JP2005160549A - Fundus camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fundus camera easily photographing a favorable fundus image without requiring a skill by automating the photographing. <P>SOLUTION: This fundus camera is provided with a photographing optical system having a focusing lens movable in the optical axis direction for photographing a fundus oculi of the eye to be examined, which is illuminated by a photographing illumination light, an alignment detecting means detecting the alignment state of the photographing optical system relative to the eye to be examined, a focus detecting means detecting the focus state of the fundus oculi adjusted by the movement of the focusing leans, a pupil and visual line detecting means detecting at least one of the pupil state and the visual line direction of the eye to be examined, and an automatic photographing means automatically executing the photographing by the photographing optical system based on the detection result of the detecting means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fundus camera that photographs the fundus of a subject's eye.

In the fundus camera, the fundus is imaged after performing alignment adjustments in the vertical, horizontal, and longitudinal (working distance) direction of the fundus imaging optical system with respect to the eye to be examined, and focus adjustment that focuses on the fundus according to the diopter of the eye to be examined. doing. Conventionally, alignment adjustment and focus adjustment have been manual adjustment by an examiner's operation, but recently, a fundus camera having functions of automatic alignment and automatic focus has also been proposed (see, for example, Patent Document 1).
JP-A-8-275922

  However, in fundus photography, even if automatic alignment and automatic focus functions are provided, there are still difficulties in obtaining a good fundus image by an unskilled examiner. That is, in order to obtain a good fundus image, it is important that the illumination light for photographing is appropriately incident on the fundus during photographing. If the pupil diameter is small and the photographic illumination light is shielded by the iris and does not enter the fundus appropriately, the amount of illumination will be insufficient. In addition, if the line of sight of the eye to be examined is not guided in the direction of the fixation target as planned, the fundus may not be scheduled and focus adjustment cannot be performed smoothly, and the captured image will be in focus. Is likely to shift. If a fundus image of a planned site and a clear fundus image are not obtained, re-imaging increases. For this reason, a fundus camera that automatically performs photographing has not been put into practical use.

  In view of the problems of the conventional apparatus, it is an object of the present invention to provide a fundus camera that automates photographing so that good fundus photographing can be easily performed without requiring skill.

(1) An imaging optical system having a focusing lens movable in the optical axis direction for imaging the fundus of the eye illuminated by the imaging illumination light, and an alignment detection means for detecting the alignment state of the imaging optical system with respect to the eye to be examined A focus detection unit that detects a focus state of the fundus adjusted by the movement of the focusing lens, a pupil / gaze detection unit that detects at least one of a pupil state and a gaze direction of the eye to be examined, and detection of these detection units Automatic photographing means for automatically performing photographing by the photographing optical system based on the result.
(2) In the fundus camera of (1), an automatic alignment unit that moves the photographing optical system with respect to the eye to be examined based on a detection result of the alignment detection unit, and a detection result of the focus detection unit And an automatic focusing means for moving the focusing lens.
(3) In the fundus camera of (1), the fundus observation optical system having a first image pickup unit that images the fundus oculi to be examined, and the optical path branching member disposed in the optical path of the fundus oculi observation optical system in front of the eye to be examined An anterior ocular segment observation optical system having a second imaging unit for imaging the eye, and the pupil / gaze detection unit detects a pupil state and a gaze direction based on the anterior segment image captured by the second imaging unit. At least one of them is detected.
(4) In the fundus camera of (1), the detection of the pupil state by the pupil / line-of-sight detection means is based on whether or not the pupil edge is located outside a predetermined area centered on the imaging optical axis of the imaging optical system. It is characterized by detecting the suitability of the state.
(5) The fundus camera of (1) is provided with a fixation target optical system that presents a fixation target to the eye to be examined, and the detection of the gaze direction by the pupil / gaze detection unit is performed by the fixation target optical system. Whether or not the eye gaze direction is appropriate is detected based on whether or not the center of the pupil is located within a predetermined area defined by the relationship with the target presentation position.
(6) In the fundus camera of (1), the detection optical system for observing the fundus of the eye illuminated by the observation illumination light source and the detection results of the alignment detection means, focus detection means, and pupil / gaze detection means are both appropriate An informing means for informing the examiner of the fact and an input means for the examiner to input a photographing permission signal, and the automatic photographing means has the alignment after the photographing permission signal is inputted. The imaging is automatically executed based on the detection results of the detection means, the focus detection means, and the pupil / gaze detection means.

  According to the present invention, it is possible to easily perform good fundus imaging with less imaging failure without requiring skill.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of a non-mydriatic retinal camera according to the present invention.

  The fundus camera includes a base 1, a movable base 2 that can be moved in the left-right direction (X direction) and the front-back direction (Z direction) by moving the joystick 4 with respect to the base 1, and the left and right relative to the movable base 2. An imaging unit 3 provided so as to be able to move three-dimensionally in the up and down and front and rear directions (Z direction) and a face support unit 5 fixed to the base 1 for supporting the face of the subject. Reference numeral 6 denotes a Y drive unit that moves the photographing unit 3 in the vertical direction, and reference numeral 7 denotes an XZ drive unit that moves the photographing unit 3 back and forth. The XZ drive unit 7 arranges a Z table movable in the Z direction on the Y table, arranges an X table movable in the X direction on the Z table, and arranges the photographing unit 3 on the X table. Then, the photographing unit 3 is moved in the XY directions by driving the Z table and the X table by motors. The Y drive unit 6 moves the photographing unit 3 in the Y direction by driving the Y table up and down by a motor. This type of three-dimensional drive mechanism can be a known mechanism. The photographing unit 3 is moved up and down by the Y drive unit 6 being operated by rotating the joystick 4. A monitor 8 for displaying an observation image or a photographed image is provided on the examiner side of the photographing unit 3.

  FIG. 2 is a schematic configuration diagram of an optical system and a control system housed in the photographing unit 3. The optical system is roughly divided into an illumination optical system 10, a fundus observation / photographing optical system 30, a focus index projection optical system 40, an alignment index projection optical system 50, an anterior ocular segment observation optical system 60, and a fixation target optical system 70. ing.

  The illumination optical system 10 includes an observation illumination optical system and a photographing illumination optical system. The photographing illumination optical system includes a photographing light source 14 such as a flash lamp, a condenser lens 15, a ring slit 17 having a ring-shaped opening, a relay lens 18, a mirror 19, a black spot plate 20 having a black spot at the center, a relay lens 21, and a hole. A perforated mirror 22 and an objective lens 25 are provided. The observation illumination optical system includes a light source 11 such as a halogen lamp, an infrared filter 12 that transmits near-infrared light having a wavelength of 750 nm or more, a condenser lens 13, and a dichroic disposed between the condenser lens 13 and the ring slit 17. An optical system from the mirror 16 and the ring slit 17 to the objective lens 25 is provided. The dichroic mirror 16 has a characteristic of reflecting infrared light and transmitting visible light.

  The fundus oculi observation / imaging optical system 30 includes an objective lens 25, a photographing aperture 31 located near the aperture of the perforated mirror 22, a focusing lens 32 movable in the optical axis direction, an imaging lens 33, infrared light reflection, and visible light. A dichroic mirror 34 having transmission characteristics is provided, and the photographing optical system and the fundus observation optical system share the objective lens 25 and the optical system from the photographing aperture 31 to the imaging lens 33. The photographing aperture 31 is disposed at a position substantially conjugate with the pupil of the eye E with respect to the objective lens 25. The focusing lens 32 is moved in the optical axis direction by a moving mechanism 39 including a motor. In the transmission direction of the dichroic mirror 34, a color CCD camera 35 for photographing having sensitivity in the visible range is arranged. In the optical path in the reflection direction of the dichroic mirror 34, an infrared reflection and visible light transmission dichroic mirror 37, a relay lens 36, and an observation CCD camera 38 having sensitivity in the infrared region are arranged.

  A dichroic mirror (wavelength selective mirror) 24 that can be inserted and removed as an optical path branching member is obliquely disposed between the objective lens 25 and the perforated mirror 22, and further, the dichroic mirror 24 and the perforated mirror 22 are provided. Between them, a parallel plate glass 23 for correcting an optical axis shift by the dichroic mirror 24 is obliquely installed so as to be detachable. The dichroic mirror 24 reflects the wavelength light (center wavelength 940 nm) of the alignment index projection optical system 50 and the anterior segment illumination light source 58, and the wavelength light of observation illumination and the light source wavelength (center wavelength of the focus index projection optical system 40). 880 nm) and a wavelength of 900 nm or less. The parallel plate glass 23 has substantially the same thickness as the dichroic mirror 24 and almost the same refractive index. As shown in FIG. 4, the dichroic mirror 24 and the parallel plate glass 23 are disposed so as to have the same inclination angle θ as a contrast with respect to the optical axis L1 of the fundus oculi observation / photographing optical system. At the time of photographing, the dichroic mirror 24 and the parallel plate glass 23 are flipped up by the insertion / removal mechanism 66 and retracted out of the optical path. The insertion / removal mechanism 66 can be composed of a solenoid and a cam.

  The focus index projection optical system 40 includes an infrared light source 41, a slit index plate 42, two declination prisms 43 attached to the slit index plate 42, and a half mirror 44 obliquely provided in the optical path of the illumination optical system 10. . The light source 41 and the slit index plate 42 are moved in the optical axis direction by the moving mechanism 39 in conjunction with the focusing lens 32.

  The light flux of the slit index plate 42 of the focus index projection optical system 40 is reflected by the half mirror 44 via the deflection prism 43, and then the relay lens 21, the perforated mirror 22, the parallel plate glass 23, the dichroic mirror 24, the objective lens. 25 and projected onto the fundus of the eye E to be examined. When the fundus is out of focus, the index image of the slit index plate 42 is separated and projected in agreement when in focus.

  The alignment index projection optical system 50 includes two sets of first index projection optical systems disposed symmetrically about the optical axis of the objective lens 25, and an optical axis disposed at a narrower angle than the first index projection optical system. And two sets of second index projection optical systems arranged symmetrically with respect to a vertical plane through which the optical axis L1 passes. The two sets of first index projection optical systems each have a light source 51 and a collimating lens 52 that emit infrared light having a center wavelength of 940 nm, and project an infinite target on the eye to be examined by light of a substantially parallel light beam. On the other hand, the two sets of second index projection optical systems have a light source 52 that emits infrared light having a center wavelength of 940 nm, and project a target at a finite distance onto the eye to be examined by a divergent light beam. 2 shows the optical system as viewed from the side, but the alignment index projection optical system 50 is actually arranged in the left-right direction. FIGS. 5A and 5B show the state of the index image formed on the anterior segment image F by the alignment index projection optical system 50. The index images Ma and Mb are the first index projection optical system ( An index image at infinity by the light source 51 and the collimating lens 52), and the index images Mc and Md are index images at a finite distance by the second index projection optical system (light source 53). The second index projection optical system is configured so that the index images Mc and Md are formed below the index images Ma and Mb.

  In addition, as shown in FIG. 3, two infrared light sources 55 (center wavelength 880 nm) for forming working dots are arranged symmetrically around the optical axis L1 around the hole of the perforated mirror 22. Yes. The light source 55 may be configured such that the end face of the optical fiber is disposed in the vicinity of the perforated mirror 22 and the infrared light is guided to the optical fiber. The light source 55 is disposed such that when the working distance between the eye E and the objective lens 25 is appropriate, a distance that is ½ of the radius of curvature of the cornea is a conjugate position.

  The anterior ocular segment observation optical system 60 includes a field lens 61, a mirror 62, a diaphragm 63, a relay lens 64, and a CCD camera 65 having sensitivity in the infrared region on the reflection side of the dichroic mirror 24. The CCD camera 65 also serves as an alignment index detection unit, and the anterior segment illuminated by the anterior segment illumination light source 58 that emits infrared light having a center wavelength of 940 nm is imaged. The alignment index detection means is advantageously used also for anterior segment imaging, but a dedicated one may be provided.

  The fixation target presenting optical system 70 includes a red light source 74, a target plate 72 having eight fixation targets 71 formed with opening holes, and a relay lens 75. From the dichroic mirror 34 via the dichroic mirror 34. The optical path of the observation optical system 30 up to the objective lens 25 is shared. The fixation target 71 has an aperture that leads the vicinity of the posterior pole of the right eye to the imaging center, an aperture that guides the vicinity of the posterior pole of the left eye to the imaging center, and a line of sight so as to photograph the peripheral portion. The fixation target 71 is selectively arranged in front of the light source 74 by the motor 73.

  In the above optical system, the anterior segment illuminated by the anterior segment illumination light source 58 is received by the CCD camera 65 from the objective lens 25, the dichroic mirror 24, and the field lens 61 via the relay lens 64 optical system. The light beam emitted from the observation light source 11 is converted into an infrared light beam by the infrared filter 12 and reflected by the condenser lens 13 and the dichroic mirror 16 to illuminate the ring slit 17. The light transmitted through the ring slit 17 reaches the perforated mirror 22 through the relay lens 18, the mirror 19, the black spot plate 20, and the relay lens 21. The light reflected by the perforated mirror 22 passes through the parallel plate glass 23 and the dichroic mirror 24, and once converges near the pupil of the eye E by the objective lens 25, and then diffuses to illuminate the fundus of the eye to be examined. The luminous flux emitted from the imaging illumination light source 14 passes through the condenser lens 15 and then illuminates the fundus of the eye to be examined through the same optical path as the observation illumination luminous flux.

  Reflected light from the fundus illuminated by the observation illumination light is the objective lens 25, the dichroic mirror 24, the parallel plate glass 23, the aperture of the perforated mirror 22, the photographing aperture 31, the focusing lens 32, the imaging lens 33, and the dichroic mirror 34. The image is formed on the CCD camera 38 via the dichroic mirror 37 and the relay lens 36. At this time, as shown in FIG. 4, the optical axis L1 of the fundus oculi observation / imaging optical system becomes an optical axis L1a that is deviated by the insertion of the dichroic mirror 24. The excursion is returned. For this reason, the imaging of the anterior segment by the CCD camera 65 and the imaging of the fundus by the CCD camera 38 can be performed satisfactorily at the same time.

  Here, when there is no parallel plate glass 23, the displaced optical axis L1a does not pass through the center of the photographing aperture 31. In this case, the center of the ring illumination light reflected by the anterior segment and the center of the photographing aperture 31 are shifted, and even when alignment is completed, the CCD camera 38 for fundus observation reflects from the anterior segment. Light enters. For this reason, flare light tends to occur in the observation elephant, a good fundus observation image cannot be obtained, and the focus index cannot be detected accurately.

  At the time of photographing, the dichroic mirror 24 and the parallel plate glass 23 are retracted out of the optical path by the insertion / removal mechanism 66, and the reflected light from the fundus illuminated by the photographing illumination light includes the objective lens 25, the perforated mirror 22, the photographing aperture 31, An image is formed on a CCD camera 35 for photographing through a focusing lens 32 and a dichroic mirror 34. The CCD camera 35 can also be used as an observation camera.

  The outputs of the CCD cameras 65, 38, and 35 are connected to the image processing unit 80. The image processing unit 80 detects the alignment index from the anterior eye image captured by the CCD camera 65 and detects the focus index from the fundus image captured by the CCD camera 38. The image processing unit 80 is connected to the monitor 8 and controls the display image. The control unit 81 includes an image processing unit 80, a Y drive unit 6, an XZ drive unit 7, a joystick 4, a moving mechanism 39, an insertion / removal mechanism 66, a photographing switch 83, a switch unit 84 having various operation switches, and light sources. It is connected.

  The operation of the apparatus having the above configuration will be described. In this apparatus, the manual alignment mode and the automatic alignment mode can be selected by the switch 84a of the switch unit 84, and the automatic shooting mode in which the photographing is automatically executed when the photographing possible condition is satisfied by the switch 84d, and the examiner switches the photographing switch. A manual shooting mode in which shooting is performed by pressing 83 can be selected. Here, the case where the automatic alignment mode and the automatic photographing mode are selected will be described using the flowchart of FIG.

  At the time of photographing, the face of the examiner is supported by the face support unit 5. At the initial stage, the dichroic mirror 24 and the parallel plate glass 23 are inserted in the optical path of the fundus oculi observation / imaging optical system 30. The anterior segment illuminated by the anterior segment illumination light source 58 is received by the CCD camera 65 from the objective lens 25, the dichroic mirror 24 and the field lens 61 via the optical system of the relay lens 64. An anterior segment image captured on the screen is displayed. The examiner observes the anterior segment image displayed on the monitor 8, and adjusts the imaging unit 3 roughly with respect to the subject's eye by operating the joystick 4. When the anterior segment image appears on the monitor 8, as shown in FIG. 5A, four index images Ma, Mb, Mc, and Md also appear. In FIG. 5, Na, Nb, Nc, and Nd are line-shaped reticle marks, and Ne is a ring mark that indicates a pupil diameter necessary for imaging. These are electrically formed by the image processing unit 80. It is a thing. As shown in FIG. 5B, the alignment in the manual mode is performed by moving the imaging unit 3 left and right so that the index images Ma, Mb, Mc, and Md are positioned on the reticle marks Na, Nb, Nc, and Nd. Move up and down. In the front-rear direction (working distance direction), the combined photographing unit 3 is moved so that the index image is focused.

  When the four index images Ma to Md picked up by the CCD camera 65 are detected by the image processing unit 80, the control unit 81 obtains a deviation amount (positional deviation) with respect to the alignment reference based on these index images. . As shown in FIG. 6, the control unit 81 obtains a deviation amount Δd with respect to the alignment reference position O in the XY directions with the intermediate position between the index images Ma and Mb as the corneal apex position Mo. Then, the automatic alignment by the drive control of the XZ drive unit 7 and the Y drive unit 6 is operated so that the deviation amount Δd falls within the allowable range A for completion of alignment. Depending on whether the deviation amount Δd is within the allowable range A for completion of alignment and the time continues for a certain time (for example, 10 frames for image processing or 0.3 seconds) (whether the alignment condition A is satisfied). , Whether the alignment in the XY directions is appropriate or not is determined.

  Further, the alignment state in the Z direction is detected by comparing the interval between the index images Ma and Mb and the interval between the index images Mc and Md. This is because when the corneal reflection image is formed by an infinite light source and a finite light source, the image height of the corneal reflection image by the infinite light source does not change even if the working distance changes, but the image height by the finite light source does not change. This utilizes the characteristic that it changes as the working distance changes (refer to Japanese Patent Laid-Open No. 6-46999 for details). For the Z direction, based on the same idea as in FIG. 6, the amount of deviation with respect to the alignment reference position in the Z direction is obtained, and automatic alignment by drive control of the XZ drive unit 7 is performed so that the amount of deviation falls within the allowable range A for completion of alignment. Actuate. Whether or not the alignment in the Z direction is appropriate is determined based on whether or not the deviation amount in the Z direction is within the allowable range A for completion of alignment for a certain period of time (whether the alignment condition A is satisfied).

  When the alignment state in the XYZ directions satisfies the alignment completion condition A, the control unit 81 further determines whether the line-of-sight direction and the pupil diameter (pupil state) are appropriate after stopping the automatic alignment operation. An example of appropriateness determination of the line-of-sight direction and the pupil diameter will be described. FIG. 7 is a diagram when the alignment of the right eye is completed. First, the suitability of the line-of-sight direction is determined by whether or not the pupil center P1 detected from the anterior segment image F shown in FIG. 7 is in the line-of-sight determination area T1. The pupil center P1 is obtained, for example, as the barycentric position of the pupil edge. In a simple manner, the pupil edge can be detected in the horizontal direction and the vertical direction with reference to the center of the image, and can be obtained as the detected barycentric positions. At the time of alignment of the right eye, a fixation target 71 having an opening hole that guides the vicinity of the rear pole of the right eye to the imaging center is presented. When the right eye of the eye to be examined is gazing at the fixation target 71, if the pupil center P1 is in the line-of-sight determination area T1 having the center slightly on the right side of the alignment reference position Mo, the line-of-sight direction is determined to be appropriate. Is done. When the eye to be examined is not gazing at the fixation target 71, the line of sight flutters and deviates from the line-of-sight determination area T1.

  The suitability of the pupil diameter is determined by whether or not the pupil edge detected from the anterior segment image by the CCD camera 65 is out of the pupil determination area T2 shown in FIG. The size of the pupil determination area T2 is set as a diameter (for example, a diameter of 4 mm) through which the fundus illumination light beam can pass with the image center (imaging optical axis center) as a reference. For simplicity, four pupil edges detected in the horizontal direction and the vertical direction with respect to the center of the image are used. If the pupil edge point is outside the pupil determination area T2, the illumination light quantity at the time of photographing is sufficiently ensured, and the light flux of the focus index is projected onto the fundus, thereby improving the focusing reliability. .

  It should be noted that whether or not the line-of-sight direction and the pupil diameter are appropriate are also appropriate when appropriate conditions continue for a certain period of time, as in the determination of alignment completion.

  If the alignment completion condition A is satisfied, and both the line-of-sight direction and the pupil state are determined to be appropriate, the display image on the monitor 8 is automatically switched from the anterior ocular segment image to the fundus image. When at least one of the line-of-sight direction and the pupil state is not appropriate in the alignment completed state, information to that effect is displayed on the monitor 8 and notified to the examiner. By referring to the notification information, the examiner can take necessary measures before photographing, such as urging the subject to watch the fixation target or resting so that the pupil diameter is widened. Switching from the anterior ocular segment image to the fundus oculi image is performed automatically, but by displaying on the monitor 8 a mark 100 (see FIG. 5B) for informing the monitor 8 of the completion of alignment and the like. The person may switch the display by pressing the display switching button 84c of the switch unit 84.

  FIG. 8 is an example of a fundus image captured by the CCD camera 38, and focus index images S1 and S2 by the focus target projection optical system 40 are projected at the center of the fundus image. W is two working dots of corneal reflection formed by the light source 55. In the present apparatus, the optical system shown in FIG. 3 can simultaneously perform focus detection by the fundus oculi observation optical system in addition to alignment detection by the anterior ocular segment observation optical system, detection of the line-of-sight direction and pupil state. The focus index images S1 and S2 are separated when they are not in focus, and are projected in agreement when they are in focus. Although focusing can be performed manually by the examiner's operation, this apparatus has an autofocus mechanism. The focus index images S <b> 1 and S <b> 2 are detected and processed by the image processing unit 80, and the separation information is sent to the control unit 81. Based on the separation information of the focus index images S1 and S2, the control unit 81 controls the movement of the moving mechanism 39 so that the two coincide with each other, thereby focusing the fundus.

  When the focus is adjusted, the control unit 81 checks again whether the alignment state is appropriate and whether the line-of-sight direction and the pupil state are appropriate. In this device, the anterior segment observation optical system 60 can detect alignment and detect the line-of-sight direction and the pupil state even in the focus index detection stage. If the alignment state does not satisfy the alignment condition A, the automatic alignment is activated. The imaging unit 3 is made to track the movement of the eye to be inspected so as to complete the alignment. If the alignment state, the focus state, the line-of-sight direction, and the pupil state are appropriate (if the imaging conditions are satisfied), the control unit 81 automatically issues an imaging start signal and executes imaging. It should be noted that at the timing of performing imaging, confirmation is made including the presence or absence of blinking of the eye to be examined. The presence or absence of blinking can be detected not only from the anterior eye image captured by the CCD camera 65 of the anterior eye observation optical system 60 but also from the fundus image of the CCD camera 38 of the fundus observation optical system.

  The controller 81 drives the insertion / removal mechanism 66 to detach the dichroic mirror 24 and the parallel plate glass 23 from the optical path, and emits the photographing light source 14. The fundus is illuminated with visible light by the light emission of the imaging light source 14, and the reflected light from the fundus occupies the objective lens 25, the aperture of the perforated mirror 22, the imaging aperture 31, the focusing lens 32, the imaging lens 33, and the dichroic mirror 34. Then, an image is formed on the CCD camera 35. The display on the monitor 8 is switched to a color fundus image captured by the CCD camera 35 by the image processing unit 80. The fundus image captured by the CCD camera 35 is stored in an image memory included in the image processing unit 80.

  As described above, as conditions for automatic photographing, it is preferable to confirm both the suitability of the line-of-sight direction and the pupil state in addition to the suitability of alignment adjustment and focus adjustment. When the suitability of the line-of-sight direction is set as a condition for automatic imaging, it is possible to reduce failure to image an unplanned fundus region. When the suitability of the pupil state is set as a condition for automatic photographing, it is possible to reduce the failure of the photographed image to become dark and the failure of the flare to be placed because part or all of the photographing illumination light is shielded by the pupil.

  In the automatic photographing mode, the examiner can make a final confirmation before photographing. If the alignment adjustment, the focus adjustment, the line-of-sight direction, and the pupillary state are all appropriate, a mark for notifying that the photographing condition is satisfied is synthesized and displayed on the fundus observation image of FIG. 8, and automatic photographing is waited. When the examiner confirms that there is no flare in the fundus observation image and the examiner presses the photographing switch 83 to input the photographing permission signal, the control unit 81 receives the photographing permission signal and then performs alignment. Automatic shooting is executed at the timing when it is detected that the adjustment, the focus adjustment, the line-of-sight direction, and the pupil state are both appropriate. Thereby, even an examiner who takes time for photographing operation can easily photograph a good fundus image at an appropriate timing. When the fundus observation image has a flare or the like, it is possible to perform imaging based on the judgment of the examiner as in the conventional case by switching to the manual imaging mode and the manual alignment mode.

  In the above, the case of the automatic alignment mode has been described as an example. However, the automatic photographing mode can be applied even in the case of the manual alignment mode.

It is a block diagram of a non-mydriatic type fundus camera according to the present invention. It is a schematic block diagram of the optical system and control system accommodated in an imaging | photography part. It is a figure explaining arrangement | positioning of the light source for forming a working dot. It is a figure explaining the correction | amendment of the optical axis offset produced by an optical path branching member, and the optical axis offset by a parallel plate glass. It is a figure which shows the anterior ocular segment image imaged with the CCD camera for anterior ocular segment observation. It is a figure explaining the range of the position shift of alignment. It is a figure explaining the example of an appropriateness | judgment determination of a gaze direction and a pupil diameter. It is an example of a fundus image captured by a CCD camera for fundus observation. It is a flowchart explaining operation | movement of automatic imaging | photography mode.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Image pick-up part 4 Joystick 6 Y drive part 7 XZ drive part 8 Monitor 10 Illumination optical system 23 Parallel plate glass 24 Dichroic mirror 30 Fundus observation and imaging optical system 32 Focusing lens 35, 38, 65 CCD camera 40 Focus index projection optical system 50 Alignment Index projection optical system 60 Anterior ocular segment observation optical system 80 Image processing unit 81 Control unit

Claims (6)

An imaging optical system having a focusing lens movable in the optical axis direction for imaging the fundus of the eye illuminated by the imaging illumination light, an alignment detection means for detecting an alignment state of the imaging optical system with respect to the eye to be examined, and Based on the detection results of the focus detection means for detecting the focus state of the fundus adjusted by the movement of the focusing lens, the pupil / gaze detection means for detecting at least one of the pupil state and the line-of-sight direction of the eye to be examined, and these detection means And an automatic photographing means for automatically performing photographing by the photographing optical system. 2. The fundus camera according to claim 1, further comprising: an automatic alignment unit that moves the imaging optical system with respect to the eye to be examined based on a detection result of the alignment detection unit; and a focusing lens that is based on the detection result of the focus detection unit. A fundus camera, comprising: an autofocus unit that moves. The fundus camera according to claim 1, wherein the anterior eye portion of the eye to be examined is interposed via a fundus observation optical system having first imaging means for imaging the fundus oculi to be examined and an optical path branching member disposed in the optical path of the fundus observation optical system. An anterior ocular segment observation optical system having a second imaging unit for imaging, and the pupil / gaze detection unit is configured to detect at least one of a pupil state and a gaze direction based on an anterior segment image captured by the second imaging unit. A fundus camera characterized by detecting. 2. The fundus camera according to claim 1, wherein the detection of the pupil state by the pupil / line-of-sight detection means determines whether or not the pupil state is appropriate depending on whether or not a pupil edge is located outside a predetermined area centered on the imaging optical axis of the imaging optical system. A fundus camera characterized by detecting the eye. 2. The fundus camera according to claim 1, further comprising a fixation target optical system for presenting a fixation target to the eye to be examined, wherein the detection of the gaze direction by the pupil / gaze detection means is a presentation of the fixation target by the fixation target optical system. A fundus camera that detects whether or not the eye gaze direction is appropriate based on whether or not the center of the pupil is located within a predetermined area defined by the relationship with the position. 2. The fundus camera according to claim 1, wherein the observation optical system for observing the fundus of the eye illuminated by the illumination light source for observation and the detection results of the alignment detection means, focus detection means, and pupil / gaze detection means are both appropriate. Notification means for informing the examiner of the fact, and input means for the examiner to input a photographing permission signal, the automatic photographing means is the alignment detecting means after the photographing permission signal is inputted, A fundus camera that automatically performs photographing based on detection results of a focus detection unit and a pupil / gaze detection unit.

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