Ophthalmic device and control method thereof

Abstract

To provide an ophthalmologic apparatus capable of acquiring an ocular fundus image of a desired imaging region in the ocular fundus without changing a visual line direction of an eye to be examined, and to provide a control method thereof.SOLUTION: An ophthalmologic apparatus includes: an ocular fundus imaging part for imaging the ocular fundus of an eye to be examined; a relative movement part for relatively moving the ocular fundus imaging part with respect to the eye to be examined; a fixation target presentation part which is provided so as to move with the ocular fundus imaging part in an integrated manner for presenting a fixation target to the eye to be examined, which can move the fixation target; and a movement control part for driving the relative movement part according to the movement of the fixation target by the fixation target presentation part, and causing the ocular fundus imaging part to move relatively with a direction and an amount of movement for cancelling the movement of the fixation target.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to an ophthalmologic apparatus for photographing the fundus of a subject's eye and a control method thereof. [Background technology]

[0002] Fundus cameras (ophthalmic devices) that photograph the fundus of a subject's eye are well known (see Patent Documents 1 to 5). Fundus images photographed by these fundus cameras are used for diagnosing the fundus, etc. For such diagnosis, a fundus image of a wide area of ​​the fundus may be required, but a fundus camera cannot photograph a detailed fundus image of a wide area of ​​the fundus in a single shot.

[0003] Therefore, the fundus camera described in each of the above patent documents repeatedly photographs the fundus while changing the position of the fixation target presented to the subject's eye multiple times, i.e., while changing the line of sight (fixation direction) of the subject's eye, obtains fundus images by dividing the fundus into multiple photographing areas. Next, the fundus camera connects the fundus images of each photographing area to generate a panoramic image (wide-area image) of the fundus. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-161439 A [Patent Document 2] JP 2006-325936 A [Patent Document 3] JP 2017-184874 A [Patent Document 4] Patent No. 3833529 [Patent Document 5] Patent No. 5080944 Summary of the Invention [Problem to be solved by the invention]

[0005] In the ophthalmologic devices described in the above patent documents, when generating a panoramic image of the fundus, the fundus is photographed repeatedly while changing the position of the fixation target presented to the subject's eye, but some subjects (patients) may lose sight of the fixation target after changing its position. In this case, the photographing of at least a part of the photographing area of ​​the fundus may fail, and a good fundus image may not be obtained, resulting in a risk of not being able to obtain a good panoramic image.

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide an ophthalmic apparatus and a control method thereof that can acquire a fundus image of a desired photographing area within the fundus without changing the line of sight of the subject eye. [Means for solving the problem]

[0007] An ophthalmic device for achieving the object of the present invention comprises a fundus photography unit which photographs the fundus of the test eye, a relative movement unit which moves the fundus photography unit relative to the test eye, a fixation target presentation unit which is arranged to be movable integrally with the fundus photography unit and presents a fixation target to the test eye and is capable of moving the fixation target, and a movement control unit which drives the relative movement unit in response to movement of the fixation target by the fixation target presentation unit, thereby moving the fundus photography unit relatively in a direction and by an amount of movement which cancels out the movement of the fixation target.

[0008] With this ophthalmic device, the fundus photography area photographed by the fundus photography unit can be changed while maintaining the line of sight of the test eye constant, allowing the desired photography area within the fundus to be photographed by the fundus photography unit.

[0009] In an ophthalmologic apparatus according to another aspect of the present invention, the fundus photographing unit photographs the fundus at a plurality of photographing positions in response to relative movement by the movement control unit, thereby acquiring fundus images of a plurality of photographing regions in the fundus. This makes it possible to change the photographing region of the fundus photographed by the fundus photographing unit while maintaining the line of sight of the subject's eye constant, and obtain fundus images of a desired plurality of photographing regions in the fundus.

[0010] In an ophthalmologic apparatus according to another aspect of the present invention, a fixation target presenting unit moves a fixation target to a plurality of positions in sequence, and in response to the movement of the fixation target by the fixation target presenting unit, the movement control unit repeatedly moves the fundus photographing unit relative to the fixation target and the fundus photographing unit photographs a new photographing area. This makes it possible to change the photographing area of ​​the fundus photographed by the fundus photographing unit while keeping the line of sight of the subject's eye constant, and obtain fundus images of desired photographing areas in the fundus.

[0011] In the ophthalmologic apparatus according to another aspect of the present invention, a wide-area image generating unit is provided that generates a wide-area image of the fundus based on the fundus image of each photographing area photographed by the fundus photographing unit, thereby making it possible to generate a good wide-area image.

[0012] An ophthalmologic apparatus according to another aspect of the present invention includes a display unit that displays the wide area image generated by the wide area image generating unit.

[0013] In an ophthalmologic apparatus according to another aspect of the present invention, the fundus photographing unit has a function of photographing a special fundus image of a different type from the fundus image, and includes an operation unit for performing a selection operation to select a selected photographing area, which is a photographing area for photographing a special fundus image, from among a plurality of photographing areas, a special fundus image acquisition control unit for controlling the fixation target presenting unit, the relative movement unit, and the fundus photographing unit based on the selection operation to acquire the special fundus image of the selected photographing area, and a first display control unit for displaying the special fundus image superimposed on the fundus image corresponding to the selected photographing area in the wide-area image displayed on the display unit. This makes it possible to obtain an overview of the entire fundus based on the wide-area image, while diagnosing the selected photographing area in detail in the fundus based on the special fundus image.

[0014] In an ophthalmologic apparatus according to another aspect of the present invention, the wide-area image generating unit links, each time a new fundus image is captured by the fundus photographing unit, the new fundus image to a fundus image captured by the fundus photographing unit prior to the new fundus image, and causes the display unit to start displaying the newly linked fundus image each time the wide-area image generating unit links fundus images. This makes it possible to display the process of generating the wide-area image in real time, thereby making it possible to observe fundus images of multiple photographing areas in real time.

[0015] In an ophthalmologic apparatus according to another aspect of the present invention, the wide-area image generating unit includes an information generating unit that generates image generation information for generating a wide-area image from a fundus image for each photographing area, and a storage unit that stores the fundus image for each photographing area and the image generation information generated by the information generating unit, and the wide-area image generating unit generates a wide-area image based on the fundus image for each photographing area and the image generation information stored in the storage unit in response to a display operation of the wide-area image. This makes it possible to generate a wide-area image in a short time and display it on the display unit while suppressing an increase in the storage capacity of the storage unit.

[0016] An ophthalmologic apparatus according to another aspect of the present invention includes an anterior-segment imaging unit that continuously images an anterior segment of a subject's eye, a pupil diameter detection unit that detects a pupil diameter of the subject's eye based on the anterior-segment image captured by the anterior-segment imaging unit each time the anterior-segment imaging unit images the anterior segment, and an exposure control unit that controls exposure of the fundus imaging unit based on the detection result of the pupil diameter detection unit and uniforms the brightness of the fundus image for each imaging area. This makes it possible to uniformize the brightness of the wide-area image and improve the image quality of the wide-area image.

[0017] A control method for an ophthalmic apparatus for achieving the object of the present invention includes a fundus photographing unit for photographing the fundus of the test eye, a relative movement unit for moving the fundus photographing unit relative to the test eye, and a fixation target presenting unit that is arranged to be movable integrally with the fundus photographing unit and presents a fixation target to the test eye and is capable of moving the fixation target, and includes a movement control step of driving the relative movement unit in accordance with movement of the fixation target by the fixation target presenting unit to move the fundus photographing unit relatively in a direction and by an amount of movement that cancels out the movement of the fixation target.

[0018] A control method for an ophthalmic device according to another aspect of the present invention includes a photographing step in which the fundus photographing unit photographs the fundus at a plurality of photographing positions in accordance with the relative movement of the fundus photographing unit in the movement control step, thereby obtaining fundus images of a plurality of photographing areas within the fundus. Effect of the Invention

[0019] The present invention can obtain a fundus image of a desired photographing area in the fundus without changing the line of sight of the subject's eye. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a perspective view of a fundus camera according to a first embodiment, as viewed from an examiner's side. [Diagram 2] FIG. 2 is a perspective view of a camera body constituting a fundus camera, as viewed from the subject side. [Diagram 3] FIG. 1 is a block diagram of a fundus camera according to a first embodiment. [Figure 4] 4A to 4C are explanatory diagrams for explaining each photographing area of ​​the fundus in a panoramic photographing mode. [Diagram 5] FIG. 13 is an explanatory diagram showing a comparative example in which each photographing area of ​​the fundus is photographed in sequence by a conventional method. [Figure 6] FIG. 2 is an explanatory diagram showing a method for photographing each photographing area of ​​the fundus in sequence. [Figure 7] 3 is an explanatory diagram showing an example of a panoramic image generated by a panoramic image generating unit; FIG. [Figure 8] 4 is a flowchart showing the flow of panoramic photography of a fundus by the fundus camera of the first embodiment. [Figure 9] FIG. 11 is a block diagram showing the configuration of a fundus camera according to a second embodiment. [Figure 10] 13 is an explanatory diagram showing a panoramic image before a special fundus image is superimposed and displayed by a display control unit. FIG. [Figure 11] 13 is an explanatory diagram showing a panoramic image after a special fundus image is superimposed and displayed by a display control unit. FIG. [Figure 12]13 is a flowchart showing a process of capturing a special fundus image by a fundus camera according to a second embodiment, and a process of superimposing and displaying the special fundus image on a panoramic image. [Figure 13] FIG. 11 is a block diagram showing the configuration of a fundus camera according to a third embodiment. [Figure 14] 11 is a time chart showing an example of the timing of photographing a fundus image by a fundus photographing section, a process of linking the fundus images by an image processing section, and a process of displaying a new fundus image by a display section. [Figure 15] 13 is an explanatory diagram showing a specific example of a new fundus image displayed on the display unit. FIG. [Figure 16] 13 is an explanatory diagram showing a specific example of a new fundus image displayed on the display unit. FIG. [Figure 17] FIG. 13 is a block diagram showing the configuration of a fundus camera according to a fourth embodiment. [Figure 18] FIG. 13 is a block diagram showing the configuration of a fundus camera according to a fifth embodiment. [Figure 19] 13 is a flowchart showing the flow of panoramic photography of a fundus by a fundus camera according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] [First embodiment] Fig. 1 is a perspective view of a fundus camera 10 of the first embodiment as viewed from the examiner's side. Fig. 2 is a perspective view of a camera body 10a constituting the fundus camera 10 as viewed from the subject's side. In the figure, the X direction is the left-right direction based on the subject, the Y direction is the up-down direction, and the Z direction is the front-rear direction (also called the working distance direction) parallel to the front direction approaching the subject and the rear direction away from the subject.

[0022] 1 and 2, a fundus camera 10 corresponds to an ophthalmologic apparatus of the present invention, and photographs a fundus Ef of a subject's eye E shown in Fig. 3 described later. The fundus camera 10 includes a camera body 10a and a display unit 18, and has a normal photographing mode and a panoramic photographing mode as photographing modes for photographing the fundus Ef.

[0023] The normal photography mode is a mode in which the fundus Ef (see FIG. 3) is photographed only once. Since the fundus Ef does not fall within the range (angle of view) of one photographing by the fundus camera 10, the normal photography mode obtains a fundus image D of a portion of the photographing area of ​​the fundus Ef (central part of the fundus, peripheral part of the fundus). The panoramic photography mode is a mode in which so-called panoramic photography is performed in which the fundus Ef is divided into a plurality of photographing areas (areas to be photographed, areas to be photographed) and photographed, and a panoramic image DP, which is a wide-area image of the fundus Ef, is generated based on the fundus images D of each photographing area.

[0024] <Camera body> The camera body 10a includes a base 11, a face support unit 12, an electric drive mechanism 14, and a fundus camera head 16. The base 11 is provided with the face support unit 12 and the electric drive mechanism 14.

[0025] The face support part 12 is provided integrally with the base 11 at a position on the front side (subject side) in the Z direction of the fundus camera head 16. The face support part 12 has a chin rest 12a and a forehead rest 12b whose positions can be adjusted in the Y direction (up and down direction), and supports the subject's face in a position facing the fundus camera head 16.

[0026] In addition, the face support unit 12 is provided with an external fixation lamp 15. The external fixation lamp 15 has a light source that emits fixation light, and the position of the light source and the emission direction of the fixation light can be adjusted arbitrarily. This external fixation lamp 15 is used for external fixation. External fixation is a fixation method in which the position of the light source of the external fixation lamp 15 is adjusted to rotate the subject's eye E (see FIG. 3) in an arbitrary direction, or to rotate it more than in internal fixation, or to adjust the direction of the subject's eye E by guiding the line of sight of the subject's eye E or the fellow eye when internal fixation cannot be performed.

[0027] The electric drive mechanism 14 constitutes the relative movement unit of the present invention, and a known actuator such as a motor drive mechanism is used for the electric drive mechanism 14. The electric drive mechanism 14 moves the fundus camera head 16 relative to the subject's eye E (see FIG. 3). The electric drive mechanism 14 includes an XYZ drive unit 14a and a swing-tilt drive unit 14b provided in the XYZ drive unit 14a.

[0028] The XYZ driving unit 14a moves the swing-tilt driving unit 14b and the fundus camera head 16 in the XYZ directions relative to the base 11. This allows the fundus camera head 16 to move in the XYZ directions relative to the subject's eye E (see FIG. 3). In addition, an operation unit 17 is provided on the XYZ driving unit 14a.

[0029] The swing / tilt drive unit 14b holds the fundus camera head 16 and swings [rotates (swings) around a rotation axis parallel to the Y axis] and tilts [rotates (swings) around a rotation axis parallel to the X axis] of the fundus camera head 16. This allows the fundus camera head 16 to swing and tilt with respect to the subject's eye E (see FIG. 3).

[0030] The operation unit 17 is provided on the XYZ drive unit 14a and at a position on the rear side (examiner side) in the Z direction of the fundus camera head 16. The operation unit 17 is provided with an operation lever 17a as well as operation buttons for performing various operations of the camera body 10a (fundus camera 10). Note that the operation unit 17 may be an input device 17b such as a keyboard and a mouse externally connected to the camera body 10a.

[0031] The operation lever 17a is an operation member for manually moving the fundus camera head 16 in each of the X, Y and Z directions. For example, when the operation lever 17a is tilted in the Z direction (front-back direction) or the X direction (left-right direction), the fundus camera head 16 is moved in the Z direction or the X direction by the above-mentioned XYZ drive unit 14a. When the operation lever 17a is rotated around its longitudinal axis, the fundus camera head 16 is moved in the Y direction (up-down direction) by the XYZ drive unit 14a according to the direction of the rotation. Furthermore, a photography switch is provided on the top of the operation lever 17a.

[0032] 3, the fundus camera head 16, in normal photography mode and panoramic photography mode, presents a fixation target 23 to the subject's eye E, photographs the fundus Ef, and outputs a fundus image D. An objective lens 16a is provided on the front side of the fundus camera head 16 in the Z direction, and an eyepiece lens 16b is provided on the rear side in the Z direction.

[0033] The display unit 18 may be implemented by any of various known displays such as a liquid crystal display, and displays a fundus image D captured by the fundus camera head 16, a panoramic image DP generated by a control device 30 (see FIG. 3) described below, various setting screens, etc. The display unit 18 may be provided integrally with the camera body 10a.

[0034] 3 is a block diagram of the fundus camera 10 of the first embodiment. As shown in FIG. 3, the fundus camera head 16 is provided with a fundus photographing section 20 and a fixation target presenting section 22.

[0035] As shown in Fig. 5 and Fig. 6 described later, the fundus photographing section 20 includes an objective lens 16a provided in the fundus camera head 16, a photographing optical system 21a including a focus lens, an image sensor 21b, and an illumination section (not shown). The fundus photographing section 20 irradiates illumination light from the illumination section onto the fundus Ef through the objective lens 16a, photographs the fundus Ef illuminated with the illumination light through the objective lens 16a and the photographing optical system 21a with the image sensor 21b, and outputs a fundus image D (see the above-mentioned patent documents). In the fundus camera head 16, the examiner can directly observe the fundus Ef illuminated with the illumination light through the eyepiece 16b.

[0036] Although not shown, the fundus photographing unit 20 is provided with an alignment detection optical system and a focus optical system. The alignment detection optical system projects an alignment index onto the anterior segment Ea of the subject's eye E through the objective lens 16a, and photographs the anterior segment Ea onto which the alignment index is projected to obtain an anterior segment image (see Patent Document 3 above). This anterior segment image is used to align the fundus camera head 16 with the subject's eye E.

[0037] The focusing optical system generates focusing light (e.g., a split index) for focusing on the fundus Ef, irradiates the focusing light from the objective lens 16a onto the fundus Ef, and captures an image of the reflected light of the focusing light reflected by the fundus Ef (see Patent Document 3 above). An imaging signal of the reflected light of the focusing light captured by the focusing optical system is used for adjusting the focus of the fundus photographing unit 20 on the fundus Ef.

[0038] The fixation target presenting unit 22 is provided inside the fundus camera head 16, and therefore can move integrally with the fundus photographing unit 20 in response to the movement (swing) of the fundus camera head 16. For example, a dot matrix liquid crystal display or a matrix light emitting diode capable of displaying the fixation target 23 is used as the fixation target presenting unit 22. The fixation target presenting unit 22 is used for internal fixation, which presents (presents) the fixation target 23 to the subject's eye E by projecting the fixation light of the displayed fixation target 23 onto the subject's eye E through the objective lens 16a. The display position and display mode (shape, etc.) of the fixation target 23 by the fixation target presenting unit 22 can be set arbitrarily.

[0039] <Control device> The control device 30 is provided, for example, inside the base 11, the electric drive mechanism 14, or the fundus camera head 16. As the control device 30, a processing device such as a computer that executes various types of calculation processing and control processing is used. The control device 30 may be provided outside the camera body 10a.

[0040] The control device 30 includes a general control unit 32, a storage unit 34, and a panoramic image generating unit 36. The general control unit 32 of the control device 30 is also connected to the above-mentioned electric drive mechanism 14, fundus camera head 16, operation unit 17, and display unit 18. In addition, in the panoramic photography mode, the operation unit 17 accepts a selection operation for selecting multiple photographing areas of the fundus Ef for performing panoramic photography.

[0041] The overall control unit 32 overall controls the operation of each unit of the fundus camera 10. In the normal photography mode and the panoramic photography mode, the overall control unit 32 controls the photography of the fundus Ef by the fundus photography unit 20, the presentation of the fixation target 23 to the subject's eye E by the fixation target presenting unit 22, and the relative movement of the fundus camera head 16 by the electric drive mechanism 14.

[0042] In addition, in the panoramic shooting mode, the overall control unit 32 controls the fixation target presenting unit 22, the electric drive mechanism 14, and the fundus photographing unit 20, as will be described in detail later, to move the display position of the fixation target 23 and the fundus camera head 16 so that the line of sight of the test eye E is maintained constant, while causing the fundus photographing unit 20 to photograph multiple shooting areas of the fundus Ef.

[0043] The functions of the general control unit 32 are realized by using various processors. The various processors include a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), and a programmable logic device (e.g., simple programmable logic devices (SPLD), complex programmable logic devices (CPLD), and field programmable gate arrays (FPGA)). The various functions of the general control unit 32 may be realized by one processor, or may be realized by multiple processors of the same type or different types.

[0044] The storage unit 34 stores image data of a fundus image D captured by the fundus photographing unit 20, in addition to a program executed by the overall control unit 32 described below. Furthermore, in the panoramic photography mode, the storage unit 34 sequentially stores a new fundus image D every time the fundus image D of a new photographing area is captured by the fundus photographing unit 20. Although not shown in the figure, the storage unit 34 in the first embodiment also stores a panoramic image DP generated by a panoramic image generating unit 36 ​​described below.

[0045] The overall control unit 32 functions as a fixation target control unit 40, an alignment detection unit 42, a movement control unit 44, an imaging control unit 46, a fundus image acquisition unit 48, and a display control unit 50 when photographing the fundus of the subject's eye E (in normal imaging mode and in panoramic imaging mode). Note that what is described as a "unit" of the overall control unit 32 (control device 30) may be a "circuit", a "device", or a "equipment". In other words, what is described as a "unit" may be composed of firmware, software, hardware, or a combination of these.

[0046] The fixation target control unit 40 controls the display position of the fixation target 23 by the fixation target presenting unit 22, thereby controlling the presentation of the fixation target 23 to the subject's eye E. In the normal imaging mode, the fixation target control unit 40 controls the fixation target presenting unit 22 to display the fixation target 23 at a display position corresponding to the imaging of an arbitrary imaging area (e.g., the center of the fundus, the peripheral part of the fundus, etc.) in the fundus Ef specified by the operation unit 17, etc., thereby presenting the fixation target 23 to the subject's eye E.

[0047] In addition, in the panoramic photography mode, the fixation target control unit 40 controls the fixation target presenting unit 22 to move the fixation target 23 to a display position corresponding to photography of each of a plurality of photography areas of the fundus Ef in order, thereby presenting the fixation target 23 to the subject's eye E in order for each display position (see FIG. 6 described later). Note that each photography area of ​​the fundus Ef is determined in advance by a selection operation on the operation unit 17, and the display position of the fixation target 23 for each photography area by the fixation target presenting unit 22 is also determined in advance.

[0048] Before the fundus photographing unit 20 photographs the fundus Ef, the alignment detection unit 42 performs alignment detection to detect the three-dimensional position of the subject's eye E based on an anterior eye image acquired from the alignment detection optical system of the fundus photographing unit 20 described above (see Patent Document 3). Then, the alignment detection unit 42 outputs the alignment detection result to the movement control unit 44.

[0049] The movement control unit 44 controls the driving of the electric drive mechanism 14. Before the fundus photographing unit 20 photographs the fundus Ef, the movement control unit 44 drives the XYZ driving unit 14a to move the fundus camera head 16 in the XYZ directions based on the alignment detection result input from the alignment detection unit 42, thereby aligning the fundus camera head 16 with the subject's eye E.

[0050] In addition, as shown in Figure 6 described below, in panoramic shooting mode, the movement control unit 44 drives the swing-tilt driving unit 14b to perform at least one of swinging and tilting (hereinafter simply referred to as rocking) of the fundus camera head 16 so as to cancel out the movement of the display position of the fixation target 23 by the fixation target presenting unit 22.

[0051] The photographing control unit 46 controls focus adjustment of the fundus photographing unit 20 before photographing the fundus Ef by the fundus photographing unit 20. Specifically, the photographing control unit 46 executes focus adjustment of the fundus photographing unit 20 with respect to the fundus Ef, i.e., autofocus, based on an imaging signal acquired from the focus optical system of the fundus photographing unit 20 described above before photographing the fundus Ef (see Patent Document 3 above).

[0052] Furthermore, the photography control unit 46 controls photography of the fundus Ef by the fundus photography unit 20. In the normal photography mode, the photography control unit 46 causes the fundus photography unit 20 to photograph the fundus Ef simultaneously with the completion of alignment of the fundus camera head 16 with respect to the subject's eye E or when the photography switch of the operation lever 17a is pressed.

[0053] On the other hand, in the panoramic photography mode, the photography control unit 46 controls photography of each photography area of ​​the fundus Ef by the fundus photography unit 20. The photography control unit 46 causes the fundus photography unit 20 to photograph the photography area each time the fundus camera head 16 is moved to a photography position where each photography area of ​​the fundus Ef can be photographed in response to the swing of the fundus camera head 16 by the swing-tilt drive unit 14b (see FIG. 6 described later). As a result, the fundus photography unit 20 photographs a fundus image D of each photography area of ​​the fundus Ef in order.

[0054] <Panorama shooting mode> Below, we will explain in detail the operation of each part of the fundus camera 10 in the panoramic shooting mode, in particular the control of the display position of the fixation target 23 of the fixation target presenting unit 22 by the fixation target control unit 40, the oscillation of the fundus camera head 16 by the movement control unit 44, and fundus photography by the photography control unit 46.

[0055] 4 is an explanatory diagram for explaining each photographing area of ​​the fundus Ef in the panoramic photographing mode. As shown in FIG. 4, in the panoramic photographing mode of this embodiment, the fundus Ef is divided into, for example, nine photographing areas, specifically, the first photographing area Ef1 to the ninth photographing area Ef9, and the first photographing area Ef1 to the ninth photographing area Ef9 are photographed in order by the fundus photographing unit 20. Note that the first photographing area Ef1 is the center of the fundus, and the second photographing area Ef2 to the ninth photographing area Ef9 are peripheral areas of the fundus located diagonally above, below, left, right, and right to the first photographing area Ef1. Also, among the first photographing area Ef1 to the ninth photographing area Ef9, photographing areas adjacent to each other above, below, left, and right partially overlap each other.

[0056] Fig. 5 is an explanatory diagram showing a comparative example in which each photographing region of the fundus Ef is photographed in sequence by a conventional method. Note that Fig. 5 and Fig. 6 described later show a simplified illustration of the fundus camera head 16 (fundus photographing section 20 and fixation target presenting section 22). Figs. 5 and 6 also show both the fixation target 23 displayed on the fixation target presenting section 22 and the fixation target 23 presented to the subject's eye E by the fixation target presenting section 22 (i.e., the fixation target 23 projected from the fixation target presenting section 22 onto the fundus Ef). Furthermore, in Figs. 5 and 6, the optical axis of the fundus photographing section 20 is indicated by the symbol OA (see the dashed line in the figure), and the line of sight of the subject's eye E is indicated by the symbol OB (see the dotted line in the figure).

[0057] As shown by reference symbol 5A in Figure 5, in the comparative example, the fixation target control unit 40 sets the display position of the fixation target 23 by the fixation target presenting unit 22 to a display position corresponding to the photographing of the next Mth shooting area EfM (M = any natural number from 1 to 8), and after the subject eye E fixates this fixation target 23, the photographing control unit 46 causes the fundus photographing unit 20 to photograph the Mth shooting area EfM.

[0058] Next, as shown by the reference symbol 5B, the fixation target control unit 40 changes the display position of the fixation target 23 by the fixation target presenting unit 22 to a position corresponding to the photographing of the Nth photographing area EfN (N=M+1). As a result, the subject's eye E fixates the fixation target 23 after the display position is changed, and the subject's eye E rotates according to the change in the line of sight of the subject's eye E, and the Nth photographing area EfN moves into the photographing range of the fundus photographing unit 20. Then, the photographing control unit 46 causes the fundus photographing unit 20 to photograph the Nth photographing area EfN. Hereinafter, in the comparative example, the change in the display position of the fixation target 23 by the fixation target presenting unit 22, the rotation of the subject's eye E, and the photographing by the fundus photographing unit 20 are repeatedly executed until the photographing of the ninth photographing area Ef9 by the fundus photographing unit 20 is completed.

[0059] In the comparative example, the imaging area photographed by the fundus photographing unit 20 is switched by changing the line of sight of the subject's eye E (rotating the subject's eye E) in response to a change in the display position of the fixation target 23 by the fixation target presenting unit 22, but if the subject loses sight of the fixation target 23, it is not possible to photograph the desired imaging area. Therefore, in this embodiment, the imaging area photographed by the fundus photographing unit 20 is switched and the fundus photographing unit 20 photographs each imaging area without changing the line of sight of the subject's eye E.

[0060] Fig. 6 is an explanatory diagram showing a method for photographing each photographing area of ​​the fundus oculi Ef in order in this embodiment. As shown by reference symbol 6A in Fig. 6, first, the fixation target control unit 40 sets the display position of the fixation target 23 by the fixation target presenting unit 22 to a display position corresponding to photographing the first photographing area Ef1, and then causes the subject's eye E to fixate the fixation target 23. After that, the photographing control unit 46 causes the fundus photographing unit 20 to photograph the first photographing area Ef1.

[0061] Next, as shown by reference numerals 6B and 6C in FIG. 6, the fixation target control unit 40 moves the display position of the fixation target 23 on the fixation target presenting unit 22 to a display position corresponding to the shooting of the second shooting area Ef2 (see arrow A1).

[0062] At the same time, the movement control unit 44 drives the swing-tilt drive unit 14b to swing the fundus camera head 16 in a direction (swing direction) and a movement amount (swing angle) that cancels the movement of the display position of the fixation target 23 (see arrow A2). That is, the movement control unit 44 swings the fundus camera head 16 so as to cancel the movement of the display position of the fixation target 23. As described above, the display position of the fixation target 23 for each shooting area by the fixation target presenting unit 22 is predetermined, so the movement direction and movement amount of the fixation target 23 from an arbitrary display position to the next display position are also known. As a result, the swing direction and swing angle of the fundus camera head 16 that cancels the movement of the display position of the fixation target 23 can also be predetermined.

[0063] By swinging the fundus camera head 16 so as to cancel the movement of the display position of the fixation target 23 in this way, the relative position of the fixation target 23 with respect to the subject's eye E is kept constant (including approximately constant, the same applies below) until the display position of the fixation target 23 is moved to a display position corresponding to the photographing of the second photographing area Ef2. As a result, the line of sight of the subject's eye E is kept constant, specifically, it is kept in the direction at the time of photographing the initial first photographing area Ef1. Note that the movement control unit 44 may drive the XYZ drive unit 14a to perform XYZ adjustment of the fundus camera head 16 instead of swinging the fundus camera head 16 so as to cancel the movement of the display position of the fixation target 23, or in addition to swinging the fundus camera head 16.

[0064] Meanwhile, the photographing range of the fundus photographing unit 20 moves within the fundus Ef in response to the swinging of the fundus camera head 16. Therefore, if the movement of the display position of the fixation target 23 and the swinging of the fundus camera head 16 that cancels this movement continue, the fundus photographing unit 20 (photographing range) moves to a photographing position where the second photographing area Ef2 can be photographed. The photographing positions of each photographing area by the fundus photographing unit 20 are also determined in advance for each photographing area. Then, when the fundus photographing unit 20 moves to the photographing position of the second photographing area Ef2, the photographing control unit 46 causes the fundus photographing unit 20 to photograph the second photographing area Ef2.

[0065] Thereafter, until the fundus photographing unit 20 completes photographing the ninth photographing area Ef9, the movement of the display position of the fixation target 23, the swinging of the fundus camera head 16 to cancel out the movement of the fixation target 23, and the fundus photographing by the fundus photographing unit 20 are repeatedly executed. As a result, while the line of sight of the subject's eye E is kept constant, the fundus photographing unit 20 moves in order to photographing positions where the remaining photographing areas (the third photographing area Ef3 to the ninth photographing area Ef9) can be photographed, and photographs of the remaining photographing areas are performed in order.

[0066] The movement of the display position of the fixation target 23, the swinging of the fundus camera head 16, and the fundus photography by the fundus photography unit 20 can be performed automatically. Therefore, photography of each photography area of ​​the fundus Ef in the panoramic photography mode can be automated. In addition, when photographing the fundus, focus adjustment (focus adjustment) is performed by the focus lens included in the photography optical system 21a as necessary.

[0067] In this embodiment, the fundus Ef is divided into nine photographing regions for photographing, but it may be divided into eight or less or ten or more photographing regions for photographing. When the number of photographing regions is increased, the fundus photographing unit 20 continuously photographs (shoots video) the fundus Ef while swinging the fundus camera head 16. The order in which the photographing regions are photographed can also be changed as appropriate.

[0068] 3, the fundus image acquisition unit 48 is connected by wire or wirelessly to the fundus photographing unit 20 via a communication interface (not shown). When photographing the fundus of the subject's eye E (in normal photographing mode and panoramic photographing mode), the fundus image acquisition unit 48 acquires a fundus image D from the fundus photographing unit 20 and stores it in the memory unit 34. As a result, in the panoramic photographing mode, the fundus image acquisition unit 48 acquires and stores in the memory unit 34 a fundus image D of a new photographing area of ​​the fundus Ef every time the fundus photographing unit 20 photographs the fundus image D.

[0069] 7 is an explanatory diagram showing an example of a panoramic image DP generated by the panoramic image generating unit 36. As shown in FIG. 7 and FIG. 3, the panoramic image generating unit 36 ​​corresponds to the wide-area image generating unit of the present invention, and operates in a panoramic photography mode to connect (stitch together) fundus images D of each photographing area of ​​the fundus Ef stored in the storage unit 34 to generate a panoramic image DP, which is a wide-area image of the fundus Ef. Note that a specific method for generating the panoramic image DP is a publicly known technique (see the above-mentioned patent documents), and therefore a detailed description thereof will be omitted here. Then, the panoramic image generating unit 36 ​​stores the panoramic image DP in the storage unit 34 and outputs it to the display control unit 50.

[0070] The display control unit 50 controls the display of the display unit 18. In normal shooting mode, the display control unit 50 causes the display unit 18 to display a fundus image D of an arbitrary photographed area of ​​the fundus Ef photographed by the fundus photographing unit 20. In addition, in panoramic shooting mode, the display control unit 50 causes the display unit 18 to display a panoramic image DP generated by the panoramic image generating unit 36.

[0071] [Function of the Fundus Camera of the First Embodiment] FIG. 8 is a flowchart showing the flow of panoramic photography of the fundus Ef by the fundus camera 10 according to the first embodiment of the control method for an ophthalmologic apparatus of the present invention.

[0072] 8, first, preparations for imaging are performed, such as supporting the subject's face with the face support unit 12 and switching to a panoramic imaging mode with the operation unit 17 (step S1). When this preparation for imaging is completed, the general control unit 32 functions as a fixation target control unit 40, an alignment detection unit 42, a movement control unit 44, an imaging control unit 46, a fundus image acquisition unit 48, and a display control unit 50.

[0073] Next, the fixation target control unit 40 controls the fixation target presenting unit 22 to display (light) the fixation target 23 at a display position corresponding to the photographing of the first photographing area Ef1 of the fundus Ef (step S2). As a result, the fixation target 23 is presented to the subject's eye E, the line of sight of the subject's eye E is fixed in the direction of the fixation target 23, and the first photographing area Ef1 moves into the photographing range of the fundus photographing unit 20.

[0074] Then, the alignment detection unit 42 performs alignment detection based on the anterior eye image acquired from the above-mentioned alignment detection optical system, and based on this alignment detection result, the movement control unit 44 drives the XYZ driving unit 14a to align the fundus camera head 16 with the subject's eye E (step S3). Also, the photography control unit 46 performs focus adjustment of the fundus photography unit 20 with respect to the fundus Ef based on the imaging signal acquired from the focus optical system of the fundus photography unit 20 (step S3).

[0075] When the alignment and focus adjustment are completed, the photography control unit 46 executes photography of the first photography area Ef1 by the fundus photography unit 20 and output of the fundus image D to the fundus image acquisition unit 48 (step S4, which corresponds to the photography step of the present invention). Then, the fundus image acquisition unit 48 stores the fundus image D acquired from the fundus photography unit 20 in the memory unit 34.

[0076] When the photographing of the first photographing area Ef1 is completed, the fixation target control unit 40 controls the fixation target presenting unit 22 to move the display position of the fixation target 23 to a display position corresponding to the photographing of the next second photographing area Ef2 (step S5A). At the same time, as shown in FIG. 6, the movement control unit 44 drives the swing-tilt driving unit 14b in response to the movement of the display position of the fixation target 23, and starts swinging the fundus camera head 16 so as to cancel the movement of the display position of the fixation target 23 (step S5B, which corresponds to the movement control step of the present invention). This keeps the relative position of the fixation target 23 with respect to the subject's eye E constant, so that the line of sight of the subject's eye E is kept constant. As a result, even if the display position of the fixation target 23 is moved, the subject is prevented from losing sight of the fixation target 23.

[0077] When the movement of the display position of the fixation target 23 is completed (step S5C), the swing of the fundus camera head 16 is stopped accordingly (step S5D). As a result, the fundus photographing unit 20 moves to a photographing position where the second photographing area Ef2 can be photographed while keeping the line of sight of the subject's eye E constant.

[0078] Next, similarly to the above-described step S3, alignment of the fundus camera head 16 with respect to the subject's eye E and focus adjustment of the fundus photographing unit 20 with respect to the fundus Ef are performed (step S6).

[0079] Once the alignment and focus adjustment are complete, the photography control unit 46 causes the fundus photography unit 20 to photograph the second photography area Ef2 and output the fundus image D to the fundus image acquisition unit 48, and then the fundus image acquisition unit 48 stores the fundus image D in the memory unit 34 (step S7, which corresponds to the photography step of the present invention).

[0080] Thereafter, the above-mentioned steps S5A to S5D, step S6, and step S7, i.e., the movement of the display position of the fixation target 23, the swinging of the fundus camera head 16 to counter this movement, the photographing of each photographing area by the fundus photographing section 20, and the storage of the fundus image D in the storage section 34 by the fundus image acquisition section 48 are repeatedly executed until fundus photographing of all remaining photographing areas is completed (step S8).Even during this time, the line of sight of the subject's eye E is kept constant, so that the subject is prevented from losing sight of the fixation target 23 even if the display position of the fixation target 23 is moved. When fundus photography of all photographing regions is completed, the panoramic image generating unit 36 ​​generates a panoramic image DP of the fundus Ef based on the fundus images D of the multiple photographing regions of the fundus Ef stored in the storage unit 34, and stores this panoramic image DP in the storage unit 34 (step S9). Then, the display control unit 50 causes the display unit 18 to display the panoramic image DP (step S10).

[0081] As described above, the fundus camera 10 of this embodiment can change the photographing area of ​​the fundus Ef photographed by the fundus photographing unit 20 while keeping the line of sight of the subject's eye E constant by moving the display position of the fixation target 23 and swinging the fundus camera head 16 to cancel the movement of the fixation target 23. This allows photographing of desired photographing areas in the fundus Ef and obtaining good fundus images D of each photographing area without changing the line of sight of the subject's eye E. As a result, a good panoramic image DP is obtained.

[0082] [Second embodiment] 9 is a block diagram showing the configuration of a fundus camera 10 of the second embodiment. The fundus camera 10 of the first embodiment generates and displays a panoramic image DP of the fundus Ef, but an examiner or the like who has an overview of the panoramic image DP may wish to capture a detailed image of a part of the photographed region in the fundus Ef in order to perform a detailed diagnosis of this region.

[0083] 9, the fundus camera 10 of the second embodiment has a special photography mode for photographing a special fundus image DS of a different kind from the normal fundus image D in addition to the normal fundus image D. The fundus camera 10 of the second embodiment photographs a special fundus image DS of a photographing area selected from among the photographing areas of the fundus Ef, and displays the special fundus image DS superimposed on the panoramic image DP.

[0084] The fundus camera 10 of the second embodiment has a fundus photographing unit 20A different from that of the first embodiment, and has some different functions of the fixation target control unit 40, the movement control unit 44, the photographing control unit 46, and the display control unit 50, and has a general control unit 32 functioning as a special fundus image acquisition unit 49. Therefore, the same reference numerals are used to designate the same components as those of the first embodiment in terms of function or configuration, and the description thereof will be omitted.

[0085] The operation unit 17 of the second embodiment accepts a selection operation for selecting one or more photographing areas (hereinafter, referred to as selected photographing areas) in which a special fundus image DS is to be photographed from among the photographing areas.

[0086] The fundus photographing section 20A of the second embodiment has a function of photographing a fundus image D [fundus image photographing optical system], as well as a function of photographing a special fundus image DS of a different kind from the fundus image D [special fundus image photographing optical system]. Examples of the special fundus image DS include an infrared fundus image photographed by using infrared wavelength light to photograph the fundus Ef, a higher resolution fundus image, or a fluorescent image photographed by fluorescently photographing the fundus Ef. In the special photographing mode, the fundus photographing section 20A photographs a special fundus image DS of a selected photographing area selected by a selection operation on the operation section 17.

[0087] In addition, when the fundus photography unit 20A photographs a special fundus image DS, it stores the photography information indicating the selected photography area (photographing position) where the special fundus image DS was photographed in the tag information of the special fundus image DS, etc., and then outputs the special fundus image DS to the special fundus image acquisition unit 49.

[0088] The fixation target control unit 40, movement control unit 44, and photography control unit 46 of the second embodiment function as a special fundus image acquisition control unit of the present invention in special photography mode, and control the photography of a special fundus image DS of the selected photography area by the fundus camera 10.

[0089] In the second embodiment, in the special photography mode, the fixation target control unit 40 controls the fixation target presenting unit 22 to move the fixation target 23 to a display position corresponding to photography of the selected photography area, and presents the fixation target 23 at this display position to the subject's eye E. When there are multiple selected photography areas, the fixation target control unit 40 presents the fixation target 23 to the subject's eye E at each display position in turn by moving the fixation target 23 to a display position corresponding to photography of each selected photography area in turn.

[0090] In the second embodiment, in the special photography mode, the movement control unit 44 drives the electric drive mechanism 14 (the XYZ drive unit 14a and the swing-tilt drive unit 14b) based on the detection result of the alignment detection unit 42 to perform alignment with the subject's eye E. When the special photography mode is executed consecutively from the panoramic photography mode or when multiple photography regions are selected, the movement control unit 44 may maintain the line of sight of the subject's eye E constant by swinging the fundus camera head 16 in the same manner as in the panoramic photography mode.

[0091] In the special photography mode, the photography control unit 46 of the second embodiment adjusts the focus of the fundus photography unit 20A with respect to the fundus Ef, and causes the fundus photography unit 20A to photograph a special fundus image DS of the selected photography area after the completion of the above-mentioned alignment and focus adjustment. When there are multiple selected photography areas, the photography control unit 46 causes the fundus photography unit 20A to photograph a special fundus image DS for each selected photography area in response to the movement of the display position of the fixation target 23, etc.

[0092] The special fundus image acquisition unit 49 operates when the fundus photographing unit 20A photographs a special fundus image DS in the special photographing mode. The special fundus image acquisition unit 49 acquires the special fundus image DS from the fundus photographing unit 20A and stores it in the memory unit 34.

[0093] The display control unit 50 of the second embodiment functions as the first display control unit of the present invention in special shooting mode, and superimposes a special fundus image DS captured by the fundus shooting unit 20A on the panoramic image DP displayed on the display unit 18.

[0094] Fig. 10 is an explanatory diagram showing the panoramic image DP before the special fundus image DS is superimposed and displayed by the display control unit 50. Fig. 11 is an explanatory diagram showing the panoramic image DP after the special fundus image DS is superimposed and displayed by the display control unit 50.

[0095] As shown in Fig. 10, in the special photography mode, the display control unit 50 reads out the panoramic image DP and the special fundus image DS from the storage unit 34, and determines the selected photography area (here, the eighth photography area Ef8) in which the special fundus image DS was photographed based on the photography information stored in the tag information of the special fundus image DS. Here, the position, range, and shape of the fundus image D of each photography area in the panoramic image DP are known. Therefore, as shown in Fig. 11, the display control unit 50 causes the display unit 18 to display the panoramic image DP, and causes the special fundus image DS to be superimposed on the fundus image D corresponding to the selected photography area in the panoramic image DP.

[0096] 12 is a flow chart showing the flow of the photographing process of the special fundus image DS by the fundus camera 10 of the second embodiment and the process of superimposing the special fundus image DS on the panoramic image DP. Note that the process up to step S10 is the same as that of the first embodiment shown in FIG. 8, so a detailed description is omitted here.

[0097] As shown in FIG. 12, when the panoramic image DP is displayed on the display unit 18 in step S10, the examiner looks down on the entire image and, if there is a selected observation area that requires capturing a special fundus image DS, operates the operation unit 17 etc. to switch the operating mode of the fundus camera 10 to special photography mode and selects the selected photography area (step S11).

[0098] Next, the fixation target control unit 40 controls the fixation target presenting unit 22 to move the display position of the fixation target 23, or the movement control unit 44 drives the electric drive mechanism 14 to move (move and swing in the XYZ directions) the fundus camera head 16, or both are performed so that the selected shooting area in the fundus Ef moves within the shooting range of the fundus photography unit 20A (step S12).

[0099] Then, similarly to the above-described steps S3 and S6, alignment of the fundus camera head 16 with respect to the subject's eye E and focus adjustment of the fundus photographing section 20 with respect to the fundus Ef are performed (step S13).

[0100] When the alignment and focus adjustment are completed, the photography control unit 46 executes the photography of the special fundus image DS of the selected photography area by the fundus photography unit 20A and the output of the special fundus image DS to the special fundus image acquisition unit 49 (step S14). Next, the acquisition of the special fundus image DS by the special fundus image acquisition unit 49 and storage in the memory unit 34 are executed.

[0101] If there are a plurality of selected photographing regions, the above-mentioned processes of steps S12 to S14 are repeatedly executed, and special fundus images DS of the remaining selected photographing regions are photographed and stored in the storage unit 34 (NO in step S15).

[0102] When the photographing of the special fundus images DS of all the selected photographing areas and the storage in the memory unit 34 are completed (YES in step S15), the display control unit 50 reads out the panoramic image DP and the special fundus image DS from the memory unit 34. Then, the display control unit 50 causes the display unit 18 to display the panoramic image DP as shown in Figs. 10 and 11, and causes the special fundus image DS to be superimposed on the fundus image D corresponding to the selected photographing area in the panoramic image DP (step S16).

[0103] As described above, in the second embodiment, by superimposing a special fundus image DS on a selected shooting area within the panoramic image DP displayed on the display unit 18, it is possible to obtain an overview of the entire fundus Ef based on the panoramic image DP, while diagnosing in detail the selected shooting area within the fundus Ef based on the special fundus image DS.

[0104] [Third embodiment] 13 is a block diagram showing the configuration of a fundus camera 10 of the third embodiment. In each of the above embodiments, a panoramic image DP is generated and displayed after the entire photographing area of ​​the fundus Ef is photographed. In contrast, the fundus camera 10 of the third embodiment repeatedly executes a process of linking (splicing) the new fundus image D to the previously photographed fundus image D and a process of displaying the newly joined fundus image D on the display unit 18 every time a fundus image D of a new photographing area is photographed. Note that the "previously photographed fundus image D" is not limited to the fundus image D photographed immediately before the new fundus image D, and may be a plurality of images.

[0105] 13, the fundus camera 10 of the third embodiment has basically the same configuration as the fundus camera 10 of each of the above-mentioned embodiments, except for some differences in the functions of the panoramic image generating unit 36 ​​and the display control unit 50. For this reason, the same reference numerals are used to designate the same components in function or configuration as those of the above-mentioned embodiments, and the description thereof will be omitted.

[0106] The panoramic image generating unit 36 ​​of the third embodiment is provided with an image processing unit 36a. Every time a fundus image D of a new photographing area is photographed by the fundus photographing unit 20 (or the fundus photographing unit 20A), that is, every time a fundus image D of a new photographing area is stored in the storage unit 34, the image processing unit 36a generates a connected image DPa by connecting the new fundus image D to the fundus image D photographed earlier. When the image processing unit 36a completes the connection of the fundus image D of the last photographing area, a panoramic image DP is generated (see FIG. 16).

[0107] The display control unit 50 of the third embodiment functions as a second display control unit of the present invention in the panoramic photography mode. The display control unit 50 causes the display unit 18 to start displaying a new fundus image D (connected image DPa) every time the image processing unit 36a performs a connection process for a new fundus image D, i.e., every time a new connected image DPa is generated (see Figs. 14 to 16 described later).

[0108] Fig. 14 is a time chart showing an example of the timing of photographing a fundus image D by the fundus photographing unit 20, the process of connecting the fundus images D by the image processing unit 36a, and the process of displaying a new fundus image D (connected image DPa) by the display unit 18. Note that "Fundus image 1", "Fundus image 2", "Fundus image 3", etc. in Fig. 14 indicate fundus images D photographed in the first photographing area Ef1, the second photographing area Ef2, the third photographing area Ef3, etc., respectively.

[0109] 15 and 16 are explanatory diagrams showing specific examples of a new fundus image D (connected image DPa) displayed on the display unit 18. In FIG.

[0110] 14 to 16, in the third embodiment, as shown in steps S1 to S7 in Fig. 8, the fundus photographing section 20 photographs the fundus image D in the first photographing area Ef1 and the second photographing area Ef2 in order. In the third embodiment, when the fundus image D in the second photographing area Ef2 is photographed, the display control section 50 starts displaying the fundus image D in the first photographing area Ef1 on the display section 18 (see reference numeral 150A in Fig. 15).

[0111] Next, the processes of step S8, steps S5A to S5D, step S6, and step S7 shown in Fig. 8 are repeatedly executed, and the fundus photographing section 20 starts photographing the third photographing area Ef3. During photographing of the third photographing area Ef3, the image processing section 36a performs a process of connecting the fundus image D of the second photographing area Ef2 to the fundus image D of the first photographing area Ef1. When this connecting process is completed, the display control section 50 starts displaying the fundus image D of the second photographing area Ef2 on the display section 18, that is, displaying a connected image DPa of both fundus images D (see reference numeral 150B in Fig. 15).

[0112] Then, the processes of step S8, steps S5A to S5D, step S6, and step S7 shown in Fig. 8 are repeated again, and the fundus photographing section 20 starts photographing the fourth photographing area Ef4. During photographing of the fourth photographing area Ef4, the image processing section 36a performs a process of connecting the fundus image D of the third photographing area Ef3 to the fundus image D of the second photographing area Ef2 (or the fundus image D of the first photographing area Ef1). When this connecting process is completed, the display control section 50 starts displaying the fundus image D of the third photographing area Ef3 (connected image DPa) on the display section 18 (see reference numeral 150C in Fig. 15).

[0113] Thereafter, when the fundus photographing section 20 photographs each photographing area after the fifth photographing area Ef5, a process of connecting the fundus images D photographed in the previous photographing area and a process of displaying the newly connected fundus image D (connected image DPa) are repeatedly executed (see reference numerals 150D and 150E in FIG. 16). After the fundus photographing section 20 photographs the ninth photographing area Ef9, a process of connecting the fundus images D of the ninth photographing area Ef9 is executed, thereby completing the generation of a panoramic image DP, and the panoramic image DP is displayed on the display section 18 (see reference numeral 150F in FIG. 16).

[0114] As described above, in the third embodiment, each time a fundus image D of a new photographing area is photographed, the process of connecting the new fundus image D to the previously photographed fundus image D and the process of causing the display unit 18 to start displaying the newly connected fundus image D are repeatedly executed, thereby making it possible to display the process of generating the panoramic image DP in real time. As a result, fundus images D of a plurality of photographing areas (connected image DPa) can be observed in real time during the panoramic photographing mode.

[0115] [Fourth embodiment] 17 is a block diagram showing the configuration of the fundus camera 10 of the fourth embodiment. In each of the above embodiments, the fundus image D of each photographing area and the panoramic image DP are stored in the storage unit 34, but the panoramic image DP has a large amount of data, which puts a strain on the storage capacity of the storage unit 34. For this reason, it is possible to generate the panoramic image DP by the panoramic image generating unit 36 ​​when confirmation (display) of the panoramic image DP is required, without storing the panoramic image DP in the storage unit 34, but in this case, it takes time to generate the panoramic image DP. As a result, a problem occurs in that it takes a long time to complete the display of the panoramic image DP.

[0116] Therefore, the fundus camera 10 of the fourth embodiment makes it possible to easily (in a short time) generate a panoramic image DP from the fundus image D of each photographed area of ​​the fundus Ef, instead of storing the panoramic image DP generated by the panoramic image generation unit 36 ​​in the memory unit 34.

[0117] 17, the fundus camera 10 of the fourth embodiment has basically the same configuration as the fundus camera 10 of each of the above-mentioned embodiments, except that an information generating unit 37 is connected to the general control unit 32. Therefore, the same reference numerals are used to designate the same components as those of the above-mentioned embodiments in terms of function or configuration, and the description thereof will be omitted.

[0118] Based on the fundus images D of each photographing area stored in the storage unit 34, the information generation unit 37 generates image generation information 37a for the panoramic image generation unit 36 ​​to generate a panoramic image DP from each fundus image D, and stores the image generation information 37a in the storage unit 34. This image generation information 37a includes, for example, position information of the fundus images D of each photographing area in the panoramic image DP, and overlapping area information indicating the position, size, and shape of overlapping areas between adjacent fundus images D.

[0119] The panoramic image generator 36 of the fourth embodiment generates a panoramic image DP from the fundus image D of each shooting area in the storage unit 34 and image generation information 37a in response to a panoramic image display operation on the operation unit 17. By generating the panoramic image DP based on the image generation information 37a in this manner, it is possible to generate the panoramic image DP in a shorter time than when generating the panoramic image DP from scratch. Then, the display control unit 50 causes the display unit 18 to display the panoramic image DP generated by the panoramic image generator 36.

[0120] As described above, in the fourth embodiment, instead of storing the panoramic image DP in the memory unit 34, the image generation information 37a used to generate the panoramic image DP is stored in the memory unit 34, so that the panoramic image DP can be generated in a short period of time and displayed on the display unit 18 while suppressing an increase in the storage capacity of the memory unit 34.

[0121] In the fourth embodiment, the information generating section 37 is provided separately from the panoramic image generating section 36. However, the panoramic image generating section 36 may function as the information generating section 37.

[0122] [Fifth embodiment] FIG. 18 is a block diagram showing the configuration of the fundus camera 10 of the fifth embodiment. In each of the above embodiments, in the panoramic photography mode, each photographing area of ​​the fundus Ef is photographed in order, and each photographing area is photographed through the pupil of the subject's eye E. At this time, if the fundus camera 10 is a non-mydriatic fundus camera, the size of the pupil diameter of the subject's eye E changes, and the amount of illumination light irradiated from the fundus photographing unit 20 to the fundus Ef also changes according to the change in the pupil diameter. As a result, the amount of illumination light irradiated from the fundus photographing unit 20 changes for each photographing area, and the brightness of the fundus image D for each photographing area differs. In this case, the brightness of the panoramic image DP becomes uneven, and the image quality of the panoramic image DP decreases.

[0123] Therefore, the fundus camera 10 of the fifth embodiment performs exposure control during shooting of each shooting region so that the brightness of the fundus image D for each shooting region becomes uniform. As shown in Fig. 18, the fundus camera 10 of the fifth embodiment has basically the same configuration as the fundus camera 10 of each of the above embodiments, except that it includes an anterior eye camera 100 and the general control unit 32 also functions as an anterior eye image acquisition unit 60, a pupil diameter detection unit 62, and an exposure control unit 64. Therefore, the same reference numerals are used for components that are the same in function or configuration as those of the above embodiments, and their description will be omitted.

[0124] The anterior eye camera 100 corresponds to the anterior eye photographing unit of the present invention, and is, for example, a monocular camera or a stereo camera provided on the fundus camera head 16. The anterior eye camera 100 continuously photographs (takes moving images of) the anterior eye Ea of the subject's eye E at least in the panoramic photography mode, and continuously outputs anterior eye images DF of the anterior eye Ea to the anterior eye image acquiring unit 60. Instead of using the anterior eye camera 100, the anterior eye image DF may be acquired using the anterior eye photographing function of the fundus photography unit 20.

[0125] The anterior eye image acquisition unit 60 is wired or wirelessly connected to the anterior eye camera 100 via a communication interface not shown, and continuously acquires anterior eye images DF from the anterior eye camera 100 during panoramic shooting mode and continuously outputs them to the pupil diameter detection unit 62.

[0126] In the panoramic photography mode, the pupil diameter detection unit 62 detects the pupil diameter of the subject's eye E from a new anterior eye image DF every time the anterior eye image DF is input from the anterior eye image acquisition unit 60. For example, the pupil diameter detection unit 62 detects the pupil edge based on the difference in brightness between the pupil and the iris in the anterior eye image DF, and detects the pupil diameter by calculating an elliptical approximation of the pupil edge and the center coordinates. This makes it possible to detect the pupil diameter of the subject's eye E in real time in the panoramic photography mode. The pupil diameter detection unit 62 then sequentially outputs the detection results of the pupil diameter of the subject's eye E to the exposure control unit 64.

[0127] The exposure control unit 64 performs exposure control to adjust the brightness of the fundus image D captured by the fundus photographing unit 20, for example, by adjusting the aperture diameter of an aperture (not shown) of the fundus photographing unit 20 or adjusting the sensitivity and shutter speed of the image sensor 21b. Based on the detection result of the pupil diameter of the subject's eye E sequentially input from the pupil diameter detection unit 62, the exposure control unit 64 performs exposure control of the fundus photographing unit 20 when photographing each photographing area so that the brightness of the fundus image D captured by the fundus photographing unit 20 for each photographing area becomes uniform (including approximately uniform).

[0128] Fig. 19 is a flow chart showing the flow of panoramic photography of the fundus Ef by the fundus camera 10 of the fifth embodiment. As shown in Fig. 19, after the processing of steps S1 and S2 or simultaneously with the processing of steps S1 and S2, the anterior eye camera 100 starts continuous photography (video photography) of the anterior eye Ea and continuously outputs the anterior eye images DF to the anterior eye image acquisition unit 60 (step S2A). As a result, the anterior eye image acquisition unit 60 continuously acquires the anterior eye images DF from the anterior eye camera 100 and continuously outputs them to the pupil diameter detection unit 62.

[0129] Next, the pupil diameter detection unit 62 repeatedly executes a detection process to detect the pupil diameter of the test eye E based on the anterior eye image DF each time the anterior eye image DF is input from the anterior eye image acquisition unit 60, and sequentially outputs the pupil diameter detection results to the exposure control unit 64 (step S2B).

[0130] Then, after the alignment and focus adjustment in the above-mentioned step S3 (which may be performed before or simultaneously with step S3), the exposure control unit 64 performs exposure control of the fundus photographing unit 20 based on the detection result of the pupil diameter of the subject's eye E sequentially input from the pupil diameter detection unit 62 (step S3A). After this exposure control, in the above-mentioned step S4, the fundus photographing unit 20 photographs the first photographing area Ef1.

[0131] After fundus photography in step S4, the processes in steps S5A to S5D and step S6 described above are performed, and then the exposure control unit 64 again controls the exposure of the fundus photography unit 20 based on the detection results of the pupil diameter of the subject's eye E sequentially input from the pupil diameter detection unit 62 (step S6A). After this exposure control, in step S7 described above, the fundus photography unit 20 photographs the second photography area Ef2.

[0132] Thereafter, the above-mentioned processes of steps S5A to S5D, step S6, step S6A, and step S7 are repeatedly executed until fundus photography of all remaining photographing areas is completed (step S8). Note that the processes from step S9 onwards are the same as those in the first embodiment shown in FIG. 8, and therefore detailed explanations will be omitted.

[0133] As described above, in the fifth embodiment, before photographing each photographing area of ​​the fundus Ef, the brightness of the fundus image D for each photographing area can be made uniform by controlling the exposure of the fundus photographing unit 20 based on the detection result of the pupil diameter of the subject's eye E. As a result, the brightness of the panoramic image DP can be made uniform, thereby improving the image quality of the panoramic image DP.

[0134] [others] In each of the above embodiments, the panoramic image DP is generated based on the fundus image D (front image) of each photographing region of the subject's eye E, but the type of fundus image D for generating the panoramic image DP is not particularly limited. For example, the special fundus image DS described in the above second embodiment may be photographed in each photographing region, and the panoramic image DP may be generated based on the special fundus image DS of each photographing region. Also, an OCT (Optical Coherence Tomography) image of the fundus Ef may be photographed in each photographing region, and the panoramic image DP (3D wide-area image of the fundus Ef) may be generated based on the OCT image of each photographing region. In this case, the present invention is applicable to a multifunction device that combines a fundus camera 10 and an optical coherence tomograph that obtains OCT images.

[0135] In each of the above embodiments, the fundus photography unit 20 is moved relative to the test eye E by driving the electric drive mechanism 14 to move the fundus camera head 16, but the fundus photography unit 20 may also be moved relative to the test eye E by, for example, moving the subject (the subject's chair, face support unit 12, etc.) while keeping the fundus camera head 16 stationary.

[0136] In each of the above embodiments, the fundus camera 10 is provided with the panoramic image generating unit 36, but the panoramic image generating unit 36 ​​may be provided separately from the fundus camera 10. In other words, the present invention is also applicable to a fundus camera 10 (ophthalmic device) that only captures images of each capture area of ​​the fundus Ef.

[0137] In the above-mentioned embodiments, the fundus camera 10 for photographing the fundus of the subject's eye E has been described as an example, but the present invention can be applied to various ophthalmic devices for photographing the fundus, such as the above-mentioned multifunction machines. The present invention can also be applied to various ophthalmic devices for photographing one or more desired photographing areas in the fundus Ef by internal fixation. [Explanation of symbols]

[0138] 10 Fundus Camera 10a Camera body 11. Base 12 Face support 12a Chin rest 12b Forehead protector 14 Electric drive mechanism 14a XYZ drive unit 14b Swing-tilt drive unit 15 External Fixation Light 16 Fundus camera head 16a Objective lens 16b Eyepiece 17 Control section 17a Operating lever 17b Input Devices 18 Display 20 Fundus Photography Section 20A Fundus photography unit 21a Shooting optical system 21b Image sensor 22 Fixation target presentation part 23 Fixation target 30 Control device 32 General Control Unit 34 Storage section 36 Panorama image generator 36a Image processing section 37 Information generation section 37a Image Generation Information 40 Fixation target control unit 42 Alignment detection unit 44 Movement control section 46 Shooting control section 48 Fundus image acquisition unit 49 Special fundus image acquisition unit 50 Display control unit 60 Anterior segment image acquisition unit 62 Pupil diameter detection unit 64 Exposure control section 100 Anterior Eye Camera D fundus image DF anterior segment image DP Panorama Image DPa Connected Images DS special fundus image E. Examined eye Ea anterior segment Ef fundus Ef1~Ef9 1st shooting area~9th shooting area

Claims

1. a fundus photographing unit for photographing a fundus of a subject's eye; a relative movement unit that moves the fundus photography unit relative to the subject's eye; a fixation target presenting unit that is provided movably together with the fundus photographing unit and presents a fixation target to the subject's eye and is capable of moving the fixation target; a movement control unit that drives the relative movement unit in response to movement of the fixation target by the fixation target presenting unit to relatively move the fundus imaging unit in a direction and by an amount of movement that cancels the movement of the fixation target; Equipped with the fundus photographing unit photographs the fundus at a plurality of photographing positions in accordance with the relative movement by the movement control unit, and obtains fundus images of a plurality of photographing regions within the fundus; the fundus photographing unit has a function of photographing a special fundus image different from the fundus image; a wide-area image generating unit that generates a wide-area image of the fundus based on the fundus image for each of the photographing regions photographed by the fundus photographing unit; a display unit that displays the wide area image generated by the wide area image generating unit; an operation unit for performing a selection operation to select a selected photographing area, which is the photographing area in which the special fundus image is to be photographed, from among the plurality of photographing areas; a special fundus image acquisition control unit that controls the fixation target presenting unit, the relative movement unit, and the fundus photographing unit based on the selection operation on the operation unit to acquire the special fundus image of the selected photographing area; a first display control unit that displays the special fundus image in a superimposed manner on the fundus image corresponding to the selected photographing area in the wide-area image displayed on the display unit; An ophthalmic apparatus comprising:

2. the fixation target presenting unit sequentially moves the fixation target to a plurality of positions; The ophthalmologic apparatus according to claim 1 , wherein the movement control unit moves the fundus photography unit relatively and the fundus photography unit photographs a new photographing area in response to movement of the fixation target by the fixation target presenting unit.

3. the wide-area image generating unit links the new fundus image to the fundus image captured by the fundus photographing unit prior to the new fundus image, each time the new fundus image is captured by the fundus photographing unit; The ophthalmologic apparatus according to claim 1 , further comprising a second display control unit that causes the display unit to start displaying the newly connected fundus image each time the wide area image generating unit connects the fundus images.

4. an information generating unit that generates image generation information for generating the wide-area image from the fundus image for each of the photographing regions by the wide-area image generating unit; a storage unit that stores the fundus image for each of the photographing regions and the image generation information generated by the information generation unit; Equipped with An ophthalmologic device according to any one of claims 1 to 3, wherein the wide-area image generation unit generates the wide-area image based on the fundus image and the image generation information for each shooting area in the memory unit in response to a display operation of the wide-area image.

5. an anterior segment photographing unit that continuously photographs an anterior segment of the subject's eye; a pupil diameter detection unit that detects a pupil diameter of the subject's eye based on an anterior-segment image captured by the anterior-segment imaging unit every time the anterior-segment imaging unit captures an image of the anterior eye; an exposure control unit that controls exposure of the fundus photographing unit based on a detection result of the pupil diameter detection unit and makes the brightness of the fundus image uniform for each photographing area; The ophthalmic apparatus according to claim 1 , further comprising:

6. A control method for an ophthalmologic apparatus including a fundus photographing unit that photographs a fundus of a subject's eye, a relative movement unit that moves the fundus photographing unit relative to the subject's eye, and a fixation target presenting unit that is provided so as to be movable integrally with the fundus photographing unit and presents a fixation target to the subject's eye and is capable of moving the fixation target, a movement control step of driving the relative movement unit in response to the movement of the fixation target by the fixation target presenting unit to relatively move the fundus imaging unit in a direction and by an amount of movement that cancels the movement of the fixation target; an imaging step of performing imaging of the fundus by the fundus imaging unit at a plurality of imaging positions in accordance with the relative movement of the fundus imaging unit in the movement control step, thereby acquiring fundus images of a plurality of imaging regions in the fundus; a wide-area image generating step of generating a wide-area image of the fundus based on the fundus image for each of the photographing regions photographed by the fundus photographing unit; a display step of displaying the wide area image generated in the wide area image generating step on a display unit; an operation step in which the fundus photographing unit, which has a function of photographing a special fundus image different from the fundus image, performs a selection operation to select a selected photographing area, which is the photographing area in which the special fundus image is to be photographed, from among the plurality of photographing areas; a special fundus image acquisition control step of controlling the fixation target presenting unit, the relative movement unit, and the fundus photographing unit based on the selection operation in the operation step to acquire the special fundus image of the selected photographing area; a display control step of superimposing the special fundus image on the fundus image corresponding to the selected photographing area in the wide-area image displayed on the display unit; A method for controlling an ophthalmic apparatus having the above-mentioned features.

Images