined travels the same path as the outgoing path in the opposite direction, 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 incident on the optical fiber 128 and the reference light LR incident on the optical fiber 121 to generate interference light. The fiber coupler 122 generates a pair of interference lights LC by branching the generated interference lights at a predetermined branching ratio (for example, 1:1). A pair of interference lights LC are guided to a detector 125 through optical fibers 123 and 124, respectively.

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

The data collection system 130 is supplied with a clock KC 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 variable wavelength light source. For example, the light source unit 101 splits the light L0 of each output wavelength to generate two branched lights, optically delays one of these branched lights, combines these branched lights, and generates the resulting composite light. A clock KC is generated based on the detection result. The data acquisition system 130 performs sampling of the detection signal input from the detector 125 based on the clock KC. Data acquisition system 130 sends the results of this sampling to arithmetic and control unit 200 .

In this example, both an element for changing the measurement arm length (for example, retroreflector 41) and an element for changing the reference arm length (for example, retroreflector 114 or reference mirror) are provided. However, only one element may be provided. Moreover, 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 may be any elements (optical members, mechanisms, etc.).

<Control system/processing system>
Examples of the configuration of the control system and processing system of the ophthalmologic imaging apparatus 1 are shown in FIGS. 3 and 4. The control section 210, the image construction section 220, and the data processing section 230 are provided in the arithmetic control unit 200, for example. The ophthalmologic imaging apparatus 1 may include a communication device for performing data communication with an external device. The ophthalmologic imaging device 1 may include a drive device (reader/writer) for performing processing for reading data from a recording medium and processing for writing data on a recording medium.

<Control unit 210>
The control unit 210 executes various controls. Control section 210 includes a main control section 211 and a storage section 212. Further, as shown in FIG. 4, the control section 210 of this embodiment includes a scan control section 213, a focus control section 214, and an aberration correction control section 215.

<Main control unit 211>
The main control unit 211 includes a processor and controls each element of the ophthalmologic imaging apparatus 1 (including the elements shown in FIGS. 1 to 4). The main control unit 211 is realized by cooperation between hardware including a processor and control software.

The main control section 211 can operate the scan control section 213 and the focus control section 214 in a coordinated manner (synchronously). Thereby, OCT scanning and focus adjustment are performed in conjunction (synchronously).

The photographic focus drive unit 31A moves the photographic focus lens 31 disposed in the photographic optical path and the focus optical system 60 disposed in the illumination optical path under the control of the main control unit 211. The retroreflector (RR) driving section 41A moves the retroreflector 41 provided on the measurement arm under the control of the main control section 211. The OCT focusing drive section 43A moves the OCT focusing lens 43 disposed on the measurement arm under the control of the main control section 211 (focus control section 214). The optical scanner 44 provided on the measurement arm operates under the control of the main control section 211 (scan control section 213). The aberration correction device 47 operates under the control of the main control section 211 (the aberration correction control section 215). The retroreflector (RR) driving section 114A moves the retroreflector 114 disposed on the reference arm under the control of the main control section 211. Each of the above-described 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 at least the fundus camera unit 2 three-dimensionally, for example. In a typical example, the moving mechanism 150 includes an x stage that is movable in the ±x direction (horizontal direction), an x moving mechanism that moves the x stage, and a y stage that is movable in the ±y direction (vertical direction). , a y-moving mechanism that moves the y-stage, a z-stage that can move in the ±z direction (depth direction), and a z-moving mechanism that moves the z-stage. Each of these moving mechanisms includes an actuator such as a pulse motor that operates under the control of the main control section 211.

<Storage unit 212>
The storage unit 212 stores various data. The data stored in the storage unit 212 includes OCT images, fundus images, eye information to be examined, control parameters, and the like.

The eye information to be examined includes patient information such as patient ID and name, left eye/right eye identification information, electronic medical record information, and the like.

The control parameters include, for example, parameters used to control OCT scanning (scan control parameters) and parameters used to control focus (focal position) (focus control parameters).

The scan control parameter is a parameter indicating the content of control for the optical scanner 44. Examples of scan control parameters include parameters indicating scan patterns, parameters indicating scan speed, and parameters indicating scan intervals. The scan speed is defined, for example, as the A-scan repetition rate. The scan interval is defined as, for example, the interval between adjacent A scans, that is, the array interval of scan points. The scan pattern will be described later.

The focus control parameter is a parameter indicating the content of control for the OCT focusing drive section 43A. Examples of the focus control parameters include a parameter indicating the focal position of the measurement arm, a parameter indicating the moving speed of the focal position, and a parameter indicating the moving acceleration of the focal position. The parameter indicating the focal position is, for example, a parameter indicating the position of the OCT focusing lens 43. The parameter indicating the moving speed of the focal position is, for example, a parameter indicating the moving speed of the OCT focusing lens 43. The parameter indicating the moving acceleration of the focal position is, for example, a parameter indicating the moving acceleration of the OCT focusing lens 43. The moving speed may or may not be constant. The same applies to movement acceleration.

<Aberration map 219>
The storage unit 212 stores an aberration map 219. The aberration map 219 is used by the aberration correction control unit 215 to control the aberration correction device 47. The aberration map 219 is obtained before applying the OCT scan with aberration correction and is stored in the storage unit 212.

The aberration map 219 defines an aberration correction amount in at least a portion of the OCT scan application area (scan area). The area in which the amount of aberration correction is defined is sometimes called a specific area. The specific area may be the entire scan area or only a portion thereof.

The scan area is an area set in advance, and has, for example, a predetermined shape and a predetermined size. The shape of the scan area is, for example, rectangular or circular, and is typically set according to the scan pattern. A rectangular scan area is employed, for example, when a raster scan (three-dimensional scan) consisting of a plurality of B scans arranged parallel to each other is applied. A circular scan area is employed, for example, when any one of a spiral scan, a concentric scan, and a radial scan in which a plurality of B scans in different directions are arranged at equal angular intervals is applied.

For example, a two-dimensional coordinate system (scan coordinate system) for expressing a scan position is defined in the scan area. The scan position can also be said to be, for example, the application target position of A-scan or the projection target position of measurement light LS. The scan coordinate system may be an xy coordinate system in the xyz coordinate system (three-dimensional coordinate system) shown in FIG. Furthermore, in consideration of the fact that the size of the scan area changes depending on the axial length and diopter of the eye E to be examined, a two-dimensional coordinate system different from the xy coordinate system may be set as the scan coordinate system. Hereinafter, it is assumed that magnification correction based on the eye axis length, etc. is applied, and the scan coordinate system is an xy coordinate system.

When the coordinates of a certain scan position are (x, y), an aberration correction amount W (x, y) is associated with this scan position. The aberration map 219 is a map in which an aberration correction amount W (x, y) is associated with each scan position (x, y) within a specific area. In other words, the aberration map 219 represents the distribution of the amount of aberration correction within the specific area.

In the above example, a two-dimensional coordinate system is used to define the scan position, but the definition of the scan position is not limited to this. For example, parameters related to the optical scanner that deflects the measurement light for OCT scanning can be used to define the scan position. In this embodiment, a parameter indicating the direction of a deflection mirror (galvano mirror) included in the optical scanner 44 or a parameter included in a signal for controlling the optical scanner 44 can be used to define the scan position. be.

In this embodiment, the scan area may be the same as the wide-angle OCT scan application area described below. Note that, considering that the influence of aberrations is large in the peripheral part of the fundus, the aberration correction based on the aberration map 219 becomes more effective as the scan area becomes larger. In other words, the aberration correction of this embodiment is effective in wide-angle OCT scanning.

The specific area is an area in which an aberration correction amount is defined in the scan area, and corresponds to at least a part of the scan area.

If the scan area includes at least a portion of the wide-angle OCT scan application area, the specific area may include at least a portion of the wide-angle OCT scan application area. Typically, the specific area includes at least a portion of a peripheral region (described below) in the wide-angle OCT scan application area, and more typically includes the entire peripheral region. This is to correct large aberrations in the peripheral part of the fundus.

The aberration map 219 is created, for example, according to the aberration distribution in a living eye. The aberration map 219 may include an aberration correction amount distribution obtained from an aberration distribution in a standard eye. Alternatively, the aberration map 219 may include an aberration correction amount distribution obtained from an aberration distribution statistically determined by measurements of a large number of living eyes. The aberration correction amount at each scan position is, for example, an amount that reduces aberrations at the scan position, and typically cancels out the aberrations at the scan position. Note that the ophthalmologic imaging device 1 may be provided with a wavefront measurement function to create an aberration map before performing an OCT scan.

Two or more aberration maps can be prepared and used selectively. For example, prepare two or more aberration maps depending on the diopter, such as an aberration map for myopic eyes, an aberration map for hyperopic eyes, an aberration map for highly myopic eyes, and an aberration map for highly hyperopic eyes, and A corresponding aberration map can be selected.

<Scan control unit 213>
The scan control unit 213 controls the optical scanner 44 based on scan control parameters. The scan control unit 213 may further control the light source unit 101. The details of the processing executed by the scan control unit 213 will be described later. The scan control section 213 is included in the main control section 211. The scan control unit 213 is realized by cooperation between hardware including a processor and scan control software.

<Focus control unit 214>
The focus control section 214 controls the OCT focusing drive section 43A based on the focus control parameters. The details of the process executed by the focus control unit 214 will be described later. The focus control section 214 is included in the main control section 211. The focus control unit 214 is realized by cooperation between hardware including a processor and focus control software.

<Aberration correction control unit 215>
The aberration correction control unit 215 controls the aberration correction device 47 based on the aberration map 219.

The main control section 211 causes at least the aberration correction control section 215 and the scan control section 213 to operate in conjunction with each other. That is, the main control unit 211 controls the operation of the scan control unit 213 for applying an OCT scan to a scan area (for example, a wide-angle OCT scan application area) based on scan control parameters, and the aberration correction device 47 based on an aberration map 219. The operation of the aberration correction control unit 215 for the purpose of

Thereby, it is possible to apply an OCT scan to a region of the fundus Ef corresponding to a specific area, and apply aberration correction according to each scan position within the specific area. In other words, it becomes possible to apply A-scan while appropriately correcting aberrations to each scan position within a specific area. OCT scanning is applied to partial areas other than the specific area in the scan area without applying aberration correction. That is, A scan is applied to each scan position outside the specific area without performing aberration correction.

The main control section 211 may cause the aberration correction control section 215, scan control section 213, and focus control section 214 to operate in conjunction with each other. That is, the main control unit 211 controls the operation of the scan control unit 213 for applying an OCT scan to a scan area (for example, a wide-angle OCT scan application area) based on scan control parameters, and the aberration correction device 47 based on an aberration map 219. The operation of the aberration correction control section 215 for controlling the aberration correction control section 215 can be linked with the operation of the focus control section 214 for controlling the OCT focusing drive section 43A based on the focus control parameters.

This makes it possible to apply OCT scanning to the region of the fundus Ef corresponding to the specific area, while applying aberration correction and focus adjustment according to each scan position within the specific area. In other words, it is possible to apply A-scan while appropriately correcting aberrations and adjusting focus to each scan position within a specific area. For partial areas other than the specific area in the scan area, OCT scanning is applied without applying aberration correction and focus adjustment, or focus adjustment and OCT scanning are applied without applying aberration correction. In other words, A scan is applied to each scan position outside the specific area without at least aberration correction.

When two or more aberration maps are stored in the storage unit 212, the aberration correction control unit 215 controls, for example, the position of the imaging focusing lens 31 (or OCT focusing lens 43) after alignment and focus adjustment, and the diopter. The diopter of the eye E to be examined is determined based on whether or not the correction lenses 70 and 71 are used, and the aberration map corresponding to the diopter of the eye E to be examined can be selected from two or more aberration maps. Alternatively, the aberration correction control unit 215 acquires the diopter of the eye E from the medical information (electronic medical record, etc.) of the examinee, and selects an aberration map corresponding to the diopter of the eye E from among two or more aberration maps. You can choose from. The aberration correction control unit 215 controls the aberration correction device 47 based on an aberration map selected from two or more aberration maps.

<Image construction unit 220>
The image construction unit 220 includes a processor, and forms OCT image data of the fundus Ef based on the signal (sampling data) input from the data acquisition system 130. The OCT image data is, for example, B-scan image data (two-dimensional tomographic image data).

Processing to form OCT image data includes noise removal (noise reduction), filter processing, fast Fourier transform (FFT), etc., similar to conventional Fourier domain OCT. In the case of other types of OCT devices, the image construction unit 220 performs known processing depending on the type.

The image construction unit 220 forms three-dimensional data of the fundus Ef based on the signal input from the data acquisition system 130. This three-dimensional data is three-dimensional image data representing a three-dimensional region (volume) of the fundus Ef. This three-dimensional image data means image data in which pixel positions are defined by a three-dimensional coordinate system. Examples of three-dimensional image data include stack data and volume data.

Stack data is image data obtained by three-dimensionally arranging a plurality of tomographic images obtained along a plurality of scan lines based on the positional relationship of these scan lines. In other words, stack data is an image obtained by expressing multiple tomographic images, which were originally defined by individual two-dimensional coordinate systems, using one three-dimensional coordinate system (that is, embedding them in one three-dimensional space). It is data. Alternatively, stack data is obtained by arranging a plurality of A-scan data obtained respectively for a plurality of two-dimensionally arranged scan points (scan point array) three-dimensionally based on the positional relationship of these scan points. This is the image data that was created.

Volume data is image data whose pixels are voxels arranged three-dimensionally, and is also called voxel data. Volume data is formed by applying interpolation processing, voxelization processing, etc. to stack data.

The image construction unit 220 performs rendering on the three-dimensional image data to form a display image. Examples of applicable rendering methods include volume rendering, surface rendering, maximum intensity projection (MIP), minimum intensity projection (MinIP), and multiplanar reconstruction (MPR).

The image construction unit 220 can form an OCT en-face image based on three-dimensional image data. For example, the image construction unit 220 can construct projection data by projecting three-dimensional image data in the z direction (A-line direction, depth direction). Furthermore, the image construction unit 220 can construct a shadowgram by projecting part of the three-dimensional image data in the z direction.

Partial three-dimensional image data projected to construct a shadowgram is set using, for example, segmentation. Segmentation is a process of identifying partial regions in an image. Typically, segmentation is used to identify an image region corresponding to a predetermined tissue of the fundus Ef. Segmentation is performed by, for example, the image construction unit 220 or the data processing unit 230.

The ophthalmologic imaging device 1 may be capable of performing OCT-angiography. OCT angiography is an imaging technique that constructs images in which retinal blood vessels and choroidal blood vessels are emphasized (for example, see Japanese Patent Publication No. 2015-515894). Generally, the fundus tissue (structure) does not change over time, but the blood flow inside blood vessels changes over time. In OCT angiography, images are generated by emphasizing portions (blood flow signals) where such temporal changes exist. Note that OCT angiography is also called OCT motion contrast imaging. Furthermore, images obtained by OCT angiography are called angiography images, angiograms, motion contrast images, and the like.

When OCT angiography is performed, the ophthalmologic imaging device 1 repeatedly scans the same region of the fundus Ef a predetermined number of times. For example, repeated scanning can be performed along a trajectory between two points on a predetermined scan pattern (eg, a spiral scan pattern). Image constructor 220 can construct motion contrast images from data sets collected by data acquisition system 130 in repeated scans. This motion contrast image is an angiographic image obtained by emphasizing temporal changes in interference signals caused by blood flow in the fundus Ef. Typically, OCT angiography is applied to a three-dimensional region of the fundus Ef, and an image representing the three-dimensional distribution of blood vessels in the fundus Ef is obtained.

When OCT angiography is performed, the image construction unit 220 can construct arbitrary two-dimensional angiography image data and/or arbitrary pseudo three-dimensional angiography image data from the three-dimensional angiography image data. It is. For example, the image constructing unit 220 can construct two-dimensional angiographic image data representing an arbitrary cross section of the fundus Ef by applying multi-sectional reconstruction to the three-dimensional angiographic image data.

The image construction unit 220 is realized by cooperation between hardware including a processor and image construction software.

<Data processing unit 230>
The data processing unit 230 includes a processor and applies various data processing to the image of the eye E to be examined. For example, the data processing unit 230 is realized by cooperation between hardware including a processor and data processing software.

The data processing unit 230 can perform registration between the two images acquired for the fundus Ef. For example, the data processing unit 230 can perform registration between three-dimensional image data obtained by OCT and a frontal image obtained by the fundus camera unit 2. Further, the data processing unit 230 can perform registration between two OCT images obtained by OCT. Furthermore, the data processing unit 230 can perform registration between the two frontal images acquired by the fundus camera unit 2. It is also possible to apply registration to the analysis results of OCT images and frontal images. Registration can be performed by a known method, and includes, for example, feature point extraction and affine transformation.

As illustrated in FIG. 4, the data processing unit 230 of this embodiment includes a parameter setting unit 231, a movement detection unit 232, and an aberration map creation unit 233.

<Parameter setting section 231>
The parameter setting unit 231 sets focus control parameters based on an OCT image of the fundus Ef acquired in advance. This OCT image (preparatory image) is used to detect the rough shape of the application area of the wide-angle OCT scan, and focus control parameters are set based on the detected shape.

The ophthalmologic imaging apparatus 1 can acquire OCT images used for setting focus control parameters. For example, the ophthalmologic imaging apparatus 1 can apply a preliminary OCT scan to the eye E to be examined before applying the wide-angle OCT scan to the eye E to be examined.

A preliminary OCT scan is performed through both the central region and the peripheral region of the wide-angle OCT scan application area. For example, in a preparatory OCT scan for a wide-angle OCT scan of the fundus Ef, the macular area (and its neighboring area) is set as the central area of the fundus Ef, and the area away from the macula by a predetermined distance or more is set as the peripheral area. can do. In addition, in a preparatory OCT scan for a wide-angle OCT scan of the anterior segment, the corneal apex and its surrounding area are set as the central region of the anterior segment, and the region away from the corneal apex by a predetermined distance or more is the peripheral region. Can be set to . More generally, it is possible to set the eye axis of the eye E to be examined and its neighboring region as the central region, and to set the region away from the eye axis by a predetermined distance or more as the peripheral region.

The preparatory OCT scan pattern may be a scan pattern including a large number of scan points, such as a three-dimensional scan (raster scan), but the purpose of the preparatory OCT scan is to determine the rough shape of the wide-angle OCT scan application area. Considering that it is grasping, relatively simple scan patterns such as B scan (line scan), cross scan, and radial scan are sufficient.

Image construction unit 220 constructs a preliminary image from data collected by the preliminary OCT scan. The preliminary images typically include one or more B-scan images representing one or more cross-sections of the central region and one or more cross-sections of the peripheral region of the wide-angle OCT scan application area.

Note that in the following example, the outer edge of the central region and the outer and inner edges of the peripheral region are both circular, but the shape of the central region and the shape of the peripheral region are not limited to these. For example, either the outer edge of the central region or the outer edge or inner edge of the peripheral region may be rectangular, or may have an arbitrary shape. Moreover, the outer edge shape and the inner edge shape of the peripheral edge region may be the same or may be different from each other.

The example preliminary OCT scan shown in FIG. 5A is one B-scan 330 that passes through a central region 310 of the fundus Ef that includes the macula Em, and a peripheral region 320 away from the macula Em (shaded region). . The symbol Ed indicates the optic disc. In this example, one B-scan image is obtained representing the cross-section to which B-scan 330 has been applied. The B-scan image of this example represents the relative relationship between the depth position (z position) of the central region 310 and the depth position of the peripheral region 320. In this example, the relative depth positional relationship between the central region 310 and the peripheral region 320 is obtained only in the direction in which the B-scan 330 is applied.

The example preliminary OCT scan shown in FIG. 5B is two B-scans 341 and 342, each passing through a central region 310 and a peripheral region 320. The two B-scans 341 and 342 are orthogonal to each other. That is, the preliminary OCT scan in this example is a cross scan. In this example, a B-scan image representing a cross-section to which B-scan 341 is applied and a B-scan image representing a cross-section to which B-scan 342 is applied are obtained. Each of the two B-scan images in this example represents the relative relationship between the depth position (z position) of the central region 310 and the depth position of the peripheral region 320. In this example, the relative depth positional relationship between the central region 310 and the peripheral region 320 is determined in the direction in which the B-scan 341 is applied and in the direction in which the B-scan 342 is applied, that is, in two directions that are orthogonal to each other. can get.

Although not shown, when a radial scan (a plurality of B scans arranged at equal angular intervals) is applied as a preliminary OCT scan, the central region and the peripheral region are The relative depth positional relationship between the two can be obtained. Also, although not shown, when a three-dimensional scan (for example, raster scan) is applied as a preparatory OCT scan, the relative depth position between the central region and the peripheral region in any direction in the xy plane. You get a relationship. Even when other scan patterns are applied, the relative depth positional relationship between the central region and the peripheral region can be obtained in one or more directions corresponding to the scan pattern.

The pattern of the preliminary OCT scan thus determines the content (such as direction) and amount (such as angular spacing) of information acquired as relative depth position relationships. Conversely, the pattern of the preliminary OCT scan can be determined depending on the content and amount of information desired to be acquired as a relative depth positional relationship. Determination of the preliminary OCT scan pattern is performed, for example, in advance or for each examination.

The data collected by the preliminary OCT scan is sent to the image construction unit 220 to construct a preliminary image. The parameter setting unit 231 sets one or more focus control parameters based on this preliminary image. As described above, the focus control parameters are parameters that indicate the content of control for the OCT focusing drive section 43A, and examples thereof include a parameter indicating the focal position of the measurement arm, a parameter indicating the moving speed of the focal position, and a parameter indicating the focal position. There is a parameter that indicates the movement acceleration of.

An example of processing executed by the parameter setting unit 231 will be described. An example of a preliminary image is shown in FIG. 6A. Preparatory image G is, for example, an image constructed from data collected in B-scan 330 shown in FIG. 5A (or B-scan 341 shown in FIG. 5B or a similar B-scan). The area outlined by the dotted line labeled 310 corresponds to the intersection area (common area) between the center area 310 and the B-scan 330 shown in FIG. 5A. The hatched area labeled 320 corresponds to the intersection area (common area) between the peripheral area 320 and the B-scan 330 shown in FIG. 5A. Note that there are two peripheral areas 320 in the preliminary image G. Moreover, the symbol Em is an image area of the macula, and the symbol Ed is an image area of the optic disc.

The parameter setting unit 231 analyzes the central region 310 of the preliminary image G, detects the macular region Em, and specifies its depth position (z coordinate). To this end, the parameter setting unit 231 performs, for example, segmentation to specify the image region of the internal limiting membrane (ILM), shape analysis to detect the macular region Em from the shape (indentation) of the specified internal limiting membrane region, and detection. The process includes a process of determining the z-coordinate of a pixel at a representative point of the macular region Em. The representative point of the macular region Em may be, for example, the center of the macula (fovea, the deepest part of the depression). Let the z-coordinate of the center of the macula determined by this example be _z1 (see FIG. 6B). Note that the location where the z coordinate is specified is not limited to the center of the macula, but may be any representative point within the central region 310.

Further, the parameter setting unit 231 analyzes the peripheral region 320 of the preliminary image G to detect an image region of a predetermined tissue (for example, the internal limiting membrane), and specifies its depth position (z coordinate). To this end, the parameter setting unit 231 includes, for example, segmentation for specifying an image region of a predetermined tissue, and processing for determining the z-coordinate of a pixel at a representative point of the specified image region. The representative point of the image region of the predetermined tissue may be, for example, the center position of the peripheral region 320 in the B-scan direction or the end point of the peripheral region 320. When the center positions of the two peripheral regions 320 of the preliminary image G are representative points, the z coordinates of the internal limiting membrane determined by this example are z ₂₁ and z ₂₂ (see FIG. 6C).

Further, the parameter setting unit 231 sets focus control parameters based on the z coordinate (z ₁ ) of the representative point of the central region 310 and the z coordinate (z ₂₁ , z ₂₂ ) of the representative point of the peripheral region 320. .

For example, the parameter setting unit 231 determines the position of the OCT focusing lens 43 corresponding to the z coordinate (z ₁ ) of the representative point of the central region 310 and the z coordinate (z ₂₁ and z ₂₂ of the representative point of the peripheral region 320, respectively). ) can be determined. The position of the OCT focusing lens 43 corresponds to the focal position of the measurement arm. This example can be said to be a process for determining the absolute position of the OCT focusing lens 43. The processing in this example is based on, for example, the coherence gate position (arm length, position of the retroreflector 41, position of the retroreflector 114) when the preliminary image G is acquired, and the scale of the z-axis (e.g., the number of pixels per pixel). distance).

The parameter setting unit 231 determines the position (focal position) of the OCT focusing lens 43 corresponding to the z coordinate (z ₁ ) of the representative point of the central region 310 and the z coordinates (z ₂₁ and z _{22 )} of the representative point of the peripheral region 320. ) and the corresponding position (focal position) of the OCT focusing lens 43 can be found. In other words, this example can be said to be a process for determining the relative position of the OCT focusing lens 43. The processing in this example is executed based on, for example, the scale of the z-axis.

The parameter setting unit 231 determines the position (focal position) of the OCT focusing lens 43 corresponding to the z coordinate (z ₁ ) of the representative point of the central region 310 and the z coordinates (z ₂₁ and z _{22 )} of the representative point of the peripheral region 320. It is possible to obtain a focal position change range including the position (focal position) of the OCT focusing lens 43 corresponding to each of the following. The focus position change range is the range of the focus position that is changed by focus control, and is defined, for example, as the movement range of the OCT focusing lens 43. The processing of this example is executed based on, for example, the coherence gate position when the preliminary image G was acquired and the scale of the z-axis.

The parameter setting unit 231 can set the speed at which the focal position of the measurement arm is moved. The processing of this example is executed, for example, based on the absolute position or relative position of the OCT focusing lens 43 described above, or based on the movement range of the OCT focusing lens 43.

The parameter setting unit 231 can set the acceleration for moving the focal position of the measurement arm. The processing of this example is performed based on the absolute position or relative position of the OCT focusing lens 43, based on the moving range of the OCT focusing lens 43, or based on the moving speed of the OCT focusing lens 43, for example. , executed.

When the preliminary image G is obtained, for example, as shown in FIG. 7, the focal position moves in the +z direction from the left side of the peripheral area 320 toward the center area 310, and from the center area 310 side to the right side. The parameter setting unit 231 sets the focus control parameters so that the focal position moves in the −z direction as it moves toward the peripheral area 320 side.

The parameter setting unit 231 can set information representing the relationship between the scan control parameter and the focus control parameter, for example, based on any of the examples of the focus control parameters described above.

As a premise, a scan pattern for wide-angle OCT scan is set. The wide-angle OCT scan pattern is set, for example, in advance or for each examination.

In this embodiment, the wide-angle OCT scan pattern includes a continuous first partial pattern for the central region of the wide-angle OCT scan application area and a continuous second partial pattern for the peripheral region. The first partial pattern is a pattern for continuously scanning at least a portion of the central region, and the second partial pattern is a pattern for continuously scanning at least a portion of the peripheral region. Here, "scanning continuously" means, for example, sequentially scanning a plurality of scan points arranged in a predetermined pattern according to the arrangement order.

The wide-angle OCT scan pattern may include a curved scan pattern defined by a polar coordinate system with the origin at the center of the wide-angle OCT scan area. The center of the wide-angle OCT scan application area may be, for example, the center of the macula, or may be another part of the fundus. In this way, the center of the wide-angle OCT scan application area may be defined using the site or tissue of the eye to be examined as a reference, but it is also possible to define it using the ophthalmologic imaging apparatus 1 as a reference. For example, the center of the wide-angle OCT scan application area may be defined as the neutral position (neutral orientation) of a variable orientation mirror (such as a galvano mirror) of the optical scanner 44, or the center of the optical axis of the measurement arm (the optical axis of the objective lens 22). ) may be defined as the position of Examples of a curved wide-angle OCT scan pattern defined by a polar coordinate system with the origin at the center of the wide-angle OCT scan application area include a spiral pattern, a concentric pattern, and the like.

When the wide-angle OCT scan pattern is the above-mentioned curved scan pattern, the wide-angle OCT scan pattern is a spiral scan pattern from the center to the outer edge of the wide-angle OCT scan application area (see spiral scan pattern 510 shown in FIG. 8A). , or a spiral scan pattern from the outer edge toward the center of the wide-angle OCT scan application area (see spiral scan pattern 520 shown in FIG. 8B).

The spiral scan pattern 510 shown in FIG. 8A starts scanning from the center of the macula in the central region (not shown), and passes through the peripheral region (not shown) while increasing the radius as the declination changes. The scan ends at the outer edge (nearby).

The spiral scan pattern 520 shown in FIG. 8B starts scanning at the outer edge (nearby), passes through the peripheral area (not shown) while decreasing the vector radius as the declination changes, and then moves to the central area (not shown). The end point of the scan is set at the center of the macula.

Note that in each of the spiral scan patterns 510 and 520, the intervals between spirals are drawn more roughly than they actually are for illustration purposes. In reality, for example, the intervals between the spirals may be close enough to construct three-dimensional image data.

Some examples of focus control parameters that can be set by the parameter setting unit 231 when the wide-angle OCT scan pattern is the aforementioned curved scan pattern (for example, a spiral scan pattern) will be explained with reference to FIGS. 9A to 9D. .

Note that the focus control parameters that can be set by the parameter setting unit 231 are not limited to these examples, and may be any focus control parameters that satisfy the conditions required in this embodiment.

In the example shown in FIG. 9A, the horizontal axis of the coordinate system indicates the scan position, and the vertical axis indicates the focal position. The scan position on the horizontal axis is defined as the number n (n=0, 1, 2, . . . , N-1) of N scan points ordered according to the applied scan pattern. Further, the focal position on the vertical axis is defined as the z coordinate. The focus control parameters in FIG. 9A are applicable when a spiral scan pattern from the center to the outer edge of the wide-angle OCT scan application area is employed, such as the spiral scan pattern 510 shown in FIG. 8A, for example. Hereinafter, a description will be given along with a spiral scan pattern 510 as an example.

The first scan position n=0 in FIG. 9A corresponds to the scan start point (macula center) in the spiral scan pattern 510, and the last scan position n=N-1 corresponds to the scan end point (macular center) in the spiral scan pattern 510. position on the outer edge or near the outer edge).

The focus position ζ ₁₁ assigned to the scan start position n=0 is set, for example, based on the z-coordinate z ₁ of the central region 310 (for example, the center of the macula) shown in FIG. 6B. For example, ζ ₁₁ is set equal to z ₁ or ζ ₁₁ is set approximately equal to z ₁ .

The focus position ζ ₁₂ assigned to the scan end position n=N-1 is set, for example, based on at least one of the z coordinates z ₂₁ and z ₂₂ of the peripheral area 320 shown in FIG. 6C. For example, ζ ₁₂ is set equal to z ₂₁ , ζ ₁₂ is set approximately equal to z ₂₁ , ζ ₁₂ is set equal to z ₂₂ , or ζ ₁₂ is approximately equal to z ₂₂ . or ζ ₁₂ is set to the value obtained from both z ₂₁ and z ₂₂ . Examples of calculating ζ ₁₂ from both z ₂₁ and z ₂₂ include calculating the average of z ₂₁ and z ₂₂ , calculating the weighted average of z ₂₁ and z ₂₂ , and calculating ζ 12 from both z ₂₁ and z 22. Any statistical processing can be used, such as selecting the larger or smaller value of ₂₂ .

The focus control parameters shown in FIG. 9A define coordinates (0, ζ ₁₁ ) corresponding to the scan start point and coordinates (N-1, ζ ₁₂ ) corresponding to the scan end point in the two-dimensional coordinate system (n, z). It can be set as a connecting smooth curve (for example, a spline curve, a Bezier curve).

The two-dimensional coordinate system (n, z) in the example shown in FIG. 9B is the same as that in the example shown in FIG. 9A. The focus control parameters in FIG. 9B are applicable when a spiral scan pattern from the outer edge toward the center of the wide-angle OCT scan application area is employed, such as the spiral scan pattern 520 shown in FIG. 8B, for example. Hereinafter, a description will be given along with a spiral scan pattern 520 as an example.

The first scan position n=0 in FIG. 9B corresponds to the scan start point (position on the outer edge or position near the outer edge) in the spiral scan pattern 520, and the last scan position n=N-1 corresponds to the spiral scan pattern 520. This corresponds to the scan end point (center of the macula) in pattern 520.

The focus position ζ ₂₁ assigned to the scan start position n=0 can be set, for example, in the same manner as the focus position ζ ₁₂ in FIG. 9A. Further, the focus position ζ ₂₂ assigned to the scan end position n=N-1 can be set, for example, in the same manner as the focus position ζ ₁₁ in FIG. 9A.

The focus control parameters shown in FIG. 9B define coordinates (0, ζ ₂₁ ) corresponding to the scan start point and coordinates (N-1, ζ ₂₂ ) corresponding to the scan end point in the two-dimensional coordinate system (n, z). It can be set as a connecting smooth curve (for example, a spline curve, a Bezier curve).

The two-dimensional coordinate system (n, z) in the example shown in FIG. 9C is the same as that in the example shown in FIG. 9A. The focus control parameters in FIG. 9C are applicable when a spiral scan pattern from the center to the outer edge of the wide-angle OCT scan application area is employed, such as the spiral scan pattern 510 shown in FIG. 8A, for example. Hereinafter, a description will be given along with a spiral scan pattern 510 as an example.

The first scan position n=0 in FIG. 9C corresponds to the scan start point (macula center) in the spiral scan pattern 510, and the last scan position n=N-1 corresponds to the scan end point (macular center) in the spiral scan pattern 510. position on the outer edge or near the outer edge).

The focus position ζ ₃₁ assigned to the scan position interval n=[0, n ₃₁ ] can be set, for example, in the same manner as the focus position ζ ₁₁ in FIG. 9A. Further, the focus position ζ ₃₃ assigned to the scan position interval n=[n ₃₂ , N-1] can be set, for example, in the same manner as the focus position ζ ₁₂ in FIG. 9A. Furthermore, the focus position ζ ₃₂ assigned to the scan position interval n=(n ₃₁ , n ₃₂ )=[n ₃₁ +1, n ₃₂ −1] can be set based on the focus positions ζ ₃₁ and ζ ₃₃ , for example. be. Typically, the focal position ζ ₃₂ is determined, for example, by any statistical processing. Examples of statistical values to be obtained include the average of ζ ₃₁ and ζ ₃₃ , the weighted average of ζ ₃₁ and ζ ₃₃ , the larger value of ζ ₃₁ and ζ ₃₃ , and the value of ζ ₃₁ and ζ ₃₃ . There is a smaller value, etc.

Similar to the relationship between the focus control parameters shown in FIG. 9A and the focus control parameters shown in FIG. 9B, the stepped focus control parameters shown in FIG. 9C can be reversed. The focus control parameters obtained by inversion can be applied when a spiral scan pattern from the outer edge to the center of the wide-angle OCT scan application area is employed, such as the spiral scan pattern 520 shown in FIG. 8B, for example.

Further, it is possible to modify the focus control parameters shown in FIG. 9C. For example, a smooth curve (e.g., spline curve, Bezier curve) connecting the coordinates (0, ζ ₃₁ ) and the coordinates (n ₃₁ , ζ ₃₂ ) is assigned to the scan position interval n = [0, n ₃₁ ]. be able to. In addition, a smooth _curve connecting the coordinates (n ₃₂ , ζ ₃₂ ) and the coordinates (N-1, ζ ₃₃ ) (for example, a spline curve, a Bezier curve) can be assigned. For example, when a spiral scan pattern 520 shown in FIG. 8B, which goes from the outer edge to the center of the wide-angle OCT scan application area, is adopted, the focus control parameter whose part is replaced with a curved line in this way is It is possible to reverse.

Alternatively, a straight line (diagonal line) connecting the coordinates (0, ζ ₃₁ ) and the coordinates (n ₃₁ , ζ ₃₂ ) can be assigned to the scan position section n=[0, n ₃₁ ]. Furthermore, a straight line (diagonal line) connecting the coordinates (n ₃₂ , ζ ₃₂ ) and the coordinates (N-1, ζ ₃₃ ) can be assigned to the scan position section n=[n ₃₂ , N-1]. For example, when a spiral scan pattern 520 shown in FIG. 8B is adopted, such as a spiral scan pattern that goes from the outer edge to the center of the wide-angle OCT scan application area, the focus control parameter whose part is replaced with diagonal lines in this way is It is possible to reverse.

The two-dimensional coordinate system (n, z) in the example shown in FIG. 9D is the same as that in the example shown in FIG. 9A. The focus control parameters in FIG. 9D are applicable when a spiral scan pattern from the center to the outer edge of the wide-angle OCT scan application area is employed, such as the spiral scan pattern 510 shown in FIG. 8A, for example. Hereinafter, a description will be given along with a spiral scan pattern 510 as an example.

The first scan position n=0 in FIG. 9D corresponds to the scan start point (macular center) in the spiral scan pattern 510, and the last scan position n=N-1 corresponds to the scan end point (macular center) in the spiral scan pattern 510. position on the outer edge or near the outer edge).

The focus position ζ ₄₁ assigned to the scan position interval n=[0, n ₄₁ ] can be set, for example, in the same manner as the focus position ζ ₁₁ in FIG. 9A. Further, the focus position ζ ₄₂ assigned to the scan position interval n=[n ₄₂ , N-1] can be set, for example, in the same manner as the focus position ζ ₁₂ in FIG. 9A. Furthermore, the coordinates (n ₄₁ , ζ ₄₁ ) and the coordinates (n ₄₂ , ζ ₄₂ ) are connected to the scanning position section n=(n ₄₁ , n ₄₂ )=[n ₄₁ +1, n ₄₂ -1]. A straight line is assigned.

Similar to the relationship between the focus control parameters shown in FIG. 9A and the focus control parameters shown in FIG. 9B, the focus control parameters shown in FIG. 9D can be reversed. The focus control parameters obtained by inversion can be applied when a spiral scan pattern from the outer edge to the center of the wide-angle OCT scan application area is employed, such as the spiral scan pattern 520 shown in FIG. 8B, for example.

Further, it is possible to modify the focus control parameters shown in FIG. 9D. For example, in the scan position interval n = (n ₄₁ , n _{42 )} = [n _{41 +1} , n _{42 -1 ]} , a smooth curves (eg, spline curves, Bezier curves) can be assigned. For example, when a spiral scan pattern 520 shown in FIG. 8B, which goes from the outer edge to the center of the wide-angle OCT scan application area, is adopted, the focus control parameter whose part is replaced with a curved line in this way is It is possible to reverse.

Although examples of processing executed by the parameter setting unit 231 and examples of focus control parameters created thereby have been described above, these are not intended to be limiting, and various modifications are allowed.

For example, in the example shown in FIG. 6B, the depth position (z coordinate) of one representative point (macula center) within the central region 310 is determined and used as the depth position of the central region 310. On the other hand, it is possible to determine the depth positions of two or more points within the central region, and to determine the depth position of the central region from the two or more determined depth positions. For example, the depth position of the central region can be determined by applying statistical processing to two or more depth positions. The statistical value obtained from two or more depth positions may be, for example, an average value, a weighted average value, an intermediate value, a mode, a maximum value, or a minimum value. Similar processing can be applied when determining the depth position of the peripheral area.

When determining two or more depth positions within the central region, instead of calculating a single statistical value from these depth positions as described above and using this as the depth position of the central region, Information representing changes in depth position within the central region can be obtained from . For example, based on these depth positions, a graph (focus control parameter) representing a curved, linear, or stepwise change in depth position in the central region can be obtained. 9A and 9B are examples of curved changes. Although not shown, as an example of a linear change in the depth position in the central region, in the two-dimensional coordinate system shown in FIG. 9C, coordinates (0, ζ ₃₁ ) and coordinates (n ₃₁ , ζ ₃₂ ) are connected. It is possible to find a straight line. Although not shown, as an example of a stepwise change in the depth position in the central region, in the two-dimensional coordinate system shown in FIG. 9C, the focus _position is It is possible to set a focus control parameter whose value changes in steps from ζ ₃₁ to ζ ₃₂ . Similar processing can be applied when determining the focus control parameters for the peripheral area.

As described above, the process of determining two or more depth positions within the center area and setting the focus control parameters is useful, for example, when the width of the center area (length in the direction perpendicular to the z direction) is relatively wide. This is considered to be effective when there is a large change in the depth position within the central region (for example, when there is a large difference between the maximum depth position and the minimum depth position within the central region). The parameter setting unit 231 determines the number of points in the central region for which the depth region is calculated depending on the width of the central region and/or the magnitude of change in depth position within the central region. (and location). Similar processing can be applied when determining the focus control parameters for the peripheral area.

In the example described above, the central region (310) and the peripheral region (320) are spaced apart from each other. In other words, in the example described above, an annulus-shaped intermediate region exists between the outer edge of the central region and the inner edge of the peripheral region. In other examples, the outer edge of the central region and the inner edge of the peripheral region may coincide.

More generally, in this embodiment, the central region and the peripheral region can be arbitrarily defined. For example, the central region and the peripheral region may be defined depending on the location of the fundus. As a specific example, a region centered on a predetermined part of the fundus (for example, the center of the macula) and within a predetermined first distance from the center can be set as the central region. Furthermore, an area that is a predetermined second distance (a distance greater than or equal to the first distance) from the center can be set as the peripheral area. Here, a third distance representing the outer edge of the peripheral area may be further set, or the outer edge of the wide-angle OCT scan application area may be set to the outer edge of the peripheral area. The distance in this example may be a distance on the fundus, an optically calculated distance, or a standard distance obtained from an eye model or clinical data.

Other definitions of central and peripheral regions include definitions according to OCT scans. For example, it is possible to set a predetermined first region in the wide-angle OCT scan application area as the center region, and set a predetermined second region different from the second region as the peripheral region. Typically, a first region including the center of the wide-angle OCT scan application area is set as the center region, and a second region located outside the first region is set as the peripheral region.

In the example described above, a scan pattern consisting of a curved line such as a spiral scan pattern has been particularly described, but it is also possible to employ a scan pattern at least partially consisting of a straight line. For example, by alternately combining line scans in the x direction and line scans in the y direction, a spiral scan pattern consisting of a plurality of straight lines can be applied.

The settings of the wide-angle OCT scan pattern and focus control parameters (and scan speed) exemplified above include settings of the movement speed and/or movement acceleration of the focal position. For example, in the focus control parameters illustrated in each of FIGS. 9A to 9D, the slope of the graph showing the focus control parameters corresponds to the moving speed, and the rate of change of the slope of the graph corresponds to the moving acceleration. Conversely, it is possible to set the focus control parameters by setting the movement speed and/or movement acceleration of the focus position.

In the focus control parameters illustrated in each of FIGS. 9A to 9D, the focus position (first focus position) applied to the center region is on the +z side of the focus position (second focus position) applied to the peripheral region. Located in That is, the focal length corresponding to the first focal position (first focal length) is set longer than the focal length corresponding to the second focal position (second focal length). This depends on the shape of the eye (fundus) to be examined. However, the first focal length does not need to be longer than the second focal length.

The parameter setting unit 231 capable of executing the above-described processing is realized by cooperation between hardware including a processor and parameter setting software.

<Movement detection unit 232>
The ophthalmologic photographing apparatus 1 includes a fundus camera unit 2 that repeatedly photographs the eye E to be examined to obtain time-series images. The time-series images acquired by the fundus camera unit 2 are, for example, the aforementioned observation images.

The movement detection unit 232 analyzes the observation image acquired by the fundus camera unit 2 and detects movement of the eye E to be examined. For example, the movement detection unit 232 analyzes each image included in the observed images to detect feature points, and determines time-series changes in the positions of the feature points. The feature points may be, for example, the center, center of gravity, and outline of the pupil, and the center, center of gravity, and outline of the iris.

At least in parallel with the operation of the aberration correction control section 215, the scan control section 213 controls the optical scanner 44 and the OCT unit 100 according to the wide-angle OCT scan pattern, and controls the optical scanner 44 based on the output from the movement detection section 213. can be controlled. Control of the optical scanner 44 based on the output from the movement detection section 213 is so-called tracking control.

Tracking is performed, for example, by the following series of processes disclosed in Japanese Patent Application Publication No. 2017-153543. First, the movement detection unit 232 registers any frame (frontal image) of the observation images acquired by the fundus camera unit 2 as a reference image.

Further, the movement detection unit 232 determines a change in the position of the feature point in another frame with respect to the position of the feature point in the reference image. This corresponds to finding the time-series change in the position of the feature point, that is, finding the displacement between the reference image and other frames. Note that if the displacement exceeds a threshold or becomes impossible to detect due to blinking or fixation shift, the movement detection unit 232 can register the subsequently acquired frame as a new reference image. . Furthermore, the method for determining the time-series change in the position of the feature point is not limited to this, and for example, the displacement of the feature point between two consecutive frames may be determined sequentially.

The movement detection unit 232 sends control information for canceling the time-series change to the scan control unit 213 every time a time-series change in the position of the feature point is determined. At least in parallel with the operation of the aberration correction control section 215, the scan control section 213 corrects the orientation of the optical scanner 44 based on control information that is sequentially input.

The movement detection unit 232 is realized by cooperation between hardware including a processor and movement detection software.

<Aberration map creation unit 233>
The aberration map creation unit 233 creates an aberration map. The created aberration map (219) is stored in the storage unit 212.

For example, the aberration map creation unit 233 can create an aberration map based on the OCT image of the fundus Ef. An example of processing for creating an aberration map from an OCT image will be described below with reference to FIG.

In this example, a wide-angle OCT scan is applied to the fundus Ef using the ophthalmologic imaging device 1 (or other ophthalmology imaging device) to obtain a wide-angle OCT image, and the shape of the fundus Ef is grasped from this wide-angle OCT image. An aberration map is created based on the fundus shape and a predetermined fundus shape-aberration database.

The fundus shape-aberration database is a database representing the relationship between fundus shape and aberration, and is created by actually performing aberration measurements on eyes with various fundus shapes. The fundus shape-aberration database is stored in the ophthalmologic imaging device 1 or other device, and can be referenced by the aberration map creation unit 233.

A plurality of B-scan images 600u (u=1, 2, . . . , U: U is an integer of 2 or more) shown in FIG. 10 are examples of OCT images obtained by wide-angle OCT scanning of the fundus Ef.

The aberration map creation unit 233 analyzes each B-scan image 600u to determine the shape of the fundus Ef. To this end, the aberration map creation unit 233, for example, identifies the pixel of maximum brightness from each A-scan image constituting the B-scan image 600u, thereby determining the position (z, z) of the fundus Ef at each A-scan position (x, y). location). For example, as shown in FIG. 10, the maximum brightness pixel 610uv at each A-scan position is specified (v=1, 2,..., Vu: Vu is 2 or more pixels set for each B-scan image 600u). integer). As a result, the shape (x, y, z) of the fundus Ef depicted in each B-scan image 600u is obtained.

Note that instead of specifying the pixel with the maximum brightness, for example, an image of a predetermined fundus tissue may be specified by segmentation. The identified fundus tissues include the internal limiting membrane, nerve fiber layer, ganglion cell layer, and retinal pigment epithelial layer. Note that the method for detecting the position (shape) of the fundus is not limited to these, and any method can be adopted.

Next, the aberration map creation unit 233 refers to the fundus shape-aberration database to obtain, for example, an aberration (aberration correction amount) corresponding to the z position of the fundus Ef at each A-scan position (x, y). By performing this process for a plurality of A-scan positions (x, y), a distribution of aberration correction amounts in the area to which the wide-angle OCT scan is applied can be obtained. This aberration correction amount distribution is used as an aberration map.

It is not necessary to create an aberration map for the entire area to which the wide-angle OCT scan was applied. In other words, an aberration map may be created for only a part of the area to which the wide-angle OCT scan is applied. For example, it is possible to create an aberration map in which aberration correction amounts are recorded only for locations where the aberration correction amounts are equal to or greater than a predetermined threshold. Further, it is possible to create an aberration map in which the aberration correction amount is recorded only for a predetermined region (for example, a peripheral region or a region including a part thereof).

The created aberration map is stored in the storage unit 212. Here, either the identification information of the subject or the identification information of the eye E to be examined can be associated with the created aberration map. Furthermore, creation date information and the like can be associated with the created aberration map. This makes it possible to use an aberration map for each subject and an aberration map for each eye to be examined. The aberration correction control unit 215 reads an aberration map associated with the input identification information (subject identification information, eye identification information) from the storage unit 212 and uses it.

The aberration map created by the aberration map creation unit 233 in this way is not a standard or statistical aberration map, but is an individual aberration map created by actually measuring the eye E to be examined. If both the individual aberration map and the standard aberration map are stored in the storage unit 212, either one may be used in the aberration correction control, but typically, the individual aberration map corresponding to the eye E is An aberration map is selected.

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

<motion>
The operation of the ophthalmologic imaging device 1 will be explained. It is assumed that the same preparatory processes as in the past have already been performed, such as inputting the patient ID, presenting a fixation target, adjusting the fixation position, alignment, focus adjustment, and OCT optical path length adjustment.

An example of the operation of the ophthalmologic imaging apparatus 1 will be described with reference to FIG. 11.

(S1: Apply a preliminary OCT scan to the fundus to obtain a preliminary image)
First, the ophthalmologic imaging apparatus 1 uses the optical scanner 44 and the OCT unit 100 to apply a preliminary OCT scan to the fundus Ef. The preliminary OCT scan is, for example, a wide-angle OCT scan. Image construction unit 220 constructs a preliminary image from data collected by the preliminary OCT scan. The preliminary image is sent to the parameter setting section 231.

(S2: Set control parameters and create aberration map)
The parameter setting unit 231 sets focus control parameters based on the preliminary image obtained in step S1. The set control parameters are stored in the storage unit 212, for example.

In addition, at step S2 or a stage before it, the ophthalmologic imaging apparatus 1 may set a wide-angle OCT scan application area, set a center region, set a peripheral region, set scan control parameters, etc. Note that any of these conditions may be a fixed condition, a condition selected from a plurality of options, or a condition manually set by the user. The parameter setting unit 231 may set the focus control parameters based on the results of these settings and the preliminary image.

In this example, it is assumed that the center region 310 and peripheral region 320 shown in FIG. 5A, the spiral scan pattern 510 shown in FIG. 8A, and the focus control parameters shown in FIG. 9A are applied. It is also assumed that the outer edge of the peripheral region 320 defines the outer edge of the wide-angle OCT scan application area.

Further, the aberration map creation unit 233 creates an aberration map of the eye E to be examined based on the preliminary image acquired in step S1. The created aberration map is stored in the storage unit 212.

(S3: Control the optical scanner based on the scan start position)
The scan control unit 213 specifies a scan start position based on the scan control parameters set in step S2 or an earlier step, and controls the optical scanner 44 based on this scan start position. Thereby, each galvanometer mirror included in the optical scanner 44 is arranged in a direction corresponding to the scan start position.

In this example, typically, a fixation target corresponding to the fixation position for acquiring an image centered on the macula is displayed on the LCD 39, and the center of the wide-angle OCT scan application area is set at the center of the macula. Ru. Assuming that the alignment state and fixation state of the eye E to be examined are suitable, the center of the macula is placed on the optical axis of the measurement arm. Therefore, in this example, each galvanometer mirror of the optical scanner 44 is arranged at a neutral position.

(S4: Move the OCT focusing lens based on the initial focus position)
The focus control unit 214 specifies the initial focus position in focus control based on the focus control parameters set in step S2, and controls the OCT focus drive unit 43A based on this initial focus position to move the OCT focus lens 43. move it.

In this example, the focus position ζ ₁₁ corresponding to the scan start position n=0 shown in FIG. 9A is specified as the initial focus position, and the OCT focusing lens 43 is arranged at the position corresponding to this initial focus position ζ ₁₁ . Control of the OCT focusing drive unit 43A is executed.

Note that the control related to step S4 may be executed before the control related to step S3. Further, the control related to step S3 and the control related to step S4 may be performed in parallel.

(S5: Control the aberration correction device based on the initial aberration correction amount)
The aberration correction control unit 215 specifies the initial aberration correction amount in the aberration correction control based on the aberration map created in step S2. For example, the aberration correction control unit 215 can obtain the aberration correction amount corresponding to the scan start position (x, y) specified in step S3 from the aberration map.

At this time, if any of the plurality of scan positions defined in the aberration map matches the scan start position specified in step S3, the aberration correction control unit 215, for example, selects the scan position that matches the scan start position. Set the aberration correction amount to the initial aberration correction amount.

Further, if none of the plurality of scan positions defined in the aberration map matches the scan start position specified in step S3, the aberration correction control unit 215, for example, Among them, the scan position closest to the scan start position is specified, and the aberration correction amount at the specified scan position is set as the initial aberration correction amount.

The aberration correction control unit 215 controls the aberration correction device 47 so that the specified initial aberration correction amount is applied.

(S6: Instruction to start wide-angle OCT scan)
After the control related to step S3, the control related to step S4, and the control related to step S5 are completed, a wide-angle OCT scan start instruction is input to the scan control section 213, focus control section 214, and aberration correction control section 215. This instruction may be given manually by the user, or upon completion of a predetermined condition (for example, completion of the control related to step S3, the control related to step S4, and the control related to step S5). The main control unit 211 may also perform this automatically.

(S7: Start linked execution of scan control, focus control, and aberration correction control)
Upon receiving the start instruction in step S6, the scan control section 213, focus control section 214, and aberration correction control section 215 start controlling in a coordinated manner, thereby starting a wide-angle OCT scan.

In this example, scan control by the scan control unit 213 and focus control by the focus control unit 214 are performed based on the focus control parameters (graph representing the relationship between the scan position n and the focus position z) shown in FIG. 9A. . Furthermore, in parallel with these controls, aberration correction control by the aberration correction control section 215 is executed.

To explain in more detail, the scan control unit 213 sequentially controls a plurality of scan points (scan positions n=0 to N-1 shown in FIG. 9A) arranged along the spiral scan pattern 510 shown in FIG. 8A. The optical scanner 44 and the OCT unit 100 are controlled so that the A-scan is applied to.

In parallel with this, when the A scan is applied to each scan position n shown in FIG. The OCT focusing drive section 43A is controlled so that the OCT focusing lens 43 is arranged.

Furthermore, in parallel with these, when the A scan is applied to each scan position n shown in FIG. 9A, the aberration correction control unit 215 specifies the scan position in the aberration map corresponding to this scan position n, The aberration correction device 47 is controlled so that the aberration correction amount associated with the specified scan position is applied. Note that the aberration correction amount corresponding to each scan position n shown in FIG. 9A can be obtained before starting the wide-angle OCT scan.

Through such parallel control, the fundus is moved according to the spiral scan pattern 510 shown in FIG. 8A while moving the focal position according to the focus control parameters shown in FIG. 9A and changing the aberration correction amount according to the aberration map. It is possible to scan Ef.

(S8: Start tracking)
In response to the start of the cooperative control in step S7, or at any timing before the start of the cooperative control, the projection position of the measurement light LS (A-scan application position) is adjusted in accordance with the movement of the eye E to be examined. ) tracking is started. Tracking is performed by the fundus camera unit 2, movement detection section 232, scan control section 213, etc. in the manner described above. This makes it possible to apply the spiral scan pattern 510 shown in FIG. 8A even if the subject's eye E moves during the wide-angle OCT scan.

(S9: Wide-angle OCT scan completed)
The wide-angle OCT scan started in step S7 ends, for example, after the OCT scan along the spiral scan pattern 510 shown in FIG. 8A is performed.

Note that the OCT scan along the wide-angle OCT scan pattern is executed a predetermined number of times, which is one or more times. For example, an OCT scan along spiral scan pattern 510 can be performed more than once. In this case, in the next step S9, two or more OCT images are constructed from two or more data sets collected by these two or more OCT scans, and these two or more OCT images are combined (added average). be able to.

(S10: Build an OCT image according to the wide-angle OCT scan pattern)
The image construction unit 220 constructs an OCT image from the data collected by the wide-angle OCT scan performed in steps S7 to S9.

The spiral scan pattern 510 shown in FIG. 8A is typically defined using a two-dimensional polar coordinate system (r, θ). Using a two-dimensional polar coordinate system (r, θ), the spiral scan pattern 510 is defined, for example, by the following equation: x=cos θ−θ×sin θ, y=sin θ+θ×cos θ.

In this case, the OCT image constructed in step S10 is also defined using a two-dimensional polar coordinate system (r, θ). That is, the positions of the plurality of A-scan images constituting the OCT image constructed in step S10 are defined using a two-dimensional polar coordinate system (r, θ).

In this example, since the positions of the plurality of A scans forming the spiral scan pattern 510 shown in FIG. 8A correspond to the plurality of scan positions n=0 to N-1 shown in FIG. 9A, the construction is performed in step S10. The positions of the plurality of A-scan images taken also correspond to the plurality of scan positions n=0 to N-1, respectively. For example, in step S10, an OCT image _H1 shown in FIG. 12 is constructed. The OCT image _H1 is composed of A-scan images A( _np ) assigned to each scan position n= _np . Note that each scan position n= _np is defined using a two-dimensional polar coordinate system (r, θ).

Note that the definition equation of the spiral scan pattern is not limited to this example, and the coordinate system that defines the wide-angle OCT scan pattern and OCT image is not limited to the two-dimensional polar coordinate system.

(S11: Apply coordinate transformation to OCT image)
The image construction unit 220 applies coordinate transformation to the OCT image constructed in step S10.

For example, when a wide-angle OCT scan pattern including a curved scan pattern defined in a polar coordinate system with the origin at the center of the OCT scan application area is applied, the image construction unit 220 constructs the eye to be examined according to this curved scan pattern. An OCT image defined in a polar coordinate system is formed from data collected by the OCT scan applied to the image (S10), and this OCT image is converted into an image defined in a three-dimensional orthogonal coordinate system (S11).

When the OCT image _H1 shown in FIG. 12 is constructed in step S10, the image construction unit 220 generates a coordinate transformation formula between the two-dimensional polar coordinate system (r, θ) and the two-dimensional orthogonal coordinate system (x, y). Accordingly, the coordinates of each scan position n= _np defined in the two-dimensional polar coordinate system (r, θ) are converted into coordinates defined in the two-dimensional orthogonal coordinate system (x, y). This coordinate transformation formula is, for example, the above-mentioned (x=cosθ−θ×sinθ, y=sinθ+θ×cosθ).

Through such coordinate transformation, for example, a group of OCT images H ₂ (m) (m=1, 2, . . . , M) shown in FIG. 13 is obtained. Each OCT image H ₂ (m) is a B-scan image along the x direction, and is defined using a two-dimensional orthogonal coordinate system (x, z). Furthermore, M OCT images H ₂ (1) to H ₂ (M) are arranged along the y direction. In this way, the M OCT images H ₂ (1) to H ₂ (M) are defined using a three-dimensional orthogonal coordinate system (x, y, z).

(S12: Build a three-dimensional image from the coordinate-transformed OCT image)
The image construction unit 220 can construct a three-dimensional image from the coordinate-transformed OCT image obtained in step S11.

In this example, in step S11, for example, M OCT images H ₂ (1) to H ₂ (M), which are stack data, are obtained. The image construction unit 220 can construct volume data by converting M OCT images H ₂ (1) to H ₂ (M) into voxels.

(S13: Display rendered image of 3D image)
The image construction unit 220 can render the three-dimensional image constructed in step S12. The main control unit 211 can cause the display unit 241 to display the rendered image thus obtained.

<Action/Effect>
Functions and effects of exemplary embodiments will be described.

An ophthalmologic imaging device (1) according to an exemplary embodiment includes a data collection section, a storage section, an aberration correction section, and a control section.

The data collection unit collects data by scanning the posterior segment of the eye (E) with light. In the above example, the data acquisition unit includes the OCT unit 100 and elements in the fundus camera unit 2 that constitute the measurement arm (retroreflector 41, OCT focusing lens 43, optical scanner 44, objective lens 22, etc.) .

Although the data collection unit in the above example has an OCT function, the data collection unit is not limited to this, and any data collection unit may be used as long as it is capable of collecting data on the posterior segment of the eye through optical scanning. For example, the data collection unit may have an SLO function.

The storage unit stores in advance a map (aberration map) representing the distribution of the aberration correction amount in a specific area that is at least a part of the scan area by the data collection unit. In the above example, the storage unit includes storage unit 212.

The aberration correction unit corrects at least aberrations caused by the eye to be examined (E). In the above example, the aberration correction section includes the aberration correction device 47.

The control unit coordinately controls a data collection unit for scanning a region of the posterior eye segment corresponding to a specific area of the aberration map, and controls an aberration correction unit based on the aberration map. In the above example, the control unit includes a main control unit 211, a scan control unit 213 controls the data acquisition unit, and an aberration correction control unit 215 controls the aberration correction unit.

According to the present embodiment, since the scan is performed while performing aberration correction according to the shape of the fundus using an aberration map obtained in advance, the aberration correction amount can also be measured while performing the scan. There is no need to perform any calculations. In contrast, in the prior art, aberrations are corrected by adaptive optics using active optics, so aberrations must be measured and aberration correction amount calculations performed while scanning.

Note that, except in cases such as before and after surgery or during long-term observation of a disease, the shape of the fundus of the eye to be examined is not expected to change significantly. Therefore, aberration correction can be performed with sufficient accuracy and precision even by referring to an aberration map, without having to perform aberration measurement and aberration correction amount calculation in parallel with scanning as in the conventional case.

Therefore, according to the present embodiment, a wide range of the posterior segment can be covered at high speed without causing problems such as increased processing load, increased complexity and cost of hardware and software, and complicated calculations and control. It is possible to apply optical scanning and obtain high quality images.

In this embodiment, the aberration map may record aberration correction amounts corresponding to each of a plurality of positions within a specific area. In the above example, the aberration map 219 in which scan positions are defined in a two-dimensional coordinate system (scan coordinate system) corresponds to "a plurality of positions" in this example.

Furthermore, the control unit controls the data collection unit to scan one of a plurality of positions in the specific area, and calculates the aberration based on the aberration correction amount corresponding to the one position recorded in the aberration map. The control of the correction unit may be configured to be executed in parallel.

In this embodiment, the data collection unit may include an optical scanner that deflects light for scanning the posterior segment of the eye. In the above example, the optical scanner includes optical scanner 44.

Further, the aberration map may record an aberration correction amount corresponding to each of a plurality of pieces of control information for the optical scanner. In the above example, a parameter indicating the direction of a deflection mirror (galvano mirror) included in the optical scanner 44 is used to define the scan position, or a parameter included in a signal for controlling the optical scanner 44 is used to define the scan position. This case corresponds to "a plurality of pieces of control information" in this example.

Furthermore, the control unit controls the optical scanner based on one of the plurality of control information and the aberration correction unit based on the aberration correction amount corresponding to the one control information recorded in the aberration map. May be configured to run in parallel.

In this embodiment, the specific area of the aberration map may include at least the peripheral area of the scan area.

Generally, the peripheral area of the scan area corresponds to a location away from the center of the fundus, and furthermore, the peripheral area of the wide-angle scan area corresponds to the peripheral part of the fundus. Therefore, scanning of the peripheral region is relatively significantly influenced by aberrations. By setting the specific area of the aberration map to include the peripheral area of the scan area, it becomes possible to effectively correct aberrations that occur during scanning of areas such as the peripheral part of the fundus where aberration correction is highly necessary.

In the present embodiment, the control unit controls the data collection unit in accordance with a scan pattern that includes a continuous first partial pattern for the center area of the scan area different from the peripheral area and a continuous second partial pattern for the peripheral area. , may be configured to be executed in conjunction with control of the aberration correction unit based on the aberration map.

According to this example, a scan pattern including a continuous first partial pattern for the central region and a continuous second partial pattern for the peripheral region can be applied. As mentioned above, the influence of aberrations is relatively small in the central part of the fundus, and the influence is relatively large in the peripheral part of the fundus. Therefore, by applying the scan pattern of this example, the aberration correction section can be easily controlled. More specifically, it is not necessary to change the aberration correction amount (largely) while the central region is continuously scanned, and it is not necessary to change the aberration correction amount (largely) while the peripheral region is continuously scanned. There is no need to change the aberration correction amount (largely), and it is sufficient to change the aberration correction amount (largely) only from the end of scanning the central region to the start of the peripheral region. On the other hand, when raster scanning is applied as in the past, the amount of aberration correction needs to be changed significantly between each B-scan, so the aberration correction section must be controlled extremely quickly.

In this embodiment, the scan pattern may include a curved scan pattern defined by a polar coordinate system with the origin at the center of the scan area.

In setting the curved scan pattern, for example, the structural characteristics and control characteristics of the optical scanner (44), the required scan speed, the required scan density, etc. can be taken into consideration.

In this embodiment, the curved scan pattern may be a spiral scan pattern (510) from the center of the scan area to the outer edge. Alternatively, the curved scan pattern may be a spiral scan pattern from the outer edge to the center of the scan area (520).

Another example of a curved scan pattern is a concentric scan pattern.

The ophthalmologic imaging apparatus (1) according to the present embodiment may include an image construction section that constructs an image from data collected by the data collection section. In the above example, the image construction unit includes the image construction unit 220.

The image constructor may form an image defined in a polar coordinate system (eg, an OCT image H ₁ ) from data collected by a scan applied to the posterior segment according to a curved scan pattern. Further, the image construction unit can convert an image defined in this polar coordinate system (e.g., OCT image H ₁ ) into an image defined in a three-dimensional orthogonal coordinate system (e.g., OCT image H ₂ (m)). .

According to such a configuration, it is possible to construct an image defined by a three-dimensional orthogonal coordinate system that allows image processing and analysis to be easily performed from an image obtained using a curved scan pattern.

The ophthalmologic imaging device (1) according to the present embodiment includes an imaging unit that repeatedly photographs an eye to be examined (E), and a movement detection unit that analyzes time-series images acquired by the imaging unit to detect movement of the eye to be examined. may further include. In this example, the imaging section includes the fundus camera unit 2, and the movement detection section includes the movement detection section 232.

The data collection unit may also include an optical scanner that deflects light for scanning the posterior segment of the eye. In this example, the optical scanner includes optical scanner 44 .

Furthermore, the control section may be configured to control the optical scanner based on the output from the movement detection section while controlling the data collection section and the aberration correction section in a coordinated manner. Here, the data collection unit and the optical scanner are controlled by the scan control unit 213, and the aberration correction unit is controlled by the aberration correction control unit 215.

According to such a configuration, it is possible to perform a wide-angle scan while performing tracking to correct the projection position of the scan light in accordance with the movement of the subject's eye. Thereby, even if the subject's eye moves during the wide-angle scan, it is possible to suitably perform the scan according to the wide-angle scan pattern. In addition, it is possible to avoid interrupting or redoing the scan.

In this embodiment, the storage unit may store in advance two or more maps corresponding to two or more diopter values. In this case, the control section can select a map corresponding to the diopter value of the subject's eye from among the two or more maps, and control the aberration correction section based on the selected map.

According to such a configuration, it is possible to correct aberrations during scanning using an aberration map that corresponds to the diopter of the eye to be examined, thereby making it possible to achieve even higher image quality.

In this embodiment, the data collection unit may include an OCT data collection unit that applies an OCT scan to the posterior segment of the eye and collects OCT data. In the above example, the OCT data collection unit connects the OCT unit 100 and the elements in the fundus camera unit 2 that constitute the measurement arm (retroreflector 41, OCT focusing lens 43, optical scanner 44, objective lens 22, etc.). include.

Further, the ophthalmologic imaging apparatus (1) according to the present embodiment may include an OCT image construction section that constructs an OCT image from OCT data collected by the OCT data collection section. In the above example, the OCT image construction unit includes an image construction unit 220.

Furthermore, the ophthalmologic imaging apparatus (1) according to the present embodiment may include a map creation section that creates an aberration map stored in the storage section based on the OCT image constructed by the OCT image construction section. In the above example, the map creation section includes an aberration map creation section 233.

With this configuration, aberrations can be corrected during scanning (optical scans such as OCT scans and SLO scans) using individual aberration maps depending on the eye to be examined, resulting in even higher image quality. It becomes possible to achieve this goal.

Exemplary embodiments provide a method of controlling an ophthalmological imaging device. An ophthalmologic imaging apparatus to which this control method is applied includes a data collection unit that collects data by scanning the posterior segment of an eye to be examined with light, and an aberration correction unit that corrects at least aberrations caused by the eye to be examined.

This control method includes a map preparation step and a control step. The map preparation step prepares a map representing the distribution of aberration correction amounts in a specific area that is at least a part of the scan area by the data collection unit. In the control step, control of a data collection unit for scanning a region of the posterior segment corresponding to a specific area and control of an aberration correction unit based on a map are executed in conjunction.

For such a method of controlling an ophthalmological imaging device, it is possible to combine any of the matters described in the exemplary embodiments.

The exemplary embodiment provides a program that causes a computer to execute such a control method. It is possible to combine any of the things described in the exemplary embodiments to this program.

Furthermore, it is possible to create a computer-readable non-temporary recording medium that records such a program. It is possible to combine any of the things described in the exemplary embodiments for this recording medium. Further, this non-temporary recording medium may be in any form, and examples include a magnetic disk, an optical disk, a magneto-optical disk, and a semiconductor memory.

According to the method, program, or recording medium according to the exemplary embodiment, it is possible to avoid problems such as increased processing load, increased complexity and cost of hardware and software, and complicated calculation and control. It is possible to apply high-speed optical scanning to a wide area of the body and obtain high-quality images. Further, operations and effects are produced depending on the methods, programs, or matters combined with the recording medium according to the exemplary embodiments.

The configurations described above are merely examples of embodiments of the invention. Therefore, any modification (omission, substitution, addition, etc.) can be made within the scope of the gist of the invention.

For example, the aberration correction unit is not limited to an aberration correction device as an optical element, and may be a processor and a program that can perform aberration correction by calculation, for example. Computational aberration correction is described, for example, in the following literature: S. A. Hojjatoleslami, M. R. N. Avanaki, and A. Gh. Podoleanu “Image quality improvement in optical coherence tomography using Lucy-Richardson deconvolution algorithm”, Applied Optics, Vol. 52 , Issue 23, pp.5663-5670 (2013).

In this case, the following modification example can be constructed. That is, the ophthalmologic imaging apparatus according to this modification includes a data collection section and an aberration correction section. The data collection unit collects data by scanning the posterior segment of the subject's eye with light. The aberration correction section includes a processor that operates according to a program, and corrects aberrations of the image based on the data collected by the data collection section. The image area to which the aberration correction section applies the aberration correction may be, for example, the same as a specific area in the aberration map.

Even in this modification, the same control method, program, and recording medium as in the above-described exemplary embodiment can be configured. It is also possible to combine any of the matters described in the exemplary embodiments to this variant.

1 Ophthalmic imaging apparatus 100 OCT unit 210 Control section 211 Main control section 212 Storage section 213 Scan control section 214 Focus control section 215 Aberration correction control section 219 Aberration map 220 Image construction section 230 Data processing section 231 Parameter setting section 232 Movement detection section 233 Aberration map creation section 240 User interface 241 Display section 242 Operation section

Claims (13)

a data collection unit that collects data by scanning with light a scan area including the central part of the fundus and the peripheral part of the fundus in the posterior segment of the subject's eye;
A map representing the distribution of the amount of aberration correction in a specific area that is at least a part of the scan area and includes the peripheral part of the fundus, wherein the amount of aberration correction is calculated from the aberration distribution statistically determined by measurements of multiple living eyes. a storage unit that stores in advance a map created by acquiring the distribution ;
an aberration correction unit that corrects at least aberrations caused by the eye to be examined;
an ophthalmologic imaging device comprising: a control unit that performs in conjunction a control of the data collection unit for scanning a region of the posterior eye segment corresponding to the specific area and control of the aberration correction unit based on the map; . The map records aberration correction amounts corresponding to each of a plurality of positions within the specific area,
The control unit controls the data collection unit to scan one of the plurality of positions, and the aberration correction unit based on the aberration correction amount corresponding to the one position recorded on the map. The ophthalmologic imaging apparatus according to claim 1, wherein the control is executed in parallel. The data collection unit includes an optical scanner that deflects light for scanning the posterior segment,
The map records an aberration correction amount corresponding to each of a plurality of pieces of control information for the optical scanner,
The control unit controls the optical scanner based on one control information among the plurality of control information, and the aberration correction unit based on an aberration correction amount corresponding to the one control information recorded in the map. The ophthalmologic imaging apparatus according to claim 1, wherein the control is executed in parallel. The ophthalmologic imaging apparatus according to any one of claims 1 to 3, wherein the specific area includes at least a peripheral area of the scan area. The control unit controls the data collection unit according to a scan pattern that includes a continuous first partial pattern for a central area of the scan area that is different from the peripheral area and a continuous second partial pattern for the peripheral area. 5. The ophthalmologic imaging apparatus according to claim 4, wherein the control is performed in conjunction with the control of the aberration correction unit based on the map. The ophthalmologic imaging apparatus according to claim 5, wherein the scan pattern includes a curved scan pattern defined by a polar coordinate system with the origin at the center of the scan area. 7. The curved scan pattern is either a spiral scan pattern extending from the center to the outer edge of the scan area or a spiral scan pattern extending from the outer edge to the center of the scan area. The ophthalmological imaging device described. further comprising an image construction unit that constructs an image from the data collected by the data collection unit,
The image construction unit is configured to form an image defined in the polar coordinate system from data collected by a scan applied to the posterior segment according to the curved scan pattern, and to form an image defined in the polar coordinate system. The ophthalmologic photographing apparatus according to claim 6 or 7, wherein the image is converted into an image defined by a three-dimensional orthogonal coordinate system. an imaging unit that repeatedly photographs the eye to be examined;
further comprising: a movement detection unit that analyzes time-series images acquired by the imaging unit to detect movement of the eye to be examined;
The data collection unit includes an optical scanner that deflects light for scanning the posterior segment,
The control unit controls the optical scanner based on the output from the movement detection unit while controlling the data collection unit and the aberration correction unit in a coordinated manner. The ophthalmological imaging device described in the above. The storage unit stores in advance two or more maps corresponding to two or more diopter values,
The control unit selects a map corresponding to the diopter value of the eye to be examined from among the two or more maps, and controls the aberration correction unit based on the selected map. The ophthalmologic imaging device according to any one of Items 1 to 9. A data collection unit that collects data by scanning with light a scan area including a central part of the fundus and a peripheral part of the fundus in the posterior segment of the eye to be examined, and an aberration correction unit that corrects at least aberrations caused by the eye to be examined. A method for controlling an ophthalmological imaging device, the method comprising:
A map representing the distribution of the amount of aberration correction in a specific area that is at least a part of the scan area and includes the peripheral part of the fundus, wherein the amount of aberration correction is calculated from the aberration distribution statistically determined by measurements of multiple living eyes. obtaining the distribution and preparing the created map ;
Ophthalmologic imaging, comprising: a control step of controlling the data collection unit for scanning a region of the posterior eye segment corresponding to the specific area, and controlling the aberration correction unit based on the map in a coordinated manner. How to control the device. A program that causes a computer to execute the method for controlling an ophthalmologic photographing apparatus according to claim 11 . A computer-readable non-transitory recording medium on which the program according to claim 12 is recorded.

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