Ophthalmic device, control method thereof, and recording medium

Abstract

The present invention discloses an ophthalmic device, comprising an illumination optical system, an optical scanner, a photographing optical system, a control unit, and an image forming unit. The illumination optical system generates slit-shaped illumination light. The optical scanner deflects the illumination light and guides the illumination light to the fundus of the eye to be examined. The photographing optical system guides the return light of the illumination light from the fundus to an image sensor. The control unit controls the optical scanner. The image forming unit forms an image of the fundus based on the light reception result obtained in the photographing object area on the light receiving surface of the image sensor. The image sensor is configured to obtain the light reception result in the opening area of the light receiving surface corresponding to the illumination area of the fundus by the illumination light moving in a predetermined scanning direction by the optical scanner in a rolling shutter manner. The control unit controls the optical scanner in such a manner that the irradiation time of the return light on each of the multiple light receiving elements in the photographing object area is approximately equal.

Description

Technical Field

[0001] The present invention relates to an ophthalmologic device, a control method thereof, and a recording medium. Background Art

[0002] In recent years, ophthalmic devices have been used for screening examinations. Such ophthalmic devices are also expected to be used for self-examination and are expected to be further miniaturized and lightweight.

[0003] For example, Patent Documents 1 to 4 disclose ophthalmic devices that illuminate the subject's eye with a pattern and receive the resulting return light via an image sensor using a rolling shutter method. By adjusting the illumination pattern and the timing of light reception by the image sensor, these ophthalmic devices can acquire an image of the subject's eye with a simple configuration.

[0004] For example, patent document 4 discloses a line scanning microscope, which includes a scanning unit that controls the scanning trajectory in a manner that satisfies time synchronization and spatial synchronization between the illumination side and the light receiving side within the entire area of the field of view of the sensor unit and has an acceleration part and a deceleration part outside the field of view of the sensor unit.

[0005] Patent Document 1: U.S. Patent No. 7,831,106

[0006] Patent Document 2: U.S. Patent No. 8,237,835

[0007] Patent Document 3: U.S. Patent No. 7,335,898

[0008] Patent Document 4: Japanese Patent No. 5897563 Summary of the Invention

[0009] However, conventional methods have the problem that the imaging time cannot be shortened, and even if the imaging time can be shortened, the illumination time within the imaging target area of the image sensor fluctuates.

[0010] If the shooting time is long, eye movement may occur during shooting, which may cause troublesome reshooting. If the lighting time in the shooting object area fluctuates, the obtained image may produce bright spots, resulting in degraded image quality.

[0011] The present invention has been made in view of the above circumstances, and one of its objects is to provide a new technology for obtaining a high-quality image of an eye to be inspected in a short imaging time.

[0012] A first method in some embodiments relates to an ophthalmic device, comprising: an illumination optical system that generates slit-shaped illumination light; a light scanner that deflects the illumination light and guides the illumination light to the fundus of an eye to be inspected; a photographing optical system that guides return light of the illumination light from the fundus to an image sensor; a control unit that controls the light scanner; and an image forming unit that forms an image of the fundus based on a light reception result obtained in a photographing object area in a light receiving surface of the image sensor, the image sensor being configured to obtain light reception results in an opening area of the light receiving surface corresponding to the illumination area of the illumination light in the fundus moved in a predetermined scanning direction by the light scanner in a rolling shutter manner, the control unit controlling the light scanner in such a manner that the irradiation time of the return light on each of a plurality of light receiving elements in the photographing object area is approximately equal.

[0013] The second embodiment of some embodiments is based on the first embodiment, wherein, in the image sensor, the group of light-receiving elements arranged in the row direction orthogonal to the shift direction of the opening area shifted corresponding to the illumination area includes a plurality of light-receiving elements arranged in the column direction, the width of the irradiation range corresponding to the illumination area in the light-receiving surface in the shift direction has a width equivalent to more than two rows, and the control unit controls the light scanner in such a manner that the irradiation range is shifted in the shift direction from the outside of the photographic object area by a predetermined number of rows.

[0014] According to a third aspect of some embodiments of the present invention, according to the second aspect, the control unit controls the optical scanner so that the irradiation range is shifted from the outside of the imaging target area by a width corresponding to at least a number of lines.

[0015] A fourth embodiment of some embodiments is according to the second embodiment or the third embodiment, wherein the control unit controls the light scanner in such a manner that the irradiation range is shifted from the outside of the photographing object area by the width in the shift direction of the area on the light receiving surface corresponding to the illumination area.

[0016] A fifth embodiment of some embodiments is according to the second embodiment or the third embodiment, wherein the control unit controls the light scanner in such a manner that the irradiation range is shifted from the outside of the photographing object area to a predetermined width that is greater than the width in the shift direction of the area corresponding to the illumination area in the light receiving surface.

[0017] A sixth aspect of some embodiments is according to the fifth aspect, wherein the predetermined width is the sum of a width in the shift direction of an area of the light-receiving surface corresponding to the illumination area and a width corresponding to a number of rows corresponding to an unstable operating area of the optical scanner.

[0018] According to a seventh aspect of some embodiments, according to any one of the first to sixth aspects, the image sensor is a CMOS image sensor.

[0019] An eighth aspect of some embodiments relates to a method for controlling an ophthalmic device, the ophthalmic device comprising: an illumination optical system that generates slit-shaped illumination light; a light scanner that deflects the illumination light and guides it toward a fundus of an eye to be examined; a photographing optical system that guides return light from the fundus to an image sensor, the image sensor configured to acquire light reception results in an opening area of a light receiving surface corresponding to an area illuminated by the illumination light in the fundus, which is moved in a predetermined scanning direction by the light scanner, using a rolling shutter method; and a control unit that controls the light scanner. The method comprises: a control step of controlling the light scanner so that the return light irradiates each of a plurality of light receiving elements in an imaging target area on the light receiving surface of the image sensor for substantially equal periods of time; and an image forming step of forming an image of the fundus based on the light reception results acquired in the imaging target area.

[0020] A ninth embodiment of some embodiments is based on the eighth embodiment, wherein, in the image sensor, the group of light-receiving elements arranged in a row direction orthogonal to the shift direction of the opening area shifted corresponding to the illumination area includes a plurality of light-receiving elements arranged in a column direction, the width of the irradiation range corresponding to the illumination area in the light-receiving surface in the shift direction has a width equivalent to more than two rows, and in the control step, the light scanner is controlled in such a manner that the irradiation range is shifted in the shift direction by a predetermined number of rows from the outside of the photographic object area.

[0021] According to a tenth aspect of some embodiments, according to the ninth aspect, the light scanner is controlled in the controlling step so as to shift the irradiation range from the outside of the imaging target area by a width corresponding to at least a number of lines.

[0022] The eleventh embodiment of some embodiments is according to the ninth embodiment or the tenth embodiment, wherein, in the control step, the light scanner is controlled in such a manner that the irradiation range is shifted from the outside of the photographing object area by the width in the shift direction of the area in the light receiving surface corresponding to the illumination area.

[0023] The twelfth embodiment of some embodiments is according to the ninth embodiment or the tenth embodiment, wherein, in the control step, the light scanner is controlled in such a manner that the irradiation range is shifted from the outside of the photographing object area to a predetermined width that is larger than the width in the shift direction of the area in the light receiving surface corresponding to the illumination area.

[0024] A thirteenth embodiment of some embodiments is according to the twelfth embodiment, wherein the predetermined width is the sum of a width in the shift direction of an area of the light-receiving surface corresponding to the illumination area and a width corresponding to a number of rows corresponding to an unstable operating area of the light scanner.

[0025] A fourteenth aspect of some embodiments according to any one of the eighth to thirteenth aspects, wherein the image sensor is a CMOS image sensor.

[0026] A fifteenth aspect of some embodiments relates to a program causing a computer to execute each step of the method for controlling an ophthalmologic apparatus according to any one of the eighth to fourteenth aspects.

[0027] Furthermore, the structures according to the above-described plurality of aspects can be arbitrarily combined.

[0028] According to the present invention, a new technology for obtaining a high-quality image of a subject's eye in a short imaging time can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to an embodiment.

[0030] Figure 2 : is a schematic diagram showing a configuration example of a control system of an ophthalmologic apparatus according to an embodiment.

[0031] Figure 3 Schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to an embodiment.

[0032] Figure 4 It is a diagram for explaining the operation of the ophthalmologic apparatus according to the embodiment.

[0033] Figure 5 It is a diagram for explaining the operation of the ophthalmologic apparatus according to the embodiment.

[0034] Figure 6 It is a diagram for explaining the operation of the ophthalmologic apparatus according to the embodiment.

[0035] Figure 7 It is a diagram for explaining the operation of the ophthalmologic apparatus according to the embodiment.

[0036] Figure 8 It is a diagram for explaining the operation of the ophthalmologic apparatus according to the embodiment.

[0037] Figure 9A It is a diagram for explaining the operation of the ophthalmologic apparatus according to the embodiment.

[0038] Figure 9B It is a diagram for explaining the operation of the ophthalmologic apparatus according to the embodiment.

[0039] Figure 9C It is an explanatory diagram of the operation of an ophthalmologic apparatus according to a comparative example of the embodiment.

[0040] Figure 10 It is an explanatory diagram of the operation of the ophthalmologic apparatus according to a modified example of the embodiment.

[0041] Figure 11 It is an explanatory diagram of the operation of the ophthalmologic apparatus according to a modified example of the embodiment. DETAILED DESCRIPTION

[0042] An example of an embodiment of an ophthalmologic apparatus, a control method thereof, and a program according to the present invention will be described in detail with reference to the accompanying drawings. In addition, the contents of the following embodiments may be appropriately cited from the documents described in this specification.

[0043] According to the ophthalmic device of the embodiment, the irradiation position (irradiation area, irradiation range) of the slit-shaped illumination light is moved while illuminating a predetermined part of the eye to be inspected, and an image sensor with a one-dimensional or two-dimensional array of light-receiving elements is used to receive the return light from the predetermined part. The light-receiving result of the return light is read from the light-receiving element at the light-receiving position of the return light corresponding to the irradiation position of the illumination light in synchronization with the movement timing of the irradiation position of the illumination light. In some embodiments, the predetermined part is the anterior eye or the posterior eye. The anterior eye includes the cornea, iris, lens, ciliary body, ciliary zonules, etc. The posterior eye includes the vitreous body, the fundus or its vicinity (retina, choroid, sclera, etc.), etc.

[0044] The control method of the ophthalmologic apparatus according to the embodiment includes one or more steps for realizing processing executed by a processor (computer) in the ophthalmologic apparatus according to the embodiment. The program according to the embodiment causes the processor to execute each step of the control method of the ophthalmologic apparatus according to the embodiment.

[0045] In this specification, the term "processor" refers to circuits such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), and a programmable logic device (e.g., a Simple Programmable Logic Device (SPLD), a Complex Programmable Logic Device (CPLD), or a Field Programmable Gate Array (FPGA)). The processor implements functions according to the embodiments by, for example, reading and executing programs stored in a storage circuit or storage device.

[0046] Hereinafter, a case where an image of the fundus of the eye to be inspected is obtained by the ophthalmologic apparatus according to the embodiment will be mainly described.

[0047] [Optical system structure]

[0048] Figures 1 to 3 A schematic diagram showing a configuration example of an ophthalmologic apparatus according to an embodiment. Figure 1 A configuration example of the optical system of the ophthalmologic apparatus 1 according to the embodiment is shown. Figure 2 A block diagram showing a configuration example of a control system (processing system) of the ophthalmologic apparatus 1 according to the embodiment. Figure 3 Schematically shows the Figure 1 An example of the structure of the iris diaphragm 21. Figures 1 to 3 In the drawings, the same parts are denoted by the same reference numerals and descriptions thereof are appropriately omitted.

[0049] The ophthalmic apparatus 1 includes a light source 10, an illumination optical system 20, a light scanner 30, a projection optical system 35, a photographic optical system 40, and an imaging device 50. In some embodiments, the illumination optical system 20 includes at least one of the light source 10, the light scanner 30, and the projection optical system 35. In some embodiments, the photographic optical system 40 includes the imaging device 50. In some embodiments, the projection optical system 35 or the photographic optical system 40 includes the light scanner 30.

[0050] (Light source 10)

[0051] The light source 10 includes a visible light source that generates light in the visible region. For example, the light source 10 generates light having a central wavelength in the wavelength range of 420 nm to 700 nm. Such a 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 light source 10 includes a white light source or a light source that can output light of each color component of RGB. In some embodiments, the light source 10 includes a light source that can switch and output light in the infrared region or light in the visible region. The light source 10 is arranged at a position that is optically non-conjugate with the fundus Ef and the iris, respectively.

[0052] (Illumination Optical System 20)

[0053] The illumination optical system 20 generates slit-shaped illumination light using the light from the light source 10 , and guides the generated illumination light to the optical scanner 30 .

[0054] The illumination optical system 20 includes an iris diaphragm 21, a slit 22, and a relay lens 23. Light from the light source 10 passes through an opening formed in the iris diaphragm 21, passes through an opening formed in the slit 22, and then passes through the relay lens 23. The relay lens 23 includes one or more lenses. The light passing through the relay lens 23 is guided to the optical scanner 30.

[0055] (iris aperture 21)

[0056] The iris diaphragm 21 (specifically, the opening described later) can be arranged at a position that is optically substantially conjugate with the iris (pupil) of the eye E. The iris diaphragm 21 is formed with one or more openings at positions away from the optical axis O. For example, Figure 3 As shown in FIG. 1 , the iris diaphragm 21 is provided with openings 21A and 21B having a predetermined thickness along a circumferential direction centered on the optical axis O. The openings formed in the iris diaphragm 21 limit the incident position (incident shape) of the illumination light in the iris of the subject's eye E. For example, Figure 3 As shown, by forming the openings 21A and 21B, when the pupil center of the subject's eye E is arranged on the optical axis O, illumination light can be incident on the eye from a position offset from the pupil center (specifically, a position point-symmetrical about the pupil center).

[0057] Furthermore, by changing the relative position between the light source 10 and the opening formed in the iris diaphragm 21 , the light intensity distribution of light passing through the opening formed in the iris diaphragm 21 can be changed.

[0058] (Fissure 22)

[0059] The slit 22 (specifically, the opening described later) can be arranged at a position that is substantially optically conjugate with the fundus Ef of the eye E to be inspected. For example, the slit 22 has an opening formed in a direction corresponding to the line direction (row direction) read from the image sensor 51 described later using a rolling shutter method. The opening formed in the slit 22 limits the illumination pattern of the fundus Ef of the eye E to be inspected with illumination light.

[0060] The slit 22 is movable in the direction of the optical axis of the illumination optical system 20 by a moving mechanism (moving mechanism 22D, described later). The moving mechanism is controlled by the control unit 100, described later, to move the slit 22 in the direction of the optical axis. For example, the control unit 100 controls the moving mechanism based on the state of the eye E. Thus, the position of the slit 22 can be moved according to the state of the eye E (specifically, the diopter and the shape of the fundus Ef).

[0061] In some embodiments, the slit 22 is configured to change at least one of the position and shape of the opening without moving in the optical axis direction according to the state of the eye E. The function of the slit 22 is realized by, for example, a liquid crystal shutter.

[0062] The light from the light source 10 that has passed through the opening formed in the iris diaphragm 21 is output as slit-shaped illumination light 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.

[0063] (Optical Scanner 30)

[0064] The optical scanner 30 is positioned at a position that is substantially optically conjugate with the iris of the eye E to be inspected. The optical scanner 30 deflects the slit-shaped illumination light (the slit-shaped light that has passed through the opening formed in the slit 22) that has passed 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 eye E or its vicinity as the scanning center position, and then guides the deflected light to the projection optical system 35. The optical scanner 30 is capable of one-dimensional or two-dimensional deflection of the illumination light.

[0065] When performing one-dimensional deflection, the optical scanner 30 includes a galvano scanner that deflects the illumination light within a predetermined deflection angle range based on a predetermined deflection direction. When performing 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 that the illumination light's irradiation position shifts 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 that the illumination light's irradiation position shifts in a vertical direction perpendicular to the optical axis of the illumination optical system 20. Scanning methods for shifting the illumination light's irradiation position using the optical scanner 30 include, for example, horizontal scanning, vertical scanning, cross scanning, radial scanning, circular scanning, concentric scanning, and spiral scanning.

[0066] (Projection optical system 35)

[0067] The projection optical system 35 guides the illumination light deflected by the optical scanner 30 to the fundus Ef of the eye to be inspected E. In the embodiment, the projection optical system 35 guides the illumination light deflected by the optical scanner 30 to the fundus Ef via an optical path coupled with the optical path of the imaging optical system 40 by an aperture mirror 45 as an optical path coupling member described later.

[0068] The projection optical system 35 includes a relay lens 41, a black spot plate 42, a reflection mirror 43, and a relay lens 44. Each of the relay lenses 41 and 44 includes one or more lenses.

[0069] (Black dot plate 42)

[0070] The black spot plate 42 is disposed at a position optically substantially conjugate with the lens surface of the objective lens 46 or its vicinity. This prevents the reflected light from the lens surface of the objective lens 46 from being guided to the light source 10 (illumination optical system 20).

[0071] In the projection optical system 35 , the illumination light deflected by the optical scanner 30 passes through the relay lens 41 , passes through the black dot plate 42 , and is reflected toward the aperture mirror 45 by the reflection mirror 43 .

[0072] (Photographic Optical System 40)

[0073] The photographing optical system 40 guides the illumination light guided by the projection optical system 35 to the fundus Ef of the eye to be inspected E, and guides the return light of the illumination light from the fundus Ef to the imaging device 50 .

[0074] The imaging optical system 40 couples the optical path of the illumination light from the projection optical system 35 and the optical path of the return light from the fundus Ef. By using the aperture mirror 45 as an optical path coupling member for coupling these optical paths, the illumination light and its return light can be pupil-divided.

[0075] The photographing optical system 40 includes an aperture lens 45, an objective lens 46, a focus lens 47, a relay lens 48, and an imaging lens 49. Each of the relay lenses 48 includes one or more lenses.

[0076] (Aperture Mirror 45)

[0077] The aperture mirror 45 has an aperture portion arranged along the optical axis of the imaging optical system 40. The aperture mirror 45 is arranged at a position substantially optically conjugate with the iris of the eye E. The aperture mirror 45 reflects the illumination light from the projection optical system 35 toward the objective lens 46 in a region surrounding the aperture portion.

[0078] (Focusing lens 47)

[0079] The focus lens 47 is movable in the optical axis direction of the imaging optical system 40 by a moving mechanism (not shown). The moving mechanism is controlled by the control unit 100, which will be described later, to move the focus lens 47 in the optical axis direction. Thus, depending on the state of the eye E to be inspected, the return light of the illumination light that has passed through the aperture of the aperture mirror 45 can be imaged on the light-receiving surface of the image sensor 51 of the imaging device 50.

[0080] In this imaging 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 aperture portion formed in the aperture mirror 45. The illumination light reflected in the peripheral area of the aperture mirror 45 is refracted by the objective lens 46, passes through the pupil of the eye E to be inspected, enters the eye, and illuminates the fundus Ef of the eye E to be inspected.

[0081] Return light of the illumination light from the fundus Ef is refracted by the objective lens 46 , passes through the aperture of the aperture mirror 45 , passes through the focus lens 47 , passes through the relay lens 48 , and is imaged on the light receiving surface of the image sensor 51 of the imaging device 50 by the imaging lens 49 .

[0082] (Camera 50)

[0083] 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 by the photographing optical system 40 . The imaging device 50 is controlled by a control unit 100 described later and can output a result of receiving the return light.

[0084] (Image sensor 51)

[0085] 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 arranged at a position that is substantially optically conjugate with the fundus oculi Ef.

[0086] The light reception results from the image sensor 51 are acquired and read using a rolling shutter method. In some embodiments, the control unit 100, described later, controls the reading of the light reception results by controlling the image sensor 51. In some embodiments, the image sensor 51 can automatically output the light reception results corresponding to a predetermined row, along with information indicating the light reception position.

[0087] This image sensor 51 comprises a CMOS image sensor. In this case, the image sensor 51 comprises a plurality of pixels (light-receiving elements) arranged in the row direction, which include a plurality of pixels arranged in the column direction. Specifically, the image sensor 51 comprises a plurality of pixels arranged in a two-dimensional manner, a plurality of vertical signal lines, and a plurality of horizontal signal lines. Each pixel comprises a photodiode (light-receiving element) and a capacitor. A plurality of vertical signal lines are provided in each pixel group 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 that has accumulated charge corresponding to the result of light reception. The horizontal signal lines are selectively electrically connected to the plurality of vertical signal lines. Each pixel accumulates charge corresponding to the result of light reception by the return light, and the accumulated charge is sequentially read for each pixel group in the row direction, for example. For example, a voltage corresponding to the charge accumulated in each pixel is supplied to the vertical signal line for each row in the row direction. The plurality of vertical signal lines are selectively electrically connected to the horizontal signal lines. By sequentially performing a read operation in the vertical direction for each row in the row direction, the result of light reception for the plurality of pixels arranged in a two-dimensional manner can be read.

[0088] By acquiring (reading) the result of receiving the return light using a rolling shutter method for the image sensor 51, a light-receiving image corresponding to a desired virtual aperture shape extending in the row direction is obtained. This type of control is disclosed in, for example, US Pat. No. 8,237,835.

[0089] Figure 4 An operation explanatory diagram of the ophthalmologic apparatus 1 according to the embodiment is shown. Figure 4 The irradiation range IP of the slit-shaped illumination light irradiated to the fundus Ef and the virtual aperture range OP in the light receiving surface SR of the image sensor 51 are schematically shown.

[0090] For example, the control unit 100, which will be described later, uses the optical scanner 30 to deflect the slit-shaped illumination light formed by the illumination optical system 20. As a result, the irradiation range IP of the slit-shaped illumination light in the fundus Ef is sequentially moved (displaced) in a direction (e.g., vertical direction) orthogonal to the slit direction (e.g., row direction, horizontal direction).

[0091] On the light-receiving surface SR of the image sensor 51, for example, the control unit 100, described later, changes the pixels targeted for acquisition on a row-by-row basis, thereby setting a virtual aperture range OP. Desirably, the aperture range OP is the light-receiving range IP' of the return light of the illumination light on the light-receiving surface SR, or a range wider than the light-receiving range IP'. For example, the control unit 100, described later, controls the movement of the aperture range OP in synchronization with the movement control of the illumination light irradiation range IP. This allows for the acquisition of high-quality images of the fundus Ef with high contrast, without being affected by unwanted scattered light, using a simple configuration.

[0092] Figure 5 as well as Figure 6 An example of control timing for the rolling shutter method of the image sensor 51 is schematically shown. Figure 5 An example of the timing of reading control for the image sensor 51 is shown. Figure 6 is Figure 5 The diagram is a diagram showing the movement control timing of the illumination light irradiation range IP (light receiving range IP') superimposed on the reading control timing of the illumination light. Figure 5 as well as Figure 6 In FIG, the horizontal axis represents the number of rows of the image sensor 51 and the vertical axis represents time.

[0093] In addition, Figure 5 as well as Figure 6 In the description, for the sake of convenience, the number of rows of the image sensor 51 is described as 1920, but the structure according to the embodiment is not limited to the number of rows. Figure 6 In the figure, for the sake of convenience, the slit width (width in the row direction) of the slit-shaped illumination light is set to be equivalent to 40 rows.

[0094] The row-direction reading control includes reset control, exposure control, charge transfer control, and output control. Reset control is a control that initializes the amount of charge accumulated in the pixels in the row direction. Exposure control is a control that irradiates light to the photodiode and accumulates charge corresponding to the amount of light received in the capacitor. Charge transfer control is a control that transfers the amount of charge accumulated in the pixel to the vertical signal line. Output control is a control that outputs the amount of charge accumulated in multiple vertical signal lines via the horizontal signal line. That is, as Figure 7 As shown, the reading time T of the charge amount accumulated in the pixels in the row direction is the sum of the reset control required time Tr, the exposure control required time (exposure time) Te, the charge transfer control required time Tc, and the output control required time Tout.

[0095] exist Figure 5 By shifting the reading (acquisition) start timing (the start timing of time Tc) in units of rows, the light reception results (charge amounts) accumulated in the pixels within the desired range in the image sensor 51 are acquired. Figure 7 When the pixel range shown corresponds to an image corresponding to one frame, the frame rate FR is uniquely determined.

[0096] In this embodiment, the irradiation position of the fundus Ef by illumination light having a slit width corresponding to a number of rows is sequentially shifted in a direction corresponding to the column direction in the fundus Ef. When the width of the irradiation area IP' (the area corresponding to the illuminated area in the fundus Ef) on the light-receiving surface of the image sensor 51 in the shift direction is equal to two or more rows, the control unit 100, described later, controls the optical scanner 30 so that the aperture range OP (aperture area) is shifted in the shift direction by a predetermined number of rows.

[0097] For example, Figure 6 As shown, the illumination light's irradiation position on the fundus Ef is shifted row-by-row in a direction corresponding to the column direction at predetermined shift times Δt. The shift time Δt is obtained by dividing the exposure time Te of the pixels in the image sensor 51 by the slit width of the illumination light (for example, the number of rows of slit width = 40) (Δt = Te / 40). In synchronization with the shift timing of this illumination position, the start timing of reading each row of pixels is delayed by the shift time Δt per row. This allows for the acquisition of high-contrast, high-quality images of the fundus Ef in a short time with simple control.

[0098] In some embodiments, the image sensor 51 is composed of more than one line sensor.

[0099] However, in Figure 6 In the illustrated method, the irradiation time of the return light of the illumination light fluctuates across the entire area of the light-receiving surface of the image sensor 51. Specifically, the irradiation time of the return light of the illumination light differs between the pixel group at the beginning of the shift direction (pixels in the row direction between rows 1 to 39) and the pixel group at the end of the shift direction (pixels in the row direction between rows 1881 to 1920) of the illumination light irradiation area relative to the remaining pixel groups.

[0100] Therefore, in the embodiment, the control unit 100 described later desirably controls the optical scanner 30 so that the irradiation time of the return light for each of the plurality of pixels (light receiving elements) in the imaging target area on the light receiving surface of the image sensor 51 is substantially equal.

[0101] Figure 7 An operation explanatory diagram of the ophthalmologic apparatus 1 according to the embodiment is shown. Figure 7 The irradiation range on the light receiving surface of the image sensor 51 is schematically shown.

[0102] For example, Figure 7As shown in FIG. 1 , when setting a photographic target region SR′ in the area of the light receiving surface SR of the image sensor 51 and obtaining an image of the fundus Ef using the light reception results of the pixels in the photographic target region SR′, the irradiation range IP′ is shifted from the outside of the photographic target region SR′. That is, the control unit 100 described later shifts the irradiation range IP′ from the outside of the photographic target region SR′ as shown in FIG. Figure 6 The optical scanner 30 is controlled so as to be shifted as shown in FIG. This reduces fluctuation (variation) in the irradiation time of the return light of the illumination light to the plurality of pixels in the imaging target region SR′.

[0103] In some embodiments, the control unit 100 described later makes the irradiation range IP' extend from the outside of the photographic object area SR' to the outside of the photographic object area SR'. Figure 6 As shown in FIG. 1 , the optical scanner 30 is controlled in such a manner that the width is shifted by at least one line. Figure 6 Compared with the method shown in the figure, it is possible to reduce fluctuations in the irradiation time of the return light of the illumination light to the pixel group in the imaging target region SR′.

[0104] In some embodiments, the control unit 100 described later makes the irradiation range IP' extend from the outside of the photographic object area SR' to the outside of the photographic object area SR'. Figure 6 As shown, the optical scanner 30 is controlled so as to be displaced by an amount corresponding to the width in the displacement direction of the irradiation range IP′ on the light receiving surface of the image sensor 51 .

[0105] Figure 8 An example of the control timing of the rolling shutter method for the imaging target area SR' on the light receiving surface SR of the image sensor 51 is schematically shown. Figure 8 In, with Figure 6 or Figure 7 The same parts are given the same reference numerals and the description thereof is omitted as appropriate. Figure 8 In the figure, the slit width (width in the row direction) of the slit-shaped illumination light is set to be equivalent to 40 rows.

[0106] like Figure 8 As shown, the control unit 100 described later makes the irradiation range IP' from the outside of the photographic object area SR' as shown in FIG. Figure 6 As shown, the optical scanner 30 is controlled so as to shift the width (a width corresponding to 40 lines) of the irradiation range IP' on the light-receiving surface of the image sensor 51 in the shift direction. This makes it possible to make the fluctuation of the irradiation time of the return light of the illumination light on all pixel groups within the imaging target region SR' substantially equal.

[0107] [Structure of the control system]

[0108] like Figure 2As shown, the control system of the ophthalmologic apparatus 1 is configured around the control unit 100. In addition, at least a part of the structure of the control system may be included in the ophthalmologic apparatus 1.

[0109] (Control Unit 100)

[0110] The control unit 100 controls each unit of the ophthalmologic apparatus 1. The control unit 100 includes a main control unit 101 and a storage unit 102. The main control unit 101 includes a processor and executes processing according to a program stored in the storage unit 102 to control each unit of the ophthalmologic apparatus 1.

[0111] (Main control unit 101)

[0112] The main control unit 101 controls the light source 10 , the moving mechanism 10D, the illumination optical system 20 , the optical scanner 30 , the imaging optical system 40 , the imaging device 50 , and the data processing unit 200 .

[0113] Control of the light source 10 includes turning on and off the light source (or switching of the wavelength range of light) and control of changing the light amount of the light source.

[0114] The moving mechanism 10D uses a known mechanism to change at least one of the position and orientation of the light source 10. The main control unit 101 can change at least one of the relative position and orientation of the light source 10 with respect to the iris diaphragm 21 and the slit 22.

[0115] Control of the illumination optical system 20 includes control of the moving mechanism 22D. The moving mechanism 22D moves the slit 22 in the optical axis direction of the illumination optical system 20. The main control unit 101 controls the moving mechanism 22D according to the state of the eye E to be inspected, thereby configuring the slit 22 at a position corresponding to the state of the eye E to be inspected. The state of the eye E to be inspected includes the shape of the fundus Ef, the diopter, the axial length of the eye, etc. The diopter can be obtained by a known eye refractive power measuring device such as that disclosed in Japanese Patent Application Laid-Open No. 61-293430 or Japanese Patent Application Laid-Open No. 2010-259495. The axial length of the eye can be obtained from a measurement value obtained by a known axial length measuring device or an optical coherence tomography.

[0116] For example, first control information that preliminarily associates the position of the slit 22 on the optical axis of the illumination optical system 20 with the diopter 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 diopter, and controls the moving mechanism 22D so that the slit 22 is positioned at the specified position.

[0117] Here, the light quantity distribution of light passing through the opening formed in the slit 22 changes as the slit 22 moves. At this time, as described above, the main control unit 101 can change the position and direction of the light source 10 by controlling the moving mechanism 10D.

[0118] 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, the scanning range (scan start position and scan end position) can be controlled. By controlling the change rate of the deflection surface angle, the scanning speed can be controlled.

[0119] Control of the photographic optical system 40 includes control of the moving mechanism 47D. The moving mechanism 47D moves the focus lens 47 in the optical axis direction of the photographic optical system 40. The main control unit 101 can control the moving mechanism 47D based on the analysis results of the image obtained by the image sensor 51. The main control unit 101 can also control the moving mechanism 47D based on the user's operation using the operation unit 110 described later.

[0120] Control of the imaging device 50 includes control of the image sensor 51. This control includes control for reading light-receiving results using a rolling shutter method (for example, setting the light-receiving size corresponding to the size of the illumination pattern). Furthermore, control of the image sensor 51 includes reset control, exposure control, charge transfer control, and output control. The reset control time Tr, exposure control time (exposure time) Te, charge transfer control time Tc, and output control time Tout can be changed.

[0121] The control of the data processing unit 200 includes various image processing and analysis processes for the light reception results obtained from the image sensor 51. Image processing includes noise removal processing for the light reception results and brightness correction processing to facilitate identification of predetermined locations drawn in the light reception image based on the light reception results. Analysis processing includes specific processing for determining the focus state, etc.

[0122] The data processing unit 200 can form a light-receiving image corresponding to any aperture range based on the light-receiving results read from the image sensor 51 using a rolling shutter method. As an image forming unit, the data processing unit 200 can sequentially form light-receiving images corresponding to the aperture range and form an image of the subject's eye E from the multiple light-receiving images formed.

[0123] The data processing unit 200 includes a processor, and performs processing according to a program stored in a storage unit or the like, thereby realizing the above-described functions.

[0124] In some embodiments, the light source 10 includes two or more light sources. In this case, each of the two or more light sources is provided corresponding to one or more openings formed in the iris diaphragm 21. The main control unit 101 can change at least one of the position and orientation (the orientation in the direction where the light intensity distribution is maximized) of each light source by controlling the movement mechanism provided corresponding to each of the two or more light sources.

[0125] (Storage Unit 102)

[0126] The storage unit 102 stores various computer programs and data. The computer programs include a calculation program and a control program for controlling the ophthalmologic apparatus 1 .

[0127] (Operation unit 110)

[0128] The operating unit 110 includes operating devices or input devices. The operating unit 110 includes buttons, switches (e.g., operating handles, operating knobs, etc.), and operating devices (e.g., a mouse, keyboard, etc.) provided on the ophthalmic apparatus 1. Furthermore, the operating unit 110 may include any operating device or input device, such as a trackball, operating panel, switches, buttons, and dials.

[0129] (Display unit 120)

[0130] The display unit 120 displays an image of the subject's eye E generated by the data processing unit 200. The display unit 120 is configured to include a display device such as a flat panel display such as an LCD (Liquid Crystal Display). Alternatively, the display unit 120 may include various display devices such as a touch panel provided in the housing of the ophthalmologic apparatus 1.

[0131] In addition, the operating unit 110 and the display unit 120 do not need to be configured as separate devices. For example, a device that integrates a display function and an operating function, such as a touch panel, can also be used. In this case, the operating unit 110 is configured to include the touch panel and a computer program. The operation content of the operating unit 110 is input to the control unit 100 as an electrical signal. In addition, a graphical user interface (GUI) displayed in the display unit 120 and the operating unit 110 can also be used to perform operations and input information. In some embodiments, the functions of the display unit 120 and the operating unit 110 are implemented by a touch screen.

[0132] (Other structures)

[0133] In some embodiments, the ophthalmic device 1 further comprises a fixation projection system. Figure 1In the structure of the optical system shown, the optical path of the fixation projection system is coupled with the optical path of the shooting optical system 40. The fixation projection system is capable of presenting an internal fixed sight mark or an external fixed sight mark to the eye E to be inspected. In the case of presenting the internal fixed sight mark to the eye E to be inspected, the fixation projection system includes an LCD that is controlled by the control unit 100 to display the internal fixed sight mark, and projects the fixation light beam output from the LCD to the fundus of the eye E to be inspected. The LCD is configured to be able to change the display position of the fixed sight mark on its screen. By changing the display position of the fixed sight mark on the LCD, the projection position of the fixed sight mark in the fundus of the eye E to be inspected can be changed. The display position of the fixed sight mark in the LCD can be specified by the user by using the operation unit 110.

[0134] 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).

[0135] For example, the XY alignment system projects a bright spot (in the infrared or near-infrared region) onto the eye E. The data processing unit 200 obtains an image of the anterior segment of the eye E after the bright spot is projected and calculates the displacement between the bright spot image drawn on the obtained anterior segment image and the alignment reference position. The control unit 100 uses a movement mechanism (not shown) to relatively move the device optical system and the eye E in a direction intersecting the optical axis to eliminate the calculated displacement.

[0136] For example, the Z alignment system projects infrared or near-infrared alignment light from a position offset from the optical axis of the apparatus optical system and receives the alignment light reflected from the anterior segment of the subject's eye E. The data processing unit 200 specifies the distance of the subject's eye E from the apparatus optical system based on the position where the alignment light is received, which varies depending on the distance from the subject's eye E to the apparatus optical system. The control unit 100 uses a movement mechanism (not shown) to relatively move the apparatus optical system and the subject's eye E in the direction of the optical axis so that the specified distance becomes the desired working distance.

[0137] In some embodiments, the alignment system functions by using two or more anterior segment cameras positioned at positions separated from the optical axis of the apparatus optical system. For example, as disclosed in Japanese Patent Application Laid-Open No. 2013-248376, the data processing unit 200 analyzes images of the anterior segment of the subject's eye E, acquired substantially simultaneously by the two or more anterior segment cameras, and uses known triangulation techniques to identify the three-dimensional position of the subject's eye E. The control unit 100 uses a movement mechanism (not shown) to move the apparatus optical system and the subject's eye E three-dimensionally relative to each other so that the optical axis of the apparatus optical system and the axis of the subject's eye E are approximately aligned and the distance between the apparatus optical system and the subject's eye E is a predetermined working distance.

[0138] As described above, in the ophthalmic device 1, the slit 22 (opening), the imaging site (fundus Ef), and the image sensor 51 (light-receiving surface) are arranged at substantially optically conjugate positions. By moving the light-receiving opening of the image sensor 51 in conjunction with the irradiation position of the illumination light, the ophthalmic device 1 can suppress the influence of unwanted scattered light while obtaining a clear image of the imaging site.

[0139] The data processing unit 200 is an example of an “image forming unit” according to the embodiment.

[0140] [Work]

[0141] Next, the operation of the ophthalmologic apparatus 1 will be described.

[0142] Figure 9A FIG. 1 is a diagram illustrating the operation of the ophthalmologic apparatus 1 according to the embodiment. Figure 9A In FIG. 1 , the vertical axis represents the deflection angle range (±22.5°) based on the scanning center as the imaging area in the fundus Ef, and the horizontal axis represents the time axis.

[0143] like Figure 9A As shown, the control unit 100 outputs a scanning control signal Scont to the optical scanner 30. The optical scanner 30 delays reception of the scanning control signal Scont from the control unit 100 by a predetermined time and changes the deflection surface in the deflection direction Dir corresponding to the scanning control signal Scont. This irradiates the fundus Ef with illumination light directed to the area corresponding to the deflection surface of the optical scanner 30 based on the scanning control signal Scont. In the image sensor 51, the aperture OR is opened in a rolling shutter manner in the imaging target area SR' of the light-receiving surface SR to receive return light from the area illuminated by the illumination light in the fundus Ef. The image sensor 51 then acquires the result of receiving the return light within the aperture OR.

[0144] exist Figure 9A In, through Figure 7 as well as Figure 8As shown, the optical scanner 30 is controlled to capture the image at the time T IMG In the first and last parts of the shooting range R IMG The outside of the (photographing target area) is also irradiated with illumination light (areas OS1 and OS2).

[0145] Figure 9B as well as Figure 9C Operation explanatory diagrams for comparing the embodiment with a comparative example of the embodiment are shown. Figure 9B It means Figure 9A Shooting time T IMG An enlarged view of the initial part. Figure 9C This means that in the comparative example of the embodiment, Figure 9B Here, in the comparative example of the embodiment, it is assumed that Figure 6 The control shown. Figure 9B as well as Figure 9C In, with Figure 9A The same reference numerals are assigned to the same parts, and description thereof will be appropriately omitted.

[0146] like Figure 9B As shown, the vertical width SW of the region OS1 corresponds to the slit width of the illumination light, and the horizontal width Ti of the region OS1 corresponds to the irradiation time of the illumination light. Figure 9B As shown in FIG. 1 , an area OS1 outside the imaging range is illuminated in the fundus Ef. Figure 9C As shown, the areas OS11 and OS12 are not illuminated in the fundus Ef. In particular, in the embodiment, the entire imaging range is illuminated, whereas in the comparative example of the embodiment, the area OS12 in the imaging range is not illuminated.

[0147] As described above, according to the embodiment, Figure 7 and Figure 8 By controlling as shown, the fluctuation of the irradiation time of the return light of the illumination light to all pixel groups in the imaging target area can be made substantially equal. As a result, a high-quality image of the fundus Ef without bright spots can be obtained.

[0148] <Modification>

[0149] The structure of the ophthalmologic apparatus according to the embodiment is not limited to the structure of the ophthalmologic apparatus 1 according to the embodiment. For example, the control unit may control the optical scanner 30 so as to shift the irradiation range IP′ from the outside of the imaging target region SR′ to reduce the influence of the unstable operating region of the optical scanner 30.

[0150] Hereinafter, an ophthalmologic apparatus according to a modified example of the embodiment will be described, focusing on differences from the ophthalmologic apparatus 1 according to the embodiment.

[0151] The configurations of the optical system and the control system of the ophthalmologic apparatus according to the modified example of the embodiment are the same as those of the optical system and the control system of the ophthalmologic apparatus 1 according to the embodiment.

[0152] The ophthalmologic apparatus according to the modification of the embodiment differs from the ophthalmologic apparatus 1 according to the embodiment mainly in the content of control of the optical scanner 30 by the control unit.

[0153] Specifically, in a modified example of the embodiment, the control unit controls the light scanner 30 in such a manner that the irradiation range is shifted from the outside of the photographic object area by a predetermined width that is larger than the width in the shift direction of the irradiation range IP' (the area corresponding to the illuminated area in the fundus Ef) in the light receiving surface SR of the image sensor 51.

[0154] In some embodiments, the predetermined width is the sum of the width of the irradiation range IP' on the light-receiving surface of the image sensor 51 in the shift direction and a width corresponding to the number of rows corresponding to the unstable operating region of the optical scanner 30. In some embodiments, the unstable operating region of the optical scanner 30 is the nonlinear operating region of the optical scanner 30. In some embodiments, the unstable operating region of the optical scanner 30 is the region from when the scanning control signal Scont is set for the optical scanner 30 until the optical scanner 30 operates within the stable operating region.

[0155] Figure 10 FIG. 1 is a diagram illustrating the operation of the ophthalmologic apparatus 1 according to a modified example of the embodiment. Figure 10 In, with Figure 7 The same reference numerals are assigned to the same parts, and description thereof will be appropriately omitted.

[0156] For example, Figure 10 As shown, Figure 7 Compared with the case shown in FIG. 1 , the irradiation range IP′ is further shifted from the outside of the imaging target region SR′ by the number of lines XR corresponding to the unstable operation region of the optical scanner 30. That is, the control unit 100 shifts the irradiation range IP′ from the outside of the imaging target region SR′ as shown in FIG. Figure 6 As shown, the optical scanner 30 is controlled so as to shift the width of the irradiation range IP' in the shift direction by the sum of the width corresponding to the unstable operating region of the optical scanner 30. This reduces fluctuations in the irradiation time of the return light of the illumination light for all pixels within the imaging target region SR' without being affected by the unstable operating region of the optical scanner 30.

[0157] Figure 11 An operation explanation diagram of an ophthalmologic apparatus according to a modified example of the embodiment is shown. Figure 11 In, with Figure 9A The same reference numerals are assigned to the same parts, and description thereof will be appropriately omitted.

[0158] like Figure 11 As shown, the control unit 100 outputs a scanning control signal Scont to the optical scanner 30. The optical scanner 30 delays the scanning control signal Scont from the control unit 100 by a predetermined time and changes the deflection surface in the deflection direction Dir corresponding to the scanning control signal Scont. In the image sensor 51, the aperture range OR is opened in a rolling shutter manner in the imaging target region SR' on the light-receiving surface SR to receive return light from the area illuminated by the illumination light in the fundus Ef. The result of receiving the return light is then acquired within the aperture range OR.

[0159] exist Figure 11 In, through Figure 10 As shown, the optical scanner 30 is controlled to capture the image at the time T IMG In the first and last parts of the shooting range R IMG The outside of the (image capture target area) is also irradiated with illumination light (areas OS21 and OS22).

[0160] As described above, according to this modified embodiment, fluctuations in the irradiation time of the return light of the illumination light for all pixels within the imaging target region SR' are reduced, without being affected by the unstable operating region of the optical scanner 30. As a result, a high-quality image of the fundus oculi Ef free of bright spots can be obtained without being affected by the unstable operating region of the optical scanner 30.

[0161] [Function / Effect]

[0162] The operations and effects of the ophthalmologic apparatus, the control method thereof, and the program according to the embodiment will be described.

[0163] According to some embodiments, an ophthalmic device (1) includes an illumination optical system (20), an optical scanner (30), a photographing optical system (40), a control unit (100, a main control unit 101), and an image forming unit (data processing unit 200). The illumination optical system generates slit-shaped illumination light. The optical scanner deflects the illumination light and guides the illumination light to the fundus (Ef) of the eye to be examined (E). The photographing optical system guides the return light of the illumination light from the fundus to the image sensor (51). The control unit controls the optical scanner. The image forming unit forms an image of the fundus based on the light reception result obtained in the photographing object area (SR') in the light receiving surface (SR) of the image sensor. The image sensor is configured to obtain the light reception result in the opening area (opening range OP) of the light receiving surface corresponding to the illumination area of the illumination light in the fundus, which is moved in a predetermined scanning direction by the optical scanner, in a rolling shutter manner. The control unit controls the optical scanner in such a manner that the irradiation time of the return light on each of the multiple light receiving elements in the photographing object area is approximately equal.

[0164] This configuration can reduce fluctuations in the irradiation time of the return light in the imaging target area, thereby enabling a high-quality image of the subject's eye (fundus) free of bright spots to be obtained in a short imaging time.

[0165] In some embodiments, in an image sensor, a group of light-receiving elements arranged in a row direction orthogonal to a shift direction of an opening area shifted corresponding to an illumination area includes a plurality of light-receiving elements arranged in a column direction, a width in a shift direction of an irradiation range (IP') corresponding to the illumination area in a light-receiving surface has a width equivalent to two or more rows, and a control unit controls the light scanner in such a manner that the irradiation range is shifted in the shift direction by a predetermined number of rows from the outside of the photographic object area.

[0166] According to this configuration, it is possible to reduce fluctuations in the irradiation time of the return light on the imaging target area through simple control without adding a new configuration.

[0167] In some embodiments, the control unit controls the optical scanner so that the irradiation range is shifted from the outside of the imaging target area by a width corresponding to at least a number of lines.

[0168] According to this configuration, fluctuations in the irradiation time of the return light in the imaging target area can be reduced by simple control, and thus a high-quality image of the subject's eye can be easily obtained in a short imaging time.

[0169] In some embodiments, the control unit controls the optical scanner so that the irradiation range is shifted from the outside of the imaging target area by a width in a shift direction of an area corresponding to the illumination area on the light receiving surface.

[0170] According to this configuration, since the irradiation time of the return light on all the light receiving elements in the imaging target area can be made substantially equal by simple control, a high-quality image of the eye to be inspected can be easily obtained in a short imaging time.

[0171] In some embodiments, the control unit controls the optical scanner so that the irradiation range is shifted from the outside of the imaging target area by a predetermined width greater than a width in the shift direction of an area corresponding to the illumination area on the light receiving surface.

[0172] According to this configuration, it is possible to easily obtain a high-quality image of the eye to be inspected in a short imaging time while reducing the influence of the unstable operating region of the optical scanner.

[0173] In some embodiments, the predetermined width is the sum of the width of a region of the light-receiving surface corresponding to the illumination region in the shift direction and a width corresponding to the number of lines corresponding to the unstable operating region of the optical scanner.

[0174] According to this configuration, a high-quality image of the eye to be inspected can be easily obtained in a short imaging time without being affected by the unstable operating region of the optical scanner.

[0175] In some embodiments, the image sensor is a CMOS image sensor.

[0176] According to this configuration, it is possible to reduce fluctuations in the irradiation time of the return light in the imaging subject area with a simple configuration and at low cost.

[0177] In some embodiments, a control method for an ophthalmic device (1) includes: an illumination optical system (20) for generating slit-shaped illumination light; a light scanner (30) for deflecting the illumination light and guiding the illumination light to a fundus (Ef) of an eye (E) to be examined; a photographing optical system (40) for guiding return light of the illumination light from the fundus to an image sensor (51), the image sensor (51) being configured to acquire light reception results in an opening area of a light receiving surface (SR) corresponding to an illumination area of the fundus by the illumination light, which is moved in a predetermined scanning direction by the light scanner; and a control unit (100, main control unit 101) for controlling the light scanner. The control method includes: a control step of controlling the light scanner so that the irradiation time of the return light on each of a plurality of light receiving elements of a photographing target area (SR') on the light receiving surface of the image sensor is substantially equal; and an image forming step of forming an image of the fundus based on the light reception results acquired in the photographing target area.

[0178] This method can reduce the fluctuation of the irradiation time of the return light in the imaging target area, thereby obtaining a high-quality image of the subject's eye (fundus) without bright spots in a short imaging time.

[0179] In some embodiments, in an image sensor, a group of light-receiving elements arranged in a row direction orthogonal to a shift direction of an opening area shifted corresponding to an illumination area includes a plurality of light-receiving elements arranged in a column direction, and a width in a shift direction of an irradiation range (IP') corresponding to the illumination area in a light-receiving surface has a width equivalent to two or more rows, and in a control step, the light scanner is controlled in such a manner that the irradiation range is shifted in a shift direction by a predetermined number of rows from the outside of the photographic object area.

[0180] According to this method, the fluctuation of the irradiation time of the return light on the imaging target area can be reduced by simple control without adding a new structure.

[0181] In some embodiments, in the controlling step, the optical scanner is controlled so that the irradiation range is shifted from the outside of the imaging target area by a width corresponding to at least a number of lines.

[0182] According to this method, since the fluctuation of the irradiation time of the return light in the imaging target area can be reduced by simple control, a high-quality image of the eye to be inspected can be easily obtained in a short imaging time.

[0183] In some embodiments, in the controlling step, the optical scanner is controlled so that the irradiation range is shifted from the outside of the imaging target area by a width in a shift direction of an area corresponding to the illumination area on the light receiving surface.

[0184] According to this method, since the irradiation time of the return light can be made substantially equal in all the light receiving elements in the imaging target area by simple control, a high-quality image of the eye to be inspected can be easily obtained in a short imaging time.

[0185] In some embodiments, in the controlling step, the optical scanner is controlled so that the irradiation range is shifted from the outside of the imaging target area by a predetermined width greater than a width in the shift direction of an area corresponding to the illumination area on the light receiving surface.

[0186] According to this method, it is possible to easily obtain a high-quality image of the eye to be inspected in a short imaging time while reducing the influence of the unstable operating region of the optical scanner.

[0187] In some embodiments, the predetermined width is the sum of the width of a region of the light-receiving surface corresponding to the illumination region in the shift direction and a width corresponding to the number of lines corresponding to the unstable operating region of the optical scanner.

[0188] According to this method, a high-quality image of the eye to be inspected can be easily obtained in a short imaging time without being affected by the unstable operating area of the optical scanner.

[0189] In some embodiments, the image sensor is a CMOS image sensor.

[0190] According to this method, fluctuations in the irradiation time of the return light in the imaging subject area can be reduced at low cost.

[0191] Some programs according to the embodiments cause a computer to execute each step of any of the above-described methods for controlling an ophthalmic apparatus.

[0192] This procedure can reduce fluctuations in the irradiation time of the return light in the imaging target area, thereby enabling the acquisition of a high-quality image of the subject's eye (fundus) free of bright spots in a short imaging time.

[0193] The embodiment and its modified examples shown above are merely examples for implementing the present invention, and those who wish to implement the present invention can make arbitrary modifications, omissions, additions, etc. within the scope of the gist of the present invention.

[0194] In the above-mentioned embodiment, the ophthalmic device may have any function that can be used in the field of ophthalmology, such as an axial length measurement function, an intraocular pressure measurement function, an optical coherence tomography (OCT) function, and an ultrasonic examination function. In addition, the axial length measurement function is realized by an optical coherence tomography instrument or the like. In addition, the axial length measurement function can also be achieved by projecting light onto the eye to be inspected, adjusting the position of the optical system in the Z direction (front-back direction) relative to the eye to be inspected, and detecting the return light from the fundus, thereby measuring the axial length of the eye to be inspected. The intraocular pressure measurement function is realized by a tonometer or the like. The OCT function is realized by an optical coherence tomography instrument or the like. The ultrasonic examination function is realized by an ultrasonic diagnostic device or the like. In addition, the present invention can also be applied to a device (compound machine) having two or more such functions.

[0195] In some embodiments, a program for causing a computer to execute the method for controlling an ophthalmic device is provided. This program can be stored in any non-transitory recording medium that is readable by a computer. The recording medium can be an electronic medium using magnetic, optical, optical-magnetic, semiconductor, or the like. Typically, the recording medium is a magnetic tape, a magnetic disk, an optical disc, a magnetic-optical disk, a flash memory, a solid-state drive, or the like. In addition, the program can be transmitted and received via a network such as the Internet or a local area network (LAN).

[0196] (Explanation of Reference Numerals)

[0197] 1: Ophthalmic devices

[0198] 10: Light Source

[0199] 20: Illumination optical system

[0200] 21: Iris aperture

[0201] 22: Rift

[0202] 23, 41, 44, 48: Relay lenses

[0203] 30: Optical Scanner

[0204] 35: Projection optical system

[0205] 40: Shooting Optical System

[0206] 42: Black dot board

[0207] 43: Reflector

[0208] 45: Hole Mirror

[0209] 46: Objective lens

[0210] 47: Focusing lens

[0211] 49: Imaging lens

[0212] 50: Camera

[0213] 51: Image sensor

[0214] 100: Control Department

[0215] 101: Main control unit

[0216] 102: Storage

[0217] 200: Data Processing Department

[0218] E: Eye to be examined

[0219] Ef: Fundus

[0220] IP, IP': irradiation range

[0221] OP: Opening range

[0222] SR: light-receiving surface

[0223] SR': Subject area

Claims

1. An ophthalmic device, characterized in that include: an illumination optical system for generating slit-shaped illumination light; an optical scanner that deflects the illumination light and guides the illumination light to the fundus of the eye to be inspected; a photographing optical system that guides return light of the illumination light from the fundus to an image sensor; a control unit for controlling the optical scanner; as well as an image forming unit that forms an image of the fundus based on a light reception result acquired in a photographing subject area on a light receiving surface of the image sensor, The image sensor is configured to acquire light reception results in an opening area of the light receiving surface corresponding to an illumination area of the illumination light in the fundus, which is moved in a predetermined scanning direction by the light scanner, in a rolling shutter manner. In the image sensor, a group of light receiving elements arranged in a row direction orthogonal to a shift direction of the opening area shifted corresponding to the illumination area includes a plurality of light receiving elements arranged in a column direction. The width of the irradiation range corresponding to the illumination area on the light receiving surface in the shift direction has a width corresponding to two or more rows. The control unit controls the light scanner in such a manner that the irradiation range is shifted from the outside of the photographic object area by a predetermined width in units of a predetermined number of rows, and the irradiation time of the return light on each of the multiple light receiving elements in the photographic object area is approximately equal, and the predetermined width is the sum of the width of the area in the light receiving surface corresponding to the illumination area in the shift direction and the width corresponding to the number of rows corresponding to the unstable working area of the light scanner.

2. The ophthalmic device according to claim 1, wherein The control unit controls the optical scanner so that the irradiation range is shifted from the outside of the imaging target area by a width corresponding to at least a number of lines.

3. The ophthalmic device according to claim 1 or 2, wherein: The image sensor is a CMOS image sensor.

4. A method for controlling an ophthalmic device, characterized in that: The ophthalmic device comprises: an illumination optical system for generating slit-shaped illumination light; an optical scanner that deflects the illumination light and guides the illumination light to the fundus of the eye to be inspected; an imaging optical system that guides return light of the illumination light from the fundus to an image sensor, the image sensor being configured to acquire light reception results in an opening area of a light receiving surface in the fundus corresponding to an illumination area of the illumination light, the light scanner being moved in a predetermined scanning direction, in a rolling shutter manner; and a control unit that controls the optical scanner, In the image sensor, the light receiving element group arranged in a row direction orthogonal to a shift direction of the opening area shifted corresponding to the illumination area includes a plurality of light receiving elements arranged in a column direction. The width of the irradiation range corresponding to the illumination area on the light receiving surface in the shift direction has a width corresponding to two or more rows. The control method of the ophthalmic device comprises: a control step of controlling the light scanner so that the irradiation range is shifted by a predetermined width in units of a predetermined number of lines from the outside of the photographic subject area on the light-receiving surface of the image sensor, and the irradiation time of the return light on each of the plurality of light-receiving elements in the photographic subject area is substantially equal, the predetermined width being the sum of a width in the shift direction of an area on the light-receiving surface corresponding to the illumination area and a width corresponding to the number of lines corresponding to an unstable operation area of the light scanner; and An image forming step forms an image of the fundus based on the light reception result obtained in the photographing object area.

5. The control method of an ophthalmic device according to claim 4, wherein: In the control step, the optical scanner is controlled so that the irradiation range is shifted from the outside of the imaging target area by a width corresponding to at least the number of lines.

6. The method for controlling an ophthalmic device according to claim 4 or 5, wherein: The image sensor is a CMOS image sensor.

7. A recording medium, wherein the recording medium is a computer-readable non-transitory recording medium, characterized in that: The recording medium stores a program that causes a computer to execute each step of the method for controlling an ophthalmologic apparatus according to any one of claims 4 to 6 .

Images