JP6460650B2 - Ophthalmic equipment - Google Patents

Description

  The present invention relates to a scanning laser ophthalmoscope (SLO) having an enlarged display function.

  A scanning laser ophthalmoscope (SLO) is known as an ophthalmologic apparatus used for diagnosing an eye disease or the like (see, for example, Patent Document 1). A scanning laser ophthalmoscope (SLO) is an apparatus that observes the state of the fundus (retina) seen from the front by irradiating the fundus while scanning with laser light and detecting reflected light from the fundus.

  The scanning laser ophthalmoscope irradiates the fundus while scanning (scanning) measurement light, detects the reflected light as detection light, and obtains an image of the fundus from the detection light. The scanning of the measurement light is performed by combining high-speed vertical (or horizontal) scanning and low-speed horizontal (or vertical) scanning. Here, in high-speed scanning, a resonant scanner is used to obtain required characteristics. The resonant scanner uses a resonance phenomenon to reciprocate a mirror, thereby scanning reflected light. Here, when the vertical direction of scanning corresponds to, for example, the fundus vertical direction, the horizontal direction of scanning corresponds to the horizontal direction of the fundus.

Special table 2013-517842 gazette

  By the way, although the resonant scanner can operate at high speed, the scanning center (scanning center) cannot be changed (or is difficult to change). For this reason, when observing with a part of the image magnified, the line of sight of the eye to be examined is moved so that the point of interest is at the center of the scan, and then scanning is performed again. The operation of moving the line of sight of the subject's eye is very troublesome for the subject, and there is a problem that the user (operator of the ophthalmologic apparatus) may lose sight of the point of interest (the portion to be enlarged) during the operation. It was.

  In such a background, the present invention can perform partial enlarged display of an arbitrary portion in the visual field with less burden on the subject in observation of the fundus using a scanning laser ophthalmoscope (SLO). The purpose is to provide technology.

According to the first aspect of the present invention, there is provided a measurement light irradiator that irradiates the fundus with measurement light, a first scanner that performs relatively high-speed scanning of the measurement light in a first direction, and the first direction. The measurement light can be scanned at a relatively low speed in the direction orthogonal to the first scanning direction, the scanning range of the first scanner can be moved in the direction orthogonal to the first, and the scanning center can be changed. 2 scanner, a third scanner capable of moving the scanning range of the first scanner in the first direction, and capable of changing the scanning center, the first scanner, the second scanner A scanner control unit that controls the scanner and the third scanner, a reflected light detection unit that detects reflected light from the fundus of the measurement light, and a fundus image creation that creates a fundus image of the fundus based on the reflected light And the fundus image A designation accepting unit for accepting specification of a specific portion of the inner, and a fixation target is a visual target for fixing the orientation or line of sight of the eye, the scanner control unit, of the first scanner to the specific portion Controlling the second and third scanners so that the scanning center is located, changing the position of the scanning center of the first scanner, and controlling the first scanner by the second and third scanners. There line and a scan control of the first scanner and the second scanner by narrowing the scanning range after a change of the position of the scanning center is performed, the fixation target is the subject's eye by moving orientation or An ophthalmic apparatus characterized by guiding a line of sight in a direction intended by a user .

According to a second aspect of the present invention, in the first aspect of the present invention, the fixed index is movable in a direction perpendicular to the optical axis of the measurement light .

According to a third aspect of the present invention, in the first or second aspect of the present invention, the solid index is composed of a film that emits visible light or an organic EL element .

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the scanner control unit includes a variable angle range of a reflecting mirror of the first scanner and a scan range in the fundus image. The relationship between the scanner center of the second scanner and the coordinates of the fundus image, the relationship between the variable angle range of the second scanner and the scan range in the fundus image, and the scanner of the third scanner Based on the relationship between the center and the coordinates of the fundus image, and the relationship between the variable angle range of the third scanner and the scan range in the fundus image, the first scanner, the second scanner, and the third The scanner is controlled .

  According to the present invention, in the observation of the fundus using a scanning laser ophthalmoscope, it is possible to obtain a technique capable of performing partial enlarged display of an arbitrary portion in the visual field with less burden on the subject.

It is a conceptual diagram of the optical system of embodiment. It is a conceptual diagram which shows the method of a scan It is a block diagram of a control system. It is a flowchart which shows an example of the procedure of a process. It is a drawing substitute photograph which shows an example of an observation image. It is a drawing substitute photograph which shows an example of an observation image. It is a drawing substitute photograph which shows an example of an observation image. It is a drawing substitute photograph which shows an example of an observation image.

(Constitution)
FIG. 1 shows an ophthalmic apparatus 100 according to an embodiment. The ophthalmologic apparatus 100 is an adaptive optical scanning laser ophthalmoscope (AO-SLO). The ophthalmic apparatus 100 includes a light source 101. For example, a light source 101 that emits light having high directivity selected from a wavelength range of 500 nm to 1500 nm, that is, light having a small divergence angle is used. Examples of the light source 101 include a solid-state laser, a gas laser, a laser diode (LD), a super luminescent diode (SLD), and a laser driven light source (LDLS).

  An optical fiber 102 that guides light is connected to the light source 101. A single mode optical fiber is employed as the optical fiber 102. A lens (collimator lens) 103 for collimating the laser light emitted from the optical fiber 102 is disposed at the tip of the optical fiber 102. The light from the light source 101 is converted into parallel light by the lens 103 and enters the half mirror 104. The half mirror 104 is a light quantity splitting mirror that branches the light projecting system and the wavefront detecting system. Here, the light projecting system is an optical system that irradiates light to the eye 300, and parallel light obtained by the configuration of the light source 101, the optical fiber 102, and the lens 103 is converted into relay lenses 115, 116, 118, and 119. , 121, 122, 124, and 128, and refers to the entire optical system that emits a light beam that matches the diopter of the eye to be examined from the objective lens 131. The wavefront detection system is an optical system for detecting wavefront information from reflected light (detection light) from the fundus 301 of the eye 300 to be examined, and includes a wavefront detection unit 105 and an optical system 109.

  The half mirror 104 transmits part of the laser light (projection) from the light source 101 to the half mirror 110 side described later, and part of detection light incident from the half mirror 110 side of the wavefront detection unit 105. Reflect to the side. Note that the branching ratio (the ratio of the amount of light to be divided) of the half mirror 104 is not limited to 1: 1, and can be arbitrarily set as necessary. It is also possible to use a polarization beam splitter instead of the half mirror 104.

  The wavefront detection unit 105 includes a CCD 107 that is an imaging device and a lens array 106 in front of the CCD 107. The lens array 106 is a Hartmann plate, and the wavefront detection unit 105 functions as a Shack-Hartmann sensor. The lens array 106 is an array of small lenses arranged in a grid, and divides incident light into a number of light beams and condenses them. The light condensed by the lens array 106 is imaged by the CCD 107, and the wavefront aberration of the light incident on the lens array 106 can be known by analyzing the focal position of each lens.

  An image picked up by the CCD 107 is sent to a calculation unit 203 described later. The arithmetic unit 203 analyzes the wavefront disturbance of the fundus 301 based on the image captured by the CCD 107, and further controls the wavefront correction device based on the result of the analysis.

  An optical system 109 having a pair of lenses and a pinhole (optical aperture) between them is disposed between the half mirror 104 and the wavefront detection unit 105. The position in the depth direction of the reflected light beam from the fundus 301 detected by the wavefront detection unit 105 can be limited by the optical system 109. Further, the optical system 109 reduces reflection noise from the optical system and the eye 300 to be examined.

  Another half mirror 110 is arranged on the eye 300 side of the half mirror 104. The half mirror 110 is a light quantity splitting mirror that branches the light projecting system and the retinal imaging system (fundus imaging system). The retinal imaging system detects image information of the retina on the fundus 301 from the reflected light (detection light) from the fundus 301.

  The retinal imaging system includes a lens 111, a pinhole (optical aperture) 112, and a fundus reflection light detector 113. The fundus reflection light detector 113 is a light detection element that detects weak reflected light from the fundus 301, and includes, for example, an APD (avalanche photodiode) or a photomultiplier tube. A detection signal from the fundus reflection light detector 113 is sent to the arithmetic unit 203 via an ADC (A / D converter) 202 described later. By irradiating the fundus 301 with light from the light source 101 while scanning, the fundus reflection light detector 113 obtains scan data of reflected light.

  A pinhole 112 that functions as an optical aperture is disposed in front of the fundus reflection light detector 113, and a light beam is emitted in front of the pinhole 112 so that the fundus conjugate position is located at the optical aperture of the pinhole 112. A lens 111 for squeezing is disposed.

  A first scanner 114, a second scanner 120, and a third scanner 123 constituting a scanning system are arranged on the eye 300 side of the half mirror 110. Each scanner is disposed at a pupil conjugate position. The first scanner 114 performs scanning in the vertical direction (vertical direction). This scan is performed at a higher speed than the second scanner and the third scanner. The first scanner 114 is constituted by a resonant scanner. The resonant scanner 114 (resonance type scanner) is an optical element that scans reflected light by rotating a mirror back and forth by a resonance motion. Resonant scanners cannot move the scan center, but have the advantage of being able to scan at high speed.

  The second scanner 120 is used for scanning in the horizontal direction (left-right direction), but is also used for moving the scan center of the first scanner 114 in the horizontal direction. The second scanner 120 is configured by a galvano scanner. The galvano scanner has a structure in which a mirror attached to a rotating shaft is driven by a motor. The galvano scanner cannot operate at a higher speed than the resonant scanner, but can set the scan center to a desired position.

  The third scanner 123 is used to move the scan center of the first scanner 114 in the vertical direction, and the third scanner 123 scans at a lower speed than the first scanner 114. The third scanner 123 does not require high-speed scanning like the first scanner 114, but a galvano scanner is used because control of the scan position is necessary. Reference numerals 115, 116, 118, 119, 121, 122, and 124 are relay lenses that form an optical path. The operation of each scanner will be described later.

  A deformable mirror 117 that is a wavefront correction device is disposed between the first scanner 114 and the second scanner 120. The deformable mirror 117 is a deformable mirror for performing wavefront correction. The deformable mirror 117 is a mirror whose surface shape can be deformed by a plurality of actuators. The deformable mirror 117 is controlled by the calculation unit 206, and corrects the wavefront of the reflected light by deforming the reflecting surface. As the wavefront correction device, a spatial phase modulator, a bimorph mirror, or the like can be used.

  A diopter correction system 125 is provided on the eye side 300 of the relay lens 124. The diopter correction mechanism 125 performs adjustment so that the observation point of the fundus 301 is the focal point of the optical system. That is, the diopter correction mechanism 125 performs adjustment so that the laser light is irradiated onto the fundus 301 as a substantially point image. The diopter correction mechanism 125 includes diopter-shaped diopter correction mirrors 126 and 127.

  Adjustment is performed so that the fundus 301 is focused by moving the diopter correction mirror 126 relative to the diopter correction mirror 127. There are individual differences and individual differences in diopter. Even if there is a difference in diopter, by moving the position of the diopter correction mirror 126, the fundus 301 is focused, that is, on the fundus 301. Adjustment is performed so that the irradiation light is condensed and irradiated as a substantially point image. Further, the diopter correction mechanism 125 performs fine adjustment of the light collection position on a specific layer to be observed.

  Dichroic mirrors 129 and 130 are arranged on the side of the eye 300 to be examined of the diopter correction mechanism 125 via the lens system 128. The dichroic mirror 129 reflects light from the light source 101 and transmits near-infrared light that is illuminated from a near-infrared light source (not shown) and reflected from the anterior segment. For example, the dichroic mirror 129 reflects light having a wavelength of 840 nm from the light source 101 and transmits light having a wavelength of 950 nm that is illuminated by a near-infrared light source (not shown) and reflected from the anterior segment.

  The dichroic mirror 130 reflects near-infrared light that is irradiated on the anterior eye part from the light source 101 and a light source (not shown) and reflected on the anterior eye part, and transmits light from a fixation target 132 described later. For example, the dichroic mirror 130 reflects light having a wavelength of 840 nm from the light source 101 and light having a wavelength of 950 nm reflected by the anterior eye portion, and transmits light having a wavelength of 550 nm from the fixation target 132 described later.

  An objective lens 131 is disposed in front of the eye 300 to be examined. The objective lens 131 has a structure in which a plurality of lenses are combined in order to suppress aberrations (of course, it may be composed of a single lens). The objective lens 131 is set so that the pupil of the optical system matches the pupil position of the eye 300 to be examined.

  The eye 300 visually recognizes the fixation target 132 through the dichroic mirror 130. The fixation target 132 is a visual target for fixing the direction (line of sight) of the eye 300 to be examined. The fixation target 132 is composed of a film or an organic EL element that emits light having a wavelength that can be visually recognized by the eye 300 (about 400 nm to 600 nm), and is movable in a direction perpendicular to the optical axis. By moving the fixation target 132, the direction of the line of sight of the eye 300 to be examined can be guided in the direction intended by the observer.

  The anterior eye portion of the eye 300 is irradiated with near infrared light (for example, wavelength 950 nm) from a light source (not shown), and the reflected light from the eye 300 is observed through the dichroic mirrors 130 and 129. An image is formed on the image sensor 133 of the system. Imaging by the near-infrared light of the anterior eye part (pupil) of the eye to be examined is performed by the imaging element 133. The imaging element 133 is configured by a CCD or a CMOS image sensor.

(basic action)
First, the basic operation will be described. The SLO measurement light from the light source 101 passes through the half mirror 110, the first scanner 114, the deformable mirror 117, the second scanner 120, the third scanner 123, the diopter correction system 125, the objective lens 131, and the fundus of the eye 300 to be examined. Irradiated to 301 in a condensed state. The SLO measurement light applied to the fundus 301 is reflected at the condensing point of the fundus 301. This reflected light follows the reverse path as described above as SLO detection light, passes through the half mirror 110, and is detected by the fundus reflection light detector 113.

  A part of the SLO detection light is reflected by the half mirror 110 toward the half mirror 104, further reflected by the half mirror 104, and detected by the wavefront detection unit 105. In the wavefront detection unit 105, wavefront disturbance in the SLO detection light is detected, and the detection signal is sent to the calculation unit 203. The calculation unit 203 controls the deformable mirror 117 so as to suppress the disturbance of the wavefront detected by the wavefront detection unit 105. Thereby, disturbance of the wavefront of the SLO detection light can be suppressed. In this way, the wavefront of the detection light is corrected while detecting the reflected light from the fundus.

  In the above process, the following scanning operation is performed. First, a two-dimensional area scan is performed by a combination of a vertical scan of the first scanner 114 performed at a relatively high speed and a horizontal scan of the second scanner 120 performed at a relatively low speed. This scan is a wide area scan performed in a wide area. FIG. 2A shows an example of a wide area scan.

  At this time, the scan center of the first scanner 114 (the center of the range in which scanning is performed) cannot be changed, but when the third scanner 123 is moved, the scan range of the first scanner 114 is translated in the vertical direction as a whole. That is, by moving the third scanner 123, the position of the scan center of the first scanner 114 moves in the vertical direction. An example of this is shown in FIG.

  On the other hand, the scan center of the second scanner 120 can be moved to a desired position. Therefore, by using the second scanner 120 and the third scanner 123, the center of the two-dimensional scan by the first scanner 114 and the second scanner 120 can be changed. Here, by narrowing the scan range, it is possible to perform a finer scan centering on a specific position in the wide-area scan region. Then, an enlarged image obtained by enlarging a part of the image obtained by the wide area scan can be obtained. An example of this is shown in FIGS. 2E and 2F.

  Hereinafter, the principle of obtaining the enlarged image will be described based on a specific example. First, FIG. 2A conceptually shows that a wide area is scanned by the operation of the first scanner 114 that performs high-speed scanning in the vertical direction and the second scanner 120 that performs low-speed scanning in the horizontal direction. Has been.

  FIG. 2B shows a state in which the scanning range of the first scanner 114 is narrowed in the scanning state shown in FIG. In this case, since the first scanner 114 cannot change the position of the scan center, the upper and lower scan ranges are narrowed. Here, when the reflecting surface of the third scanner 123 that can arbitrarily set the position of the scan center is moved, the state shown in FIG. 2B can be changed to the state shown in FIG. 2C, for example. That is, in the state of FIG. 2B in which the scan range is narrowed in the vertical direction, the scan range is moved upward by shaking the reflecting surface of the third scanner 123, and the state of FIG. it can.

  In the state of FIG. 2C, when the scan range of the second scanner 120 is narrowed, the horizontal scan width is narrowed, and the state of FIG. 2D is obtained. Further, when the scanning range of the second scanner 120 is moved to the left and right, the states of FIG. 2D to FIG. 2E or the states of FIG. 2D to FIG. 2F are obtained. Here, if the scan range of the first scanner 114 and the scan range of the second scanner 120 are further narrowed, the narrow area scan range shown in FIGS. 2D to 2F can be further narrowed vertically and horizontally.

  FIG. 2C shows a case where the scan range by the third scanner 123 is moved upward. FIG. 2C shows that the scan range by the third scanner 123 is moved downward. The scan range of the narrow region in (D) to (F) can be set below the scan range in the region shown in FIG. Further, since the scan range of the first scanner 114 and the second scanner 120 can be narrowed to a desired range, as a result, a narrow area scan of the desired range is performed at a desired position in the scan range shown in FIG. It can be carried out.

  Based on the above principle, the first scanner 114, the second scanner 120, and the third scanner 123 are used in cooperation with each other at a desired position in a wide scanning range in the first stage of FIG. Narrow region scan, that is, a scan to enlarge a part of the scan.

  In this narrow area scan, the scan range of the first scanner 114 and the second scanner 120 is narrowed. When the scan range is narrowed, detection reflected light is sampled from a narrower range, so that the information density is increased and more precise pixel information with improved resolution can be obtained. That is, a fundus image obtained by enlarging a part of the fundus image obtained in the case of FIG. Note that since the scan density is limited by the collection range of the measurement light (for example, about several μm in diameter), there is a general limit in enlarging the fundus image.

  On the other hand, by changing the scan center position of the third scanner 123 without changing the respective scan ranges at the time of wide-area scanning by the first scanner 114 and the second scanner 120, the light projecting system corresponds to a wide angle. In some cases, the image range can be made wider than that shown in FIG.

(Control system)
Hereinafter, an example of the control system of the ophthalmologic apparatus shown in FIG. 1 will be described. FIG. 3A shows a block diagram of a control system of the ophthalmologic apparatus of FIG. In FIG. 3A, input operation information from an input device (not shown) is input to the input unit 220. As the input device, a keyboard device, a device using a GUI (graphical user interface), a device using a touch panel display, or the like can be used. In recent years, various portable information processing terminals that can use a GUI have been used, but it is also possible to perform various operations using these portable information processing terminals and receive the contents of operations by the input unit 220. It is. For example, the input unit 220 receives a designation from a user (an operator of the ophthalmologic apparatus) who enlarges a part of the fundus image.

  The arithmetic unit 203 includes a CPU and other hardware, and is configured by a microcomputer having various arithmetic functions and interface functions. FIG. 3B shows a configuration when the calculation unit 203 is grasped as a functional block. Each functional unit illustrated in FIG. 3B may be configured as software so that a predetermined function is exhibited by the calculation of the CPU, or at least a part thereof may be configured with dedicated hardware. .

  In FIG. 3B, the scanner control unit 311 performs processing for scanning irradiation light (measurement light) to the fundus 201. The scanner control unit 311 performs processing for determining the operation timing of each scanner, depending on how the first scanner 114, the second scanner 120, and the third scanner 123 are operated in cooperation. For example, processing for performing the scan shown in FIG. The output of the scanner control unit 311 is sent to the first scanner driving unit 207, the second scanner driving unit 208, and the third scanner driving unit 209. The first scanner 114, the second scanner 120, and the third scanner 123 are driven by these driving units and the operations determined by the scanner control unit 311 are performed.

  The relationship between the variable angle range of the reflector of the first scanner 114 and the scan range in the fundus image, the relationship between the scanner center of the second scanner 120 and the coordinates of the fundus image, the variable angle range of the second scanner 120 and the fundus image The relationship between the scan range in the first scanner 123, the relationship between the scanner center of the third scanner 123 and the coordinates of the fundus image, and the relationship between the variable angle range of the third scanner 123 and the scan range in the fundus image have been examined in advance. Is stored in the memory 205.

  For example, it is assumed that a wide-range fundus image shown in FIG. 2A is obtained and displayed on the display unit 204 described later. In this state, it is assumed that the user of the ophthalmologic apparatus observes the above wide-range fundus image, and performs an operation for enlarging and displaying the scan portion shown in FIG. In this case, setting the scan width of the first scanner 114, setting the scan center and scan width of the second scanner 120, and the position of the variable mirror of the third scanner 123 so that the scan range shown in FIG. Setting is performed in the scanner control unit 311.

  For example, when obtaining the state of FIG. 2E from the state of FIG. 2A, the process of setting the scan width of the first scanner 114 to half that of FIG. 2A, the scan center of the second scanner 120 2A to the left from the state of FIG. 2A, and the process of making the scan width half that of FIG. 2A, the angle of the variable mirror of the third scanner 123 The scanner control unit 311 performs a process for causing the scan center of the first scanner to deviate from the state of FIG.

  The image processing unit 315 performs processing related to the fundus image. The image processing unit 315 includes a fundus image creation unit 316. The fundus image creation unit 316 creates a retina image based on the scan data of the reflected light detected by the fundus reflection light detector 113. The retina image is sent to a display (not shown) and displayed there. That is, the output of the fundus reflection light detector 113 is converted into a digital signal by an ADC (A / D converter) 202 and sent to the arithmetic unit 203. The fundus 201 (see FIG. 1) is irradiated with light from the light source 101 while being scanned. The irradiation point at this time is determined by the scanner control unit 311. The position of the irradiation point at a certain moment is This is known on the calculation unit 203 side. Therefore, the fundus image can be obtained by converting the output of the ADC 202 to the shade of the assigned image corresponding to the scan position. This process is performed in the fundus image creation unit 316. In addition, the image processing unit 315 performs processing related to the enlarged display of the fundus image.

  The wavefront aberration detection unit 317 performs analysis (Zernike analysis) of the image captured by the Hartmann imaging device 107 and detects the state of aberration of the wavefront. The adaptive optics control unit 318 performs control to deform the deformable mirror 111 so as to suppress the aberration of the wavefront detected by the wavefront correction processing unit 317. In addition, the calculation unit 203 performs processing for ON / OFF control of the light source 101, processing for diopter correction, and the like.

  The display unit 204 displays various displays necessary for operating the ophthalmologic apparatus of FIG. 1 and the fundus image obtained by the calculation unit 203. Note that a display function of an external device may be used as the display unit 204. In this case, a process related to image data desired to be displayed by a display control unit (not shown) is performed and transmitted to the external device. The memory 205 stores various information necessary for the calculation performed by the calculation unit 203 and a program for determining the procedure of the calculation performed by the calculation unit 203. The memory 205 stores various calculation results and image data of the obtained fundus image.

  The control unit 206 generates a control signal for performing scanning operation control, light source 101 control, deformable mirror 111 control, diopter correction mirror 126 position control, and the like based on the processing result in the calculation unit 203. .

  The first scanner drive unit 207 includes a motor for moving the first scanner 114 and its drive circuit. The second scanner drive unit 208 includes a motor for moving the second scanner 120 and its drive circuit. The third scanner driving unit 209 includes a motor for moving the third scanner 123 and its driving circuit. The diopter correction mirror drive unit 210 includes a motor that determines the position of the diopter correction mirror 126 on the optical axis and a drive circuit therefor.

(Operation example)
FIG. 4 is a flowchart showing an example of operations performed in the control system of FIG. When the operation is started, first, eye alignment is performed (step S101). In this process, the eye to be examined 300 (see FIG. 1) and the optical axis of the apparatus are aligned. Next, the line of sight of the eye 300 is fixed using the fixation target 132 (step S102), and then the fundus 301 is photographed (step S103).

  In step S103, the fundus is imaged in the wide angle mode. In this processing, laser light irradiation from the light source 101 is performed while scanning the fundus, and the reflected light is detected by the fundus reflection light detector 113. At this time, as shown in FIG. 2A, the laser beam is irradiated while scanning the wide area of the fundus. Then, based on the reflected light from the fundus of the scan light, the fundus is imaged to obtain a wide-angle image of the fundus. This wide-angle image of the fundus is an image of a region as large as possible of the fundus to be imaged. The above-described processing for obtaining the fundus image is performed in the fundus image creation unit 316.

  Further, the wavefront correction of the detection light is performed simultaneously with the above scan. In this process, the state of the wavefront of the detection light is detected by the wavefront detection system, and the surface shape of the deformable mirror 117 is deformed so as to suppress the aberration of the wavefront.

  After step S103, the wide-angle fundus image obtained in step S103 is displayed on the display unit 204 of FIG. 1 (step S204). FIG. 5A shows an example of a state in which a wide-angle fundus image is displayed on the screen. Here, using a GUI (Graphical User Interface), whether to enlarge the image simultaneously with the fundus image, or how to change the visual field size (that is, the enlarged size) when further enlarging the image is selected. Is displayed.

  In the state shown in FIG. 5A, when an image enlargement and a visual field size are selected by a GUI operation by the user, the apparatus recognizes that an instruction to shift to the enlargement shooting mode is given, and the determination in step S105 is made. Yes. If “NO” is clicked in the state of FIG. 5A or 5B, it is determined that an instruction to shift to the enlarged shooting mode has not been issued, and the process proceeds from step S105 to step S106.

  When the process proceeds to step S106, enlarged photographing of a plurality of predetermined parts is performed. FIG. 6B shows an example in which four predetermined portions in the wide-angle image shown in FIG. 6A are magnified. In this process, the principle shown in FIG. 2 is used to perform an enlarged scan (see FIG. 2E or FIG. 2F) with the determined portion as the scan center. For example, the specific portion in FIG. A rescan of a narrow area is performed. Then, an enlarged image is created based on the rescan. Here, the scan control is performed by the scanner control unit 311 in FIG. 3B, and the fundus image is imaged by the fundus image creation unit 316. While step S106 is being performed, the subject's line of sight remains fixed at the position specified in step S102 and does not need to move.

  After step S106, the enlarged fundus image is displayed simultaneously with the wide-angle fundus image (step S111). An example of the display in this case is shown in FIG.

  If the determination in step S105 is YES, that is, if the user instructs the shift to the enlarged image shooting mode, the visual field size designated by the user in FIG. 5B is acquired (step S107). Then, a cursor indicating the size of the visual field is displayed on the fundus wide-angle image (step S108). This state is shown in FIG. FIG. 6C shows an example in which a cursor indicating the range of the field of view of the enlargement portion selected by the user is displayed in the fundus image in addition to the predetermined four enlargement portions. .

  The cursor indicating the range of the visual field can be moved on the screen by a known GUI operation such as a mouse operation or a touch panel operation. By moving the cursor, the position in the wide-angle fundus image that the user wants to enlarge is specified.

  When “OK” in FIG. 5B is clicked with the enlargement position specified by the cursor, the apparatus side (calculation unit 203) recognizes that enlargement photography has been instructed, and the determination in step S109 is YES. Thus, enlarged photographing at the designated position is performed (step S110). In this process, an enlarged scan (see FIG. 2E or FIG. 2F) with the portion specified by the user as the scan center is performed using the principle shown in FIG. Then, an enlarged image is created based on the rescan. Here, the scan control is performed by the scanner control unit 311 in FIG. 3B, and the fundus image is imaged by the fundus image creation unit 316. At this time, in addition to the portion designated by the user, enlargement photographing of a predetermined portion is performed. It should be noted that the line of sight of the subject remains fixed at the position specified in step S102 and does not need to be moved even during the execution of steps S107 to S110.

  After step S110, the process proceeds to step S111, where an enlarged fundus image of a predetermined part and an enlarged fundus image of a part specified by the user are displayed on the screen of the display unit 204 (step S111). An example of the screen display in this case is shown in FIG.

(Example 1)
FIG. 7 shows an example in which a grid is set on the wide-angle fundus image, and this grid corresponds to the horizontal scan angle by the second scanner 120 and the vertical scan angle by the third scanner 123. . In this case, when an arbitrary location in the wide-angle image is designated by the user, the scan center and the scan range are set so that the intersection of the grid closest to the designated location is the scan center, and a predetermined viewing angle is set. An enlarged image can be obtained.

(Example 2)
FIG. 8 shows a configuration in which a grid is set on the wide-angle fundus image in the same manner as in FIG. 7. When the user selects a visual field size, a cursor corresponding to the visual field size appears in the wide-angle image. An example is shown in which an enlarged portion is determined by dragging in a wide-angle image. In this example, an enlarged image is obtained around the intersection of the grids closest to the designated part.

(Other)
The relationship between the scanning directions of the first scanner and the second scanner may not be orthogonal. In this case, the scan range is a parallelogram. Further, as long as the scanning range of the first scanner can be moved in the scanning direction of the first scanner, the variable directions of the first scanner and the third scanner may not be the same.

(Superiority)
According to the ophthalmologic apparatus described above, a wide-angle fundus image can be obtained first, and an enlarged image at a position designated by the user can be obtained while fixing the line of sight of the subject.

  The present invention can be used for an ophthalmologic apparatus.

  DESCRIPTION OF SYMBOLS 100 ... Ophthalmological apparatus 101 ... Light source 102 ... Optical fiber 103 ... Lens (collimator lens) 104 ... Half mirror 105 ... Wavefront detection part 106 ... Lens array 107 ... CCD 109 ... Optical system 110 ... Half Mirror, 111 ... lens, 112 ... pinhole, 113 ... fundus reflection light detector, 114 ... first scanner, 115 ... relay lens, 116 ... relay lens, 117 ... deformable mirror, 118 ... relay lens, 119 ... relay lens 120 ... second scanner, 121 ... relay lens, 122 ... relay lens, 123 ... third scanner, 124 ... relay lens, 125 ... diopter correction system, 126 ... diopter correction mirror, 127 ... diopter correction mirror, 128 ... Lens system, 129 ... Dichroic mirror, 130 ... Dichroic mirror, 1 1 ... objective lens, 132 ... fixation target 133 ... imaging element, 300 ... subject's eye, 301 ... fundus.

Claims (4)

A measurement light irradiator that irradiates the fundus with measurement light;
A first scanner that performs a relatively high-speed scan of the measurement light in a first direction;
It is possible to scan the measurement light in a direction perpendicular to the first direction at a relatively low speed, and to move a scanning range by the first scanner in a direction perpendicular to the first direction. A second scanner that can be modified;
A third scanner capable of moving a scanning range of the first scanner in the first direction and changing a scanning center;
A scanner control unit for controlling the first scanner, the second scanner, and the third scanner;
A reflected light detector that detects reflected light from the fundus of the measurement light;
A fundus image creating unit that creates a fundus image of the fundus based on the reflected light;
A designation receiving unit that receives designation of a specific part in the fundus image ;
A fixed index that is a visual target for fixing the orientation or line of sight of the eye to be examined ,
The scanner control unit
Control for controlling the second and third scanners so that the scanning center of the first scanner is positioned at the specific portion, and changing the position of the scanning center of the first scanner;
There line and a scan control of the first scanner and the second scanner by narrowing the scanning range after a change of the position of the scanning center of the first scanner by the second and third scanner is performed,
The ophthalmic apparatus characterized in that the fixed index moves to guide the direction or line of sight of the eye to be examined in a direction intended by a user . The ophthalmologic apparatus according to claim 1, wherein the fixed index is movable in a direction perpendicular to the optical axis of the measurement light . The ophthalmologic apparatus according to claim 1, wherein the solid index is composed of a film that emits visible light or an organic EL element . The scanner control unit
The relationship between the variable angle range of the reflector of the first scanner and the scan range in the fundus image;
A relationship between the scanner center of the second scanner and the coordinates of the fundus image;
A relationship between a variable angle range of the second scanner and a scan range in the fundus image;
A relationship between the scanner center of the third scanner and the coordinates of the fundus image;
The first scanner, the second scanner, and the third scanner are controlled based on a relationship between a variable angle range of the third scanner and a scan range in the fundus image. The ophthalmologic apparatus as described in any one of 1-3.

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