JP2017169671A - Ophthalmologic imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ophthalmologic imaging apparatus capable of acquiring a wide-angle image in which visualization of a ghost is suppressed.SOLUTION: An ophthalmologic imaging apparatus includes an objective optical system and a scan system. The scan system is used for scanning the ocular fundus with a light flux through the objective optical system. The objective optical system includes an optical unit including a first optical member, and a second optical member arranged closer to a side of an eye to be examined than the first optical member, reflects the light flux that skews relative to an optical axis of the scan system and passes through a vicinity area of an optical axis in the first optical member at least twice, and irradiates it onto the ocular fundus through a vicinity area of an optical axis in the second optical member.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an ophthalmologic photographing apparatus.

  An ophthalmologic imaging apparatus for screening eye diseases and the like is required to be capable of easily imaging the fundus of the eye to be examined with a wide field of view. As such an ophthalmologic photographing apparatus, a scanning laser opthalmoscope (hereinafter referred to as SLO) is known. The SLO is an apparatus that forms an image of the fundus by scanning the fundus with light and detecting the return light with a light receiving device.

  For example, Patent Document 1 discloses an SLO that includes three optical scanners and controls them to perform a wide area scan and a scan that enlarges a part of the scan area.

Japanese Patent Laying-Open No. 2015-229023

  However, it is known that a ghost (noise) due to the surface reflection of the objective lens or the cornea of the eye to be examined is depicted in the center of an image acquired by an ophthalmologic photographing apparatus such as SLO. The size and light amount of the ghost increase as the angle of view increases. In many cases, a site of interest is arranged at the center of the acquired image, and if a ghost is depicted in the center, there may be a problem in diagnosis.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an ophthalmologic photographing apparatus capable of acquiring a wide-angle image in which ghost rendering is suppressed.

  The ophthalmologic photographing apparatus according to the embodiment includes an objective optical system and a scan system. The scan system is used to scan the fundus with a light beam via the objective optical system. The objective optical system includes an optical unit that includes a first optical member and a second optical member disposed closer to the eye to be inspected than the first optical member, and is skewed with respect to the optical axis of the scan system. The light beam that has passed through the region near the optical axis of the first optical member is reflected at least twice and irradiated to the fundus through the region near the optical axis of the second optical member.

  According to the present invention, it is possible to provide an ophthalmologic photographing apparatus capable of acquiring a wide-angle image in which ghost rendering is suppressed.

It is the schematic which shows an example of a structure of the optical system of the ophthalmologic imaging device which concerns on embodiment. It is the schematic which shows an example of a structure of the optical system of the ophthalmologic imaging device which concerns on embodiment. It is the schematic which shows an example of a structure of the optical system of the ophthalmologic imaging device which concerns on embodiment. It is the schematic which shows an example of a structure of the processing system of the ophthalmologic imaging device which concerns on embodiment. It is a flowchart of the 1st operation example of the ophthalmologic imaging device which concerns on embodiment. It is operation | movement explanatory drawing of the ophthalmologic imaging device which concerns on embodiment. It is operation | movement explanatory drawing of the ophthalmologic imaging device which concerns on embodiment. It is operation | movement explanatory drawing of the ophthalmologic imaging device which concerns on embodiment. It is operation | movement explanatory drawing of the ophthalmologic imaging device which concerns on embodiment. It is operation | movement explanatory drawing of the ophthalmologic imaging device which concerns on embodiment. It is a flowchart of the 2nd operation example of the ophthalmologic imaging device which concerns on embodiment. It is a flowchart of the 3rd operation example of the ophthalmologic imaging apparatus which concerns on embodiment. It is the schematic which shows an example of a structure of the optical system of the ophthalmologic imaging device which concerns on the 1st modification of embodiment. It is the schematic which shows an example of a structure of the optical system of the ophthalmologic imaging device which concerns on the 2nd modification of embodiment.

  An example of an embodiment of an ophthalmologic photographing apparatus according to the present invention will be described in detail with reference to the drawings. In addition, it is possible to use the description content of the literature referred in this specification, and arbitrary well-known techniques for the following embodiment.

  The ophthalmologic photographing apparatus according to the embodiment deflects light from a light source using an optical scanner, and irradiates the deflected light to a subject's eye (target eye, patient's eye), thereby receiving light through the pupil of the subject's eye. It is an apparatus that can irradiate a wide range of the posterior eye part (fundus, vitreous body, etc.) of the optometry. Such a configuration can be applied to any ophthalmologic photographing apparatus capable of irradiating light to the posterior eye portion. Ophthalmic imaging devices that can irradiate light to the posterior segment of the eye include laser treatment devices for irradiating the treatment site on the fundus with laser light, while moving the target with the eye fixed to the eye to be examined. A perimeter for measuring the visual field based on the response of the subject (patient) is included.

  In addition, the ophthalmologic photographing apparatus according to the embodiment forms predetermined data distribution (image, layer thickness distribution, lesion distribution, etc.) in the posterior eye portion by receiving the return light from the posterior eye portion of the eye to be examined. Is possible. Such a configuration can be applied to any ophthalmic imaging apparatus that can acquire data by scanning the posterior eye segment with light. The ophthalmologic photographing apparatus capable of acquiring data by scanning the posterior eye portion with light includes SLO for obtaining a front image of the fundus by laser scanning using a confocal optical system, and optical coherence tomography (hereinafter referred to as optical coherence tomography: There are an optical coherence tomography that obtains a tomographic image of the fundus using OCT), a multifunction machine that combines the function of SLO and the function of optical coherence tomography, and the like. Hereinafter, the case where the ophthalmologic imaging apparatus according to the embodiment has the function of SLO and the function of optical coherence tomography will be described.

  In the following description, it is assumed that the horizontal direction when viewed from the subject is the X direction, the vertical direction is the Y direction, and the depth direction of the optical system is the Z direction when viewed from the subject.

[Optical system]
FIG. 1 to FIG. 3 show configuration examples of the optical system of the ophthalmologic photographing apparatus according to the embodiment. The ophthalmologic imaging apparatus according to the embodiment can acquire an image of the eye to be examined in a range corresponding to the imaging mode. The ophthalmologic photographing apparatus can selectively arrange the objective optical unit corresponding to the photographing mode on the optical axis of the optical system.

  FIG. 1 shows a configuration example of an optical system of an ophthalmologic photographing apparatus when the high magnification (narrow angle (narrow angle of view)) photographing mode is set. FIG. 2 shows a configuration example of the objective optical system according to the embodiment that can be changed according to the photographing mode. In FIG. 2, the same parts as those in FIG. FIG. 3 shows a configuration example of the optical system of the ophthalmologic photographing apparatus when the wide-angle (wide-angle) photographing mode is set. In FIG. 3, the same parts as those in FIG. 1 or FIG. 1 and 3, a position optically conjugate with the fundus oculi Ef of the eye E is shown as a fundus conjugate position P, and a position optically conjugated with the pupil (pupil) of the eye E as a pupil conjugate position Q. It is shown in the figure.

  The optical system 100 includes a projection system that projects light onto the eye to be examined via the objective optical system 110, and a light receiving system that receives return light of the light projected onto the eye E through the projection system via the objective optical system 110. including. The ophthalmologic photographing apparatus forms an image based on the light reception result by the light receiving system. The ophthalmologic imaging apparatus according to the embodiment can form an SLO image and an OCT image. That is, the optical system 100 includes an SLO optical system 130 and an OCT optical system 140. The SLO optical system 130 includes an SLO projection system and an SLO light receiving system. The OCT optical system 140 includes an OCT projection system and an OCT light receiving system.

  The ophthalmologic imaging apparatus is provided with an anterior ocular segment imaging system (anterior ocular segment observation system) 120 for imaging the anterior segment of the eye to be examined. The optical system 100 can be moved in the X direction, the Y direction, and the Z direction by a moving mechanism (not shown) (moving mechanism 100D described later) together with the objective optical system 110 and the anterior eye photographing system 120. The ophthalmologic photographing apparatus moves the optical system 100 or the like by the moving mechanism based on the anterior eye image of the eye E to be examined obtained by the anterior eye photographing system 120, and thereby the position of the optical system 100 with respect to the eye E to be examined. It is possible to perform alignment for alignment. Hereinafter, a case where the optical system 100 includes the objective optical system 110 and the anterior ocular segment imaging system 120 will be described. However, the optical system 100 may be configured not to include these.

(Objective optical system)
The ophthalmologic photographing apparatus can selectively arrange the objective optical unit on the optical axis O of the optical system 100 according to the photographing mode. In this embodiment, the photographing mode includes a high-magnification photographing mode for photographing the eye E in a first range (for example, an angle of view of 50 degrees) and a second range wider than the first range (for example, an angle of view of 105 degrees). And a wide-angle photographing mode for photographing the eye E. In the high magnification imaging mode, a high magnification (narrow angle) image (SLO image or OCT image) representing the first range of the eye E is acquired. In the wide-angle imaging mode, a wide-angle image (SLO image or OCT image) representing a second range wider than the first range of the eye E is acquired. Hereinafter, an image acquired in the high-magnification shooting mode may be referred to as a “narrow-angle image” (“standard image”), and an image acquired in the wide-angle shooting mode may be referred to as a “wide-angle image”.

  The objective optical system 110 includes objective optical units 110A and 110B (see FIG. 2). The objective optical system 110 is provided with an angle-of-view changing mechanism 116 for changing the angle of view. The view angle changing mechanism 116 includes, for example, a known rotation mechanism or slide mechanism. In this embodiment, the objective optical unit 110B can be inserted into and removed from the optical axis O of the optical system 100 (the optical path of light from the optical system 100) by the angle-of-view changing mechanism 116. That is, the angle of view can be changed by selectively disposing the objective optical unit 110B between the objective optical unit 110A and the eye E by the angle-of-view changing mechanism 116 according to the imaging mode. In the high-magnification shooting mode, the objective optical unit 110A is arranged so that the optical axis thereof coincides with the optical axis of the optical system 100 (FIG. 1). In the wide-angle imaging mode, the objective optical units 110A and 110B are arranged between the objective optical unit 110A and the eye E so that the optical axis coincides with the optical axis O (FIG. 3). For example, by providing a detection unit that detects whether or not the objective optical unit 110B is arranged on the optical axis O in the objective optical system 110, the control unit 200 described later allows the objective optical unit 110B to be arranged on the optical axis O. The type of shooting mode can be specified from the presence / absence detection result. The angle-of-view changing mechanism 116 may automatically place the objective optical unit 110B on the optical axis O under the control of the control unit 200 described later. For example, the objective optical unit 110B may include a lens group corresponding to the objective optical unit 110A, and the objective optical unit 110A and the objective optical unit 110B may be selectively arranged according to the shooting mode.

  The objective optical unit 110A includes two or more lenses. A dichroic mirror DM1 is provided between the two or more lenses. For example, the objective optical unit 110A may be a lens unit (Nagler type) including convex lenses 111A and 112A and a concave lens 113A. The convex lenses 111A and 112A and the concave lens 113A are arranged in this order from the eye E side. A dichroic mirror DM1 is disposed between the convex lens 112A and the concave lens 113A. The dichroic mirror DM1 is an optical path coupling member that couples the optical path of the anterior ocular segment imaging system 120 to both the optical path of the SLO optical system 130 and the optical path of the OCT optical system 140. Between the dichroic mirror DM1 and the concave lens 113A, a position (fundus conjugate position) P optically conjugate with the fundus (retina) or its vicinity is disposed. The objective optical unit 110A may include a dichroic mirror DM1.

  The dichroic mirror DM1 receives light from the SLO optical system 130 (SLO light), return light from the eye E to be examined, light from the OCT optical system 140 (OCT light, measurement light), and return light from the eye E to be examined. Make it transparent. The dichroic mirror DM1 reflects the light from the anterior eye imaging system 120 toward the eye E, and reflects the return light from the eye E toward the anterior eye imaging system 120.

  The objective optical unit 110B includes a first spherical mirror 111B and a second spherical mirror 112B as optical elements of the reflective optical system. The first spherical mirror 111B is disposed closer to the eye E to be examined than the second spherical mirror 112B. An opening is formed in a region near the optical axis O in the first spherical mirror 111B (a central portion of the first spherical mirror 111B). On the surface of the first spherical mirror 111B on the optical system 100 side, a reflection surface that reflects the irradiated light toward the optical system 100 side is provided. An opening is formed in a region near the optical axis O in the second spherical mirror 112B (a central portion of the second spherical mirror 112B). On the surface of the second spherical mirror 112B on the eye E side, a reflecting surface that reflects the irradiated light toward the eye E is provided. Note that at least one of the reflecting surfaces of the first spherical mirror 111B and the second spherical mirror 112B may be an elliptical surface or a free-form surface instead of a spherical surface. In addition, a translucent part may be provided in the vicinity of the optical axis O in at least one of the first spherical mirror 111B and the second spherical mirror 112B.

  The light (SLO light, OCT light) that passes through the objective optical unit 110A, passes through the opening (region near the optical axis O) formed in the second spherical mirror 112B obliquely with respect to the optical axis O is the first. Reflected by the spherical mirror 111B toward the reflecting surface of the second spherical mirror 112B. The light reflected by the first spherical mirror 111B is applied to the fundus of the eye E through an opening (region near the optical axis O) formed in the first spherical mirror 111B by the second spherical mirror 112B. That is, the objective optical unit 110B is inclined at least with respect to the optical axis O and reflects light that has passed through a region near the optical axis O in the second spherical mirror 112B at least twice, and in the vicinity of the optical axis O in the first spherical mirror 111B. Irradiate the fundus through the area. The return light of the light irradiated on the fundus of the eye E is guided to the optical system 100 through the same path.

  Hereinafter, the case where only the objective optical unit 110A is arranged on the optical axis O as the objective optical system 110 will be mainly described.

(Anterior segment imaging system)
The anterior segment imaging system 120 includes an anterior segment illumination light source 121, a collimator lens 122, an anterior segment imaging camera 123, an imaging lens 124, and a beam splitter BS1. The beam splitter BS1 is an optical path coupling member that couples the optical path of the return light to the optical path of the illumination light for illuminating the anterior segment of the eye E.

  The anterior segment illumination light source 121 is a light source for illuminating the anterior segment of the eye E. The anterior segment imaging camera 123 includes an image sensor for detecting reflected light (return light) from the anterior segment of the eye E illuminated by the anterior segment illumination light source 121. As the anterior segment illumination light source 121, for example, an LED that emits light having a center wavelength of 950 nm is used. The light emitted from the anterior segment illumination light source 121 is converted into a parallel light beam by the collimator lens 122. The illumination light converted into a parallel light beam is reflected toward the dichroic mirror DM1 by the beam splitter BS1. The illumination light reflected by the beam splitter BS1 is deflected toward the eye E by the dichroic mirror DM1. The return light of the illumination light from the eye E is reflected by the dichroic mirror DM1 and passes through the beam splitter BS1. The return light that has passed through the beam splitter BS1 is condensed on the detection surface of the image sensor in the anterior segment imaging camera 123 by the imaging lens 124. The detection surface of the image sensor is disposed at or near the pupil conjugate position (anterior eye conjugate position) Q. The image sensor is constituted by, for example, a CCD or a CMOS image sensor. The detection result of the return light from the anterior eye part of the eye E to be examined by the image sensor is used to form an image of the anterior eye part.

(SLO optical system)
The optical path of the SLO optical system 130 and the optical path of the OCT optical system 140 are coupled by a dichroic mirror DM2. At least a part of the SLO optical system 130 is formed as a telecentric optical system. Similarly, at least a part of the OCT optical system 140 is formed as a telecentric optical system. The dichroic mirror DM2 couples an optical path formed by the telecentric optical system of the SLO optical system 130 and an optical path formed by the telecentric optical system of the OCT optical system 140. Thereby, even when the focal position of the optical system 100 is changed by the movement of the objective optical system 110, the aberration of the pupil (for example, the exit pupil by the objective optical system 110) is reduced, and the adjustment of the in-focus state is facilitated.

  The SLO optical system 130 includes an SLO light source 131, a collimating lens 132, a beam splitter BS2, a condenser lens 133, a confocal stop 134, a detector 135, an optical scanner 136, and a lens 137. The beam splitter BS2 is an optical path coupling member that couples the optical path of the return light to the optical path of the SLO light projected onto the eye E.

  As the SLO light source 131, for example, a light source that emits light having a center wavelength of 840 nm is used. Examples of the SLO light source 131 include a laser diode (hereinafter referred to as LD), a super luminescent diode (super luminescent diode: SLD), a laser driven light source (LDLS), and the like. The SLO light source 131 is disposed at or near a position (fundus conjugate position) P optically conjugate with the fundus (retina).

  The light emitted from the SLO light source 131 is converted into a parallel light beam by the collimator lens 132. The light converted into the parallel light flux passes through the beam splitter BS2. The light transmitted through the beam splitter BS2 is deflected by the optical scanner 136. The optical scanner 136 is used for scanning the fundus oculi Ef of the eye E with the light from the SLO light source 131. The optical scanner 136 includes an optical scanner 136X that deflects light in the X direction and an optical scanner 136Y that deflects light in the Y direction. The optical scanner 136X is a mirror whose tilt can be changed, and the tilt of the reflection surface is controlled by the control unit 200 described later. The optical scanner 136 is used for, for example, horizontal scanning within the fundus. An optical scanner 136Y is disposed on the eye E side of the optical scanner 136X. The optical scanner 136Y is a mirror whose tilt can be changed, and the tilt of the reflecting surface is controlled by the control unit 200. The optical scanner 136Y is used, for example, for scanning in the vertical direction within the fundus oculi orthogonal to the horizontal direction. One of the optical scanner 136X and the optical scanner 136Y is a low-speed scanner such as a galvanometer mirror, and the other is a high-speed scanner such as a resonant mirror, a polygon mirror, or a MEMS (Micro Electro Mechanical Systems: hereinafter, MEMS) mirror. It's okay. The reflection surface of the optical scanner 136Y is disposed at a position (pupil conjugate position) Q that is optically conjugate with the pupil of the eye E or at the vicinity thereof. A lens 137 and a dichroic mirror DM2 are arranged on the eye E side of the optical scanner 136Y. The light from the SLO light source 131 deflected by the optical scanner 136 passes through the lens 137 and the dichroic mirror DM2, and is projected onto the eye E through the objective optical system 110.

  The return light of the light from the SLO light source 131 projected onto the eye E is reflected toward the detector 135 by the beam splitter BS2 via the same optical path. A condensing lens 133 and a confocal stop 134 are disposed between the beam splitter BS2 and the detector 135. The condensing lens 133 condenses the light reflected by the beam splitter BS2. The light condensed by the condensing lens 133 passes through the opening formed in the confocal stop 134 and enters the detection surface of the detector 135. The aperture formed in the confocal stop 134 is disposed at or near a position P (fundus conjugate position) optically conjugate with the fundus (retina). The detector 135 is composed of, for example, an avalanche photodiode (APD) or a photomultiplier tube (PMT).

(OCT optical system)
The OCT optical system 140 includes a focusing lens 141, an optical scanner 142, a collimating lens 143, and an interference optical system 150. The interference optical system 150 includes an OCT light source 151, fiber couplers 152 and 153, a prism 154, and a detector 155.

  The focusing lens 141 can be moved along the optical axis (optical path) of the OCT optical system 140 by a moving mechanism (not shown) (moving mechanism 141D described later). Thereby, the focal position of the OCT optical system 140 can be changed independently of the SLO optical system 130. Therefore, for example, after the focus state of the SLO optical system 130 and the OCT optical system 140 is adjusted by the movement of the objective optical system 110, the focus state of the OCT optical system 140 is finely adjusted by the movement of the focusing lens 141. Can do.

  The optical scanner 142 is used to scan the fundus oculi Ef of the eye E with measurement light based on the light from the OCT light source 151. The optical scanner 142 includes an optical scanner 142X that deflects light in the X direction and an optical scanner 142Y that deflects light in the Y direction. The optical scanner 142X is a mirror whose tilt can be changed, and the tilt of the reflecting surface is controlled by the control unit 200. The optical scanner 142 is used, for example, for scanning in the horizontal direction within the fundus. An optical scanner 142Y is arranged on the eye E side of the optical scanner 142X. The optical scanner 142Y is a mirror whose tilt can be changed, and the tilt of the reflecting surface is controlled by the control unit 200. The optical scanner 142Y is used, for example, for scanning in the vertical direction within the fundus oculi orthogonal to the horizontal direction. One of the optical scanner 142X and the optical scanner 142Y may be a low-speed scanner such as a low-speed galvanometer mirror, and the other may be a high-speed scanner such as a high-speed galvanometer mirror. An intermediate position between the optical scanners 142X and 142Y is disposed at a position (pupil conjugate position) Q that is optically conjugate with the pupil of the eye E or a vicinity thereof. A collimating lens 143 is disposed on the OCT light source 151 side of the optical scanner 142Y.

  The interference optical system 150 is provided with an optical system for acquiring an OCT image of the eye E. This optical system has the same configuration as a conventional swept source type OCT apparatus. That is, this optical system divides the light from the wavelength sweep type (wavelength scanning type) light source into the measurement light and the reference light, and returns the return light of the measurement light from the eye E and the reference light via the reference light path. An interference optical system that generates interference light by causing interference and detects the interference light. The detection result (detection signal) of the interference light by the interference optical system is a signal indicating the spectrum of the interference light. The interference optical system 150 may have a configuration similar to that of a conventional spectral domain type OCT apparatus, not a swept source type OCT apparatus.

  The OCT light source 151 is a wavelength sweep type (wavelength scanning type) light source capable of sweeping (scanning) the wavelength of OCT light (emitted light). As the wavelength sweep type light source, for example, a laser light source including a resonator and emitting light having a center wavelength of 1050 nm is used. The OCT light source 151 temporally changes the output wavelength in a near-infrared wavelength band that cannot be visually recognized by the human eye.

  The light L0 output from the OCT light source 151 is guided to the fiber coupler 152 by the optical fiber f1, and is divided into the measurement light LS and the reference light LR.

  The reference light LR is guided to the fiber exit end c1 by the optical fiber f2, and is irradiated to the collimator lens 156 from the fiber exit end c1. The reference light LR emitted from the fiber exit end c1 is converted into a parallel light beam by the collimator lens 156. The reference light LR converted into a parallel light beam is guided to the prism 154. The prism 154 folds the traveling direction of the reference light LR made into a parallel light beam by the collimating lens 156 in the reverse direction. The optical path of the reference light LR incident on the prism 154 and the optical path of the reference light LR emitted from the prism 154 are parallel. The prism 154 is movable in a direction along the incident optical path and the outgoing optical path of the reference light LR by a moving mechanism (not shown) (moving mechanism 154D described later). In this case, an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force are provided. The actuator is constituted by, for example, a pulse motor. The transmission mechanism is configured by, for example, a combination of gears, a rack and pinion, or the like. Thereby, the length of the optical path of the reference light LR is changed.

  The reference light LR that has passed through the prism 154 is converted from a parallel light beam into a focused light beam by the collimator lens 157, enters the fiber incident end c2, and is guided to the fiber coupler 153 by the optical fiber f3. An optical path length correcting member or a dispersion compensating member may be disposed between the collimating lenses 156 and 157 and the prism 154. The optical path length correction member functions as a delay unit for matching the optical path length (optical distance) of the reference light LR with the optical path length of the measurement light LS. The dispersion compensation member functions as a dispersion compensation means for matching the dispersion characteristics between the reference light LR and the measurement light LS.

  On the other hand, the measurement light LS generated by the fiber coupler 152 is guided to the fiber end c3 by the optical fiber f4. The measurement light LS guided to the fiber end c3 is applied to the collimator lens 143. The fiber end c3 is disposed at a position (fundus conjugate position) P optically conjugate with the fundus (retina) or in the vicinity thereof. The measurement light LS emitted from the fiber end c3 is converted into a parallel light beam by the collimator lens 143. The measurement light LS converted into the parallel light beam reaches the dichroic mirror DM2 via the optical scanner 142 and the focusing lens 141. The measurement light LS is reflected by the dichroic mirror DM2, refracted by the objective optical system 110, and irradiated to the eye E. The measurement light LS is scattered (including reflection) at various depth positions of the eye E. The return light of the measurement light LS including such backscattered light travels in the reverse direction on the same path as the forward path, is guided to the fiber coupler 152, and reaches the fiber coupler 153 via the optical fiber f5.

  The fiber coupler 153 generates interference light by combining (interfering) the measurement light LS incident via the optical fiber f5 and the reference light LR incident via the optical fiber f3. The fiber coupler 153 generates a pair of interference light LC by branching the interference light between the measurement light LS and the reference light LR at a predetermined branching ratio (for example, 1: 1). The pair of interference lights LC emitted from the fiber coupler 153 is guided to the detector 155.

  The detector 155 is, for example, a balanced photodiode that includes a pair of photodetectors that detect a pair of interference lights LC and outputs a difference between detection results obtained by the pair of photodetectors. The detector 155 sends the detection result (detection signal) to a DAQ (Data Acquisition System) (not shown). A clock is supplied to the DAQ from the OCT light source 151. This clock is generated in synchronization with the output timing of each wavelength swept (scanned) within a predetermined wavelength range by the wavelength sweep type light source in the OCT light source 151. Based on this clock, the DAQ samples the detection result of the detector 155 and sends it to an image forming unit, which will be described later. The image forming unit forms a reflection intensity profile in each A line by performing Fourier transform or the like on the spectrum distribution based on the detection result obtained by the detector 155 for each series of wavelength scans (for each A line), for example. To do. Further, the image forming unit forms image data by imaging the reflection intensity profile of each A line.

[Processing system]
FIG. 4 shows a configuration example of a processing system of the ophthalmologic photographing apparatus according to the embodiment. 4, parts that are the same as those in FIGS. 1 and 3 are given the same reference numerals, and descriptions thereof will be omitted as appropriate.

(Control part)
The processing system of the ophthalmologic photographing apparatus according to the embodiment is configured around the control unit 200. The control unit 200 controls each unit of the ophthalmologic photographing apparatus. The control unit 200 includes a main control unit 201 and a storage unit 202. The function of the main control unit 201 is realized by a microprocessor, for example. The storage unit 202 stores in advance a computer program for controlling the ophthalmologic photographing apparatus. This computer program includes various light source control programs, optical scanner control programs, various detector control programs, image formation programs, data processing programs, user interface programs, and the like. When the main control unit 201 operates according to such a computer program, the control unit 200 executes control processing.

  Control for the objective optical system 110 includes control for a moving mechanism 110D that moves the objective optical system 110 along the optical axis O. For example, the moving mechanism 110D is provided with an actuator that generates a driving force for moving the moving mechanism 110D and a transmission mechanism that transmits the driving force. The actuator is constituted by, for example, a pulse motor. The transmission mechanism is configured by, for example, a combination of gears, a rack and pinion, or the like. The main control unit 201 controls the moving mechanism 110D by sending a control signal to the actuator.

  Controls for the SLO optical system 130 include control of the SLO light source 131, control of the optical scanner 136, control of the detector 135, and the like. Control of the SLO light source 131 includes turning on / off the light source, adjusting the light amount, adjusting the aperture, and the like. Control of the optical scanner 136 includes control of the scanning position and scanning range by the optical scanner 136X, control of the scanning position and scanning range by the optical scanner 136Y, and the like. The control of the detector 135 includes exposure adjustment of the detection element, gain adjustment, detection rate adjustment, and the like.

  Controls for the OCT optical system 140 include control of the OCT light source 151, control of the optical scanner 142, control of the moving mechanism 141D and the moving mechanism 154D, and control of the detector 155. Control of the OCT light source 151 includes turning on and off the light source, adjusting the light amount, adjusting the aperture, and the like. Control of the optical scanner 142 includes control of the scanning position and scanning range by the optical scanner 142X, control of the scanning position and scanning range by the optical scanner 142Y, and the like. The moving mechanism 141D moves the focusing lens 141 along the optical path of the OCT optical system 140. For example, the moving mechanism 141D is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The actuator is constituted by, for example, a pulse motor. The transmission mechanism is configured by, for example, a combination of gears, a rack and pinion, or the like. The main control unit 201 controls the moving mechanism 141D by sending a control signal to the actuator. The moving mechanism 154D moves the prism 154 in a direction along the incident optical path and the outgoing optical path of the reference light LR. For example, the moving mechanism 154D is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The actuator is constituted by, for example, a pulse motor. The transmission mechanism is configured by, for example, a combination of gears, a rack and pinion, or the like. The main control unit 201 controls the moving mechanism 154D by sending a control signal to the actuator. Control of the detector 155 includes exposure adjustment, gain adjustment, and detection rate adjustment of the detection element.

  Controls for the anterior segment imaging system 120 include control of the anterior segment illumination light source 121 and control of the anterior segment imaging camera 123. Control of the anterior segment illumination light source 121 includes turning on and off the light source, adjusting the light amount, adjusting the aperture, and the like. The control of the anterior eye photographing camera 123 includes exposure adjustment, gain adjustment, and photographing rate adjustment of the image sensor.

  Control for the optical system 100 includes control of a moving mechanism 100D that moves the optical system 100 (including the dichroic mirror DM1 and the anterior eye photographing system 120) in the X, Y, and Z directions. For example, the moving mechanism 100D is provided with an actuator that generates a driving force for moving the moving mechanism, and a transmission mechanism that transmits the driving force. The actuator is constituted by, for example, a pulse motor. The transmission mechanism is configured by, for example, a combination of gears, a rack and pinion, or the like. The main control unit 201 controls the moving mechanism 100D by sending a control signal to the actuator.

  The main control unit 201 includes an alignment control unit 201A, a tracking control unit 201B, and a display control unit 201C.

  The alignment control unit 201 </ b> A controls execution of alignment for aligning the optical system 100 with respect to the eye E. The alignment control unit 201A controls the movement mechanisms 100D and 110D based on the anterior segment image of the eye E obtained by the anterior segment imaging system 120. The alignment control unit 201A specifies, for example, a characteristic part in the anterior eye part image of the eye E obtained by the anterior eye photographing system 120, and a deviation amount between the position of the specified characteristic part and a predetermined target position The amount of movement of the optical system 100 or the like is obtained so that is canceled. The alignment control unit 201A aligns the optical system 100 with respect to the eye E by controlling the movement mechanism 100D based on the obtained movement amount (XY direction). The target position may be a predetermined position, or may be a position in the anterior ocular segment image specified using the UI unit 230.

  The alignment control unit 201A specifies, for example, the in-focus state (blurring condition) of the anterior eye image of the eye E obtained by the anterior eye imaging system 120, and the specified in-focus state is the desired in-focus state. It is possible to determine the amount of movement of the optical system 100 in the Z direction so that The alignment control unit 201A controls the movement mechanism 100D based on the obtained movement amount, thereby aligning the optical system 100 with respect to the eye E (Z direction). In addition, the anterior eye part is imaged from two different directions using two or more cameras, the in-focus state is specified three-dimensionally from two or more images provided with parallax, and the specified in-focus state is desired. The amount of movement of the optical system 100 in the Z direction may be obtained so as to be in focus.

  The alignment control unit 201A may perform alignment (Z direction) of the objective optical system 110 with respect to the eye E by controlling the moving mechanism 110D based on the SLO image obtained by the SLO optical system 130. In this case, the alignment control unit 201A specifies the in-focus state (blurring degree) of the acquired SLO image, and the objective optical system 110 in the Z direction so that the specified in-focus state becomes a desired in-focus state. Find the amount of movement. The alignment control unit 201A controls the movement mechanism 110D based on the obtained movement amount.

  The tracking control unit 201 </ b> B controls tracking of the eye E to be examined obtained by the SLO optical system 130 with respect to the SLO image. For example, the tracking control unit 201B specifies a feature part in the SLO image at a predetermined timing, and when the position of the specified feature part changes, obtains a movement amount so that the shift amount of the position is canceled. The tracking control unit 201B controls tracking for the SLO image based on the obtained movement amount.

  Further, the tracking control unit 201B controls tracking of the eye E to be examined obtained by the OCT optical system 140 with respect to the OCT image based on the SLO image. For example, the tracking control unit 201B specifies a feature part in the SLO image at a predetermined timing, and when the position of the specified feature part changes, obtains a movement amount so that the shift amount of the position is canceled. The tracking control unit 201B controls tracking for the OCT image based on the obtained movement amount. The tracking control unit 201B may be provided in the data processing unit 220.

  The display control unit 201C displays various types of information on the UI unit 230 described later. The information displayed on the UI unit 230 includes information generated by the control unit 200, an image formed by the image forming unit 210, information after data processing by the data processing unit 220, and the like.

  The display control unit 201C causes the UI unit 230 to display a composite image obtained by combining a wide-angle image and a narrow-angle image by an image composition unit 220C described later. The wide-angle image is an image (SLO image, OCT image) acquired in the wide-angle imaging mode as described above. As described above, the narrow-angle image is an image (SLO image, OCT image) acquired in the high-magnification imaging mode.

  The display control unit 201 </ b> C can display a composite image as a still image on the UI unit 230 or repeatedly display a composite image as a moving image on the UI unit 230. The composite image as a moving image includes an image in which only a narrow-angle image in the composite image is updated, and an image in which only a wide-angle image in the composite image is updated. For example, when a narrow-angle image is repeatedly acquired after a wide-angle image is acquired using the SLO optical system 130 or the OCT optical system 140, the narrow-angle image in the composite image is updated to the newly acquired narrow-angle image. The Alternatively, when the wide-angle image is repeatedly acquired after the narrow-angle image is acquired using the SLO optical system 130 or the OCT optical system 140, the wide-angle image in the composite image is updated to the newly acquired wide-angle image.

(Image forming part)
Image forming unit 210 includes an SLO image forming unit 210A and an OCT image forming unit 210B. The SLO image forming unit 210 </ b> A forms image data of an SLO image based on the detection signal input from the detector 135 and the pixel position signal input from the control unit 200. The OCT image forming unit 210B forms image data of an OCT image (a tomographic image of the fundus oculi Ef) based on the detection signal input from the detector 155 and the pixel position signal input from the control unit 200. The image forming unit 210 forms an anterior ocular segment image based on the detection result of the reflected light from the anterior segment of the eye E to be examined by the imaging element of the anterior segment imaging camera 123. Various images (image data) formed by the image forming unit 210 are stored in the storage unit 202, for example.

(Data processing part)
The data processing unit 220 executes various data processing. As an example of data processing, there is processing for image data formed by the image forming unit 210 or another device. Examples of this processing include various types of image processing, image analysis processing, and diagnostic support processing such as image evaluation based on image data.

  The data processing unit 220 includes an alignment unit 220A, a scale adjustment unit 220B, and an image composition unit 220C.

  The alignment unit 220A performs alignment between the wide-angle image of the eye E acquired in the wide-angle imaging mode and the narrow-angle image of the eye E acquired in the high-magnification imaging mode and including the center portion of the wide-angle image. The central part of the wide-angle image is a part including the position on the optical axis O. The wide-angle image is formed by a wide-angle (second range) SLO image or OCT image forming unit 210B formed by the SLO image forming unit 210A in the wide-angle shooting mode (a state where the objective optical unit 110B is inserted in the optical axis O). It is a wide-angle OCT image. The narrow-angle image is a narrow-angle (first range) SLO image or OCT image forming unit 210B formed by the SLO image forming unit 210A in the high-magnification shooting mode (a state in which the objective optical unit 110B is retracted from the optical axis O). Is a narrow-angle OCT image formed by

  The alignment unit 220A specifies, for example, a corresponding region of the wide-angle image corresponding to the central region including the central part of the narrow-angle image. The alignment unit 220A can specify the corresponding region based on the angle of view of each of the wide-angle image and the narrow-angle image and the position of the central region including the central portion of the wide-angle image. The alignment unit 220A performs alignment between the corresponding region in the wide-angle image and the narrow-angle image. In addition, the alignment unit 220A identifies a feature part (feature part such as a nipple or blood vessel) of the fundus oculi Ef that is drawn in common to the wide-angle image and the narrow-angle image, and uses the identified feature part as an index to wide angle. It is also possible to align the image and the narrow-angle image.

  The scale adjustment unit 220B determines whether the wide-angle image and the narrow-angle image that have been aligned by the alignment unit 220A based on the angle of view set in the wide-angle shooting mode and the angle of view set in the high-magnification shooting mode. Perform processing to match the scales.

  The image synthesis unit 220C forms a synthesized image by synthesizing the wide-angle image and the narrow-angle image that have been scale-adjusted by the scale adjustment unit 220B. The image composition unit 220C uses a central region (region including the central portion, partial region) of the wide-angle image including the position on the optical axis O of the optical system 100 as at least a partial region of the narrow-angle image corresponding to the central region. A composite image can be formed by replacement. For example, the image composition unit 220C forms a composite image by cutting out the corresponding area in the wide-angle image specified as described above and arranging at least a part of the narrow-angle image in the corresponding area. That is, the area including the central portion of the wide-angle image is replaced with at least a partial area of the narrow-angle image corresponding to the area. The wide-angle image is an image of a peripheral portion that is a peripheral region of the central portion because the central portion is not imaged. Therefore, by replacing the area including the central portion of the wide-angle image with at least a part of the narrow-angle image corresponding to the area, it is possible to acquire a wide-angle image in which ghost is suppressed. In addition, the resolution at the center of the wide-angle image is improved.

  The image composition unit 220C forms a composite image by superimposing at least a partial region of the narrow-angle image corresponding to the central region on the central region of the wide-angle image including the position on the optical axis O of the optical system 100. Is possible. For example, the image composition unit 220C forms a composite image by superimposing at least a part of the narrow-angle image on the corresponding region in the wide-angle image specified as described above. That is, at least a part of the narrow-angle image corresponding to the region is superimposed on the region including the center of the wide-angle image. Also in this case, it is possible to acquire a wide-angle image in which ghosts are suppressed. In addition, the resolution at the center of the wide-angle image is improved.

  That is, the image compositing unit 220C is a composite image in which the central portion of the wide-angle SLO image is replaced with the narrow-angle SLO image, the composite image in which the narrow-angle SLO image is superimposed on the central portion of the wide-angle SLO image, A composite image in which the central portion of the OCT image is replaced with the narrow-angle OCT image or a composite image in which the narrow-angle OCT image is superimposed on the central portion of the wide-angle OCT image is formed. In addition, the image composition unit 220C is a composite image in which the central portion of the wide-angle SLO image is replaced with the narrow-angle OCT image, the composite image in which the narrow-angle OCT image is superimposed on the central portion of the wide-angle SLO image, and the wide-angle SLO image. A composite image in which the central portion of the OCT image is replaced with a narrow-angle SLO image, or a composite image in which the narrow-angle SLO image is superimposed on the central portion of the wide-angle OCT image may be formed.

  Note that the alignment unit 220A performs alignment between the wide-angle image and the narrow-angle image adjusted so that the scales match, and the image composition unit 220C combines the aligned wide-angle image and narrow-angle image. You may form the synthesized image from which the ghost of the center part was removed by synthesize | combining.

  As described above, the image composition unit 220C includes the wide-angle image formed by the image forming unit 210 based on the data collected by the optical system 100 with the objective optical unit 110B inserted into the optical axis O, and the optical axis O. Then, based on the data collected by the optical system 100 with the objective optical unit 110B retracted, the narrow angle image formed by the image forming unit 210 is combined to form a combined image. The image composition unit 220C can form a composite image in which the narrow-angle image is arranged in the center and the wide-angle image is arranged in the periphery.

(UI part)
A UI (User Interface) unit 230 has a function for exchanging information between the user and the ophthalmologic photographing apparatus. The UI unit 230 includes a display device and an operation device (input device). The display device may include a display unit and may include other display devices. The operation device includes various hardware keys and / or software keys. The control unit 200 can receive an operation content for the operation device and output a control signal corresponding to the operation content to each unit. It is possible to integrally configure at least a part of the operation device and at least a part of the display device. A touch panel display is an example.

  The optical system 100 is an example of a “scan system” according to the embodiment. The objective optical unit 110B is an example of an “optical unit” according to the embodiment. The second spherical mirror 112B is an example of the “first optical member” according to the embodiment. The first spherical mirror 111B is an example of a “second optical member” according to the embodiment. The wide-angle image obtained by photographing the eye E when the wide-angle photographing mode is set is an example of the “first image” according to the embodiment. The narrow-angle image obtained by photographing the eye E when set to the high-magnification photographing mode is an example of the “second image” according to the embodiment.

[Operation]
An operation of the ophthalmologic photographing apparatus according to the embodiment will be described.

“First operation example”
5 and 6A to 6E show a first operation example of the ophthalmologic photographing apparatus according to the embodiment. FIG. 5 shows a flowchart of an operation example of the ophthalmologic photographing apparatus when acquiring an SLO image. 6A to 6E are operation explanatory views of the ophthalmologic photographing apparatus according to the embodiment of FIG.

(S1)
First, the objective optical unit 110B, which is a wide-angle objective lens, is inserted into the optical axis O by the angle-of-view changing mechanism 116. For example, a user such as an examiner, a subject, a doctor, or a patient manually inserts the objective optical unit 110B into the optical axis O. The ophthalmologic photographing apparatus can shift to the next operation based on an operation performed on the UI unit 230 by the user. The ophthalmologic photographing apparatus detects whether or not the objective optical unit 110B is arranged on the optical axis O, and when it is determined that the objective optical unit 110B is arranged on the optical axis O based on the detection result, the following operation is performed. You may make it transfer to.

  When the objective optical unit 110B is inserted into the optical axis O, the control unit 200 acquires an anterior segment image by capturing the anterior segment of the eye E with the anterior segment imaging system 120. The alignment control unit 201A controls the movement mechanism 100D based on the acquired anterior segment image, thereby aligning the optical system 100 and the objective optical system 110 with respect to the eye E (X direction, Y direction, and Z direction). direction). The control unit 200 moves the optical scanner 136 to a predetermined initial position. In S1, the tracking control unit 201B may start tracking control for the SLO image.

(S2)
The control unit 200 turns on the SLO light source 131 and controls the optical scanner 136 to start scanning the fundus oculi Ef of the eye E with the light from the SLO light source 131. The SLO image forming unit 210A forms an SLO image of the fundus oculi Ef based on the detection result of the fundus reflected light by the detector 135. The SLO image obtained in S2 is a wide-angle image as shown in FIG. 6A. The fundus oculi Ef is not drawn in the center G of this wide-angle image (it is difficult to observe the fundus oculi Ef).

(S3)
Next, the objective optical unit 110B is retracted from the optical axis O by the angle-of-view changing mechanism 116. For example, a user such as an examiner, a subject, a doctor, or a patient manually retracts the objective optical unit 110B from the optical axis O. When the objective optical unit 110B is retracted from the optical axis O, as in S1, the control unit 200 performs alignment and moves the optical scanner 136 to a predetermined initial position.

(S4)
When only the objective optical unit 110A is arranged on the optical axis O, the control unit 200 performs alignment again, and controls the optical scanner 136 in the same manner as in S2, thereby controlling the eye to be examined with the light from the SLO light source 131. A scan of the fundus oculi Ef of E is started. At this time, it is set so that the region including the central portion of the SLO image acquired in S2 is scanned. The SLO image forming unit 210A forms an SLO image of the fundus oculi Ef based on the detection result of the fundus reflected light by the detector 135. The SLO image obtained in S4 is a narrow-angle image as shown in FIG. 6B. A ghost is not drawn at the center of the narrow-angle image (or the ghost is hardly noticeable).

(S5)
Subsequently, as illustrated in FIG. 6C, the alignment unit 220 </ b> A converts the SLO image (narrow-angle image) of the eye E acquired in S <b> 4 in the SLO image (wide-angle image) of the eye E acquired in S <b> 2. A corresponding area (corresponding area) C1 is specified. As described above, the alignment unit 220A performs alignment between the SLO image (wide-angle image) of the eye E acquired in S2 and the SLO image (narrow-angle image) of the eye E acquired in S4. .

  The scale adjustment unit 220B determines whether the wide-angle image and the narrow-angle image that have been aligned by the alignment unit 220A based on the angle of view set in the wide-angle shooting mode and the angle of view set in the high-magnification shooting mode. Match the scales. In FIG. 6D, the scale of the narrow-angle image acquired in S4 is adjusted so as to match the scale of the wide-angle image acquired in S2. At this time, the scale adjustment unit 220B (data processing unit 220) can perform known distortion correction processing and color correction processing on at least one of the wide-angle image and the narrow-angle image. As shown in FIG. 6E, the image composition unit 220C combines the wide-angle image and the narrow-angle image that have been scale-adjusted by the scale adjustment unit 220B to remove (or suppress) the ghost in the center. Form. For example, the image composition unit 220C forms a composite image by replacing the central region of the wide-angle image with at least a partial region of the narrow-angle image corresponding to the central region.

(S6)
The display control unit 201C causes the UI unit 230 to display the composite image formed in S5.

(S7)
The control unit 200 determines whether or not the user can diagnose the eye E based on the composite image displayed in S6. The user confirms the composite image displayed on the UI unit 230 and instructs the UI unit 230 whether diagnosis is possible. The control unit 200 can determine whether or not diagnosis is possible based on the user's operation content on the UI unit 230. When it is determined that the diagnosis is possible (S7: Y), the operation of the ophthalmologic photographing apparatus ends (end). When it is determined that the diagnosis is not possible (S7: N), the operation of the ophthalmologic photographing apparatus proceeds to S8.

(S8)
When it is determined that the diagnosis is not possible (S7: N), the display control unit 201C receives the user's predetermined operation on the UI unit 230, and the display control unit 201C acquires the SLO image (narrow angle image) of the eye E acquired in S4. Is enlarged and displayed on the UI unit 230. Thereafter, the operation of the ophthalmologic photographing apparatus ends (END).

“Second operation example”
5 and 6A to 6E have described the case where the wide-angle SLO image and the narrow-angle SLO image are combined, but the same applies to the case where the wide-angle OCT image and the narrow-angle OCT image are combined.

  FIG. 7 shows a second operation example of the ophthalmologic photographing apparatus according to the embodiment. FIG. 7 shows a flowchart of an operation example of the ophthalmologic photographing apparatus when acquiring an OCT image.

(S11)
First, similarly to S1, the objective optical unit 110B, which is a wide-angle imaging objective lens, is inserted into the optical axis O by the angle-of-view changing mechanism 116. For example, a user such as an examiner, a subject, a doctor, or a patient manually inserts the objective optical unit 110B into the optical axis O.

  When the objective optical unit 110B is inserted into the optical axis O, the control unit 200 acquires an anterior segment image by capturing the anterior segment of the eye E with the anterior segment imaging system 120. The alignment control unit 201A controls the movement mechanism 100D based on the acquired anterior segment image, thereby aligning the optical system 100 and the objective optical system 110 with respect to the eye E (X direction, Y direction, and Z direction). direction). The control unit 200 moves the optical scanner 142 to a predetermined initial position.

  Next, the alignment control unit 201A performs alignment in the focus direction of the retina from the anterior segment image obtained by the anterior segment imaging system 120 or the SLO image obtained separately. Thereby, the position of the objective optical system 110 in the direction of the optical axis O can be finely adjusted.

  Subsequently, the main control unit 201 changes the focal position of the OCT optical system 140 based on the interference light detection signal obtained by the OCT optical system 140. For example, the main control unit 201 changes the focal position of the OCT optical system 140 by controlling the moving mechanism 141D so that the amplitude of the detection signal of predetermined interference light is maximized.

  In S11, the tracking control unit 201B may start tracking control for the OCT image.

(S12)
The control unit 200 turns on the OCT light source 151 and controls the optical scanner 142 to start scanning the fundus oculi Ef of the eye E with the measurement light LS based on the light from the OCT light source 151. The OCT image forming unit 210B forms an OCT image of the fundus oculi Ef based on the detection result of the interference light by the detector 155. The OCT image obtained in S12 is a wide-angle image. The fundus oculi Ef is not drawn at the center of the wide-angle image (it is difficult to observe the fundus oculi Ef).

(S13)
Next, the objective optical unit 110B is retracted from the optical axis O by the angle-of-view changing mechanism 116. For example, a user such as an examiner, a subject, a doctor, or a patient manually retracts the objective optical unit 110B from the optical axis O. When the objective optical unit 110B is retracted from the optical axis O, as in S11, the control unit 200 performs alignment and moves the optical scanner 142 to a predetermined initial position.

(S14)
When only the objective optical unit 110A is arranged on the optical axis O, the control unit 200 performs alignment again, and controls the optical scanner 142 as in S12 to control the fundus of the eye E with the measurement light LS. Ef scanning is started. The OCT image forming unit 210B forms an OCT image of the fundus oculi Ef based on the detection result of the interference light by the detector 155. This OCT image is a narrow-angle image. A ghost is not drawn at the center of the narrow-angle image (or the ghost is hardly noticeable).

(S15)
Subsequently, the alignment unit 220A has a region (corresponding region) corresponding to the OCT image (narrow-angle image) of the eye E acquired in S14 in the OCT image (wide-angle image) of the eye E acquired in S12. Is identified. As described above, the alignment unit 220A performs alignment between the OCT image (wide-angle image) of the eye E acquired in S12 and the OCT image (narrow-angle image) of the eye E acquired in S14. .

  The scale adjustment unit 220B determines whether the wide-angle image and the narrow-angle image that have been aligned by the alignment unit 220A based on the angle of view set in the wide-angle shooting mode and the angle of view set in the high-magnification shooting mode. Match the scales. At this time, the scale adjustment unit 220B (data processing unit 220) can perform known distortion correction processing and color correction processing on at least one of the wide-angle image and the narrow-angle image. The image composition unit 220C composes a wide-angle image and a narrow-angle image that have been scale-adjusted by the scale adjustment unit 220B, thereby forming a composite image in which the ghost at the center is removed (or suppressed). For example, the image composition unit 220C forms a composite image by replacing the central region of the wide-angle image with at least a partial region of the narrow-angle image corresponding to the central region.

(S16)
The display control unit 201C causes the UI unit 230 to display the composite image formed in S15.

(S17)
Similarly to S7, the control unit 200 determines whether or not the user can diagnose the eye E based on the composite image displayed in S16. When it is determined that the diagnosis is possible (S17: Y), the operation of the ophthalmologic photographing apparatus ends (end). When it is determined that the diagnosis is not possible (S17: N), the operation of the ophthalmologic photographing apparatus proceeds to S18.

(S18)
When it is determined that the diagnosis is not possible (S17: N), the display control unit 201C receives the user's predetermined operation on the UI unit 230, and the display control unit 201C acquires the OCT image (narrow angle image) of the eye E acquired in S14. Is enlarged and displayed on the UI unit 230. Thereafter, the operation of the ophthalmologic photographing apparatus ends (END).

  FIG. 5 illustrates a case where a wide-angle SLO image and a narrow-angle SLO image are combined, and FIG. 7 illustrates a case where a wide-angle OCT image and a narrow-angle OCT image are combined. You may make it synthesize | combine these, when the other is an OCT image.

“Third example of operation”

  FIG. 8 shows a third operation example of the ophthalmologic photographing apparatus according to the embodiment. FIG. 8 is a flowchart illustrating an operation example of the ophthalmologic photographing apparatus when a wide-angle SLO image and a narrow-angle SLO image are combined and only the narrow-angle SLO image is updated.

(S21)
First, similarly to S1, the objective optical unit 110B is inserted into the optical axis O by the angle-of-view changing mechanism 116. For example, a user such as an examiner, a subject, a doctor, or a patient manually inserts the objective optical unit 110B into the optical axis O.

  When the objective optical unit 110B is inserted into the optical axis O, the control unit 200 acquires an anterior segment image by capturing the anterior segment of the eye E with the anterior segment imaging system 120. The alignment control unit 201A controls the movement mechanism 100D based on the acquired anterior segment image, thereby aligning the optical system 100 and the objective optical system 110 with respect to the eye E (X direction, Y direction, and Z direction). direction). The control unit 200 moves the optical scanner 136 to a predetermined initial position. In S21, the tracking control unit 201B may start tracking control for the SLO image.

(S22)
The control unit 200 turns on the SLO light source 131 and controls the optical scanner 136 to start scanning the fundus oculi Ef of the eye E with the light from the SLO light source 131. The SLO image forming unit 210A forms an SLO image of the fundus oculi Ef based on the detection result of the fundus reflected light by the detector 135. The SLO image obtained in S22 is a wide-angle image.

(S23)
Next, the objective optical unit 110B is retracted from the optical axis O by the angle-of-view changing mechanism 116. For example, a user such as an examiner, a subject, a doctor, or a patient manually retracts the objective optical unit 110B from the optical axis O. When the objective optical unit 110B is retracted from the optical axis O, as in S1, the control unit 200 performs alignment and moves the optical scanner 136 to a predetermined initial position.

(S24)
As in S22, the control unit 200 controls the optical scanner 142 to start scanning the fundus oculi Ef of the eye E with the measurement light LS based on the light from the OCT light source 151. At this time, it is set so that the region including the central portion of the SLO image acquired in S22 is scanned. The SLO image forming unit 210A forms an SLO image of the fundus oculi Ef based on the detection result of the fundus reflected light by the detector 135. The SLO image obtained in S24 is a narrow-angle image.

(S25)
Subsequently, the alignment unit 220A, in the SLO image (wide angle image) of the eye E acquired in S22, a region (corresponding region) corresponding to the SLO image (narrow angle image) of the eye E acquired in S24. Is identified. As described above, the alignment unit 220A performs alignment between the SLO image (wide-angle image) of the eye E acquired in S22 and the SLO image (narrow-angle image) of the eye E acquired in S24. .

  The scale adjustment unit 220B determines whether the wide-angle image and the narrow-angle image that have been aligned by the alignment unit 220A based on the angle of view set in the wide-angle shooting mode and the angle of view set in the high-magnification shooting mode. Match the scales. At this time, the scale adjustment unit 220B (data processing unit 220) can perform known distortion correction processing and color correction processing on at least one of the wide-angle image and the narrow-angle image. The image composition unit 220C composes a wide-angle image and a narrow-angle image that have been scale-adjusted by the scale adjustment unit 220B, thereby forming a composite image in which the ghost at the center is removed (or suppressed). For example, the image composition unit 220C forms a composite image by replacing the central region of the wide-angle image with at least a partial region of the narrow-angle image corresponding to the central region.

(S26)
The display control unit 201C displays the composite image formed in S25 on the UI unit 230.

(S27)
Similarly to S7, the control unit 200 determines whether or not the user can diagnose the eye E based on the composite image displayed in S26. When it is determined that the diagnosis is possible (S27: Y), the operation of the ophthalmologic photographing apparatus proceeds to S24. Thereby, a new narrow-angle SLO image is acquired in S24, and in S25, the narrow-angle SLO image in the composite image is updated to the narrow-angle SLO image newly acquired in S24. In this case, every time a narrow-angle SLO image is acquired, the narrow-angle SLO image in the composite image is updated with a new narrow-angle SLO image.

  When it is determined in S27 that diagnosis is not possible (S27: N), the operation of the ophthalmologic photographing apparatus proceeds to S28.

(S28)
When it is determined that the diagnosis is not possible (S27: N), the display control unit 201C receives the user's predetermined operation on the UI unit 230, and the display control unit 201C acquires the SLO image (narrow angle image) of the eye E acquired in S24. Is enlarged and displayed on the UI unit 230. Thereafter, the operation of the ophthalmologic photographing apparatus ends (END).

  FIG. 8 illustrates a case where a wide-angle SLO image and a narrow-angle SLO image are synthesized and only the narrow-angle SLO image is updated. However, a wide-angle OCT image and a narrow-angle OCT image are synthesized. The same applies when only the narrow-angle OCT image is updated. Also, a wide-angle SLO image and a narrow-angle OCT image are synthesized, and only a wide-angle SLO image or a narrow-angle OCT image is updated, or a wide-angle OCT image and a narrow-angle SLO image are synthesized. Only the OCT image or the narrow-angle SLO image may be updated.

<Modification>
The configuration of the objective optical unit 110B according to the embodiment is not limited to that shown in FIGS.

(First modification)
FIG. 9A shows a configuration example of an objective optical unit 110B according to a first modification of the embodiment. In FIG. 9A, parts similar to those in FIG.

  The objective optical unit 110B according to the first modification includes one or more aberration correction lenses (aberration correction elements) in addition to the first spherical mirror 111B and the second spherical mirror 112B. At least one of the one or more aberration correction lenses may be disposed between the first spherical mirror 111B and the second spherical mirror 112B. For example, the objective optical unit 110B includes aberration correction lenses 113B and 114B in addition to the first spherical mirror 111B and the second spherical mirror 112B. The aberration correction lens 113B is disposed between the first spherical mirror 111B and the second spherical mirror 112B. The aberration correction lens 114B is disposed between the second spherical mirror 112B and the objective optical unit 110A (convex lens 111A).

  According to the first modified example, it is possible to perform aberration correction with high accuracy when performing wide-angle imaging with a simple configuration as compared with the embodiment.

(Second modification)
FIG. 9B shows a configuration example of the objective optical unit 110B according to the second modification of the embodiment. In FIG. 9B, the same parts as those in FIG.

  The objective optical unit 110B according to the second modified example includes an objective lens 115B disposed to face the eye E as an optical element of the catadioptric optical system. In the vicinity of the optical axis O on the first lens surface on the optical system 100 side of the objective lens 115B, a first light transmitting region 115a is provided. A first internal reflection region 115b is provided in at least a part of the region other than the first light transmission region 115a on the first lens surface of the objective lens 115B. A second light transmitting region 115c is provided in the vicinity of the optical axis O on the second lens surface on the eye E side of the objective lens 115B. A second internal reflection region 115d is provided in at least a part of the region other than the second light transmission region 115c on the second lens surface of the objective lens 115B.

  The first light transmitting region 115a and the second light transmitting region 115c are regions through which light passes. The first internal reflection region 115b and the second internal reflection region 115d are regions that reflect light guided through the objective lens 115B toward the inside of the objective lens 115B. For example, the first internal reflection region 115b is formed by performing a known coating process on a region other than the first light transmission region 115a on the first lens surface. Similarly, a second internal reflection region 115d is formed by performing a known coating process on a region other than the second light transmission region 115c on the second lens surface.

  The objective optical unit 110B passes light that has passed through the objective optical unit 110A, slanted with respect to the optical axis O, and passed through the first light transmission region 115a, into the second internal reflection region 115d and the first internal reflection region 115b. And then irradiates the fundus through the second light transmitting region 115c. The return light of the light irradiated on the fundus of the eye E is guided to the optical system 100 through the same path.

  According to the second modified example, the number of optical elements constituting the objective optical unit 110B can be significantly reduced as compared with the embodiment.

(Other variations)
In the embodiment, the case where the angle of view is changed by selectively arranging the objective optical unit corresponding to the photographing mode has been described, but the configuration according to the embodiment is not limited to this. For example, the optical system 100 may include a zoom optical system. In this case, the zoom optical system includes at least one objective optical system including two or more lenses that can move along the optical axis O of the optical system 100, or one or more optical elements that can be inserted into and removed from the optical axis O. (Lenses, prisms, plate glass, etc.). One or more optical elements can be inserted between the dichroic mirror DM2 and the objective optical unit.

  The control unit 200 according to the embodiment moves at least the objective optical system 110 (the optical system 100) so that the working distance (working distance) in the wide-angle photographing mode is shorter than the working distance in the high-magnification photographing mode. Also good.

  In the above-described embodiment, the case where the configuration of the optical system 100 is the configuration illustrated in FIGS. 1 and 3 has been described. However, the configuration of the optical system according to the embodiment is not limited to this. The optical system according to the embodiment may include an optical system for irradiating a treatment site on the fundus with laser light, an optical system for moving a visual target in a state of being fixed to the eye to be examined, and the like.

  In the above-described embodiment, the case where the configuration of the objective optical system 110 is the configuration illustrated in FIGS. 1 to 3 has been described. However, the configuration of the objective optical system according to the embodiment is not limited to this.

  The anterior ocular segment imaging system according to the embodiment may include two or more cameras for imaging the anterior segment of the eye E from two or more different directions. In this case, the alignment control unit 201A according to the embodiment executes alignment in the Z direction from the parallax obtained based on the captured images of the anterior segment from two or more different directions acquired using these cameras. It is possible.

  In the above-described embodiment, the case where alignment is performed using an anterior segment image acquired using the anterior segment imaging system 120 has been described. However, the acquired anterior segment image is displayed on the UI unit 230. It may be displayed on the device. Further, the acquired anterior ocular segment image need not be used for alignment.

[effect]
The effect of the ophthalmologic photographing apparatus according to the embodiment will be described.

  The ophthalmologic photographing apparatus according to the embodiment includes an objective optical system (objective optical system 110) and a scan system (optical system 100). The scan system is used to scan the fundus (fundus Ef) with a light beam via the objective optical system. The objective optical system includes an optical element including a first optical member (second spherical mirror 112B) and a second optical member (first spherical mirror 111B) disposed closer to the eye to be examined (eye E) than the first optical member. Including a unit (objective optical unit 110B), the second light beam is reflected at least twice by the light beam passing through the region near the optical axis in the first optical member while being inclined with respect to the optical axis (optical axis O) of the scan system. The fundus is irradiated through a region near the optical axis of the optical member.

  According to such a configuration, since the fundus is scanned by the scanning system using the first optical member and the second optical member, which are the optical members of the reflecting optical system, the objective optical system and the eye to be inspected are used. It is possible to acquire a wide-angle image in which ghost (noise) due to the surface reflection of the cornea is suppressed. Further, the number of optical elements constituting the objective optical system can be reduced, and the configuration can be simplified.

  In the ophthalmologic photographing apparatus according to the embodiment, the objective optical system may include one or more aberration correction elements (aberration correction lenses 113B and 114B).

  According to such a configuration, it is possible to perform highly accurate aberration correction with a simple configuration while greatly reducing the number of optical elements.

  In the ophthalmologic photographing apparatus according to the embodiment, at least one of the one or more aberration correction elements (aberration correction lens 113B) may be disposed between the first optical member and the second optical member.

  According to such a configuration, it becomes possible to perform highly accurate aberration correction with a simple configuration.

  In the ophthalmologic photographing apparatus according to the embodiment, each of the surface on the eye side of the first optical member and the surface on the scan system side of the second optical member may reflect the light beam.

  According to such a configuration, in the objective optical system disposed between the scan system and the eye to be examined, the light beam is emitted between the surface on the eye side of the first optical member and the surface on the scan system side of the second optical member. Since the light is reflected, the size of the objective optical system can be reduced. Thereby, the ophthalmologic photographing apparatus can be miniaturized.

  In the ophthalmologic photographing apparatus according to the embodiment, the vicinity region may be formed as an opening or a light transmitting part.

  According to such a configuration, it is possible to acquire an image in which ghost (noise) due to surface reflection of the objective lens and the cornea of the eye to be examined is suppressed with a simple configuration.

  The ophthalmologic photographing apparatus according to the embodiment includes an objective optical system (objective optical system 110) and a scan system (optical system 100). The scan system is used to scan the fundus (fundus Ef) with a light beam via the objective optical system. The objective optical system includes an optical unit (objective optical unit 110B) including an objective lens (objective lens 115B) disposed to face the eye to be examined (eye E), and the objective lens is a first lens on the scan system side. First internal reflection formed on at least a part of the first light transmission region formed in the vicinity of the optical axis (optical axis O) of the scan system on the surface and the first lens surface on the first lens surface. A second light-transmitting region formed in the vicinity of the optical axis on the second lens surface on the eye side to be examined, and a second region formed on at least a part of the second lens surface other than the second light-transmitting region. An internal reflection region, and reflects the light beam that has passed through the first light-transmitting region obliquely with respect to the optical axis to the fundus through the second light-transmitting region after being reflected by the first internal reflection region and the second internal reflection region. Irradiate.

  According to such a configuration, the objective optical system is an optical member of the catadioptric optical system, the first light transmission region and the first internal reflection region are formed on the first lens surface, and the second light transmission is formed on the second lens surface. Since the fundus is scanned by the scanning system using the objective lens in which the region and the second internal reflection region are formed, the ghost (noise) due to the surface reflection of the objective lens and the cornea of the eye to be examined is suppressed. A wide-angle image can be acquired. Further, the number of optical elements constituting the objective optical system can be reduced, and the configuration can be simplified.

  In the ophthalmologic photographing apparatus according to the embodiment, the objective optical system includes one or more lenses (convex lenses 111A and 112A and concave lens 113A) disposed between the scan system and the optical unit. It may be detachable with respect to the optical path.

  According to such a configuration, it is possible to provide an ophthalmologic photographing apparatus capable of acquiring a wide-angle image in which ghost rendering is suppressed while easily changing the angle of view by inserting and removing the optical unit in the objective optical system. it can.

  In addition, the ophthalmologic photographing apparatus according to the embodiment collects an image forming unit (image forming unit 210) that forms an image based on data collected by the scanning system, and the scanning system with an optical unit inserted in the optical path. A first image (wide-angle image) formed by the image forming unit based on the acquired data, and a second image formed by the image forming unit based on the data collected by the scan system with the optical unit retracted from the optical path An image composition unit (image composition unit 220C) that forms a composite image by combining the (narrow angle image).

  According to such a configuration, a ghost resulting from the surface reflection of the objective lens or the cornea of the eye to be examined is not depicted in the central portion, but the first image having a wide angle in which the fundus is not depicted in the central portion, and the ghost is depicted in the central portion. However, since the second image with a narrow angle in which the fundus with a high magnification is depicted in the central portion is synthesized, it is possible to acquire a wide angle image in which the ghost image is suppressed.

  In the ophthalmologic photographing apparatus according to the embodiment, the image composition unit may form a composite image in which the second image is arranged in the central part and the first image is arranged in the peripheral part.

  According to such a configuration, the second image with a narrow angle of the fundus is arranged in the center, and the composite image in which the first image with a wide angle of the fundus is arranged in the periphery is formed. It is possible to acquire a wide-angle image in which the image is suppressed.

  The embodiment described above is merely an example for carrying out the present invention. A person who intends to implement the present invention can make arbitrary modifications, omissions, additions and the like within the scope of the present invention.

DESCRIPTION OF SYMBOLS 100 Optical system 110 Objective optical system 110A, 110B Objective optical unit 111B 1st spherical mirror 112B 2nd spherical mirror 116 Angle-of-view changing mechanism 120 Anterior eye imaging system 130 SLO optical system 140 OCT optical system 150 Interference optical system 200 Control part 210 Image formation Unit 220 data processing unit 220C image composition unit 230 UI unit DM1 dichroic mirror E eye Ef eye fundus

Claims (9)

An objective optical system;
A scanning system for scanning the fundus with a light beam through the objective optical system;
Including
The objective optical system is
An optical unit including a first optical member, and a second optical member disposed closer to the subject's eye than the first optical member,
Reflecting at least twice the light beam that has been inclined with respect to the optical axis of the scan system and has passed through the region near the optical axis in the first optical member, and passes through the region near the optical axis in the second optical member. An ophthalmologic photographing apparatus irradiating the fundus. The ophthalmologic photographing apparatus according to claim 1, wherein the objective optical system includes one or more aberration correction elements. The ophthalmologic photographing apparatus according to claim 2, wherein at least one of the one or more aberration correction elements is disposed between the first optical member and the second optical member. 4. Each of the surface on the eye side of the first optical member and the surface on the scan system side of the second optical member reflects the light flux. 5. The ophthalmologic photographing apparatus described in 1. The ophthalmologic photographing apparatus according to any one of claims 1 to 4, wherein the vicinity region is formed as an opening or a light transmitting portion. An objective optical system;
A scanning system for scanning the fundus with a light beam through the objective optical system;
Including
The objective optical system includes an optical unit including an objective lens disposed to face the eye to be examined.
The objective lens is
A first light transmissive region formed in the vicinity of the optical axis of the scan system on the first lens surface on the scan system side;
A first internal reflection region formed in at least a part of a region other than the first light transmission region on the first lens surface;
A second light-transmitting region formed in the vicinity of the optical axis in the second lens surface on the eye side to be examined;
A second internal reflection region formed in at least a part of the region other than the second light transmission region on the second lens surface;
With
The light beam that has passed through the first light-transmitting region obliquely with respect to the optical axis is reflected by the first internal reflection region and the second internal reflection region and irradiated to the fundus through the second light-transmitting region. An ophthalmologic photographing apparatus characterized by: The objective optical system includes one or more lenses disposed between the scan system and the optical unit,
The ophthalmologic photographing apparatus according to any one of claims 1 to 6, wherein the optical unit can be inserted into and removed from an optical path of the light beam. An image forming unit that forms an image based on data collected by the scan system;
A first image formed by the image forming unit based on data collected by the scan system in a state where the optical unit is inserted in the optical path; and the scan system in a state where the optical unit is retracted from the optical path. An image combining unit that combines the second image formed by the image forming unit based on the data collected by the image forming unit to form a combined image;
The ophthalmologic photographing apparatus according to claim 7, comprising: The ophthalmologic photographing apparatus according to claim 8, wherein the image composition unit forms the composite image in which the second image is disposed in a central portion and the first image is disposed in a peripheral portion.

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