JP7460406B2 - Ophthalmological device, its control method, and program - Google Patents

Description

The present invention relates to an ophthalmologic apparatus, a control method thereof, and a program.

In recent years, screening tests are being performed using ophthalmic devices. It is expected that such ophthalmic devices will also be used for self-examination, so there is a demand for them to be even smaller and lighter.

For example, Patent Document 1 and Patent Document 2 disclose an ophthalmologic apparatus configured to illuminate a subject's eye in a pattern and receive the returned light using a rolling shutter method using an image sensor. This ophthalmological apparatus can acquire an image of the eye to be examined with a simple configuration by adjusting the illumination pattern and the timing of light reception by the image sensor.

U.S. Pat. No. 7,831,106 US Patent No. 8237835

So-called flare may occur in such an image of the eye to be examined. Generally, reducing the amount of illumination light is effective for reducing flare.

However, in this type of ophthalmic device, there is a trade-off between the amount of illumination light and the imaging time. Specifically, if the amount of illumination light is reduced, the imaging time must be extended to compensate for the reduced amount of light. However, if the imaging time is extended, the image quality will deteriorate due to fixational eye movements of the subject's eye during imaging. In contrast, if the amount of illumination light is increased, the imaging time can be shortened. However, as the amount of light increases, flare is more likely to occur.

The ease with which such flare occurs varies depending on the eye to be examined. Therefore, it is extremely difficult to obtain high-quality images of the eye to be examined while suppressing flare, which occurs in different ways depending on the eye to be examined.

The present invention was made in view of the above circumstances, and one of its purposes is to provide a new technique for obtaining high-quality images of the eye to be examined while suppressing the occurrence of flare. It is in.

A first aspect of some embodiments includes a first light source, an illumination optical system that generates slit-shaped illumination light using light from the first light source, and a fundus of an eye to be examined by deflecting the illumination light. guiding the return light from the fundus to an image sensor configured to capture the reception result of the return light of the illumination light corresponding to the irradiation position of the illumination light on the fundus in a rolling shutter manner; an imaging optical system; an acquisition unit that acquires a fundus image of the eye to be examined using light from a second light source; and a flare determination unit that determines whether flare has occurred by analyzing the fundus image of the eye to be examined. , controlling at least one of the first light source, the illumination optical system, the optical scanner, the photographing optical system, and the image sensor based on the first determination result obtained by the flare determination unit; a control unit that executes imaging time optimization control that changes imaging conditions so that the imaging time of the eye is shortened; and an image forming unit that forms an image of the fundus based on the light reception result captured by the image sensor. , the control unit is configured to determine the second determination result obtained by the flare determination unit using the fundus image acquired by the acquisition unit under the imaging conditions changed by the imaging time optimization control. When it is determined that the flare has occurred based on the imaging conditions, the imaging conditions are returned to the imaging conditions before the change, and the fundus is adjusted based on the light reception result captured by the image sensor under the imaging conditions before the change. The ophthalmological apparatus causes the image forming section to form an image of the ophthalmologic apparatus.

In a second aspect of some embodiments, in the first aspect, the illumination optical system includes a slit that can be placed at a fundus conjugate position that is approximately optically conjugate with the fundus and has a slit-shaped first opening whose opening shape is changeable, and an iris diaphragm that can be placed at an iris conjugate position that is approximately optically conjugate with the iris of the subject's eye between the first light source and the slit and has a second opening whose opening shape is changeable, and when it is determined based on the first determination result that the flare has not occurred, the control unit controls the illumination optical system so that the size of the opening shape of at least one of the first opening and the second opening is increased.

In a third aspect of some embodiments, in the first or second aspect, the photographing optical system includes a photographing diaphragm that can be placed at an iris conjugate position that is approximately optically conjugate with the iris of the subject's eye and has a third opening whose opening shape is changeable, and when it is determined based on the first determination result that no flare has occurred, the control unit controls the photographing optical system so that the size of the opening shape of the third opening is increased.

In a fourth aspect of some embodiments, in the third aspect, the photographing diaphragm is arranged in the direction of the optical path of the illumination optical system and the optical axis passing through the third opening. and a hole mirror configured to guide the illumination light reflected in the peripheral area of the third opening to the fundus of the eye.

In a fifth aspect of some embodiments, in any of the first to fourth aspects, when it is determined based on the first determination result that no flare has occurred, the control unit controls at least one of the illumination optical system, the optical scanner, and the image sensor so as to shorten the image capturing time of the fundus.

In a sixth aspect of some embodiments, in any of the first to fifth aspects, the control unit controls the imaging time until it is determined that the flare has occurred based on the second determination result. Execute optimization control repeatedly.

In a seventh aspect of some embodiments, in any of the first to sixth aspects, the acquisition unit includes the second light source and captures the light from the second light source captured by the image sensor. The fundus image is acquired based on the result of receiving the returned light.

In an eighth aspect of some embodiments, in any of the first to seventh aspects, the control unit executes flare optimization control to change the shooting conditions so as to eliminate the occurrence of the flare by controlling at least one of the first light source, the illumination optical system, the optical scanner, the shooting optical system, and the image sensor when it is determined based on the first determination result that the flare has occurred, and executes the shooting time optimization control when it is determined based on the first determination result that the flare has not occurred.

In a ninth aspect of some embodiments, in any of the first to eighth aspects, the image sensor is a CMOS image sensor.

A tenth aspect of some embodiments includes a first light source, an illumination optical system that generates slit-shaped illumination light using light from the first light source, and a fundus of the eye to be examined by deflecting the illumination light. guiding the return light from the fundus to an image sensor configured to capture the reception result of the return light of the illumination light corresponding to the irradiation position of the illumination light on the fundus in a rolling shutter manner; This is a method of controlling an ophthalmological apparatus, including a photographing optical system and an acquisition unit that acquires a fundus image of the eye to be examined using light from a second light source. The method for controlling an ophthalmological apparatus includes a first flare determination step of determining the presence or absence of flare by analyzing a fundus image of the eye to be examined, and a first determination result obtained in the first flare determination step. Photographing time in which photographing conditions are changed so that the photographing time of the fundus is further shortened by controlling at least one of the first light source, the illumination optical system, the optical scanner, the photographing optical system, and the image sensor. The control step includes a control step of executing optimization control, and an image forming step of forming an image of the fundus based on the light reception result captured by the image sensor, and the control step is performed by the imaging time optimization control. When it is determined that the flare has occurred based on the second determination result obtained in the first flare determination step using the fundus image acquired by the acquisition unit under changed imaging conditions; The imaging conditions are returned to the imaging conditions before the change, and the image forming step forms an image of the fundus based on the light reception result captured by the image sensor under the imaging conditions before the change.

In an eleventh aspect of some embodiments, in the tenth aspect, the illumination optical system is a slit-like optical system that can be disposed at a fundus conjugate position that is optically approximately conjugate with the fundus, and that has a changeable opening shape. a slit in which an aperture is formed, and a second slit which can be arranged at an iris conjugate position optically substantially conjugate with the iris of the eye to be examined between the first light source and the slit, and whose aperture shape can be changed. an iris diaphragm in which an aperture is formed, and when it is determined that the flare does not occur based on the first determination result, the control step includes controlling the first aperture and the second aperture. The illumination optical system is controlled so that the size of at least one aperture shape is increased.

In a twelfth aspect of some embodiments, in the tenth or eleventh aspects, the photographing optical system includes a photographing diaphragm that can be placed at an iris conjugate position that is approximately optically conjugate with the iris of the subject's eye and has a third opening whose opening shape is changeable, and when it is determined based on the first determination result that no flare has occurred, the control step controls the photographing optical system so that the size of the opening shape of the third opening is increased.

In a thirteenth aspect of some embodiments, in any of the tenth to twelfth aspects, the control step controls at least one of the illumination optical system, the optical scanner, and the image sensor so as to shorten the photographing time of the fundus when it is determined based on the first determination result that no flare has occurred.

In a fourteenth aspect of some embodiments, in any of the tenth to thirteenth aspects, the control step may control the imaging time until it is determined that the flare has occurred based on the second determination result. Execute optimization control repeatedly.

In a fifteenth aspect of some embodiments, in any of the tenth to fourteenth aspects, the control step includes controlling the first control step when it is determined that the flare has occurred based on the first determination result. Executing flare optimization control that changes photographing conditions so that the flare does not occur by controlling at least one of a light source, the illumination optical system, the optical scanner, the photographing optical system, and the image sensor; The imaging time optimization control is executed when it is determined that the flare does not occur based on the first determination result.

In a sixteenth aspect of some embodiments, in any of the tenth to fifteenth aspects, the image sensor is a CMOS image sensor.

A seventeenth aspect of some embodiments is a program that causes a computer to execute each step of the method for controlling an ophthalmic device according to any one of the tenth to sixteenth aspects.

Note that it is possible to arbitrarily combine the configurations according to the plurality of aspects described above.

This invention provides a new technology for obtaining high-quality images of the examinee's eye while suppressing the occurrence of flare.

It is a schematic diagram showing an example of composition of an optical system of an ophthalmologic device concerning an embodiment. It is a schematic diagram showing an example of composition of a control system of an ophthalmologic device concerning an embodiment. It is a schematic diagram showing an example of composition of an optical system of an ophthalmologic device concerning an embodiment. 1 is a schematic diagram illustrating an example of the configuration of an optical system of an ophthalmic apparatus according to an embodiment. It is a schematic diagram showing an example of composition of an optical system of an ophthalmologic device concerning an embodiment. It is a schematic diagram showing an example of composition of an optical system of an ophthalmologic device concerning an embodiment. It is a schematic diagram showing an example of composition of an optical system of an ophthalmologic device concerning an embodiment. 4A to 4C are diagrams illustrating the operation of the ophthalmologic apparatus according to the embodiment. 4A to 4C are diagrams illustrating the operation of the ophthalmologic apparatus according to the embodiment. FIG. 2 is an explanatory diagram of the operation of the ophthalmologic apparatus according to the embodiment. It is a schematic diagram showing an example of composition of a control system of an ophthalmologic device concerning an embodiment. 2 is a schematic diagram showing an example of the configuration of a control system of an ophthalmic apparatus according to an embodiment. FIG. It is a schematic diagram showing a flow of an example of operation of an ophthalmological device concerning an embodiment. 5 is a schematic diagram illustrating a flow of an example of an operation of the ophthalmologic apparatus according to the embodiment. FIG. 4A to 4C are diagrams illustrating the operation of the ophthalmologic apparatus according to the embodiment. It is a schematic diagram showing a flow of an example of operation of an ophthalmological device concerning an embodiment. FIG. 2 is an explanatory diagram of the operation of the ophthalmologic apparatus according to the embodiment.

An example of an embodiment of an ophthalmic device, a control method thereof, and a program according to the present invention will be described in detail with reference to the drawings. Note that the contents of the documents described in this specification may be appropriately used as the contents of the following embodiment.

The ophthalmological apparatus according to the embodiment illuminates a predetermined part of the eye to be examined while moving the irradiation position (illumination area, irradiation range) of the slit-shaped illumination light, and the light receiving elements are arranged one-dimensionally or two-dimensionally. The returned light from a predetermined region is received using an image sensor. The return light reception result is read out from the light receiving element at the return light reception position corresponding to the illumination light irradiation position in synchronization with the movement timing of the illumination light irradiation position. In some embodiments, the predetermined site is the anterior segment or the posterior segment of the eye. The anterior segment of the eye includes the cornea, iris, crystalline lens, ciliary body, and Chin's zonules. The posterior segment includes the vitreous body, the fundus, or its vicinity (retina, choroid, sclera, etc.).

A method for controlling an ophthalmologic apparatus according to an embodiment includes one or more steps for realizing processing executed by a processor (computer) in an ophthalmologic apparatus according to an embodiment. The program according to the embodiment causes the processor to execute each step of the method for controlling an ophthalmological apparatus according to the embodiment.

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

Below, we will explain the case where the ophthalmic device according to the embodiment mainly acquires an image of the fundus of the test eye. Furthermore, unless otherwise specified below, the shooting time using the image sensor corresponds to the exposure time of the light receiving element of the image sensor, and the "shooting time" and the "exposure time" may be expressed as being the same.

[Optical system configuration]
1 to 10 are schematic diagrams of an example of the configuration of an ophthalmic apparatus according to an embodiment. FIG. 1 shows an example of the configuration of an optical system of an ophthalmic apparatus 1 according to an embodiment. FIG. 2 shows a block diagram of an example of the configuration of a control system (processing system) of the ophthalmic apparatus 1 according to an embodiment. FIGS. 3, 4A, and 4B show a schematic configuration example of the iris diaphragm 21 of FIG. 1 as viewed from the direction of the optical axis O. FIGS. 5A and 5B show a schematic configuration example of the slit 22 of FIG. 1 as viewed from the direction of the optical axis O. FIGS. 6 to 8 show explanatory diagrams of the operation of the ophthalmic apparatus according to an embodiment. FIG. 9 shows a block diagram of a configuration example of the data processing unit 200 of FIG. 2. FIG. 10 shows a block diagram of a configuration example of the analysis unit 220 of FIG. 9. In FIGS. 1 to 10, the same reference numerals are given to the same parts, and the description will be omitted as appropriate.

The ophthalmologic apparatus 1 includes a first light source 10 , a second light source 11 , an illumination optical system 20 , an optical scanner 30 , a projection optical system 35 , a photographing optical system 40 , and an imaging device 50 . In some embodiments, illumination optical system 20 includes at least one of first light source 10 , second light source 11 , optical scanner 30 , and projection optical system 35 . In some embodiments, the imaging optical system 40 includes an imaging device 50. In some embodiments, the projection optical system 35 or the imaging optical system 40 includes an optical scanner 30.

In the embodiment, while the optical system (illumination optical system 20, optical scanner 30, projection optical system 35, photographing optical system 40) including the imaging device 50 is shared, a slit-shaped light generated from the light from the second light source 11 is used. Based on the analysis results of the fundus image obtained using light, the imaging conditions for obtaining a high-quality image of the fundus Ef using the slit-shaped light generated from the light from the first light source 10 are optimized. . In some embodiments, the fundus image is obtained from another device different from the ophthalmic device 1.

(First light source 10)
The first light source 10 includes a visible light source that generates light in the visible region. For example, the first light source 10 generates light having a center wavelength in a wavelength range of 420 nm to 700 nm. Such a first light source 10 includes, for example, an LED (Light Emitting Diode), an LD (Laser Diode), a halogen lamp, or a xenon lamp. In some embodiments, the first light source 10 includes a white light source or a light source capable of outputting light of each RGB color component. The first light source 10 is arranged at a position that is optically non-conjugate with each of the fundus Ef and the iris.

(Second light source 11)
The second light source 11 includes an infrared light source that generates light in the infrared region. For example, the second light source 11 generates light having a central wavelength in the near-infrared wavelength range of 700 nm to 1000 nm. Such a second light source 11 includes, for example, an LED, an LD, a halogen lamp, or a xenon lamp. In some embodiments, a single light source that can switch between outputting light in the visible region and light in the infrared region realizes the functions of the first light source 10 and the second light source 11. The second light source 11 is disposed at a position that is optically non-conjugate with each of the fundus Ef and the iris.

A half mirror 12 is disposed between the first light source 10 and the illumination optical system 20. The optical path of the light from the second light source 11 is substantially coaxially coupled with the optical path of the light from the first light source 10 by the half mirror 12. The light from the first light source 10 passes through the half mirror 12 and is guided to the illumination optical system 20. The light from the second light source 11 is reflected by the half mirror 12 and is guided to the illumination optical system 20.

(Illumination optical system 20)
The illumination optical system 20 generates slit-shaped illumination light using light from the first light source 10 or the second light source 11. Illumination optical system 20 guides the generated illumination light to optical scanner 30.

The illumination optical system 20 includes an iris diaphragm 21, a slit 22, and a relay lens 23. Light from the first light source 10 or the second light source 11 passes through an opening formed in the iris diaphragm 21, passes through an opening formed in the slit 22, and is transmitted through the relay lens 23. The relay lens 23 includes one or more lenses. The light transmitted through the relay lens 23 is guided to the optical scanner 30.

(iris diaphragm 21)
The iris diaphragm 21 (specifically, an opening described below) can be arranged at a position that is optically substantially conjugate with the iris (pupil) of the eye E to be examined. The iris diaphragm 21 has one or more openings formed at positions away from the optical axis O. For example, as shown in FIG. 3, openings 21A and 21B having a predetermined thickness are formed in the iris diaphragm 21 along the circumferential direction centered on the optical axis O. The opening formed in the iris diaphragm 21 defines the incident position (incident shape) of the illumination light on the iris of the eye E to be examined. For example, by forming the openings 21A and 21B as shown in FIG. 3, when the pupil center of the eye E to be examined is placed on the optical axis O, It is possible to make the illumination light enter the eye from a point symmetrical to the center.

In addition, by changing the relative position between the first light source 10 and the opening formed in the iris diaphragm 21, it is possible to change the light quantity distribution of the light passing through the opening formed in the iris diaphragm 21.

The iris diaphragm 21 according to the embodiment can change the size of the shape of at least one of the openings 21A and 21B.

For example, as shown in FIG. 4A, the iris diaphragm 21 is provided so as to be substantially orthogonal to a rotation axis O' that is substantially parallel to the optical axis O and includes a turret. The turret is rotatably provided around a rotation axis O'. The turret is provided with a plurality of iris diaphragms on a circumference centered on the rotation axis O'. By rotating the turret around the rotation axis O', it is possible to selectively arrange a plurality of iris diaphragms (iris diaphragms 21 ₁ to 21 ₃ in FIG. 4A) on the optical axis O. The turret can be rotated automatically or manually. For example, a drive mechanism (21D) under control from the control unit 100, which will be described later, can rotate the turret around a rotation axis O'. In FIG. 4A, an iris diaphragm 21 ₁ in which openings 21A ₁ and 21B ₁ are formed, an iris diaphragm 21 ₂ in which openings 21A ₂ and 21B ₂ are formed, and an iris diaphragm 21 in which openings 21A ₃ and 21B ₃ are formed. The size of the opening shape increases in the order of ₃ .

Further, as shown in FIG. 4B, for example, the iris diaphragm 21 includes an optical member 21C1 that is provided substantially perpendicular to the optical axis O and has openings 21A and 21B formed therein, and an optical member _21C1 that is provided substantially perpendicularly to the optical axis O. It includes a disc-shaped shielding plate _21C2 whose radius can be changed. A part of the circumference of the shielding plate _21C2 constitutes the inner diameter of the openings 21A and 21B. A mechanism (not shown) can change the radius of the shielding plate _21C2 . The radius of the shielding plate _21C2 can be changed automatically or manually. For example, a mechanism under control from the control unit 100, which will be described later, can change the length of the radius of the shielding plate _21C2 . By changing the size of the inner diameter of the openings 21A, 21B in this way, it is possible to change the size of the opening shape of the openings 21A, 21B of the iris diaphragm 21.

Although FIG. 4B describes a case in which the size of the inner diameter of the openings 21A and 21B is changed, the size of the outer diameter of the openings 21A and 21B may be changed. . In this case, it is possible to change the size of the aperture shape of the apertures 21A, 21B of the iris diaphragm 21 by changing the size of the outer diameter of the apertures 21A, 21B.

In this way, by reducing the size of the opening shape of at least one of the openings 21A and 21B, the amount of illumination light passing through the iris diaphragm 21 can be reduced. By increasing the size of the opening shape of at least one of the openings 21A and 21B, the amount of illumination light passing through the iris diaphragm 21 can be increased.

In some embodiments, the size of the opening shape of the openings 21A, 21B of the iris diaphragm 21 is changed depending on the size of the pupil region of the test eye E. For example, in the case of a test eye E with a large pupil region, the exposure time (photographing time) of the image sensor 51 can be shortened by increasing the size of the opening shape of the openings 21A, 21B of the iris diaphragm 21. For example, in the case of a test eye E with a small pupil region, the size of the opening shape of the openings 21A, 21B of the iris diaphragm 21 can be reduced to compensate for the reduction in the amount of illumination light by changing the photographing conditions.

In some embodiments, the image of the anterior segment of the test eye E is analyzed to determine the size of the pupil region, and the size of the opening shape of the openings 21A and 21B of the iris diaphragm 21 is changed based on the determined size of the pupil region.

(Slit 22)
The slit 22 (specifically, an opening described later) can be arranged at a position that is approximately optically conjugate with the fundus Ef of the subject's eye E. For example, an opening is formed in the slit 22 in a direction corresponding to a line direction (row direction) read out from an image sensor 51 described later by a rolling shutter method. The opening formed in the slit 22 defines an irradiation pattern of illumination light on the fundus Ef of the subject's eye E.

The slit 22 is movable in the optical axis direction of the illumination optical system 20 by a drive mechanism (drive mechanism 22D to be described later). The drive mechanism moves the slit 22 in the optical axis direction under control from a control unit 100, which will be described later. For example, the control unit 100 controls the drive mechanism according to the condition of the eye E to be examined. Thereby, the position of the slit 22 can be moved according to the condition of the eye E to be examined (specifically, the refractive power and the shape of the fundus Ef).

In some embodiments, the slit 22 is configured such that at least one of the position and shape of the opening can be changed depending on the condition of the eye E without being moved in the optical axis direction. Such a function of the slit 22 is realized by, for example, a liquid crystal shutter.

The slit 22 in this embodiment allows the size of the opening shape of the opening to be changed.

For example, as shown in FIG. 5A, the slit 22 is provided so as to be substantially orthogonal to a rotation axis O'' that is substantially parallel to the optical axis O and includes a turret. The turret is rotatably provided around a rotation axis O''. The turret is provided with a plurality of slits on a circumference centered on the rotation axis O''. By rotating the turret around the rotation axis O'', it is possible to selectively arrange a plurality of slits (slits 22 ₁ to 22 ₃ in FIG. 5A) on the optical axis O. The turret can be rotated automatically or manually. For example, a drive mechanism (22D) under control from the control unit 100, which will be described later, can rotate the turret around a rotation axis O''. In FIG. 5A, the size of the opening shape increases in the order of slit 22 ₁ , slit 22 ₂ , and slit 22 ₃ .

Further, as shown in FIG. 5B, for example, the slit 22 includes shielding plates 22A and 22B that are slidably provided in a direction substantially perpendicular to the optical axis O. The shielding plates 22A and 22B are slid in mutually opposite directions so that the slit width is changed symmetrically with respect to the slit center line passing through the optical axis O. The shielding plates 22A and 22B are slid automatically or manually. For example, the drive mechanism (22D) slides the shielding plates 22A and 22B. For example, a drive mechanism (22D) under control from the control unit 100, which will be described later, slides the shielding plates 22A and 22B.

In this way, by reducing the width of the slit 22 (the size of the opening shape), the amount of illumination light passing through the slit 22 can be reduced. By increasing the width of the slit 22, the amount of illumination light passing through the slit 22 can be increased.

The light from the first light source 10 or the second light source 11 that passes through the opening formed in the iris diaphragm 21 is output as slit-shaped illumination light by passing through the opening formed in the slit 22. The slit-shaped illumination light passes through the relay lens 23 and is guided to the optical scanner 30.

(Optical scanner 30)
The optical scanner 30 is disposed at a position that is optically approximately conjugate with the iris of the subject's eye E. The optical scanner 30 deflects slit-shaped illumination light (slit-shaped light that has passed through an opening formed in the slit 22) that passes through the relay lens 23. Specifically, the optical scanner 30 deflects the slit-shaped illumination light for sequentially illuminating a predetermined illumination range of the fundus Ef while changing the deflection angle within a predetermined deflection angle range with the iris of the subject's eye E or its vicinity as the scanning center position, and guides the slit-shaped illumination light to the projection optical system 35. The optical scanner 30 is capable of deflecting the illumination light one-dimensionally or two-dimensionally.

In the case of one-dimensional deflection, the optical scanner 30 includes a galvano scanner that deflects the illumination light in a predetermined deflection angle range based on a predetermined deflection direction. In the case of two-dimensional deflection, the optical scanner 30 includes a first galvano scanner and a second galvano scanner. The first galvano scanner deflects the illumination light so as to move the irradiation position of the illumination light in a horizontal direction perpendicular to the optical axis of the illumination optical system 20. The second galvano scanner deflects the illumination light deflected by the first galvano scanner so as to move the irradiation position of the illumination light in a vertical direction perpendicular to the optical axis of the illumination optical system 20. Examples of scanning modes for moving the illumination light irradiation position by the optical scanner 30 include horizontal scanning, vertical scanning, cross scanning, radial scanning, circular scanning, concentric scanning, and spiral scanning.

(Projection optical system 35)
The projection optical system 35 guides the illumination light deflected by the optical scanner 30 to the fundus Ef of the eye E to be examined. In the embodiment, the projection optical system 35 guides the illumination light deflected by the optical scanner 30 to the fundus Ef through an optical path that is coupled to the optical path of the photographing optical system 40 by a hole mirror 45 as an optical path coupling member, which will be described later. .

The projection optical system 35 includes a relay lens 41, a black dot plate 42, a reflecting mirror 43, and a relay lens 44. Each of the relay lenses 41 and 44 includes one or more lenses.

(Black dot plate 42)
The black dot plate 42 is disposed at a position that is approximately optically conjugate with the lens surface of the objective lens 46 or its vicinity. This makes it possible to prevent reflected light from the lens surface of the objective lens 46 from being guided to the imaging device 50.

In such a projection optical system 35, the illumination light deflected by the optical scanner 30 passes through the relay lens 41, passes through the black spot plate 42, and is reflected by the reflecting mirror 43 toward the hole mirror 45.

(Photographing optical system 40)
The photographing optical system 40 guides the illumination light that has been guided through the projection optical system 35 to the fundus Ef of the eye E to be examined, and also guides the return light of the illumination light from the fundus Ef to the imaging device 50.

In the photographing optical system 40, the optical path of the illumination light from the projection optical system 35 and the optical path of the return light of the illumination light from the fundus Ef are combined. By using the hole mirror 45 as an optical path coupling member that couples these optical paths, it is possible to pupil-divide the illumination light and its return light.

The photographing optical system 40 includes a hole mirror 45, an objective lens 46, a focusing lens 47, a relay lens 48, and an imaging lens 49. Each of relay lenses 48 includes one or more lenses.

(Hole mirror 45)
The hole mirror 45 has a hole formed therein, which is located on the optical axis of the photographing optical system 40. The hole of the hole mirror 45 is located at a position that is approximately optically conjugate with the iris of the subject's eye E. The hole mirror 45 reflects illumination light from the projection optical system 35 toward the objective lens 46 in the peripheral area of the hole. Such a hole mirror 45 functions as a photographing aperture.

That is, the hole mirror 45 connects the optical path of the illumination optical system 20 (projection optical system 35) and the optical path of the photographing optical system 40 arranged in the direction of the optical axis passing through the hole, and also It is configured to guide the illumination light reflected at the fundus Ef.

The hole mirror 45 according to the embodiment can change the size of the opening shape of the hole (opening) using a known mechanism. In some embodiments, a known mechanism under control from the control unit 100 described below changes the size of the opening shape of the hole of the hole mirror 45. In some embodiments, the hole mirror 45 includes a reflecting member in which a hole is formed in the center region, and an aperture member disposed inside or near the hole of the reflecting member, and the hole mirror 45 includes a control unit 100 described below. A known mechanism controlled by the diaphragm changes the size of the opening shape of the hole by driving the diaphragm member.

In this way, by reducing the size of the opening shape of the hole in the hole mirror 45, the amount of return light of the illumination light passing through the hole can be reduced. By increasing the size of the opening shape of the hole in the hole mirror 45, the amount of return light of the illumination light passing through the hole can be increased.

(Focusing lens 47)
The focusing lens 47 can be moved in the optical axis direction of the photographing optical system 40 by a moving mechanism (not shown). The moving mechanism moves the focusing lens 47 in the optical axis direction under the control of a control unit 100 (described later). This allows the return light of the illumination light that has passed through the hole of the hole mirror 45 to be imaged on the light receiving surface of the image sensor 51 of the imaging device 50 according to the state of the subject's eye E.

In such a photographing optical system 40, the illumination light from the projection optical system 35 is reflected toward the objective lens 46 in the peripheral area of the hole formed in the hole mirror 45. The illumination light reflected in the peripheral area of the hole mirror 45 is refracted by the objective lens 46, enters the eye through the pupil of the eye E, and illuminates the fundus Ef of the eye E.

The return light of the illumination light from the fundus Ef is refracted by the objective lens 46, passes through the hole in the hole mirror 45, transmits through the focusing lens 47, transmits through the relay lens 48, and is imaged by the imaging lens 49 on the light receiving surface of the image sensor 51 of the imaging device 50.

(Imaging device 50)
The imaging device 50 includes an image sensor 51 that receives return light of the illumination light guided from the fundus Ef of the subject's eye E through the imaging optical system 40. The imaging device 50 is controlled by a control unit 100 described later and is capable of outputting the result of receiving the return light.

(Image sensor 51)
The image sensor 51 functions as a pixelated light receiver. The light receiving surface (detection surface, imaging surface) of the image sensor 51 can be placed at a position that is optically approximately conjugate with the fundus Ef.

The light reception result by the image sensor 51 is captured and read out using a rolling shutter method. In some embodiments, a control unit 100, which will be described later, controls the reading of light reception results by controlling the image sensor 51. In some embodiments, the image sensor 51 can automatically output light reception results for a predetermined line along with information indicating the light reception position.

Such an image sensor 51 includes a CMOS image sensor. In this case, the image sensor 51 includes a plurality of pixels in which a group of pixels (light receiving elements) arranged in the row direction is arranged in the column direction. Specifically, the image sensor 51 includes a plurality of pixels arranged two-dimensionally, a plurality of vertical signal lines, and a horizontal signal line. Each pixel includes a photodiode (light receiving element) and a capacitor. The plurality of vertical signal lines are provided for each group of pixels in the column direction (vertical direction) perpendicular to the row direction (horizontal direction). Each vertical signal line is selectively electrically connected to a pixel group in which a charge corresponding to the light receiving result is accumulated. The horizontal signal line is selectively electrically connected to the plurality of vertical signal lines. Each pixel accumulates a charge corresponding to the light receiving result of the return light, and the accumulated charge is read out sequentially, for example, for each pixel group in the row direction. For example, a voltage corresponding to the charge accumulated in each pixel is supplied to the vertical signal line for each line in the row direction. The plurality of vertical signal lines are selectively electrically connected to the horizontal signal line. By performing the above-mentioned row-direction line-by-line readout operation in the vertical direction, it is possible to read out the light reception results of multiple pixels arranged two-dimensionally.

By capturing (reading) the results of receiving the return light from such an image sensor 51 using a rolling shutter method, a received light image corresponding to a desired virtual opening shape extending in the row direction is obtained. Such control is disclosed, for example, in the specification of U.S. Patent No. 8,237,835.

Figure 6 shows an explanatory diagram of the operation of the ophthalmologic apparatus 1 according to the embodiment. Figure 6 shows a schematic diagram of the irradiation range IP of the slit-shaped illumination light irradiated onto the fundus Ef and the virtual aperture range OP on the light receiving surface SR of the image sensor 51.

For example, the control unit 100 described below deflects slit-shaped illumination light formed by the illumination optical system 20 using the optical scanner 30. Thereby, in the fundus Ef, the irradiation range IP of the slit-shaped illumination light is sequentially moved (shifted) in a direction (eg, vertical direction) orthogonal to the slit direction (eg, row direction, horizontal direction).

On the light-receiving surface SR of the image sensor 51, a virtual aperture range (aperture area) OP is set by, for example, changing pixels to be captured line by line by the control unit 100, which will be described later. It is desirable that the aperture range OP is wider than the light receiving range IP' or the light receiving range IP' of the return light of the illumination light on the light receiving surface SR. For example, the control unit 100, which will be described later, executes movement control of the aperture range OP in synchronization with movement control of the illumination light irradiation range IP. Thereby, it is possible to obtain a high-quality image of the fundus Ef with a strong contrast with a simple configuration without being affected by unnecessary scattered light.

Figures 7 and 8 show schematic examples of control timing for the rolling shutter method for the image sensor 51. Figure 7 shows an example of the timing of read control for the image sensor 51. Figure 8 shows the movement control timing of the illumination light irradiation range IP (light receiving range IP') superimposed on the read control timing of Figure 7. In Figures 7 and 8, the horizontal axis represents the number of rows in the image sensor 51, and the vertical axis represents time.

7 and 8, for convenience of explanation, the image sensor 51 is described as having 1920 rows, but the configuration according to the embodiment is not limited to the number of rows. Further, in FIG. 8, for convenience of explanation, it is assumed that the slit width (width in the row direction) of the slit-shaped illumination light is 40 rows.

The row-direction readout control includes reset control, exposure control, charge transfer control, and output control. The reset control is a control for initializing the amount of charge accumulated in the pixels in the row direction. The exposure control is a control for shining light on the photodiode and accumulating a charge corresponding to the amount of light received in the capacitor. The charge transfer control is a control for transferring the amount of charge accumulated in the pixel to the vertical signal line. The output control is a control for outputting the amount of charge accumulated in multiple vertical signal lines via the horizontal signal line. That is, as shown in FIG. 7, the readout time T of the amount of charge accumulated in the pixels in the row direction is the sum of the time Tr required for the reset control, the time (exposure time) Te required for the exposure control, the time Tc required for the charge transfer control, and the time Tout required for the output control.

In FIG. 7, the read (capture) start timing (start timing of time Tc) is shifted row by row to obtain the light reception results (amount of charge) accumulated in pixels of a desired range in the image sensor 51. For example, if the pixel range shown in FIG. 7 is an image for one frame, the frame rate FR is uniquely determined.

In this embodiment, the irradiation position on the fundus Ef of illumination light having a slit width corresponding to a plurality of rows is sequentially shifted in the direction corresponding to the column direction on the fundus Ef. When the width in the shift direction of the irradiation range IP' (an area corresponding to the illumination area on the fundus Ef) on the light receiving surface of the image sensor 51 has a width equal to the number of rows of 2 or more, the control unit 100, which will be described later, The optical scanner 30 is controlled so that the aperture range OP (opening area) is shifted in the shift direction in units of the number of rows.

For example, as shown in FIG. 8, the irradiation position of the illumination light on the fundus Ef is shifted row by row in a direction corresponding to the column direction for each predetermined shift time Δt. The shift time Δt is obtained by dividing the exposure time Te of the pixel in the image sensor 51 by the slit width of the illumination light (e.g., the number of rows of the slit width = 40) (Δt = Te/40). Synchronized with the timing of the movement of this irradiation position, the timing of starting to read out each row of pixels is delayed and started for each row by shift time Δt. This makes it possible to obtain high-quality images of the fundus Ef with strong contrast with simple control in a short time.

In some embodiments, the image sensor 51 consists of one or more line sensors.

[Control system configuration]
As shown in FIG. 2, the control system of the ophthalmologic apparatus 1 is configured around a control section 100. Note that at least a part of the configuration of the control system may be included in the ophthalmologic apparatus 1.

(Control unit 100)
The control unit 100 controls each part of the ophthalmologic apparatus 1. Control unit 100 includes a main control unit 101 and a storage unit 102. The main control unit 101 includes a processor, and executes control processing for each unit of the ophthalmological apparatus 1 by executing processing according to a program stored in the storage unit 102.

(Main control unit 101)
The main control unit 101 controls the first light source 10, the second light source 11, the moving mechanism 10D, the illumination optical system 20, the optical scanner 30, the photographing optical system 40, and the imaging device 50. control and control of the data processing unit 200.

Control of the first light source 10 includes switching the light source on and off (or the wavelength range of light), and changing the amount of light from the light source.

Control of the second light source 11 includes switching the light source on and off (or the wavelength range of light) and controlling changes to the light intensity of the light source.

When the functions of the first light source 10 and the second light source 11 are realized by a single light source, the main control unit 101 can control switching between the functions of the first light source 10 and the second light source 11.

The movement mechanism 10D changes at least one of the position and orientation of the first light source 10 using a known mechanism. The main control unit 101 can change at least one of the relative position and relative orientation of the first light source 10 with respect to the iris diaphragm 21 and the slit 22.

The control of the illumination optical system 20 includes the control of the drive mechanisms 21D and 22D. The drive mechanism 21D changes the size of the opening shape of at least one of the openings 21A and 21B of the iris diaphragm 21. The main control unit 101 can change the size of the opening shape of at least one of the openings 21A and 21B of the iris diaphragm 21 by controlling the drive mechanism 21D.

The drive mechanism 22D moves the slit 22 in the optical axis direction of the illumination optical system 20 and changes the slit width of the slit 22.

The main controller 101 controls the drive mechanism 22D according to the state of the subject's eye E, thereby placing the slit 22 at a position corresponding to the state of the subject's eye E. The state of the subject's eye E includes the shape of the fundus Ef, the refractive power, and the axial length. The refractive power can be obtained from a known ocular refractive power measuring device such as that disclosed in JP-A-61-293430 or JP-A-2010-259495. The axial length can be obtained from the measurement value of a known axial length measuring device or an optical coherence tomography.

For example, first control information in which the position of the slit 22 on the optical axis of the illumination optical system 20 is previously associated with the refractive power is stored in the storage unit 102. The main control unit 101 refers to the first control information to identify the position of the slit 22 corresponding to the refractive power, and controls the drive mechanism 22D so that the slit 22 is positioned at the identified position.

Here, as the slit 22 moves, the light amount distribution of light passing through the opening formed in the slit 22 changes. At this time, as described above, the main controller 101 can change the position and orientation of the first light source 10 by controlling the moving mechanism 10D.

The main control unit 101 can also change the size of the slit width of the slit 22 by controlling the drive mechanism 22D.

Control of the optical scanner 30 includes controlling the angle of the deflection surface that deflects the illumination light. By controlling the angular range of the deflection surface, it is possible to control the scan range (scan start position and scan end position). The scan speed can be controlled by controlling the speed at which the angle of the deflection surface changes.

The control of the imaging optical system 40 includes the control of the moving mechanism 47D. The moving mechanism 47D moves the focusing lens 47 in the optical axis direction of the imaging optical system 40. The main control unit 101 can control the moving mechanism 47D based on the analysis results of the image acquired using the image sensor 51. The main control unit 101 can also control the moving mechanism 47D based on the operation contents of the user using the operation unit 110 described below.

The control of the imaging device 50 includes the control of the image sensor 51. The control of the image sensor 51 includes the control for reading out the light reception results using the rolling shutter method (for example, setting the light reception size corresponding to the size of the illumination pattern). The control of the image sensor 51 also includes reset control, exposure control, charge transfer control, output control, etc. It is possible to change the time Tr required for reset control, the time (exposure time) Te required for exposure control, the time Tc required for charge transfer control, the time Tout required for output control, etc.

The control of the data processing unit 200 includes various image processing and analysis processing for the light reception results obtained from the image sensor 51. Image processing includes noise removal processing for light reception results and brightness correction processing for making it easier to identify a predetermined region depicted in a light reception image based on the light reception results. The analysis process includes a process for specifying a focus state.

(Data processing unit 200)
The data processing section 200 includes an image forming section 210 and an analyzing section 220, as shown in FIG.

(Image forming unit 210)
The image forming unit 210 can form a light receiving image corresponding to an arbitrary aperture range based on the light receiving result read out from the image sensor 51 by the rolling shutter method. The image forming unit 210 can sequentially form light receiving images corresponding to the aperture range, and form an image of the subject's eye E from the formed multiple light receiving images.

The image forming unit 210 can irradiate the fundus Ef with illumination light generated using light from the first light source 10, and form an image (photographed image) of the fundus Ef based on the light reception result of the return light captured by the image sensor 51 using the rolling shutter method. The image forming unit 210 can also irradiate the fundus Ef with illumination light generated using light from the second light source 11, and form a fundus image (IR image) based on the light reception result of the return light captured by the image sensor 51 using the rolling shutter method.

(Analysis unit 220)
For example, the analysis unit 220 performs a predetermined analysis process on the fundus image formed by the image forming unit 210. The predetermined analysis process includes a determination process for changing photographing conditions, and the like. Specifically, the analysis unit 220 performs a determination process for changing the photographing conditions so as to obtain a photographed image of higher quality by analyzing the IR image.

As shown in FIG. 10, such an analysis section 220 includes a flare determination section 221, a fixation micromovement determination section 222, and a light amount determination section 223.

(Flare determination unit 221)
The flare determination unit 221 determines whether or not a flare has occurred by analyzing an image. Specifically, the flare determination unit 221 determines whether or not a flare has occurred by analyzing a fundus image (IR image) formed based on a light reception result captured by the image sensor 51 using light from the second light source 11.

In some embodiments, the flare determination unit 221 identifies an area of pixels having a predetermined brightness level or higher based on the brightness components of the pixels in the fundus image, and determines that a flare has occurred when the size of the identified area is a predetermined size or higher, and determines that a flare has not occurred when the size of the identified area is less than the predetermined size. In some embodiments, the flare determination unit 221 determines that a flare has occurred when it is determined that the shape of the identified area approximately matches a predetermined shape, and determines that a flare has not occurred when it is determined that the shape of the identified area does not approximately match the predetermined shape.

(Fixational Eye Movement Determination Unit 222)
The fixational eye movement determination unit 222 determines whether the fixational eye movement is large (small) or not by analyzing the image. Specifically, the fixational eye movement determination unit 222 determines whether the fixational eye movement is large (small) or not by analyzing a fundus image (IR image) formed based on the light reception result captured by the image sensor 51 using the light from the second light source 11.

In some embodiments, the fixational eye movement determination unit 222 identifies a characteristic area in the fundus image and determines whether or not the fixational eye movement is large based on the displacement of the identified characteristic area. For example, the fixational eye movement determination unit 222 determines that the fixational eye movement is large when the displacement of the characteristic area is equal to or greater than a predetermined amount of movement, and determines that the fixational eye movement is small when the displacement of the characteristic area is less than the predetermined amount of movement. The characteristic area may be the optic disc, macula, blood vessels, or lesions in the fundus.

(Light amount determination unit 223)
The light amount determination unit 223 determines whether or not it is possible to increase the amount of light output from the first light source 10. The light amount determination unit 223 determines whether or not there is a margin in the light source capability based on a predetermined maximum value of the output light amount of the first light source 10 and the current output light amount of the first light source 10, thereby determining whether or not there is a margin in the light source capability. For example, when it is determined that there is a margin in the light source capability of the first light source 10, the light amount determination unit 223 determines that it is possible to increase the amount of light output from the first light source 10. For example, when it is determined that there is no margin in the light source capability of the first light source 10, the light amount determination unit 223 determines that it is impossible to increase the amount of light output from the first light source 10.

The data processing unit 200 includes a processor and implements the above functions by performing processing according to a program stored in a storage unit or the like. In some embodiments, a processor corresponding to each unit constituting the data processing unit 200 is included, and each processor realizes the function of each unit constituting the data processing unit 200.

In some embodiments, the first light source 10 includes two or more light sources. In this case, each of the two or more light sources is provided corresponding to two or more openings formed in the iris diaphragm 21 or two or more openings formed in the slit 22. The main control unit 201 can change at least one of the position and orientation (the orientation in the direction in which the light quantity distribution is maximized) of each light source by controlling a movement mechanism provided corresponding to each of the two or more light sources.

(Memory unit 102)
The storage unit 102 stores various computer programs and data. The computer programs include a calculation program and a control program for controlling the ophthalmic apparatus 1.

(Operation unit 110)
The operation unit 110 includes an operation device or an input device. The operation unit 110 includes buttons and switches (for example, an operation handle, an operation knob, etc.) provided on the ophthalmologic apparatus 1, and operation devices (such as a mouse, a keyboard, etc.). Further, the operation unit 110 may include any operation device or input device such as a trackball, an operation panel, a switch, a button, a dial, or the like.

(Display unit 120)
The display unit 120 displays the image of the subject's eye E generated by the data processing unit 200. The display unit 120 includes a display device such as a flat panel display such as a liquid crystal display (LCD). The display unit 120 may also include various display devices such as a touch panel provided on the housing of the ophthalmologic apparatus 1.

The operation unit 110 and the display unit 120 do not need to be configured as separate devices. For example, it is possible to use a device in which the display function and the operation function are integrated, such as a touch panel. In that case, the operation unit 110 is configured to include this touch panel and a computer program. The operation content for the operation unit 110 is input to the control unit 100 as an electrical signal. In addition, operations and information input may be performed using a graphical user interface (GUI) displayed on the display unit 120 and the operation unit 110. In some embodiments, the functions of the display unit 120 and the operation unit 110 are realized by a touch screen.

(Other configurations)
In some embodiments, the ophthalmic apparatus 1 further includes a fixation projection system. For example, the optical path of the fixation projection system is coupled to the optical path of the imaging optical system 40 in the optical system configuration shown in FIG. 1. The fixation projection system can present an internal fixation target or an external fixation target to the subject's eye E. When presenting an internal fixation target to the subject's eye E, the fixation projection system includes an LCD that displays the internal fixation target under control of the control unit 100, and projects the fixation light beam output from the LCD onto the fundus of the subject's eye E. The LCD is configured to be able to change the display position of the fixation target on its screen. By changing the display position of the fixation target on the LCD, it is possible to change the projection position of the fixation target on the fundus of the subject's eye E. The display position of the fixation target on the LCD can be specified by the user using the operation unit 110. In some embodiments, the fixation projection system is provided with an OLED instead of an LCD.

In some embodiments, the ophthalmic device 1 includes an alignment system. In some embodiments, the alignment system includes an XY alignment system and a Z alignment system. The XY alignment system is used to align the device optical system and the subject's eye E in a direction intersecting the optical axis of the device optical system (objective lens 46). The Z alignment system is used to align the device optical system and the subject's eye E in the direction of the optical axis of the ophthalmic device 1 (objective lens 46).

For example, the XY alignment system projects a bright spot (a bright spot in the infrared region or near-infrared region) onto the eye E to be examined. The data processing unit 200 acquires the anterior segment image of the subject's eye E on which the bright spot is projected, and determines the displacement between the bright spot image depicted in the acquired anterior eye segment image and the alignment reference position. The control unit 100 uses a moving mechanism (not shown) to relatively move the device optical system and the eye E in a direction intersecting the direction of the optical axis so that the determined displacement is canceled.

For example, the Z alignment system projects alignment light in the infrared region or near-infrared region from a position off the optical axis of the apparatus optical system, and receives the alignment light reflected from the anterior segment of the eye E to be examined. The data processing unit 200 identifies the distance of the eye E to be examined relative to the optical system of the apparatus from the light receiving position of the alignment light that changes depending on the distance of the eye E to be examined relative to the optical system of the apparatus. The control unit 100 uses a moving mechanism (not shown) to relatively move the device optical system and the eye E in the direction of the optical axis so that the specified distance becomes a desired working distance.

In some embodiments, the functionality of the alignment system is accomplished by two or more anterior segment cameras positioned off-axis of the device optics. For example, as disclosed in Japanese Unexamined Patent Publication No. 2013-248376, the data processing unit 200 analyzes anterior segment images of the subject's eye E obtained substantially simultaneously with two or more anterior segment cameras. , the three-dimensional position of the eye E to be examined is specified using known trigonometry. The control unit 100 moves the device optical system using a moving mechanism (not shown) so that the optical axis of the device optical system substantially coincides with the axis of the eye E and the distance of the device optical system to the eye E becomes a predetermined working distance. and the subject's eye E are moved relative to each other in three dimensions.

As described above, in the ophthalmological apparatus 1, the slit 22 (opening), the imaging site (fundus Ef), and the image sensor 51 (light receiving surface) are arranged at optically substantially conjugate positions. By moving the light-receiving aperture of the image sensor 51 and the irradiation position of the illumination light in conjunction with each other, the ophthalmologic apparatus 1 can obtain a clear image of the imaging site while suppressing the influence of unnecessary scattered light. Become.

The hole mirror 45 is an example of the "imaging aperture" according to the embodiment. The second light source 11, the half mirror 12, the illumination optical system 20, the optical scanner 30, the projection optical system 35, the photographing optical system 40, the imaging device 50, the control unit 100, and the image forming unit 210 are the “acquisition unit” according to the embodiment. ” is an example. The openings 21A and 21B formed in the iris diaphragm 21 are examples of "second openings" according to the embodiment. The opening formed in the slit 22 is an example of a "first opening" according to the embodiment. The hole formed in the hole mirror 45 is an example of the "third opening" according to the embodiment.

[motion]
Next, the operation of the ophthalmologic apparatus 1 will be described.

11, 12, and 14 show flowcharts of operation examples of the ophthalmologic apparatus 1 according to the embodiment. FIGS. 13 and 15 are explanatory diagrams of the operation of the ophthalmologic apparatus 1 according to the embodiment. FIG. 11, FIG. 12, and FIG. 14 represent flowcharts of operation examples of the ophthalmologic apparatus 1 according to the embodiment. FIG. 12 shows a flowchart of an example of the operation of step S7 in FIG. FIG. 14 shows a flowchart of an example of the operation of step S8 in FIG. FIG. 13 shows an explanatory diagram of the operation example of FIG. 12. FIG. 15 shows an explanatory diagram of the operation example of FIG. 14. The storage unit 102 stores computer programs for implementing the processes shown in FIGS. 11, 12, and 14. The main control unit 101 executes the processes shown in FIGS. 11, 12, and 14 by operating according to this computer program.

(S1: Start emitting light from the second light source)
First, the ophthalmologic apparatus 1 acquires an IR image using the second light source 11 in order to optimize the photographing conditions for acquiring a high-quality photographed image using the first light source 10 .

Specifically, the main controller 101 controls the second light source 11 to start emitting light. At this time, with the subject's face fixed to a face receiving part (not shown), the examiner may perform a predetermined operation on the operation part 110, causing the main controller 101 to project a fixation target onto a predetermined fixation position on the fundus Ef in a fixation projection system (not shown).

(S2: Start acquiring IR images)
Next, the main control unit 101 starts acquiring an IR image by controlling the optical scanner 30, the imaging device 50, and the image forming unit 210. At this time, the main control unit 101 can control the optical scanner 30 to scan an imaging area for acquiring an IR image with illumination light. In some embodiments, the main control unit 101 controls the optical scanner 30 to scan an area that is the same as an imaging area for acquiring a captured image described below with illumination light.

(S3: Alignment)
Next, the main control unit 101 executes alignment (XY alignment, Z alignment).

For example, the main control unit 101 controls an alignment system (not shown) to project a bright spot onto the eye E to be examined. The main control unit 101 identifies a bright spot image in the IR image acquired using the image sensor 51, and based on the amount of movement of the optical system corresponding to the displacement of the bright spot image with respect to a predetermined alignment reference position (reference range). Then, a moving mechanism (not shown) is controlled, and the optical system is moved relative to the eye E by the amount of movement. The main control unit 101 repeatedly executes this process.

In some embodiments, alignment is performed manually. For example, the main controller 101 causes the display unit 120 to display a composite image in which an image representing a predetermined alignment reference position (reference range) is superimposed on an IR image. A user such as an examiner operates the operation unit 110 while viewing the composite image displayed on the display unit 120. The user operates the operation unit 110 so as to cancel the displacement of a desired portion in the image relative to the predetermined alignment reference position. The main controller 101 controls a movement mechanism (not shown) based on an operation signal corresponding to the operation content on the operation unit 110.

(S4: Focus adjustment)
Next, the main control unit 101 executes focus adjustment.

In some embodiments, after the alignment in step S3 is completed, the process in step S4 is automatically performed. For example, when the displacement of the desired part with respect to the alignment reference position becomes less than or equal to a predetermined threshold, the main control unit 101 determines that the alignment in step S3 is completed, and executes the process in step S4.

In some embodiments, when the user performs a predetermined operation on the operation unit 110 in step S3, the main control unit 101 executes the process in step S4.

For example, the main control unit 101 acquires an IR image of the fundus Ef, and causes the data processing unit 200 to determine the focus state of the acquired IR image. The data processing unit 200 can determine the focus state of the IR image using a known method. For example, the data processing unit 200 determines the focus state of the IR image based on the slope of the luminance component of an edge region that defines a predetermined portion in a feature region of the IR image. The main control unit 101 specifies the amount of movement of the focusing lens 47 in the optical axis direction based on the determination result of the focus state by the data processing unit 200, and controls the movement mechanism 47D based on the specified amount of movement. When it is determined that the focus state of the IR image is not appropriate based on the determination result by the data processing unit 200, the main control unit 101 controls the moving mechanism 47D again, and it is determined that the focus state is appropriate. Repeat until.

In some embodiments, the focus state is done manually. For example, the main control unit 101 causes the display unit 120 to display an IR image. The user operates the operation unit 110 while viewing the IR image displayed on the display unit 120. The user operates the operation unit 110 so that the focus state of the IR image becomes appropriate. The main control unit 101 controls the moving mechanism 47D based on an operation signal corresponding to the content of the operation on the operation unit 110.

(S5: Flare judgment)
Next, the main control unit 101 causes the flare determination unit 221 to perform flare determination.

In some embodiments, after the focus adjustment in step S4 is completed, the process of step S5 is automatically executed. For example, when it is determined that the focus state is appropriate, the main control unit 101 determines that the focus adjustment in step S4 is completed, and executes the process of step S5.

In some embodiments, when the user performs a predetermined operation on the operation unit 110 in step S4, the main control unit 101 executes the processing of step S5.

As described above, the flare determination unit 221 determines whether flare has occurred by analyzing the IR image.

(S6: Flare occurred?)
The main control unit 101 determines whether flare has occurred in the IR image based on the determination result obtained by the flare determination process in step S5.

In step S6, when it is determined that flare has occurred in the IR image (S6: Y), the process of the ophthalmological apparatus 1 moves to step S7. On the other hand, when it is determined that no flare occurs in the IR image (S6: N), the process of the ophthalmological apparatus 1 moves to step S8.

(S7: Flare optimization control)
When it is determined in step S6 that flare occurs in the IR image (S6: Y), the main controller 101 executes flare optimization control. In the flare optimization control, the photographing conditions of the fundus Ef are optimized so that no flare occurs in the IR image (photographed image) of the fundus Ef. Details of step S7 will be described later.

Following step S7, processing in step S9 is executed.

(S8: Shooting time optimization control)
When it is determined in step S6 that flare does not occur in the IR image (S6: N), the main control unit 101 executes imaging time optimization control. In the imaging time optimization control, the imaging conditions of the fundus Ef are optimized so that the imaging time using the image sensor 51 is shortened within a range where no flare occurs in the IR image (photographed image) of the fundus Ef. Details of step S8 will be described later.

Following step S8, the process of step S9 is executed.

(S9: Stop emitting light from the second light source)
Following step S7 or step S8, the main control unit 101 executes step S9. In step S9, the main control unit 101 controls the second light source 11 to stop the second light source 11 from emitting light. As a result, the acquisition of the IR image started in step S2 is stopped.

(S10: Start emitting light from the first light source)
Subsequently, the ophthalmological apparatus 1 starts acquiring a photographed image of the fundus Ef under the photographing conditions optimized in step S7 or step S8.

Specifically, the main control unit 101 controls the first light source 10 so that the first light source 10 starts emitting light.

(S11: Obtain fundus image)
Next, the main control unit 101 controls the optical scanner 30, the imaging device 50, and the image forming unit 210 to start acquiring a captured image of the fundus Ef using the first light source 10. At this time, the main control unit 101 controls the optical scanner 30 to scan a predetermined imaging area on the fundus Ef with illumination light, and causes the image forming unit 210 to form a captured image of the fundus Ef.

This completes the operation of the ophthalmic device 1 (end).

In step S7 of FIG. 11, processing is executed as shown in FIG.

(S21: Received light amount reduction control)
First, the main control unit 101 controls at least one of the illumination optical system 20 and the photographing optical system 40 so that the amount of returned illumination light received by the image sensor 51 is reduced.

Control over the illumination optical system 20 includes control over the iris diaphragm 21 and control over the slit 22. Control over the imaging optical system 40 includes control over the hole mirror 45.

In a first example of control to reduce the amount of received light, the main control unit 101 controls the iris diaphragm 21. Specifically, as shown in FIG. 4A or 4B, the main control unit 101 controls the drive mechanism 21D to reduce the size of the opening shape of at least one of the openings 21A and 21B of the iris diaphragm 21 by a predetermined step. In some embodiments, the size of the opening shape is reduced by increasing the inner diameter of at least one of the openings 21A and 21B of the iris diaphragm 21. In some embodiments, the size of the opening shape is reduced by reducing the outer diameter of at least one of the openings 21A and 21B of the iris diaphragm 21.

In the second example of the control to reduce the amount of received light, the main control unit 101 controls the slit 22. Specifically, as shown in FIG. 5A or 5B, the main control unit 101 reduces the size of the opening (slit width) of the slit 22 by a predetermined step by controlling the drive mechanism 22D.

In a third example of control to reduce the amount of received light, the main control unit 101 controls the hole mirror 45. Specifically, the main control unit 101 controls a mechanism (not shown) to reduce the opening shape of the hole (opening) formed in the hole mirror 45 by a predetermined step.

In some embodiments, the main control unit 101 performs control to reduce the amount of received light by combining two or more of the first to third examples described above. In some embodiments, the main control unit 101 reduces the amount of received light by using any one of the first to third examples or a combination of two or more of the above-described examples 1 to 3, based on the flare determination result obtained in step S5. Take control.

(S22: Determine fixational eye movement)
Next, the main controller 101 causes the fixational eye movement determining section 222 to determine fixational eye movement.

The fixation micromovement determination unit 222 determines whether or not the fixation micromovement is small (large or not) with respect to the IR image as described above.

(S23: Is the fixation micromovement small?)
The main control unit 101 determines whether the fixation micromovement of the eye E to be examined is small based on the determination result obtained by the fixation micromovement determination process in step S22.

In step S23, when it is determined that the visual fixation micromovement is small (S23: Y), the operation of the ophthalmologic apparatus 1 moves to step S26. On the other hand, when it is determined that the fixation micromovement is not small (when it is determined that the fixation micromovement is large) (S23:N), the operation of the ophthalmologic apparatus 1 moves to step S24.

(S24: Determine light amount)
In step S23, when it is determined that the visual fixation micromovement is not small (S23: N), the main control section 101 causes the light amount determination section 223 to determine the light amount of the first light source 10.

As described above, the light amount determination unit 223 determines whether it is possible to increase the amount of light output from the first light source 10.

(S25: Is it possible to increase the light source light intensity?)
The main control unit 101 determines whether or not it is possible to increase the amount of light output from the first light source 10 based on the determination result obtained by the light source light amount determination process in step S24.

In step S25, when it is determined that the amount of light output from the first light source 10 can be increased (S25: Y), the operation of the ophthalmologic apparatus 1 moves to step S27. On the other hand, when it is determined that it is impossible to increase the amount of light output from the first light source 10 (S26: N), the operation of the ophthalmologic apparatus 1 moves to step S26.

(S26: Increase shooting time)
When it is determined that the fixation micromovement is small in step S23 (S23: Y), or when it is determined that it is impossible to increase the amount of light output from the first light source 10 in step S25 (S25: N ), the main control unit 101 performs control so that the imaging time using the image sensor 51 becomes longer by a predetermined step.

Specifically, the main control unit 101 controls the imaging time using the image sensor 51 by controlling the optical scanner 30 and the image sensor 51.

Figure 13 shows an explanatory diagram of an example of control of the image capture time using the image sensor 51 in step S26. In Figure 13, the vertical axis represents the number of pixels (number of rows) of the image sensor 51, and the horizontal axis represents time.

In the imaging time control example shown in FIG. 13, with the slit width Sw fixed, the main controller 101 controls the optical scanner 30 and the image sensor 51 to scan the illumination light irradiation area on the fundus Ef. The light receiving timing of the light receiving surface of the image sensor 51 is controlled.

That is, the main control unit 101 can shorten the imaging time using the image sensor 51 by increasing the scanning speed of the illumination light irradiation area on the fundus Ef (when changing from exposure time St1 to exposure time St0) ). Furthermore, the main control unit 101 can lengthen the imaging time using the image sensor 51 by lowering the scanning speed of the illumination light irradiation area on the fundus Ef (when changing from exposure time St0 to exposure time St1). ).

In step S26, the main control unit 101 can lengthen the imaging time using the image sensor 51 by lowering the scanning speed of the illumination light irradiation area on the fundus Ef.

(S27: Increase light source light intensity)
When it is determined in step S25 that it is possible to increase the amount of light output from the first light source 10 (S25: Y), the main control unit 101 controls the first light source 10 to The amount of light output from 10 is increased by a predetermined amount.

That is, in steps S23 to S27, when it is determined that the visual fixation micromovement is large and that the first light source 10 has room to increase the light amount, the light amount of the first light source 10 is increased in step S27. On the other hand, when it is determined that the visual fixation micromovement is small, or when it is determined that the first light source 10 has no margin for increasing the light intensity, the imaging time using the image sensor 51 is controlled to be longer in step S26. Ru.

(S28: Flare judgment)
Following step S26 or step S27, the main control unit 101 causes the flare determination unit 221 to perform flare determination.

The flare determination unit 221 determines whether flare has occurred by analyzing the IR image whose acquisition was started in step S2. Thereby, it is possible to determine whether flare has occurred in the IR image after the processing in step S26 or step S27.

(S29: Flare occurred?)
The main control unit 101 determines whether flare has occurred in the IR image based on the determination result obtained by the flare determination process in step S28.

When it is determined in step S29 that flare has occurred in the IR image (S29: Y), the process of the ophthalmic device 1 proceeds to step S21. On the other hand, when it is determined that flare has not occurred in the IR image (S21: N), the ophthalmic device 1 ends the process of step S7 in FIG. 11 (END).

As described above, the flare optimization control in step S7 of FIG. 11 is repeated until it is determined that no flare has occurred.

In step S8 of FIG. 11, processing is executed as shown in FIG.

(S31: Received light amount increase control)
First, the main control unit 101 controls at least one of the illumination optical system 20 and the photographing optical system 40 so that the amount of returned illumination light received by the image sensor 51 increases.

Control over the illumination optical system 20 includes control over the iris diaphragm 21 and control over the slit 22. Control over the photographing optical system 40 includes control over the hole mirror 45.

In a first example of control for increasing the amount of received light, the main control unit 101 controls the iris diaphragm 21. Specifically, as shown in FIG. 4A or 4B, the main control unit 101 controls the drive mechanism 21D to increase the size of the opening shape of at least one of the openings 21A and 21B of the iris diaphragm 21 by a predetermined step. In some embodiments, the size of the opening shape is increased by decreasing the inner diameter of at least one of the openings 21A and 21B of the iris diaphragm 21. In some embodiments, the size of the opening shape is increased by increasing the outer diameter of at least one of the openings 21A and 21B of the iris diaphragm 21.

In a second example of control for increasing the amount of received light, the main control unit 101 controls the slit 22. Specifically, as shown in FIG. 5A or 5B, the main control unit 101 controls the drive mechanism 22D to increase the size of the opening (slit width) of the slit 22 by a predetermined step.

In the third example of the control to increase the amount of received light, the main control unit 101 controls the hole mirror 45. Specifically, the main control unit 101 enlarges the opening shape of the hole (opening) formed in the hole mirror 45 by a predetermined step by controlling a mechanism (not shown).

In some embodiments, the main control unit 101 performs control to increase the amount of received light by combining two or more of the first to third examples described above. In some embodiments, the main control unit 101 increases the amount of received light by using any one of the first to third examples or a combination of two or more of the above-mentioned first to third examples based on the flare determination result obtained in step S5. Take control.

(S32: Shorten the shooting time)
Subsequently, the main control unit 101 performs control so that the imaging time using the image sensor 51 is shortened by a predetermined step.

Specifically, the main control unit 101 controls the shooting time using the image sensor 51 by controlling at least one of the illumination optical system 20, the optical scanner 30, and the image sensor 51.

FIG. 15 shows an explanatory diagram of an example of controlling the imaging time using the image sensor 51 in step S32. In FIG. 15, the vertical axis represents the number of pixels (number of rows) of the image sensor 51, and the horizontal axis represents time.

In the example of controlling the shooting time shown in FIG. 15, with the exposure time St fixed, the main control unit 101 controls the illumination optical system 20, the optical scanner 30, and the image sensor 51 to control the scanning of the illumination light irradiated area on the fundus Ef and the timing of light reception on the light receiving surface of the image sensor 51.

That is, by controlling the slit 22 in the illumination optical system 20 to increase the slit width, the main control unit 101 can increase the scanning speed of the illumination light irradiation area on the fundus Ef (from the slit width Sw1 to the slit width (when changing to Sw0). In this case, the main control unit 101 controls the deflection angle of the optical scanner 30 and the light reception timing of the image sensor 51 in accordance with the change in the slit width. Thereby, the time required for photographing using the image sensor 51 can be shortened. Furthermore, the main control unit 101 can reduce the scanning speed of the illumination light irradiation area on the fundus Ef by controlling the slit 22 in the illumination optical system 20 to reduce the slit width of the slit 22 (slit width Sw0 (When changing from slit width Sw1 to slit width Sw1). In this case, the main control unit 101 controls the deflection angle of the optical scanner 30 and the light reception timing of the image sensor 51 in accordance with the change in the slit width. Thereby, the time required for photographing using the image sensor 51 can be increased.

In step S32, the main controller 101 controls the slit 22 in the illumination optical system 20 to increase the slit width of the slit 22, thereby increasing the scanning speed of the illumination light irradiated area of the fundus Ef. As a result, the imaging time using the image sensor 51 can be shortened.

(S33: Flare judgment)
Next, the main control unit 101 causes the flare determination unit 221 to perform flare determination.

The flare determination unit 221 determines whether or not a flare has occurred by analyzing the IR image that began to be acquired in step S2. This makes it possible to determine whether or not a flare has occurred in the IR image after the processing in step S32.

(S34: Flare occurred?)
The main control unit 101 determines whether flare has occurred in the IR image based on the determination result obtained by the flare determination process in step S33.

When it is determined in step S34 that flare has occurred in the IR image (S34: Y), the processing of the ophthalmic device 1 proceeds to step S35. On the other hand, when it is determined that flare has not occurred in the IR image (S34: N), the processing of the ophthalmic device 1 proceeds to step S31.

(S35: Return to shooting conditions before change)
In step S34, when it is determined that a flare occurs in the IR image (S34: Y), the main control unit 101 returns the current shooting conditions to the shooting conditions before the change. In other words, the main control unit 101 returns the current shooting conditions to the shooting conditions immediately before it was determined that no flare occurs in the IR image.

As described above, the shooting time optimization control in step S8 in FIG. 11 is repeated until it is determined that a flare has occurred.

As described above, in step S6, the main control unit 101 executes flare optimization control when it is determined that flare has occurred in the IR image, and executes shooting time optimization control when it is determined that no flare has occurred in the IR image.

In the flare optimization control, the main control unit 101 controls at least one of the first light source 10, the illumination optical system 20, the optical scanner 30, the photographing optical system 40, and the image sensor 51 so that flare does not occur. Change the shooting conditions. When it is determined in step S28 that no flare occurs using the IR image acquired under the imaging conditions changed by the flare optimization control, the image forming unit 210 uses the imaging conditions changed by the flare optimization control. An image of the fundus Ef is formed based on the light reception results captured by the image sensor 51 obtained under the conditions.

In the photographing time optimization control, the main control unit 101 changes the photographing conditions so as to shorten the photographing time of the fundus Ef by controlling at least one of the first light source 10, the illumination optical system 20, the optical scanner 30, the photographing optical system 40, and the image sensor 51. When it is determined in step S34 that a flare has occurred using the IR image acquired under the photographing conditions changed by the photographing time optimization control, the image forming unit 210 returns to the photographing conditions before the change, and forms an image of the fundus Ef based on the light reception results captured by the image sensor 51 acquired under the photographing conditions before the change.

[Action/Effect]
The operation and effects of the ophthalmologic apparatus, its control method, and program according to the embodiment will be described.

An ophthalmic device (1) according to some embodiments includes a first light source (10), an illumination optical system (20), an optical scanner (30), an imaging optical system (40), an acquisition unit (a second light source 11, a half mirror 12, an illumination optical system 20, an optical scanner 30, a projection optical system 35, an imaging optical system 40, an imaging device 50, a control unit 100, and an image forming unit 210), a flare determination unit (221), a control unit (100, a main control unit 101), and an image forming unit (220). The illumination optical system generates slit-shaped illumination light using light from the first light source. The optical scanner deflects the illumination light and guides it to the fundus (Ef) of the subject's eye (E). The imaging optical system guides the return light from the fundus to an image sensor (51) configured to capture the light reception result of the return light of the illumination light corresponding to the irradiation position of the illumination light on the fundus by a rolling shutter method. The acquisition unit acquires a fundus image (IR image) of the subject's eye using light from the second light source (11). The flare determination unit analyzes the fundus image of the subject's eye to determine whether or not a flare has occurred. The control unit executes a photographing time optimization control that changes the photographing conditions so as to shorten the photographing time of the fundus by controlling at least one of the first light source, the illumination optical system, the optical scanner, the photographing optical system, and the image sensor based on the first judgment result obtained by the flare determination unit (the judgment result obtained in step S6). The image forming unit forms an image of the fundus based on the light reception result captured by the image sensor. When it is determined that a flare has occurred based on the second judgment result (the judgment result obtained in step S34) obtained by the flare determination unit using the fundus image acquired by the acquisition unit under the photographing conditions changed by the photographing time optimization control, the control unit returns the photographing conditions to the photographing conditions before the change, and causes the image forming unit to form an image of the fundus based on the light reception result captured by the image sensor under the photographing conditions before the change.

With this configuration, at least one of the first light source, the illumination optical system, the optical scanner, the photographing optical system, and the image sensor is controlled to acquire a fundus image, and when it is determined that flare has occurred in the acquired fundus image, the photographing conditions are restored to those immediately before the change, making it possible to form an image of the test eye using the rolling shutter method in a short photographing time. This makes it possible to acquire a high-quality image of the test eye while suppressing the occurrence of flare, which varies depending on the test eye.

In some embodiments, the illumination optical system can be arranged at a fundus conjugate position that is optically substantially conjugate with the fundus, and includes a slit (22) in which a slit-shaped first opening whose opening shape can be changed is formed. A second aperture (apertures 21A, 21B) is formed between the first light source and the slit, which can be arranged at an iris conjugate position that is optically substantially conjugate with the iris of the eye to be examined, and whose aperture shape can be changed. and an iris diaphragm (21) that has been adjusted, and when it is determined that there is no flare based on the first determination result, the control unit adjusts the aperture shape of at least one of the first aperture and the second aperture. Control the illumination optical system to increase the size.

According to this configuration, since at least one of the slit and the iris diaphragm is controlled, it is possible to increase the amount of illumination light with a simple configuration and control, and it is possible to suppress the occurrence of flare while achieving short shooting times. It becomes possible to photograph the fundus in a short time.

In some embodiments, the photographing optical system can be arranged at an iris conjugate position that is optically substantially conjugate with the iris of the eye to be examined, and a third opening (hole) is formed in which the shape of the opening can be changed. When it is determined that there is no flare based on the first determination result, the control unit controls the photographing optical system so that the size of the aperture shape of the third aperture increases. Control.

According to this configuration, since the photographing aperture is controlled, the amount of return light of the illumination light can be increased with a simple configuration and control, and while suppressing the occurrence of flare, a high quality image of the eye to be examined can be obtained. It becomes possible to obtain images of

In some embodiments, the taking diaphragm couples the optical path of the illumination optics and the optical path of the taking optics arranged in the direction of the optical axis passing through the third aperture, and the imaging diaphragm combines the optical path of the illumination optics with the optical path of the taking optics arranged in the direction of the optical axis passing through the third aperture, and This is a hole mirror (45) configured to guide illumination light reflected by the eye to the fundus of the eye.

According to this configuration, the function of a photographic diaphragm is realized using a hole mirror that connects the optical path of the illumination optical system and the optical path of the photographic optical system, so that the illumination light is irradiated to the fundus by pupil division. At the same time, it becomes possible to simplify the configuration of the optical system and obtain a high-quality image of the eye to be examined.

In some embodiments, when it is determined that flare does not occur based on the first determination result, the control unit controls at least the illumination optical system, the optical scanner, and the image sensor so that the time for photographing the fundus is shortened. Control one.

With this configuration, the illumination optical system, etc. is controlled to shorten the time it takes to capture the fundus, making it possible to obtain high-quality images of the test eye while reliably suppressing the occurrence of flare, which varies depending on the test eye.

In some embodiments, the control unit repeatedly executes the shooting time optimization control until it is determined that a flare has occurred based on the second determination result.

According to this configuration, since the imaging time optimization control is repeatedly executed to shorten the imaging time as much as possible, high-quality images of the eye to be examined can be obtained with simple processing while suppressing the occurrence of flare. It becomes possible to obtain.

In some embodiments, the acquisition unit includes a second light source and acquires a fundus image based on the result of receiving return light from the second light source captured by the image sensor.

This configuration makes it possible to provide an ophthalmic device that is simple in configuration and capable of obtaining high-quality images of the subject's eye while suppressing the occurrence of flare.

In some embodiments, the control unit executes flare optimization control to change the shooting conditions so as to eliminate the occurrence of flare by controlling at least one of the first light source, the illumination optical system, the optical scanner, the shooting optical system, and the image sensor when it is determined based on the first determination result that a flare has occurred, and executes shooting time optimization control when it is determined based on the first determination result that a flare has not occurred.

With this configuration, when it is determined that flare is occurring, it is possible to capture images in a way that suppresses the occurrence of flare, making it possible to obtain higher quality images of the subject's eye.

In some embodiments, the image sensor is a CMOS image sensor.

This configuration makes it possible to obtain high-quality images of the test eye while suppressing the occurrence of flare, which varies depending on the test eye, with a simple configuration and low cost.

A method of controlling an ophthalmological apparatus (1) according to some embodiments includes a first light source (10), an illumination optical system (20), a light scanner (30), a photographing optical system (40), and an acquisition unit. (second light source 11, half mirror 12, illumination optical system 20, optical scanner 30, projection optical system 35, photographing optical system 40, imaging device 50, control section 100, and image forming section 210). This is a control method. The illumination optical system generates slit-shaped illumination light using light from the first light source. The optical scanner deflects the illumination light and guides it to the fundus (Ef) of the eye (E) to be examined. The photographing optical system guides the return light from the fundus to an image sensor (51) configured to capture the result of receiving bright return light corresponding to the illumination light irradiation position on the fundus using a rolling shutter method. The acquisition unit acquires a fundus image of the eye to be examined using light from the second light source (11). The method for controlling an ophthalmological apparatus includes a first flare determination step in which the presence or absence of flare is determined by analyzing a fundus image of the eye to be examined; and a first flare determination step based on the first determination result obtained in the first flare determination step. A control step of executing imaging time optimization control for changing imaging conditions so that the imaging time of the fundus is further shortened by controlling at least one of a light source, an illumination optical system, a light scanner, an imaging optical system, and an image sensor. and an image forming step of forming an image of the fundus based on the light reception result captured by the image sensor, and the control step includes an image forming step of forming an image of the fundus based on the light reception result captured by the image sensor, and the control step includes the step of forming an image of the fundus of the eye based on the light reception result captured by the image sensor. When it is determined that flare has occurred based on the second determination result obtained in the first flare determination step using the fundus image, the photographing conditions are returned to the photographing conditions before the change, and the image forming step is performed. An image of the fundus is formed based on the light reception results captured by the image sensor under the previous imaging conditions.

According to this method, at least one of the first light source, the illumination optical system, the optical scanner, the photographing optical system, and the image sensor is controlled to acquire a fundus image, and when it is determined that flare has occurred in the acquired fundus image, the photographing conditions are restored to those before the most recent change, making it possible to form an image of the test eye using the rolling shutter method in a short photographing time. This makes it possible to acquire a high-quality image of the test eye while suppressing the occurrence of flare, which varies depending on the test eye.

In some embodiments, the illumination optical system includes a slit (22) that can be arranged at a fundus conjugate position that is approximately optically conjugate with the fundus and has a slit-shaped first opening with a changeable opening shape, and an iris diaphragm (21) that can be arranged at an iris conjugate position that is approximately optically conjugate with the iris of the subject's eye between the first light source and the slit and has a second opening (openings 21A, 21B) with a changeable opening shape, and when it is determined based on the first determination result that no flare has occurred, the control step controls the illumination optical system so that the size of the opening shape of at least one of the first opening and the second opening is increased.

According to this method, at least one of the slit and the iris diaphragm is controlled, so that the amount of illumination light can be increased with a simple configuration and control, and it becomes possible to photograph the fundus in a short photographing time while suppressing the occurrence of flare.

In some embodiments, the photographing optical system includes a photographing aperture (hole mirror 45) that can be positioned at an iris conjugate position that is approximately optically conjugate with the iris of the subject's eye and has a third opening (hole portion) whose opening shape is changeable, and when it is determined based on the first judgment result that no flare has occurred, the control step controls the photographing optical system so that the size of the opening shape of the third opening is increased.

By using this method, the imaging aperture is controlled, so the amount of return light from the illumination light can be increased with a simple configuration and control, making it possible to obtain a high-quality image of the test eye while suppressing the occurrence of flare.

In some embodiments, the control step includes controlling at least the illumination optical system, the optical scanner, and the image sensor so that the time required to image the fundus is shortened when it is determined that no flare occurs based on the first determination result. Control one.

This method controls the illumination optical system etc. so that the time it takes to capture the fundus is shortened, making it possible to obtain high-quality images of the subject's eye while reliably suppressing the occurrence of flare, which varies depending on the subject's eye.

In some embodiments, the control step repeatedly executes the imaging time optimization control until it is determined that flare has occurred based on the second determination result.

This method repeatedly performs imaging time optimization control to shorten the imaging time as much as possible, making it possible to obtain high-quality images of the subject's eye with simple processing while suppressing the occurrence of flare.

In some embodiments, the controlling step includes controlling at least one of the first light source, the illumination optical system, the optical scanner, the photographing optical system, and the image sensor when it is determined that flare has occurred based on the first determination result. Execute flare optimization control that changes the photographing conditions so that the occurrence of flare is eliminated by controlling , and execute photographing time optimization control when it is determined that no flare occurs based on the first determination result. .

According to such a method, when it is determined that flare has occurred, it becomes possible to take an image to suppress the occurrence of flare, and it becomes possible to obtain a higher quality image of the eye to be examined. .

In some embodiments, the image sensor is a CMOS image sensor.

This method makes it possible to obtain high-quality images of the test eye while suppressing the occurrence of flare, which varies depending on the test eye, with a simple configuration and low cost.

Some embodiments are programs that cause a computer to execute each step of any of the above-mentioned methods for controlling an ophthalmic device.

According to such a program, at least one of the first light source, the illumination optical system, the optical scanner, the photographing optical system, and the image sensor is controlled to acquire a fundus image, and when it is determined that flare has occurred in the acquired fundus image, the photographing conditions are restored to those before the most recent change, making it possible to form an image of the test eye using the rolling shutter method in a short photographing time. This makes it possible to acquire a high-quality image of the test eye while suppressing the occurrence of flare, which varies depending on the test eye.

The above-described embodiment or its modified examples are merely examples of how to implement this invention. Anyone who wishes to implement this invention may make any modifications, omissions, additions, etc. within the scope of the gist of this invention.

In the above embodiments, the ophthalmologic apparatus has any function usable in the ophthalmology field, such as an axial length measurement function, an intraocular pressure measurement function, an optical coherence tomography (OCT) function, and an ultrasound examination function. You can leave it there. Note that the axial length measurement function is realized by an optical coherence tomography device or the like. In addition, the axial length measurement function projects light onto the eye to be examined and detects the return light from the fundus while adjusting the position of the optical system in the Z direction (anterior-posterior direction) with respect to the eye to be examined. The axial length of the eye may be measured. The intraocular pressure measurement function is realized by a tonometer or the like. The OCT function is realized by optical coherence tomography or the like. The ultrasonic testing function is realized by an ultrasonic diagnostic device or the like. Further, the present invention can also be applied to a device (multifunction device) that has two or more of these functions.

In some embodiments, a program is provided for causing a computer to execute the above-mentioned method for controlling an ophthalmic device. Such a program can be stored in any non-transitory recording medium that is readable by a computer. The recording medium may be an electronic medium that uses magnetism, light, magneto-optical, semiconductors, or the like. Typically, the recording medium is a magnetic tape, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, a solid-state drive, or the like. It is also possible to transmit and receive this program via a network such as the Internet or a LAN.

1 Ophthalmic apparatus 10 Light source 20 Illumination optical system 21 Iris diaphragm 22 Slits 23, 41, 44, 48 Relay lens 30 Optical scanner 35 Projection optical system 40 Photographic optical system 42 Sunspot plate 43 Reflection mirror 45 Hole mirror 46 Objective lens 47 Focusing lens 49 Imaging lens 50 Imaging device 51 Image sensor 100 Control unit 101 Main control unit 102 Storage unit 200 Data processing unit 210 Image forming unit 220 Analysis unit 221 Flare determination unit 222 Fixation micromovement determination unit 223 Light amount determination unit E Eye to be examined Ef Fundus

Claims (12)

a first light source;
a second light source;
an illumination optical system that generates slit-shaped illumination light using the light from the first light source or the light from the second light source ;
an optical scanner that deflects the illumination light and guides it to the fundus of the eye to be examined;
a photographing optical system that guides the return light from the fundus to an image sensor configured to capture the reception result of the return light of the illumination light corresponding to the irradiation position of the illumination light on the fundus in a rolling shutter manner;
an acquisition unit that acquires a fundus image of the eye to be examined based on a reception result of the return light from the second light source captured by the image sensor ;
a flare determination unit that determines whether flare has occurred by analyzing a fundus image of the eye to be examined ;
When it is determined that the flare does not occur based on the first determination result obtained by the flare determination section, at least one of the illumination optical system, the optical scanner, the photographing optical system, and the image sensor is activated. a control unit that executes imaging time optimization control that increases the amount of received light of the return light of the illumination light and changes the imaging conditions so that the imaging time of the fundus is further shortened;
an image forming unit that forms an image of the fundus of the eye based on a result of receiving returned light from the first light source captured by the image sensor;
including;
The control unit determines the flare based on a second determination result obtained by the flare determination unit using the fundus image acquired by the acquisition unit under photography conditions changed by the photography time optimization control. The photographing time optimization control is repeatedly executed until it is determined that flare has occurred, and when it is determined that flare has occurred based on the second determination result, the photographing conditions are changed to the photographing conditions before the change. and causing the image forming unit to form an image of the fundus based on the light reception result captured by the image sensor under the imaging conditions before the change. The illumination optical system includes:
a slit that can be arranged at a fundus conjugate position that is optically substantially conjugate with the fundus and has a slit-shaped first opening whose opening shape is changeable;
an iris diaphragm that can be arranged at an iris conjugate position that is optically substantially conjugate with an iris of the subject's eye between the first light source and the second light source and the slit, and that has a second opening whose opening shape is changeable;
Including,
The ophthalmic apparatus according to claim 1, wherein when it is determined based on the first determination result that no flare is occurring, the control unit controls the illumination optical system so that a size of an opening shape of at least one of the first opening and the second opening is increased. The photographing optical system can be arranged at an iris conjugate position that is optically substantially conjugate with the iris of the eye to be examined, and includes a photographing diaphragm formed with a third aperture whose aperture shape can be changed;
When it is determined that the flare does not occur based on the first determination result, the control unit controls the photographing optical system so that the size of the aperture shape of the third aperture is increased. The ophthalmologic apparatus according to claim 1 or 2, wherein: The photographic diaphragm couples the optical path of the illumination optical system with the optical path of the photographic optical system disposed in the direction of the optical axis passing through the third opening, and also prevents reflection in the peripheral area of the third opening. The ophthalmologic apparatus according to claim 3, wherein the ophthalmologic apparatus is a hole mirror configured to guide the illuminated illumination light to the fundus of the eye. The control unit controls at least one of the illumination optical system, the optical scanner, the photographing optical system, and the image sensor when it is determined that the flare has occurred based on the first determination result . thereby executing flare optimization control for changing the imaging conditions so that the flare does not occur, and executing the imaging time optimization control when it is determined that the flare does not occur based on the first determination result. The ophthalmological device according to any one of claims 1 to 4, characterized in that: The ophthalmologic apparatus according to any one of claims 1 to 5 , wherein the image sensor is a CMOS image sensor. a first light source;
a second light source;
an illumination optical system that generates slit-shaped illumination light using the light from the first light source or the light from the second light source ;
an optical scanner that deflects the illumination light and guides it to the fundus of the eye to be examined;
a photographing optical system that guides the return light from the fundus to an image sensor configured to capture the reception result of the return light of the illumination light corresponding to the irradiation position of the illumination light on the fundus in a rolling shutter manner;
an acquisition unit that acquires a fundus image of the eye to be examined based on a reception result of the return light from the second light source captured by the image sensor ;
A method for controlling an ophthalmological device, the method comprising:
a first flare determination step of determining the presence or absence of flare by analyzing a fundus image of the eye to be examined;
When it is determined that the flare does not occur based on the first determination result obtained in the first flare determination step, at least one of the illumination optical system, the optical scanner, the photographing optical system, and the image sensor a control step of executing imaging time optimization control of increasing the amount of received light of the return light of the illumination light and changing the imaging conditions so that the imaging time of the fundus is further shortened;
an image forming step of forming an image of the fundus of the eye based on a reception result of the return light from the first light source captured by the image sensor;
including;
The control step is based on the second determination result obtained in the first flare determination step using the fundus image acquired by the acquisition unit under the imaging conditions changed by the imaging time optimization control. The photographing time optimization control is repeatedly executed until it is determined that the flare has occurred, and when it is determined that the flare has occurred based on the second determination result , the photographing conditions are changed to the photographing time before the change. return to the condition,
In the method for controlling an ophthalmological apparatus, the image forming step forms an image of the fundus based on the light reception result captured by the image sensor under the imaging conditions before the change. The illumination optical system includes:
a slit in which a slit-shaped first opening is formed, which can be placed at a position optically substantially conjugate with the fundus, and whose opening shape can be changed;
A second aperture is formed between the first light source and the second light source and the slit, the second aperture being disposed at an iris conjugate position that is optically substantially conjugate with the iris of the eye to be examined, and having a changeable aperture shape. iris diaphragm and
including;
When it is determined that the flare does not occur based on the first determination result, in the control step, the size of the opening shape of at least one of the first opening and the second opening is increased. The method for controlling an ophthalmological apparatus according to claim 7, further comprising controlling an illumination optical system. The photographing optical system can be arranged at an iris conjugate position that is optically substantially conjugate with the iris of the eye to be examined, and includes a photographing diaphragm formed with a third aperture whose aperture shape can be changed;
When it is determined that the flare does not occur based on the first determination result, the control step controls the photographing optical system so that the size of the aperture shape of the third aperture is increased. The method for controlling an ophthalmological apparatus according to claim 7 or 8 . The control step controls at least one of the illumination optical system, the optical scanner, the photographing optical system, and the image sensor when it is determined that the flare has occurred based on the first determination result. thereby executing flare optimization control for changing the imaging conditions so that the flare does not occur, and executing the imaging time optimization control when it is determined that the flare does not occur based on the first determination result. The method for controlling an ophthalmological apparatus according to any one of claims 7 to 9, characterized in that: The method for controlling an ophthalmological apparatus according to any one of claims 7 to 10 , wherein the image sensor is a CMOS image sensor. A program for causing a computer to execute each step of the method for controlling an ophthalmological apparatus according to any one of claims 7 to 11 .

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