JP6775302B2 - Ophthalmologic imaging equipment - Google Patents

Description

The present invention relates to an ophthalmologic imaging apparatus.

There is a demand for an ophthalmologic imaging device for screening for eye diseases and the like, which can easily image the fundus of the eye to be examined in a wide field of view. As such an ophthalmologic imaging apparatus, a scanning laser optical probe (hereinafter referred to as SLO) is known. The SLO is a device 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 can perform scanning in a wide area and scanning that enlarges a part of the scanning area by controlling them.

JP-A-2015-229023

However, it is known that ghosts (noise) caused by surface reflection of the objective lens and the cornea of the eye to be inspected are drawn in the central portion of the image acquired by an ophthalmologic imaging device such as SLO. The size and amount of light of the ghost increase as the angle of view increases. In many cases, a region of interest is placed in the center of the acquired image, and if a ghost is drawn in the center, the diagnosis may be hindered. It is desirable to suppress such ghosts not only for those drawn in the center but also for those drawn at arbitrary positions in the image.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an ophthalmologic imaging apparatus capable of suppressing the depiction of ghosts even in an image having a wide angle of view.

Ophthalmic imaging apparatus according to the embodiment includes an optical system for photographing a fundus of an eye to be examined, and a changing unit that relatively changing the direction of the optical axis direction and the optical system of the eye, the subject's eye and the optical axis Is set to the second relative orientation, which is different from the first relative orientation, in the partial region of the first image obtained by using the optical system and the noise is drawn when is set to the first relative orientation. includes, an image combining unit for generating a composite image was replaced with the corresponding zones within the area of the second in the image obtained using the optical system when the image combining unit, first obtained by the optical system 1 The subregion is specified based on the pixel value of the image.
Further, the ophthalmologic imaging apparatus according to the embodiment includes an optical system for photographing the fundus of the eye to be inspected, a changing portion for relatively changing the direction of the eye to be inspected and the direction of the optical axis of the optical system, and the eye to be inspected and light. The partial region of the first image acquired by using the optical system and depicting the noise when the axis is set to the first relative orientation is set to the second relative orientation different from the first relative orientation. The image compositing unit includes an image compositing unit that generates a composite image replaced with a region corresponding to a partial region in the second image acquired by using the optical system while the image compositing unit is in the first relative orientation. The subregion is determined based on the difference from the second relative orientation.

According to the present invention, it is possible to provide an ophthalmologic imaging apparatus capable of suppressing the depiction of ghosts even in an image having a wide angle of view.

It is a functional block diagram which shows the schematic structure of the ophthalmologic imaging apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the optical system of the ophthalmologic imaging apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the optical system of the ophthalmologic imaging apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the optical system of the ophthalmologic imaging apparatus which concerns on embodiment. It is the schematic which shows an example of the structure of the processing system of the ophthalmologic imaging apparatus which concerns on embodiment. It is operation explanatory drawing of the ophthalmologic imaging apparatus which concerns on embodiment. It is operation explanatory drawing of the ophthalmologic imaging apparatus which concerns on embodiment. It is a flow chart of the operation example of the ophthalmologic imaging apparatus which concerns on embodiment. It is a functional block diagram which shows the schematic structure of the ophthalmologic imaging apparatus which concerns on the modification of embodiment.

An example of an embodiment of the ophthalmologic imaging apparatus according to the present invention will be described in detail with reference to the drawings. In addition, the description contents of the document cited in this specification and any known technique can be incorporated into the following embodiments.

The ophthalmologic imaging apparatus according to the embodiment moves an optical unit including a scanning optical system that deflects light from a light source with reference to the pupil of the eye to be inspected, thereby transmitting light through the pupil to the posterior eye portion (fundus, glass) of the eye to be inspected. It is a device that can irradiate a wide range of the body, etc.). Such a configuration can be applied to any ophthalmologic imaging apparatus capable of irradiating the posterior segment of light with light. Ophthalmologic imaging devices that can irradiate the back of the eye are laser treatment devices for irradiating the treatment site on the fundus with laser light, and patients who are subject to moving the optotype while staring at the eye to be inspected. It may be a perimeter or the like for measuring the visual field based on the response of the examiner (patient). Further, the ophthalmologic imaging device according to the embodiment may be a fundus observation device (fundus camera) that does not have a scanning optical system.

Further, the ophthalmologic imaging apparatus according to the embodiment forms a distribution of predetermined data (image, layer thickness distribution, lesion distribution, etc.) in the posterior eye portion by receiving the return light from the posterior segment of the eye to be inspected. Is possible. Such a configuration can be applied to any ophthalmologic imaging apparatus capable of acquiring data by scanning the posterior segment of the eye with light. Ophthalmologic imaging devices that can acquire data by scanning the back of the eye with light include SLO, which obtains a frontal image of the fundus by laser scanning using a confocal optical system, and Optical Coherence Tomography (hereinafter referred to as “Optical Coherence Tomography”). There is an optical coherence tomography that obtains a tomographic image of the fundus using OCT). Hereinafter, the ophthalmologic imaging apparatus according to the embodiment will be described as a multifunction device that combines the functions of the SLO and the functions of the optical interference tomography.

Hereinafter, the left-right direction as viewed from the subject is the X direction, the vertical direction is the Y direction, and the depth direction of the optical system as viewed from the subject is the Z direction.

[Constitution]
FIG. 1 shows a functional block diagram of a schematic configuration of an ophthalmologic imaging apparatus according to an embodiment.

The ophthalmologic imaging apparatus 1 is an apparatus that scans the posterior segment of the eye to be inspected E with a laser beam to acquire data, and forms a frontal image of the fundus Ef based on the acquired data. The ophthalmologic imaging apparatus 1 includes a measurement unit 10 and a processing unit 70. The measuring unit 10 is used for optically observing the fundus Ef and optically measuring the fundus Ef. The processing unit 70 processes the data acquired by the measuring unit 10 and controls each part of the apparatus.

(Measurement unit)
The measuring unit 10 includes an optical unit 20, a moving mechanism 30, a driving unit 30D, a light source 40, an optometry optical system 50, and an alignment system 60. The measurement unit 10 transmits light from the light source 40 through the pupil of the eye E to be inspected by an optical unit 20 configured to be movable based on the pupil position (pupil position) R (or a position in the vicinity of the pupil position R) of the eye E to be inspected. Irradiate the posterior segment of the eye E to be inspected. The pupil position R of the eye to be inspected E or a position in the vicinity thereof is a position separated from the objective lens included in the optical unit 20 by a predetermined distance along the optical axis of the optical unit 20. The predetermined distance corresponds to the working distance of the optical unit 20 plus the interpupillary distance between the corneal pupils of the eye E to be inspected. The measurement unit 10 sends the data acquired by receiving the return light of the light applied to the rear eye portion of the eye E to be inspected to the processing unit 70.

The optical unit 20 includes a scanning optical system 21, a projection system 22, and a light receiving system 23.

The scanning optical system 21 deflects the light from the light source 40 within a predetermined deflection angle range. In the embodiment, the scanning optical system 21 two-dimensionally deflects the light from the light source 40 within a predetermined deflection angle range, but one-dimensionally deflects the light from the light source 40 within a predetermined deflection angle range. It may be configured as follows. Such a scanning optical system 21 may include an optical scanner. A uniaxial or biaxial deflecting member orthogonal to each other is used in the optical scanner. Examples of the deflecting member include a galvano mirror, a resonant mirror, a polygon mirror, a rotating mirror, a dove prism, a double dove prism, a rotation prism, a MEMS (Micro Electro Electro Mechanism System), and the like. There is.

The projection system 22 is an optical system including an optical element for projecting light from the light source 40 deflected by the scanning optical system 21 onto the rear eye portion (for example, fundus Ef) of the eye E to be inspected. The projection system 22 may include a scanning optical system 21.

The light receiving system 23 is an optical system including an optical element and a light receiving element for receiving the return light from the rear eye portion of the eye to be inspected E with respect to the light projected by the projection system 22. As the light receiving element, one having sensitivity in the visible region and the infrared region is used according to the light output from the light source 40. The light receiving system 23 may include a scanning optical system 21.

The optical unit 20 may include at least one of the light source 40 and the optometry optical system 50. At least one of the projection system 22 and the light receiving system 23 may be provided outside the optical unit 20.

The moving mechanism 30 can move the optical unit 20 in the X direction, the Y direction, and the Z direction. As a result, the eye E to be inspected and the optical unit 20 can be aligned with each other.

Further, the moving mechanism 30 moves the optical unit 20 within a predetermined moving angle range with reference to the pupil position R of the eye E to be inspected. When the optical axis of the optical unit 20 passes through the pupil position R from the front side of the eye E to be inspected, the plane orthogonal to the optical axis is defined as the XY plane (the X direction is the horizontal direction and the Y direction is the vertical direction). Assuming that the direction of the fundus parallel to is the Z direction, the pupil position R includes not only the position actually corresponding to the pupil but also the X direction, the Y direction and / or from the pupil position R within a range that does not interfere with the scanning of the posterior segment of the eye. The position displaced in the Z direction (near position) is also included. Hereinafter, in this specification, when the term "pupil position" is simply expressed except when the "near position" is specified, it means the pupil position or its vicinity position.

The moving mechanism 30 rotates the optical unit 20 within a predetermined movement angle range around the pupil position R of the eye E to be inspected. Such a moving mechanism 30 is configured to include, for example, one or more holding members for holding the optical unit 20 and one or more guide arms movably provided at an arbitrary position in the moving angle range. Ru. The guide arm holds the holding member in a slidable state. Thereby, the orientation of the eye E to be inspected (the orientation of the eyeball) and the orientation of the optical axis of the optical unit 20 can be relatively changed. That is, light can be projected onto the rear eye portion of the eye E to be inspected from different directions, and the return light can be received.

The drive unit 30D receives control from the control unit 200 of the processing unit 70, which will be described later, and drives the moving mechanism 30. The drive unit 30D includes an actuator that generates a driving force for moving the moving mechanism 30. The actuator that receives the control signal from the control unit 200, which will be described later, generates a driving force corresponding to the control signal. This driving force is transmitted to the moving mechanism 30 via a driving force transmission mechanism (not shown), and moves the moving mechanism 30 so as to be arranged at a position designated by a control signal. This makes it possible to move the optical unit 20 to a desired position.

The light source 40 outputs light (for example, laser light) for irradiating the rear eye portion of the eye E to be inspected. The light source 40 includes a semiconductor laser light source (wavelength sweep laser, superluminescent diode, etc.), a solid-state laser, a gas laser, a fiber laser, and the like. It is also possible to apply a light source 40 in which a plurality of light sources are combined and used by a combiner such as an optical fiber combiner or a dichroic mirror. In this embodiment, the laser beam is guided to the optical unit 20 by an optical fiber. For example, the joint portion of the optical fiber is provided with means for reducing stress such as twisting and pulling caused by the movement of the optical unit 20.

The optometry optical system 50 includes a configuration for realizing at least one of internal optometry and external optometry. When realizing internal fixation, the fixation optical system 50 includes an optical system for projecting an fixation target onto the fundus Ef of the eye E to be inspected. The fixation target is a target for fixing the eye E to be inspected. The optometry optical system 50 includes at least a optometry light source that outputs visible light. For example, the optical path formed by the optometry optical system 50 is coupled to the optical path formed by the projection system 22 or the light receiving system 23 in the optical unit 20. Thereby, the fixation optical system 50 can present the fixation target to the eye E to be inspected through the optical path formed by the optical unit 20. The optometry optical system 50 may be included in the optical unit 20.

When realizing external fixation, the fixation optical system 50 is provided, for example, in the housing of the optical unit 20. The optometry optical system 50 has, for example, a configuration in which one end is fixed to the optical unit 20 and a light emitting portion such as an LED is provided at the other end of two or more arms connected to each other via a joint portion. When realizing external optometry, the optometry optical system 50 may be provided in the housing of the measurement unit 10 and may be configured not to move together with the optical unit 20.

When the optometry optical system 50 realizes internal optometry, the control unit 200 can move the projection position (presentation position) of the optometry target with the movement of the optical unit 20. When the optometry optical system 50 realizes both internal optometry and external optometry, the control unit 200 can link the internal optometry and the external optometry by using the above configuration. As an example of linking internal fixation and external fixation, when the macula is included in the scan area of light, the eye to be inspected is fixed by internal fixation, and the macula is not included in the scan area. Occasionally, external fixation causes the eye to be fixed.

Further, the optometry optical system 50 may include a configuration (optical system) for realizing two or more internal optometry. When realizing two internal optometry, the optometry optical system 50 is provided inside the optical unit 20 to realize the first internal optometry, and the second internal is provided outside the optical unit 20. It may include a configuration for achieving optometry. As an example of linking two internal fixations, when a yellow spot is included in the scan area of light, the first internal fixation (inside the optical unit 20) causes the eye E to be fixed, and the inside of the scan area is fixed. When the yellow spot portion is not included in the eye, the eye E to be inspected is fixed by the second internal fixation (outside of the optical unit 20).

The alignment system 60 includes, for example, an XY alignment detection light source, an XY alignment sensor, a Z alignment detection light source, and a Z alignment sensor. The light for XY alignment detection from the XY alignment light source is guided as a parallel light flux to the cornea of the eye E to be inspected. A bright spot image (virtual image) is formed on the cornea by the corneal reflection of the light for XY alignment detection. The XY alignment detection light reflected by the cornea is detected by the XY alignment sensor. The detection signal obtained by the XY alignment sensor is sent to the control unit 200. The control unit 200 identifies the position of the bright spot image formed on the cornea of the eye E to be inspected from this detection signal, and detects the positional deviation with respect to the optical unit 20 in the X direction and the Y direction.

The light for Z alignment detection from the light source for Z alignment detection is projected onto the cornea of the eye E to be inspected. A bright spot image (virtual image) is formed on the cornea by the corneal reflection of the light for Z alignment detection. The light for Z alignment detection reflected by the cornea is detected by the Z alignment sensor. The detection signal obtained by the Z alignment sensor is sent to the control unit 200. The control unit 200 identifies the position of the bright spot image formed on the cornea of the eye E to be inspected from this detection signal, and detects the positional deviation with respect to the optical unit 20 in the Z direction.

Further, at least one of the above XY alignment and Z alignment may be performed using one or more cameras provided in the measurement unit 10. In this case, by determining the position of the eye E to be inspected based on the images taken by one or more cameras, at least one misalignment in the X direction, the Y direction, and the Z direction is detected. When two or more cameras are provided, the three-dimensional position of the eye E to be inspected is obtained based on images taken substantially simultaneously from different directions in the X direction, the Y direction, and the Z direction. At least one misalignment is detected.

The control unit 200 performs alignment by moving the optical unit 20 by the moving mechanism 30 so as to cancel the detected misalignment in the X, Y, and Z directions.

The measurement unit 10 may include a focus optical system and generate an index (split index) for focusing (focusing) on the fundus Ef. In this case, the light output from the focus optical system (focus light) is projected onto the fundus Ef. The fundus reflected light of the light projected on the fundus Ef is detected by a sensor (not shown). The control unit 200 can analyze the position of the split index from the detection signal obtained by this sensor, and for example, move the focusing lens and the focus optical system included in the optical unit 20 to perform focusing (focusing). Autofocus function).

[Optical system]
Next, it is assumed that the ophthalmologic imaging apparatus 1 according to the embodiment has the function of SLO and the function of an optical interference tomographic meter, and a configuration example of the optical unit 20 of FIG. 1 will be described. In the following, the illustration of the optometry optical system 50 is omitted. Further, it is assumed that the function of the alignment system 60 of FIG. 1 is realized by the anterior segment imaging system 120 or the like.

The ophthalmologic imaging apparatus 1 can acquire an image of the eye E to be inspected in a range corresponding to the imaging mode. The ophthalmologic imaging apparatus 1 can selectively arrange the objective lens unit corresponding to the imaging mode on the optical axis of the optical system.

2 to 4 show a configuration example of the optical system included in the optical unit 20. The optical unit 20 includes an optical system 100. FIG. 2 shows a configuration example of the optical system 100 when the wide-angle (wide-angle) shooting mode is set. FIG. 3 shows a configuration example of an objective lens system according to an embodiment that can be switched according to a shooting mode. In FIG. 3, the same parts as those in FIG. 2 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. FIG. 4 shows a configuration example of the optical system 100 when the high-magnification shooting mode is set. In FIG. 4, the same parts as those in FIGS. 2 or 3 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. In FIGS. 2 and 4, the position optically coupled to the fundus Ef of the eye E to be inspected is illustrated as the fundus conjugate position P, and the position optically conjugated to the pupil of the eye E to be inspected is illustrated as the pupil conjugate position Q. There is.

The optical system 100 includes a projection system that projects light onto the eye to be inspected via the objective lens system 110, and a light receiving system that receives the return light of the light projected on the eye E to be inspected through the objective lens system 110. The ophthalmologic photographing apparatus 1 forms an image based on the light receiving result by the light receiving system. The ophthalmologic imaging apparatus 1 is capable of forming SLO images and OCT images. 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 SLO projection system and the OCT projection system realize the functions of the projection system 22 of FIG. The SLO light receiving system and the OCT light receiving system realize the function of the light receiving system 23 of FIG.

The optical system 100 is provided with an anterior segment imaging system (anterior segment observation system) 120 for photographing the anterior segment of the eye to be inspected. The optical system 100 can be moved in the X direction, the Y direction, and the Z direction by the moving mechanism 30 together with the objective lens system 110 and the anterior segment imaging system 120. The ophthalmologic imaging apparatus 1 moves the optical system 100 or the like by a moving mechanism based on the anterior segment image of the eye to be inspected E obtained by the anterior ocular segment imaging system 120, so that the optical system 100 is moved with respect to the eye to be inspected E. It is possible to perform alignment for alignment. Hereinafter, the case where the optical system 100 includes the objective lens system 110 and the anterior segment imaging system 120 will be described, but the optical system 100 may not include these.

(Objective lens system)
The ophthalmologic imaging apparatus 1 can arrange the objective lens unit according to the imaging mode on the optical axis O of the optical system 100. In this embodiment, the shooting modes include a wide-angle shooting mode in which the image of the eye E to be examined is taken in the first range (for example, the angle of view is 100 degrees) and a second range (for example, the angle of view is 50 degrees) narrower than the first range. There is a high-magnification shooting mode in which the image of the eye E to be inspected is taken with).

The objective lens system 110 includes objective lens units 110A and 110B (see FIG. 3). For example, the objective lens units 110A and 110B can be manually and selectively arranged on the optical axis O by a known rotation mechanism or slide mechanism. In the wide-angle shooting mode, the optical axis of the objective lens unit 110A is arranged so as to coincide with the optical axis of the optical system 100 (FIG. 2). In the high-magnification shooting mode, the optical axis O is arranged so that the optical axis of the objective lens unit 110B coincides with the optical axis O (FIG. 4).

The objective lens unit 110A includes two or more lenses. A dichroic mirror DM1A is provided between the two or more lenses. For example, the objective lens unit 110A may be a lens unit (nuggler type) including convex lenses 111A and 112A and a concave lens 113A. The convex lenses 111A, 112A, and the concave lens 113A are arranged in this order from the side of the eye E to be inspected. A dichroic mirror DM1A is arranged between the convex lens 112A and the concave lens 113A. The dichroic mirror DM1A is an optical path coupling member that connects the optical path of the anterior 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 in the wide-angle imaging mode. A position (fundus conjugate position) P optically conjugate with the fundus (retina) or a vicinity thereof is arranged between the dichroic mirror DM1A and the concave lens 113A. The objective lens unit 110A may include a dichroic mirror DM1A.

The dichroic mirror DM1A emits light from the SLO optical system 130 (SLO light), return light from the eye E to be inspected, light from the OCT optical system 140 (OCT light, measurement light), and return light from the eye E to be inspected. Make it transparent. The dichroic mirror DM1A reflects the light from the anterior segment imaging system 120 toward the eye to be inspected E, and reflects the return light from the eye to be inspected E toward the anterior segment imaging system 120.

The objective lens unit 110B includes at least one lens. A dichroic mirror DM1B is provided on the light source (SLO light source and OCT light source) side for the at least one lens. For example, the objective lens unit 110B may include a convex lens 111B. The dichroic mirror DM1B is an optical path coupling member that connects the optical path of the anterior 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 in the high-magnification imaging mode. The objective lens unit 110B may include a dichroic mirror DM1B.

Like the dichroic mirror DM1A, the dichroic mirror DM1B includes light from the SLO optical system 130 (SLO light), return light from the eye E to be inspected, light from the OCT optical system 140 (OCT light, measurement light) and its covering. The return light from the eye examination E is transmitted. Further, the dichroic mirror DM1B reflects the light from the anterior segment imaging system 120 toward the eye to be inspected E, and reflects the return light from the eye to be inspected E toward the anterior segment imaging system 120. The position of the dichroic mirror DM1B on the optical axis O when the objective lens unit 110B is arranged on the optical axis O is the dichroic mirror DM1A on the optical axis O when the objective lens unit 110A is arranged on the optical axis O. It may be substantially the same as the position of. As a result, when the photographing mode is changed, it is not necessary to adjust the position and orientation of the anterior segment imaging system 120.

The objective lens unit 110A may include only the convex lenses 111A and 112A and the concave lens 113A, and the objective lens unit 110B may include only the convex lens 111B. As a result, the dichroic mirrors DM1A and DM1B can be shared by one dichroic mirror when the objective lens unit arranged on the optical axis O is switched.

The objective lens system 110 can be moved along the optical axis O by a moving mechanism (moving mechanism 110D described later) (not shown). As a result, the objective lens system 110 can be moved in the Z direction with respect to the optical system 100, and the focal positions of both the SLO optical system 130 and the OCT optical system 140 can be changed.

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

(Anterior segment photography system)
The anterior segment imaging system 120 includes an anterior segment illumination light source 121, a collimating 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 connects the optical path of the return light to the optical path of the illumination light for illuminating the anterior segment of the eye E to be inspected. For example, the light source 40 shown in FIG. 1 may include an anterior segment illumination light source 121.

The anterior segment illumination light source 121 is a light source for illuminating the anterior segment of the eye E to be inspected. The anterior segment photographing camera 123 includes an imaging element for detecting reflected light (return light) from the anterior segment of the eye to be inspected 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 by the anterior segment illumination light source 121 is converted into a parallel luminous flux by the collimating lens 122. The illumination light as a parallel luminous flux is reflected by the beam splitter BS1 toward the dichroic mirror DM1A. The illumination light reflected by the beam splitter BS1 is deflected toward the eye E to be inspected by the dichroic mirror DM1A. The return light of the illumination light from the eye E to be inspected is reflected by the dichroic mirror DM1A and passes through the beam splitter BS1. The return light transmitted through the beam splitter BS1 is focused by the imaging lens 124 on the detection surface of the image sensor in the anterior segment imaging camera 123. The detection surface of the image sensor is arranged at or near the pupil conjugate position (anterior segment conjugate position) Q. The image sensor is composed of, for example, a CCD or CMOS image sensor. The detection result of the return light from the anterior segment of the eye E to be inspected by the image sensor is used for forming an image of the anterior segment.

(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 the 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 combines an optical path formed by the telecentric optical system of the SLO optical system 130 with an optical path formed by the telecentric optical system of the OCT optical system 140. As a result, even when the focal position of the optical system 100 is changed by moving the objective lens system 110, the aberration of the pupil (for example, the exit pupil by the objective lens system 110) is reduced, so that the focusing state can be easily adjusted.

It is desirable that the dichroic mirrors DM1A (DM1B) and DM2 are arranged on the optical axis O while maintaining a twisting relationship. The dichroic mirror DM1A (DM1B) includes at least a part of the light guided through the optical path of the SLO optical system 130 and the optical path of the OCT optical system 140 (the optical path of the optical system 100) and the light guided through the optical path of the anterior segment imaging system 120. It includes a first optical surface that reflects at least one of the lights and transmits the other. The dichroic mirror DM2 reflects at least a part of the light guided through the optical path of the SLO optical system 130 and at least a part of the light guided through the optical path of the OCT optical system 140, and transmits the other light. It is provided with a second optical surface to be used. The dicroic mirrors DM1A (DM1B) and DM2 are a plane including the normal of the first optical surface and the optical axis of the SLO optical system 130, and a plane including the normal of the second optical surface and the optical axis of the SLO optical system 130. Are arranged so as to be orthogonal to each other or substantially orthogonal to each other. As a result, in the high-magnification shooting mode shown in FIG. 4, since the concave lens 113A is not arranged between the dichroic mirror DM1B and the dichroic mirror DM2, the astigmatism is removed or the astigmatism is removed by the dichroic mirror DM1B and the dichroic mirror DM2. Can be made extremely small, so that deterioration of image quality can be suppressed. On the other hand, in the wide-angle shooting mode shown in FIG. 2, since the roughness of the image is allowed as compared with the high-magnification shooting mode, the influence on the image quality due to the residual astigmatism can be small.

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 diaphragm 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 on the eye E to be inspected.

As the SLO light source 131, for example, one that emits light having a center wavelength of 840 nm is used. Examples of the SLO light source 131 include a laser diode (hereinafter, LD), a super luminescent diode (SLD), and a laser driven light source (LDLS). The SLO light source 131 is arranged at or near the position (fundus conjugate position) P optically conjugate with the fundus (retina). For example, the light source 40 shown in FIG. 1 may include an SLO light source 131.

The light emitted from the SLO light source 131 is converted into a parallel luminous flux by the collimating lens 132. The light as a parallel luminous 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 to scan the fundus Ef of the eye E to be inspected 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 capable of deflecting light by changing the inclination of the reflecting surface, and the inclination of the reflecting surface is controlled by a control unit 200 described later. The optical scanner 136X is used, for example, for horizontal scanning within the fundus. An optical scanner 136Y is arranged on the side of the eye E to be inspected of the optical scanner 136X. The optical scanner 136Y is a mirror capable of deflecting light by changing the inclination of the reflecting surface, and the inclination of the reflecting surface is controlled by the control unit 200. The optical scanner 136Y is used, for example, for vertical scanning in the fundus that is orthogonal to the horizontal direction. Either one of the optical scanner 136X and the optical scanner 136Y may be a low-speed scanner such as a galvano mirror, and the other may be a high-speed scanner such as a resonant mirror, a polygon mirror, or a MEMS (Micro Electrical Mechanical Systems) mirror. The reflective surface of the optical scanner 136Y is arranged at or near the position (pupil conjugate position) Q that is optically conjugate with the pupil of the eye E to be inspected. A lens 137 and a dichroic mirror DM2 are arranged on the side of the eye E to be inspected 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 to be inspected via the objective lens system 110. The optical scanner 136 realizes the function of the scanning optical system 21 of FIG.

The return light of the light from the SLO light source 131 projected on the eye E to be inspected is reflected by the beam splitter BS2 toward the detector 135 via the same optical path. A confocal lens 133 and a confocal diaphragm 134 are arranged between the beam splitter BS2 and the detector 135. The condensing lens 133 condenses the light reflected by the beam splitter BS2. The light collected by the condenser lens 133 passes through the opening formed in the confocal aperture 134 and is incident on the detection surface of the detector 135. The opening formed in the confocal diaphragm 134 is arranged at or near the position (fundus conjugate position) P 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 (moving mechanism 141D described later) (not shown). As a result, the focal position of the OCT optical system 140 can be changed independently of the SLO optical system 130. Therefore, for example, after the focusing state of the SLO optical system 130 and the OCT optical system 140 is adjusted by moving the objective lens system 110, the focusing state of the OCT optical system 140 is finely adjusted by moving the focusing lens 141. Can be done.

The optical scanner 142 is used to scan the fundus Ef of the eye E to be inspected with the 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 capable of deflecting light by changing the inclination of the reflecting surface, and the inclination of the reflecting surface is controlled by the control unit 200. The optical scanner 142 is used, for example, for horizontal scanning within the fundus. An optical scanner 142Y is arranged on the side of the eye E to be inspected of the optical scanner 142X. The optical scanner 142Y is a mirror capable of deflecting light by changing the inclination of the reflecting surface, and the inclination of the reflecting surface is controlled by the control unit 200. The optical scanner 142Y is used, for example, for vertical scanning in the fundus that is 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 galvano mirror, and the other may be a high-speed scanner such as a high-speed galvano mirror. The intermediate positions of the optical scanners 142X and 142Y are arranged at or near the position (pupil conjugate position) Q that is optically conjugate with the pupil of the eye E to be inspected. A collimating lens 143 is arranged on the side of the OCT light source 151 of the optical scanner 142Y. The optical scanner 142 realizes the function of the scanning optical system 21 of FIG.

The interference optical system 150 is provided with an optical system for acquiring an OCT image of the eye E to be inspected. This optical system has the same configuration as a conventional Swept source type OCT device. 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 separates the return light of the measurement light from the eye E to be examined and the reference light via the reference optical path. It is an interference optical system that causes interference to generate interference light and detects this interference light. The detection result (detection signal) of the interference light by the interference optical system is a signal showing the spectrum of the interference light. The interference optical system 150 may have the same configuration as the conventional spectral domain type OCT device, instead of the Swept source type OCT device.

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 changes the output wavelength with time in a near-infrared wavelength band that is invisible to the human eye. For example, the light source 40 shown in FIG. 1 may include an OCT light source 151.

The light L0 output from the OCT light source 151 is guided by the optical fiber f1 to the fiber coupler 152 and 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 collimating lens 156 from the fiber exit end c1. The reference light LR emitted from the fiber exit end c1 is converted into a parallel luminous flux by the collimating lens 156. The reference light LR, which is a parallel luminous flux, is guided to the prism 154. The prism 154 turns back the traveling direction of the reference light LR, which is made into a parallel luminous flux by the collimated lens 156, in the opposite 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 can be moved in the direction along the incident optical path and the outgoing optical path of the reference light LR by a moving mechanism (moving mechanism 154D described later) (not shown). In this case, an actuator for generating a driving force for moving the moving mechanism and a transmission mechanism for transmitting the driving force are provided. The actuator is composed of, for example, a pulse motor. The transmission mechanism is composed of, for example, a combination of gears or a rack and pinion. As a result, 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 flux to a focused light flux by the collimated lens 157, is incident on the fiber incident end c2, and is guided to the fiber coupler 153 by the optical fiber f3. An optical path length correction member or a dispersion compensation member may be arranged between the collimating lenses 156 and 157 and the prism 154. The optical path length correction member acts as a delay means 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 compensating member acts as a dispersion compensating means for matching the dispersion characteristics between the reference light LR and the measurement light LS.

On the other hand, the measurement optical 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 collimating lens 143. The measurement light LS emitted from the fiber end c3 is converted into a parallel luminous flux by the collimating lens 143. The measurement light LS converted into a parallel luminous flux 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 lens system 110, and irradiated to the eye E to be inspected. The measurement light LS is scattered (including reflection) at various depth positions of the eye E to be inspected. The return light of the measurement light LS including such backscattered light travels in the same path as the outward path in the opposite direction, is guided to the fiber coupler 152, and reaches the fiber coupler 153 via the optical fiber f5.

The fiber coupler 153 combines (interferes with) the measurement light LS incidented through the optical fiber f5 and the reference light LR incidented via the optical fiber f3 to generate interference light. The fiber coupler 153 generates a pair of interference light LCs 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 light LCs emitted from the fiber coupler 153 are guided to the detector 155.

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

When the measurement unit 10 having the above configuration acquires the SLO image, the laser light output from the SLO light source 131 (light source 40) is two-dimensionally deflected by the optical unit 20 moved by the moving mechanism 30. To. The two-dimensionally polarized laser light is projected from the optical axis direction of the optical unit 20 to the fundus Ef through the pupil of the eye E to be inspected.

The return light of the laser beam projected on the fundus Ef is the light that returns to the optical unit 20 from the spot light formation position (and its vicinity position). The return light includes scattered light (reflected light and backward scattered light) of laser light by the fundus Ef, fluorescence using laser light as excitation light, and scattered light thereof. The return light passes through the pupil and is emitted from the eye E to be inspected. The return light from the eye E to be inspected travels in the same direction as the outward path in the opposite direction and is guided to the detector 135. The return light guided to the detector 135 is detected by the light receiving element. The light receiving element photoelectrically converts the detected return light and outputs an electric signal (light receiving signal).

The above process corresponds to the measurement of one point of the fundus Ef, and corresponds to the measurement in the irradiation region of a single spot light with respect to the fundus Ef. In this embodiment, the moving mechanism 30 rotates the optical unit 20 around the pupil position R (one-dimensionally, two-dimensionally, or three-dimensionally), and the scanning optical system 21 in the optical unit 20 causes spot light. Deflection (one-dimensional or two-dimensional). As a result, the irradiation region of the spot light in the fundus Ef is moved. That is, in this embodiment, the fundus Ef for acquiring the SLO image is scanned by combining the rotation of the optical unit 20 by the moving mechanism 30 and the deflection by the scanning optical system 21.

Similarly, when the OCT image is acquired by the measurement unit 10, the measurement light LS based on the light L0 output from the OCT light source 151 (light source 40) is two-dimensionally measured by the optical unit 20 moved by the moving mechanism 30. Be biased. The two-dimensionally changed measurement light LS is projected from the optical axis direction of the optical unit 20 to the fundus Ef through the pupil of the eye E to be inspected. The measurement light LS incident on the eye E to be inspected is scattered at the anterior segment of the eye E to be inspected. Further, a part of the laser light incident on the eye E to be inspected passes through the pupil and is imaged as spot light on the fundus Ef.

The return light of the measurement light LS projected on the fundus Ef is scattered (including reflection) at various depth positions of the eye E to be inspected. The return light of the measurement light LS including such backscattered light travels in the same path as the outward path in the opposite direction, is combined with the reference light LR to become the interference light LC, and is guided to the detector 155. The return light guided to the detector 155 is detected by the light receiving element. The light receiving element photoelectrically converts the detected return light and outputs an electric signal (light receiving signal).

The above process corresponds to the measurement of one point of the fundus Ef, and corresponds to the measurement in the irradiation region of a single spot light with respect to the fundus Ef. As described above, the moving mechanism 30 rotates the optical unit 20 around the pupil position R, and the scanning optical system 21 in the optical unit 20 deflects the spot light. As a result, the irradiation region of the spot light in the fundus Ef is moved. That is, by combining the rotation of the optical unit 20 by the moving mechanism 30 and the deflection by the scanning optical system 21, scanning of the fundus Ef for acquiring an OCT image is executed.

[Processing system]
FIG. 5 shows a configuration example of the processing unit 70 of the ophthalmologic imaging apparatus 1 according to the embodiment. In FIG. 5, the same parts as those in FIGS. 1 to 4 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

(Control unit)
The processing unit 70 (processing system of the ophthalmologic imaging apparatus 1) of FIG. 1 is mainly composed of a control unit 200. The control unit 200 controls each unit of the ophthalmologic imaging apparatus 1. 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, for example, a microprocessor. A computer program for controlling the ophthalmologic imaging apparatus is stored in the storage unit 202 in advance. 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 the control process.

Controls for the objective lens system 110 include control for the moving mechanism 110D for moving the objective lens 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 composed of, for example, a pulse motor. The transmission mechanism is composed of, for example, a combination of gears or a rack and pinion. 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 and off the light source, adjusting the amount of light, adjusting the aperture, and the like. The control of the optical scanner 136 includes the control of the scanning position and the scanning range by the optical scanner 136X, the control of the scanning position and the scanning range by the optical scanner 136Y, and the like. Control of the detector 135 includes exposure adjustment, gain adjustment, and detection rate adjustment of the detection element.

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 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 amount of light, adjusting the aperture, and the like. The control of the optical scanner 142 includes the control of the scanning position and the scanning range by the optical scanner 142X, the control of the scanning position and the 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 composed of, for example, a pulse motor. The transmission mechanism is composed of, for example, a combination of gears or a rack and pinion. 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 the 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 composed of, for example, a pulse motor. The transmission mechanism is composed of, for example, a combination of gears or a rack and pinion. 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, control of the anterior segment imaging camera 123, and the like. Control of the anterior segment illumination light source 121 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. Control of the anterior segment imaging camera 123 includes exposure adjustment, gain adjustment, and imaging rate adjustment of the image sensor.

As control for the optical system 100, control of the drive unit 30D for driving the moving mechanism 30 that moves the optical system 100 (including the dichroic mirrors DM1A, DM1B, and the anterior segment imaging system 120) in the X, Y, and Z directions, etc. There is. The main control unit 201 controls the drive unit 30D by sending a control signal to the actuator.

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

The alignment control unit 201A controls the execution of alignment for aligning the optical system 100 with respect to the eye E to be inspected. The alignment control unit 201A controls the drive unit 30D so that the amount of misalignment detected based on the bright spot image obtained by the alignment system 60 is canceled, so that the position of the optical system 100 with respect to the eye E to be inspected is canceled. Align (XY direction, Z direction).

Further, the alignment control unit 201A can control the moving mechanism 30 (driving unit 30D) and the moving mechanism 110D based on the anterior eye portion image of the eye E to be inspected obtained by the anterior eye portion photographing system 120. The alignment control unit 201A specifies, for example, a feature portion in the anterior segment image of the eye E to be inspected obtained by the anterior segment imaging system 120, and the amount of deviation between the position of the specified feature portion and the predetermined target position. The amount of movement of the optical system 100 or the like is obtained so that The alignment control unit 201A aligns the optical system 100 with respect to the eye E to be inspected by controlling the drive unit 30D based on the obtained movement amount (XY directions). The target position may be a predetermined position or a position in the anterior segment image designated by using the UI unit 230.

The alignment control unit 201A specifies, for example, the in-focus state (blurring condition) of the anterior segment image of the eye E to be inspected obtained by the anterior segment imaging system 120, and the specified in-focus state is the desired in-focus state. It is possible to obtain the amount of movement of the objective lens system 110 in the Z direction so as to be. The alignment control unit 201A aligns the optical system 100 and the objective lens system 110 with respect to the eye E to be inspected by controlling the movement mechanisms 100D and 110D based on the obtained movement amount (Z direction). It should be noted that two or more cameras are used to photograph the anterior segment of the eye from different directions, and the focused state is three-dimensionally specified from the two or more images provided with parallax, and the specified focused state is desired. The amount of movement of the objective lens system 110 in the Z direction may be obtained so as to be in the focused state.

The alignment control unit 201A may align the objective lens system 110 with respect to the eye E to be inspected (Z direction) by controlling the movement mechanism 110D based on the SLO image obtained by the SLO optical system 130. In this case, the alignment control unit 201A identifies the in-focus state (blurring degree) of the acquired SLO image, and makes the specified in-focus state a desired in-focus state in the Z direction of the objective lens system 110. 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 201B controls tracking of the SLO image of the eye E to be inspected obtained by the SLO optical system 130. The tracking control unit 201B specifies, for example, a feature portion in the SLO image at a predetermined timing, and when the position of the specified feature portion changes, the movement amount is obtained so that the deviation 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 OCT image of the eye E to be inspected obtained by the OCT optical system 140 based on the SLO image. The tracking control unit 201B specifies, for example, a feature portion in the SLO image at a predetermined timing, and when the position of the specified feature portion changes, the movement amount is obtained so that the deviation 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 optometry target control unit 201C controls the optometry optical system 50. The fixation target control unit 201C controls turning on and off of the fixation light source (for internal fixation and external fixation), and moves the projection position (fixation position) of the fixation target on the fundus Ef. It is possible. When the optical system 100 is rotated around the pupil position R of the eye to be inspected E by the moving mechanism 30, the fixation target control unit 201C is an optical system so that the direction of the eye to be inspected E (eyeball) is stationary with respect to the optical axis O. The presentation position of the fixation target is moved in conjunction with the movement of 100. Further, the fixation target control unit 201C may move the presentation position of the fixation target without rotating the optical system 100 by the movement mechanism 30. Even in this case, the orientation of the eye E to be inspected and the orientation of the optical axis O can be relatively changed.

The display control unit 201D causes various information to be displayed on the UI unit 230, which will be 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, and information after data processing by the data processing unit 220.

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

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

The data processing unit 220 includes an image composition unit 220A. The image synthesizing unit 220A has two or more images acquired by using the SLO optical system 130 or the OCT optical system 140 in a state where the relative orientations of the orientation of the eye E to be examined and the orientation of the optical axis O of the optical system 100 are different from each other. By synthesizing (SLO image or OCT image), a composite image in which ghost (noise) is suppressed is generated. Specifically, the image synthesizing unit 220A corresponds the partial region of the first image to the partial region in the second image with respect to the first image and the second image acquired in a state where the relative orientations are different from each other. A composite image is generated by replacing with a region. In this case, after the first image is acquired when the relative orientation of the eye E to be inspected and the orientation of the optical axis O of the optical system 100 are in a predetermined relative orientation, the optical system 100 is operated by the moving mechanism 30. Is swiveled by a predetermined angle, and the second image is acquired when the relative orientation is set different from the relative orientation when the first image is acquired. Further, after the first image is acquired in a state where the fixation target is presented at a predetermined position without rotating the optical system 100 by the moving mechanism 30, the presentation position is different from that when the first image is acquired. The second image may be acquired with the fixation target presented. Thereby, it is possible to acquire a composite image in which the ghost drawn on one of the first image and the second image is suppressed by using the other image.

6A and 6B show explanatory views showing an example of the operation of the image synthesizing unit 220A. 6A and 6B show the operation contents when the image synthesizing unit 220A synthesizes two SLO images, but the same applies to the operation when synthesizing two OCT images.

For example, by rotating the optical system 100 by the moving mechanism 30 or changing the presentation position of the fixation target, the first SLO image IA and the second SLO image IB are acquired as shown in FIG. 6A. The first SLO image IA is an SLO image of a predetermined angle f acquired by using the SLO optical system 130 when the eye to be inspected E and the optical axis O are set in the first relative orientation. The second SLO image IB is an SLO image having a predetermined angle of view f acquired by using the SLO optical system 130 when the second relative orientation is set different from the first relative orientation.

Ghosts (noise) N1 and N2 caused by surface reflection of the cornea of the objective lens and the eye E to be inspected are visualized in the predetermined regions (central regions including the central portion) of the first SLO image IA and the second SLO image IB, respectively. There is. Ghosts N1 and N2 are drawn in a predetermined shape at a predetermined position in an image determined by the arrangement relationship of optical elements and the eye E to be inspected.

The image compositing unit 220A generates a composite image IC in which the first partial region of the first SLO image IA is replaced with a region corresponding to the first partial region in the second SLO image IB. The image synthesizing unit 220A further performs a process of replacing the second partial region of the second SLO image IB with the region corresponding to the second partial region in the first SLO image IA.

Hereinafter, for convenience of explanation, a case where the turning direction is the X direction will be described. For example, in FIG. 6B, the lateral direction represents the turning direction (difference direction between the first relative direction and the second relative direction) of the optical system 100 by the moving mechanism 30. When the optical system 100 is rotated by the angle α by the moving mechanism 30, the first SLO image IA is represented as an image having an angle of view 0 to f as shown in FIG. 6B, and the second SLO image IB is the angle of view α. It is represented as an image having an angle of view (f + α). The angle α (difference between the first relative orientation and the second relative orientation) is determined from the position and size in the image in which the noises N1 and N2 are drawn.

First, the image synthesizing unit 220A divides each of the first SLO image IA and the second SLO image IB into three strip-shaped regions in the turning direction. Here, it is divided into a region from the angle of view 0 to the angle of view α and two regions in which the remaining region is divided in the turning direction. Specifically, the first SLO image IA includes a region BR1a (IA (0 to α)) from the angle of view 0 to the angle of view α and a region BR1b ((f + α) / 2) from the angle of view α to the angle of view ((f + α) / 2). It is divided into an IA (α to (f + α) / 2)) and a region BR1c (IA ((f + α) / 2) to f) from the angle of view ((f + α) / 2) to the angle of view f. The noise N1 is included in the region Br1b. Similarly, the second image SLO image IB has a region BR2a (IB (α to (f + α) / 2)) from the angle of view α to the angle of view ((f + α) / 2) and the angle of view ((f + α) / 2). ) To the area BR2b (IB ((f + α) / 2) to f) from the angle of view f to the area BR2c (IB (f to (f + α))) from the angle of view f to the angle of view (f + α). To. The noise N2 is included in the region BR2b. That is, the angle α is determined so that the noise N1 is included in the region BR1a and the noise N2 is included in the region BR2b. The region BR2a is a partial region corresponding to the region BR1b. The region BR1c is a partial region corresponding to the region BR2b. For example, when the widths W of the noises N1 and N2 in the turning direction are equal to each other, W <(f−α) / 2 may be set so that the noise is included in each of the region BR1b and the region BR2b. That is, α <(f-2W) may be satisfied. For example, α> W may be set so that the noise N2 moved in the turning direction with respect to the noise N1 does not overlap with the noise N1.

Next, the image synthesizing unit 220A performs a known alignment process of the first SLO image IA and the second SLO image IB, and generates a composite image IC in which both the aligned images are combined. At this time, the region BR1b of the first SLO image is replaced with the region BR2a of the second SLO image IB. Further, the image synthesizing unit 220A replaces the region BR2b of the second SLO image IB with the region BR1c of the first SLO image IA for the first SLO image IA. As a result, the composite image IC has the area BR1a from the angle of view 0 to the angle of view α, the area BR2a from the angle of view α to the angle of view ((f + α) / 2), and the angle of view ((f + α) / 2) to the angle of view. Up to f, the image is the region BR1c, and from the angle of view f to the angle of view (f + α), the image is the region BR2c. As described above, the image synthesizing unit 220A can generate a composite image IC based on the angle α. As a result, in the generated composite image IC, ghosts drawn in a known shape at at least one of the images of the first SLO image IA and the second SLO image IB are suppressed. Further, the composite image IC is newly acquired as an image having a wider angle of view than the respective angles of view of the first SLO image IA and the second SLO image IB.

The image synthesizing unit 220A is not only a ghost drawn in a known shape at a known position in at least one of the first image (first SLO image IA) and the second image (second SLO image IB), but also the one. It is possible to generate a composite image in which ghosts are suppressed and drawn in an arbitrary shape at an arbitrary position in the image of. In this case, the image synthesizing unit 220A specifies the position and shape of the ghost that is commonly depicted in both the first image and the second image based on the pixel values. The image synthesizing unit 220A identifies the corresponding area in the second image corresponding to the area in which the ghost is drawn in the first image, and in the first image corresponding to the area in which the ghost is drawn in the second image. Identify the corresponding area. The image synthesizing unit 220A replaces the region in which the ghost is drawn in the first image with the corresponding region in the second image, and replaces the region in which the ghost is drawn in the second image with the corresponding region in the first image. By doing so, a composite image is generated. As a result, in the composite image, the ghost drawn in an arbitrary shape at an arbitrary position in at least one of the first image and the second image is suppressed. Further, the composite image is newly acquired as an image having a wider angle of view than the respective angles of view of the first image and the second image.

Further, the image synthesizing unit 220A sets the first partial region of the first OCT image acquired by using the OCT optical system 140 when the eye E to be examined and the optical axis O are set in the first relative orientation. 2 A composite image may be generated in which a region corresponding to the first partial region in the second OCT image acquired by using the OCT optical system 140 when the orientation is set is replaced. In this case as well, the image synthesizing unit 220A may further perform a process of replacing the second partial region of the second OCT image with the region in the first OCT image corresponding to the second partial region.

(UI part)
The UI (User Interface) unit 230 has a function for exchanging information between the user and the ophthalmologic imaging 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. Operating devices include various hardware keys and / or software keys. The control unit 200 can receive the 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 operating device and at least a part of the display device. The touch panel display is an example.

The moving mechanism 30, the optometry optical system 50, the optometry target control unit 201C, and the control unit 200 are examples of the "change unit" according to the embodiment. The first SLO image IA is an example of the "first image" according to the embodiment, and the second SLO image IB is an example of the "second image" according to the embodiment.

[motion]
The operation of the ophthalmologic imaging apparatus according to the embodiment will be described.

FIG. 7 shows an example of the operation of the ophthalmologic imaging apparatus according to the embodiment. FIG. 7 shows a flow chart of an operation example when the ophthalmologic imaging apparatus according to the embodiment acquires an SLO image.

(S1)
First, the objective lens unit 110A for the wide-angle shooting mode is set on the optical axis O. For example, a user such as an examiner, a subject, a doctor, or a patient manually sets the objective lens unit 110A on the optical axis O. The ophthalmologic imaging apparatus can shift the operation to S2 based on the operation performed by the user on the UI unit 230. Further, the ophthalmologic imaging apparatus detects the type of the objective lens unit arranged on the optical axis O, and when it is determined that the detected type corresponds to the imaging mode registered in advance, the ophthalmologic imaging apparatus. The operation of may be shifted to S2.

(S2)
In a state where the relative orientation of the direction of the eye to be inspected E and the direction of the optical axis O of the optical system 100 is set to a predetermined direction by the moving mechanism 30, the control unit 200 is set to the predetermined direction by the anterior eye portion photographing system 120. An image of the anterior segment of the eye is acquired by photographing the anterior segment of the eye.

(S3)
The alignment control unit 201A controls the movement mechanism 30 (drive unit 30D) based on the anterior eye portion image acquired in S2 as described above, so that the positions of the optical system 100 and the objective lens system 110 with respect to the eye E to be inspected. Align (X direction, Y direction and Z direction). Alternatively, the alignment system 60 may be used to perform the alignment.

(S4)
The control unit 200 moves the optical scanner 136 to a predetermined initial position.

(S5)
The control unit 200 turns on the SLO light source 131 and controls the optical scanner 136 to start scanning the fundus Ef of the eye E to be inspected with the light from the SLO light source 131. The SLO image forming unit 210A forms an SLO image of the fundus Ef based on the detection result of the fundus reflected light by the detector 135. In S5, the tracking control unit 201B may start tracking control for the SLO image.

(S6)
The control unit 200 swivels the optical system 100 by a designated angle α by controlling the drive unit 30D. The designated angle α may be an angle designated by the user using the UI unit 230, or may be a predetermined angle.

(S7)
The control unit 200 again controls the optical scanner 136 to start scanning the fundus Ef of the eye E to be inspected with the light from the SLO light source 131. The SLO image forming unit 210A forms an SLO image of the fundus Ef based on the detection result of the fundus reflected light by the detector 135. In addition, before the start of the scan, the anterior segment may be photographed in the same manner as in S2 and S3, and the alignment may be performed based on the obtained anterior segment image.

(S8)
Next, the control unit 200 causes the image compositing unit 220A to perform a compositing process using the SLO image acquired in S5 and the SLO image acquired in S7. The image compositing unit 220A generates a composite image using two SLO images as shown in FIG. 6B.

(S9)
Next, the display control unit 201D causes the display device included in the UI unit 230 to display the composite image generated in S8. This completes the operation of the ophthalmologic imaging device (end).

<Modification example>
In the above-described embodiment, the two images are in a state in which the relative orientations of the direction of the eye E to be inspected and the orientation of the optical axis O of the optical system 100 are different from each other by rotating the optical system 100 by a designated angle α by the moving mechanism 30. Although the case of acquiring the above is described, the configuration according to the embodiment is not limited to this.

FIG. 8 shows a functional block diagram of a schematic configuration of an ophthalmologic imaging apparatus according to a modified example of the embodiment.

The configuration of the ophthalmologic imaging apparatus 1a according to the modified example differs from the configuration of the ophthalmologic imaging apparatus 1 according to the embodiment in that the measurement unit 10a is provided with the angle detection unit 25 and the processing unit 70a is based on the angle detection unit 25. The point is that processing is performed based on the detection result. The angle detection unit 25 detects the angle of the optical system 100 swiveled by the moving mechanism 30 with reference to the reference direction. The control unit 200a of the processing unit 70a obtains the difference between the angle detected by the angle detection unit 25 before turning and the angle detected by the angle detection unit 25 after turning, so that the angle at which the optical system 100 is turned is obtained. (Equivalent to the specified angle α) can be obtained. As a result, the obtained angle corresponds to the difference between the orientation of the eye E to be inspected and the first relative orientation and the second relative orientation of the optical axis O. Therefore, as in the embodiment, the image synthesizing unit 220A It becomes possible to generate a composite image according to the turning angle of the optical system 100 obtained by the control unit 200a.

The angle detection unit 25 may detect the difference in angle before and after turning by the moving mechanism 30. The angle detection unit 25 and the control unit 200a, or the angle detection unit 25 is an example of the “detection unit” according to the modified example of the embodiment.

According to this modification, at least one of the two images acquired by photographing in a state where the relative orientations of the orientation of the eye E to be inspected and the orientation of the optical axis O of the optical system 100 are different from each other, as in the embodiment. It is possible to obtain a composite image in which the ghost drawn in the image of is suppressed. This composite image is newly acquired as an image having a wider angle of view than the respective angles of view of the two images.

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

The ophthalmologic imaging apparatus (ophthalmic imaging apparatus 1, 1a) according to the embodiment includes an optical system (optical system 100), a changing unit (moving mechanism 30, or an optometry optical system 50, an optometry target control unit 201C, and a control unit). 200) and an image synthesizing unit (image synthesizing unit 220A). The optical system is used to photograph the fundus (fundus Ef) of the eye to be inspected (eye to be inspected E). The changing unit relatively changes the direction of the eye to be inspected and the direction of the optical axis (optical axis O) of the optical system. The image synthesizing unit captures a partial region (region BR1b) of the first image (first SLO image IA) acquired by using the optical system when the eye to be inspected and the optical axis are set in the first relative orientation. A region (region BR2a) corresponding to the above partial region in the second image (second SLO image IB) acquired by using the optical system when the second relative orientation different from the first relative orientation is set. A composite image (composite image IC) replaced with is generated.

According to such a configuration, the first image and the second image obtained in a state where the orientation of the eye to be inspected and the relative orientation of the optical axis O of the optical system are different from each other are acquired, and a partial region of the first image is obtained. Since the composite image is generated by replacing the region corresponding to the partial region in the second image, it is possible to acquire the composite image from which the ghost (noise) drawn in the partial region of the first image is removed. ..

Further, in the ophthalmologic imaging apparatus according to the embodiment, the image synthesizing unit further performs a process of replacing a partial region (region BR2b) of the second image with a region (region BR1c) in the first image corresponding to the partial region. May be good.

According to such a configuration, the partial area of the second image is further replaced with the area corresponding to the partial area in the first image to generate a composite image, so that the partial area of the first image is drawn. It is possible to acquire a composite image in which not only the ghost to be formed but also the ghost (noise) drawn in the partial region of the second image is removed.

Further, in the ophthalmologic imaging apparatus according to the embodiment, the partial region may be a central region including the central portion of the image.

With such a configuration, it is possible to acquire a composite image in which the depiction of ghosts due to the surface reflection of the objective lens or the cornea of the eye to be inspected is suppressed.

Further, in the ophthalmologic imaging apparatus according to the embodiment, the optical system includes an objective lens (objective lens system 110), and the changing portion is a position (pupil position R or its own) separated from the objective lens by a predetermined distance along the optical axis. A moving mechanism (moving mechanism 30) that rotates the optical system around the vicinity position) may be included.

According to such a configuration, the orientation of the eye to be inspected and the relative orientation of the optical axis O of the optical system are changed by rotating the optical system around a predetermined position. The depiction of ghosts is suppressed, and it becomes possible to acquire a wider-angle composite image.

Further, in the ophthalmologic imaging apparatus according to the embodiment, the modified portion includes a fixation target (fixation optical system 50) that presents the fixation target to the eye to be examined through an optical path formed by the optical system, and presentation of the fixation target. A control unit (control unit 200, fixation target control unit 201C) that changes the position may be included.

According to such a configuration, the relative orientation of the direction of the eye to be inspected and the optical axis O of the optical system is changed by changing the presentation position of the fixation target, so that the device can be miniaturized. , The depiction of ghosts is suppressed, and it becomes possible to acquire a wider-angle composite image.

Further, in the ophthalmologic imaging apparatus according to the embodiment, the partial region may be a region having a predetermined size and a default shape including the center of the image acquired by the optical system.

According to such a configuration, it is possible to acquire a composite image in which the drawing of a ghost having a known shape at a known position is suppressed.

Further, in the ophthalmologic imaging apparatus according to the embodiment, the image synthesizing unit may specify a partial region based on the pixel value of the image acquired by the optical system.

According to such a configuration, it is possible to acquire a composite image in which the drawing of a ghost of an arbitrary shape is suppressed at an arbitrary position.

Further, in the ophthalmologic imaging apparatus according to the embodiment, the image synthesizing unit may determine a partial region based on the difference between the first relative orientation and the second relative orientation.

According to such a configuration, the partial region is determined according to the difference between the first relative orientation and the second relative orientation, so that the ghost drawn in the acquired image can be accurately drawn. It becomes possible to suppress.

Further, the ophthalmologic imaging apparatus according to the embodiment may include a detection unit (angle detection unit 25 and control unit 200a, or angle detection unit 25) for detecting the difference between the first relative orientation and the second relative orientation. Good.

According to such a configuration, since the detection unit detects the difference between the first relative orientation and the second relative orientation, the relative orientation between the orientation of the eye to be inspected and the orientation of the optical axis of the optical system. It is possible to accurately suppress the depiction of ghosts depicted in the image according to the amount of change in.

<Others>
The embodiments shown above are merely examples for carrying out the present invention. A person who intends to carry out the present invention can make arbitrary modifications, omissions, additions, etc. within the scope of the gist of the present invention.

In the above-described embodiment, the case where the configuration of the optical system 100 is the configuration shown in FIGS. 2 and 4 has been described, but 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 an optotype while the eye to be inspected is fixed.

In the above-described embodiment, the case where the configuration of the objective lens system 110 is the configuration shown in FIGS. 2 to 4 has been described, but the configuration of the objective lens system according to the embodiment is not limited to this.

In the above-described embodiment, the case where the image synthesizing unit 220A generates a composite image as shown in FIGS. 6A and 6B has been described, but the embodiment is not limited to the processing content by the image synthesizing unit 220A. For example, the image synthesizing unit 220A may generate a composite image in which noise depiction is suppressed by adding or subtracting two images having different relative orientations.

1, 1a Ophthalmologic imaging device 10, 10a Measurement unit 20 Optical unit 21 Scanning optical system 22 Projection system 23 Light receiving system 25 Angle detection unit 30 Moving mechanism 30D Drive unit 40 Light source 50 Optometry optical system 60 Alignment system 70, 70a Processing unit 100 Optical system 200, 200a Control unit 210 Image forming unit 220 Data processing unit 220A Image synthesis unit 230 UI unit E Eye to be inspected Ef Fundus

Claims (3)

An optical system for photographing the fundus of the eye to be inspected,
A change part that relatively changes the direction of the eye to be inspected and the direction of the optical axis of the optical system,
When the eye to be inspected and the optical axis are set to the first relative orientation, the partial region of the first image acquired by using the optical system and the noise is drawn is different from the first relative orientation. An image compositing unit that generates a composite image replaced with a region corresponding to the partial region in the second image acquired by using the optical system when the second relative orientation is set.
Including
The image synthesizing unit is an ophthalmologic photographing apparatus that identifies the partial region based on the pixel value of the first image acquired by the optical system. An optical system for photographing the fundus of the eye to be inspected,
A change part that relatively changes the direction of the eye to be inspected and the direction of the optical axis of the optical system,
When the eye to be inspected and the optical axis are set to the first relative orientation, the partial region of the first image acquired by using the optical system and the noise is drawn is different from the first relative orientation. An image compositing unit that generates a composite image replaced with a region corresponding to the partial region in the second image acquired by using the optical system when the second relative orientation is set.
Including
The image synthesizing unit is an ophthalmologic imaging apparatus that determines the partial region based on the difference between the first relative orientation and the second relative orientation. The ophthalmologic imaging apparatus according to claim 2 , further comprising a detection unit that detects the difference between the first relative orientation and the second relative orientation.

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