JP4393830B2 - Stereoscopic fundus observation device - Google Patents

Description

The present invention relates to a stereoscopic fundus observation equipment used to stereoscopically observe the fundus of the eye.

  In the ophthalmology field, devices such as a fundus camera for observing and photographing the fundus of a subject's eye have been widely used. In recent years, in order to grasp the state of the fundus in detail, an apparatus configured to perform observation and photographing three-dimensionally is also used. As such an apparatus, those disclosed in the following Patent Documents 1 and 2 are known.

  Patent Document 1 discloses the following invention. “An objective lens, an illumination light source that illuminates the eye to be examined through the objective lens, and a light beam splitter placed at a position conjugate to the pupil of the eye to be examined with respect to the objective lens, and the light flux that has passed through the objective lens Is divided into two along a vertical plane passing through the optical axis and stereoscopically observed in the stereoscopic fundus diagnosis apparatus, with respect to the vertical plane passing through the optical axis of the objective lens immediately before the light beam splitter, A fundus diagnosing device in which a pair of circular aperture stops are symmetrically arranged, and the distance between the aperture centers is variable, so that the stereoscopic observation baseline length can be arbitrarily set. "

  Patent Document 2 states that “an illumination optical system that illuminates the fundus, a two-hole aperture that divides the reflected light beam from the fundus, a reflecting unit that interchanges left and right light beams divided by the two-hole aperture, and a focusing lens. A pair of observation and imaging optical systems that respectively image the split light beams, and a fixation target is projected outside the fundus illumination area through a part of the illumination optical system in order to guide the fundus to be examined to a predetermined position. A stereoscopic fundus camera comprising: a fixation target projecting unit; and a moving unit that moves the fixation target in the optical axis direction in conjunction with the movement of the focusing lens of the observation photographing optical system.

Japanese Examined Patent Publication No. 56-020014 ([Claims]) Japanese Patent No. 297598 (claim)

  The devices described in these documents divide a reflected light beam from the fundus into two parts by a two-hole aperture and a light beam splitting prism arranged at a position optically conjugate with the pupil plane of the eye to be examined and divided into two. Since the three-dimensional image is taken by guiding the reflected light beams to the left and right independent photographing optical systems, it is necessary to provide the photographing optical systems separately on the left and right, which increases the size and cost of the apparatus.

  The apparatus described in Patent Document 1 is usually used with a binocular finder for stereoscopic observation of the fundus, but the examiner is often confused because the observed fundus image becomes an inverted image. In some cases, an erroneous description of fundus findings on the medical chart or an operational error when guiding the eye to be examined using a fixation lamp may occur.

  On the other hand, in the apparatus described in Patent Document 2, it is possible to observe the fundus image as an erect image, but it is necessary to dispose a reflecting means (light beam splitting prism) for switching the left and right light beams behind the two-hole aperture. Since this reflecting means is required to be designed, assembled, and adjusted with high accuracy in order to realize its action, it cannot be denied that there are problems in terms of cost and manufacturing.

The present invention has been made in view of such circumstances, and its object is to provide a suitably observable stereoscopic fundus observation equipment fundus of the stereoscopic image of the eye.

In order to achieve the above object, the invention according to claim 1 is directed to an illumination optical system that irradiates an illumination light beam for observing the fundus of the eye to be examined, and reflection of the illumination light beam from the illumination optical system by the fundus. a diaphragm two holes left and right of the opening is formed for passing a light beam, is opposed to the subject eye, through an objective lens, the left opening of the two-aperture stop for forming a focal point between the two-aperture stop The observation light beam formed by dividing the observation light beam into a left-eye observation light beam and a right-eye observation light beam and passing through the right opening of the two-hole aperture is left-eye observation light beam. An observation beam splitting unit that splits the observation beam for the right eye, and the observation beam for the left eye that is divided by the observation beam splitting unit after the observation beam that has passed through the left opening is shielded, and the right The observation light beam passing through the aperture of the observation beam splitting means And an observation optical system including an observation light flux shielding means for shielding said right eye observation light beam formed by more divided, the observation light beam passed through the aperture of the right, which are divided by the observation beam splitting means The observation light beam for the right eye is formed by guiding the observation light beam for the left eye to the left eye of the examiner and the observation light beam that has passed through the left opening is divided by the observation light beam dividing means. a three-dimensional fundus oculi observation device comprising the Turkey to allow the fundus of the three-dimensional observation by guiding Kukoto to.

  In order to achieve the above object, the invention according to claim 2 is the stereoscopic fundus oculi observation device according to claim 1, wherein the observation optical system switches the opening of the two-hole aperture alternately left and right. And further comprising a diaphragm shielding means for alternately emitting left and right observation beams. The observation light shielding means is for the left eye and right eye of the observation light beams emitted left and right alternately by the diaphragm shielding means. The observation light beam is alternately shielded in synchronization with the left and right switching of the observation light beam by the stop shielding means.

  In order to achieve the above object, a third aspect of the present invention is the stereoscopic fundus oculi observation device according to the second aspect, wherein the diaphragm shielding means and / or the observation light beam shielding means are arranged at an outer peripheral end. A disk-shaped shielding plate in which a plurality of notches for allowing the observation light beam to pass are formed at equal intervals, and the shielding plate is rotated at a constant speed so that the notch is placed on the optical path of the observation light beam for a certain time. And a driving unit that is controlled to emit the observation light beam intermittently by being arranged at intervals.

  In order to achieve the above object, the invention according to claim 4 is the stereoscopic fundus oculi observation device according to claim 1, wherein the observation optical system is disposed immediately before the left and right openings of the two-hole aperture. A pair of left and right first polarizing filters that are arranged and have polarization axes orthogonal to each other, and the observation beam shielding unit is configured to transmit the observation beam for the left eye and the right eye divided by the observation beam division unit. It consists of a pair of left and right second polarizing filters arranged on the optical path and having mutually orthogonal polarization axes, and the polarization axis of the left first polarizing filter and the polarization axis of the right second polarizing filter are parallel to each other. The polarization axis of the first polarizing filter on the right and the polarization axis of the second polarizing filter on the left are arranged in parallel.

In order to achieve the above object, the invention according to claim 5 is the stereoscopic fundus oculi observation device according to claim 1, wherein the observation mode for observing the fundus and the photographing for photographing the fundus are taken. When switching to the observation mode, the illumination optical system irradiates an illumination light beam for observing the fundus to enable stereoscopic observation of the fundus and enters the photographing mode. When switched, the illumination optical system irradiates a photographing illumination beam for photographing the fundus and reflects the light from the fundus by alternately switching the opening of the two-hole aperture to the left and right. Stop illumination means for alternately emitting the imaging illumination light beam that has passed through the left opening and the imaging illumination light beam that has been reflected by the fundus and passed through the right opening, and the alternately emitted light. Respectively imaging medium for receiving the imaging illumination beams was, and further comprising a.

  In order to achieve the above object, a sixth aspect of the present invention is the stereoscopic fundus photographing apparatus according to the fifth aspect, wherein the aperture shielding means allows the photographing light flux to pass through an outer peripheral end. By rotating the shielding plate so that the notch is switched and disposed immediately before the left and right openings of the two-hole aperture, the imaging light flux is switched to the left and right. It is characterized by comprising a chopper mechanism including drive means for emitting light.

  According to the stereoscopic fundus oculi observation device according to claim 1, the observation light beam that has passed through the left opening of the two-hole aperture is projected only to the right eye of the examiner and has passed through the right opening by the observation light beam shielding means. The observation light beam is projected only on the left eye of the examiner. Here, since the reflected light beam from the fundus of the illumination light beam is reversed left and right at the focal point of the objective lens, the observation light beam that has passed through the left aperture is used to observe an accurate fundus image in binocular vision. It should be observed by the examiner's right eye, and the observation light flux that has passed through the right opening should be observed by the examiner's left eye. Therefore, according to the present invention, the examiner can observe a suitable fundus image in an accurate uneven state.

  According to the stereoscopic fundus oculi observation device according to claim 2, the diaphragm shielding means and the observation light beam shielding means work together to alternately detect the observation light beam that has passed through the left opening and the observation light beam that has passed through the right opening. Projected to the person. At this time, the right and left switching is performed at a speed that does not cause flickering in the fundus image, for example, about 60 times per second or more, so that the examiner can see the fundus image as if viewing with both eyes simultaneously. Can be observed.

  The stereoscopic fundus oculi observation device according to claim 3 shows a specific configuration example of the diaphragm shielding means and / or the observation light beam shielding means. According to the configuration of claim 3, the observation light beam passing through the aperture of the two-hole aperture is rotated by rotating a substantially gear-shaped shielding plate having notches formed at equal intervals on the outer peripheral end portion at a constant speed. It is possible to easily switch alternately between shielding / opening and switching between shielding / opening of observation light beams for left eye and right eye.

  According to the three-dimensional fundus oculi observation device according to claim 4, the observation light beam that has passed through the left opening of the aperture shielding means is polarized by the left first polarizing filter and divided into the left-eye and right-eye observation light beams. However, since the polarization axis of the left second polarizing filter that polarizes the left eye observation light beam is orthogonal to the polarization axis of the left first polarization filter, the left eye observation light beam is shielded. Therefore, the observation light beam that has passed through the left opening is projected only to the right eye of the examiner. Similarly, the observation light beam that has passed through the right opening is projected only to the left eye of the examiner. Thereby, the examiner can suitably perform fundus observation. In addition, according to the present invention, it is not necessary to provide a driving means in the chopper mechanism or a driving circuit for driving the liquid crystal shutter, so that the configuration becomes easy.

According to the three-dimensional fundus oculi observation device of the fifth aspect, it is possible to alternately emit the photographing light fluxes passing through the left and right apertures of the two-hole aperture, so that it is not necessary to provide the photographing optical system independently on the left and right. Therefore, the size and cost of the apparatus can be reduced.

According to the three-dimensional fundus oculi observation device of the sixth aspect, similarly to the configuration shown in the third aspect, the observation light flux passing through the left and right openings can be easily switched.

Hereinafter, the fundus camera according to an embodiment of the fundus observation equipment according to the present invention will be described with reference to the drawings.

[Configuration of optical system]
First, the configuration of the optical system provided in the fundus camera of the present embodiment will be described with reference to FIGS. 1 is a schematic side view of the optical system of the fundus camera, FIG. 2 is a specific configuration example of a perforated mirror and shielding means provided in the photographing optical system of the optical system, and FIG. 3 is an operation form of the shielding means. FIG. 4 is a schematic front view for explaining, FIG. 4 is a schematic side view and a schematic front view showing a specific configuration example and operation mode of the observation optical system of the optical system, and FIG. 5 is a specific configuration example of the observation optical system. And a schematic top view and a schematic front view showing its operation mode, respectively. Note that “front” individually indicates a direction when viewed from the examiner side.

  The fundus camera of this embodiment includes an illumination optical system 10 including various optical elements for irradiating an illumination light beam for illuminating the fundus of the eye E, and various optical elements for capturing a fundus image of the eye E. An imaging optical system 20 and an observation optical system 30 including various optical elements for observing the fundus image of the eye E to be examined are provided.

[Illumination optics]
As shown in FIG. 1, the illumination optical system 10 includes an illumination lamp 11 made of a tungsten lamp or the like that emits an observation illumination light beam, a photographing xenon lamp 12 that flashes the photographing illumination light beam, and an illumination lamp 11. The condenser lens 13 that condenses the emitted illumination light beam for observation, the condenser lens 14 that condenses the illumination light beam emitted by the photographing xenon lamp 12, and the optical paths of the observation and photographing illumination light beams are combined. An oblique half mirror 15, an illumination stop 16, which is arranged in a conjugate manner with the pupil P of the eye E to be examined and has a light shielding area described later, a relay lens 17, a reflection mirror 18, and a condenser lens 19. Has been. In FIG. 1, the optical path of the illumination light beam is indicated by a dotted line.

[Photographing optical system]
Next, the photographing optical system 20 will be described with reference to FIGS. The photographing optical system 20 includes a fundus photography film 20A and a CCD 20B as an image receiving element for displaying a fundus image on a photographing medium. Furthermore, the imaging optical system 20 includes an objective lens 21 that faces the eye E, a perforated mirror 22 provided with a two-hole aperture 40 described later, and a shield that blocks a reflected light beam from the fundus of the eye E. Means 23, a focusing lens 24 for focusing, a quick return mirror 25, an imaging lens 26 for imaging a reflected light beam from the fundus on the film 20A, a quick return mirror 27, and the eye E A focusing screen 28 arranged in a conjugate manner with the fundus and a TV lens 29 for forming an image of a reflected light beam from the fundus on the CCD 20B are provided. In FIG. 1, the optical path of the reflected light beam from the fundus is indicated by a solid line. The objective lens 21 forms a focal point F between the objective lens 21 and the perforated mirror 22.

  The perforated mirror 22 is inclined with respect to the optical axis (imaging optical axis) O of the imaging optical system 20 at a position conjugate with the pupil P of the eye E, and the optical path of the illumination light beam from the illumination optical system 10 And the optical path of the reflected light beam from the fundus of the eye E to be examined. That is, the illumination light beam from the illumination optical system 10 is reflected in the direction of the eye E by the perforated mirror 22 and illuminates the fundus of the eye E through the objective lens 21.

  FIG. 2 shows an enlarged configuration of the perforated mirror 22 and the shielding means 23. FIG. 3 shows the operation mode of the shielding means 23. Here, as shown in each drawing of FIG. 3, the shielding means 23 is configured to be rotatable, and FIGS. 3 (A), 3 (B), and 3 (C) show the forms of the rotation. Show. In addition, although the shielding means 23 is rotating counterclockwise in the figure, the rotation direction may be a clockwise direction.

  As shown in FIG. 2, an opening 22 a for allowing the reflected light beam to pass is formed at the center of the perforated mirror 22. Further, a two-hole aperture 40 is provided in the opening 22 a of the perforated mirror 22. As shown in FIG. 3, the two-hole aperture 40 has two openings 40a and 40b arranged on the left and right. Therefore, the reflected light beam from the fundus of the eye E to be inspected is a pair of light beams composed of the light beam that has passed through the opening 40a and the light beam that has passed through the opening 40b. Hereinafter, when the reflected light beam is used for fundus photographing, it is called a photographing light beam, and when it is used for fundus observation, it is called an observation light beam. )

  Here, although illustration is omitted, a light shielding region is formed at the center of the illumination stop 16 of the illumination optical system 10. The illumination light beam passes through a passing area around the light shielding area and illuminates the eye E. The light blocking area of the illumination stop 16 is formed to a size that prevents the corneal reflection light of the illumination light beam from passing through the openings 40a and 40b of the two-hole stop 40, and prevents flare and ghost intervention by the corneal reflection light. (See Japanese Patent Publication No. 56-020014 by the present applicant).

  As shown in each drawing of FIG. 3, the shielding means 23 is a light shielding plate in which a plurality of rectangular cutouts 23a are formed at equal intervals on the outer peripheral end portion thereof. In other words, a plurality of light shielding portions 23 b that protrude in a rectangular shape at regular intervals are formed on the outer peripheral end of the shielding means 23. The shield means 23 is connected to a motor 50 (drive means) for rotating the shield means 23. The shielding means 23 is rotated by a motor 50 so that the notch 23a and the light shielding portion 23b are alternately arranged immediately before the openings 40a and 40b of the two-hole aperture 40. At this time, the light fluxes passing through the openings 40a and 40b pass through the notch 23a immediately before the openings 40a and 40b, and are shielded by the light shielding portion 23b. It will be emitted. The shielding means 23 shields both the pair of light beams as shown in FIGS. 3A and 3C, or alternately passes only one of the light beams as shown in FIG. 3B. A chopper mechanism configured to cause

  The focusing lens 24 is configured to be displaceable in the direction of the photographing optical axis O by driving means such as a pulse motor (not shown), and the control means described later adjusts and controls the amount of displacement to focus the fundus image. It is like that.

  The quick return mirror 25 performs an operation for switching between observation of the fundus of the eye E and imaging. Specifically, the quick return mirror 25 is configured to be able to switch between a state obliquely provided on the photographing optical axis O and a state retracted from the photographing optical axis O by driving means such as a motor (not shown). Yes. When observing the fundus of the eye E, the quick return mirror 25 is inclined on the photographing optical axis O and guides the observation light beam to the observation optical system 30. On the other hand, when photographing a fundus image, the quick return mirror 25 is retracted from the photographing optical axis O and guides the photographing light flux to the film 20A or the CCD 20B. Note that the switching of the arrangement state of the quick return mirror 25 is executed based on the control of the control means described later.

  In the present embodiment, the quick return mirror 25 is retracted from the imaging optical axis O during fundus imaging, and the imaging light beam travels straight, while the quick return mirror 25 is arranged on the imaging optical axis O during fundus observation. Although it is configured to reflect upward, a configuration opposite to this may be used depending on the arrangement of the optical system. Further, it is possible to make one light beam go straight and reflect the other light beam downward. Or it is good also as a structure which reflects both an imaging | photography light beam and an observation light beam, and guides them to each optical system.

  Further, the quick return mirror 27 performs an operation for switching between photographing the fundus image with the film 20A or the CCD 20B. For this purpose, the quick return mirror 27 can be switched between a state obliquely provided on the photographing optical axis O and a state retracted from the photographing optical axis O by a driving means such as a motor (not shown). Control is performed by a control means described later so that the image is taken in the latter state when shooting with 20A, and is placed in the former state when shooting with CCD 20B.

  Similar to the quick return mirror 25 for switching between photographing and observation, the reflection direction of the photographing light beam by the quick return mirror 27 can be appropriately designed according to the arrangement of the film 20A and the CCD 20B.

[Observation optics]
Subsequently, the observation optical system 30 will be described with reference to FIGS. 1, 4, and 5. As shown in FIG. 1, the observation optical system 30 includes an imaging lens 31 that forms an image of the observation light beam reflected in the vertical direction by the quick return mirror 25, and a prism that reflects the observation light beam from the vertical direction toward the examiner. 32, a light beam splitting prism 33 for dividing the reflected observation light beam into left and right observation light beams, shielding means 34 for shielding / opening the divided left and right observation light beams, and the distance between the pupils of the examiner (PD ) To reflect the left and right observation light beams in the horizontal direction, a focusing screen 36 conjugated with the fundus of the eye E, and an eyepiece 37 facing the eye E ′ of the examiner. ing. The observation optical system 30 is configured to share the objective lens 21, the perforated mirror 22, the two-hole aperture 40, the shielding means 23, the focusing lens 24, and the quick return mirror 25 with the photographing optical system 20. In FIG. 1, the reflected light beam from the fundus guided by the observation optical system 30 is indicated by a solid line.

  As shown in FIG. 5, the prism 35 (35L, 35R), the focusing screen 36 (36L, 36R), and the eyepiece lens 37 (37L, 37R) are each provided with a left (L) right (R) pair, and a light beam splitting prism. The left and right observation light beams divided by 33 are guided to the examiner's left eye E'L and right eye E'R, respectively. This pair of left and right optical systems constitutes a binocular viewfinder for the examiner, and the distance between the left and right viewfinders can be adjusted. Here, the observation light beam splitting prism 33 constitutes the observation light beam splitting means referred to in the present invention, and the observation light beam split into left and right thereby constitutes the left eye observation light beam and the right eye observation light beam according to the present invention, respectively. Yes.

  The shielding unit 34 can be configured as a chopper mechanism similar to the shielding unit 23 of the photographing optical system 20, for example, as shown in the schematic side view shown in FIG. That is, as shown in FIG. 4B, the shielding means 34 is configured as a light shielding plate in which two notches 34a and two light shielding parts 34b are formed at the outer peripheral end thereof, and is rotated by a motor 60 (driving means). It is designed to be driven. The shielding means 34 is rotated by the motor 60 so that the notches 34a and the light shielding portions 34b are alternately arranged immediately before the left and right emitting ends 33L and 33R from which the left and right observation light beams are emitted from the light beam splitting prism 33. . Therefore, the exit end 33L for the left observation light beam and the exit end 33R for the right observation light beam are alternately shielded so that the left and right light beams are alternately guided to the eye E 'of the examiner. That is, the shielding means 34 acts so that the fields of view of the left and right eyes E′L and E′R of the examiner are alternately in a shielded state / open state.

  Hereinafter, in order to discriminate between the shielding means 23 of the photographing optical system 20 and the shielding means 34 of the observation optical system 30, the former is referred to as the diaphragm shielding means 23 and the latter is referred to as the observation light beam shielding means 34. Further, the diaphragm shielding means 23 and the motor 50 that drives the diaphragm shielding means 23 may be referred to as diaphragm shielding means. Similarly, the observation light beam shielding means 34 and the motor 60 that drives the observation light beam shielding means 34 may be referred to as observation light beam shielding means.

[Control system configuration]
Next, the configuration of the control system of the fundus camera of the present embodiment will be described with reference to FIG. Each operation of the fundus camera is controlled by the control means 100 shown in FIG. The control means 100 is a microcomputer including an arithmetic control device such as a CPU and a storage device such as a RAM and a ROM. The control means 100 is provided with various circuits and devices according to the design and configuration of the fundus camera, such as driving means such as various motors and a power supply circuit for supplying power to the lamp of the illumination optical system. A control program is stored in a nonvolatile storage device such as a ROM of the storage device, and the fundus camera is operated when an arithmetic control device such as a CPU develops the control program on a main memory such as a RAM. The control unit 100 accepts operations from various operation units (not shown) by the examiner and appropriately executes a control program in accordance with the operations.

  The control means 100 includes an illumination lamp 11, an imaging xenon lamp 12, a motor 50 for rotationally driving the aperture shielding means 23 of the imaging optical system 20, and an observation light beam shielding means 34 for the observation optical system 30. The motor 60 and the CCD 20B of the photographing optical system 20 are connected. Here, as shown in FIG. 1, the image data of the fundus image captured by the CCD 20B is stored in the frame memory 200 based on the control of the control means 100, and is transmitted to the monitor 300 so that the image can be displayed. ing. The frame memory 200 and the monitor 300 may be provided in a fundus camera, or may be provided as an external device such as a computer capable of data communication with the fundus camera. Note that the monitor 300 constitutes a display device according to the present invention.

  Although not shown in the figure as a control system since it is a known configuration, a motor for driving the quick return mirrors 25 and 27 of the photographing optical system 20 and a motor for driving the focusing lens 24 are also included in the control unit 100. It is connected to and operates according to the control.

[Usage form]
According to the fundus camera having the configuration of the optical system and the control system as described above, the following fundus observation and fundus imaging can be performed.

[Usage pattern for fundus observation]
When performing fundus observation of the eye E, the examiner performs a predetermined operation to switch to the fundus observation mode. Upon receiving this operation, the control means 100 supplies power to the illumination lamp 11 to generate an observation illumination light beam, and also arranges the quick return mirror 25 on the photographing optical axis O so that the observation light beam is observed in the observation optical system. Lead to 30 side.

  In addition, the control unit 100 supplies power to the motor 50 and the motor 60 and performs control so that the diaphragm shielding unit 23 and the observation light beam shielding unit 34 are rotated in conjunction with each other. Specifically, the control means 100 switches between shielding / opening of the left and right openings 40a and 40b of the two-hole aperture 40 by the diaphragm shielding means 23, and the left and right observation light beam emitting ends 33L and 33R by the observation light beam shielding means 34. The rotation of the motor 50 and the motor 60 is controlled so as to synchronize with the switching of the shielding / opening.

  For example, the motor 50 is controlled to a rotational speed of about 8 rotations per second (or more). At this time, as shown in FIG. 3, the aperture shielding means 23 has eight cutouts 23a and light shielding portions 23b, so that the openings 40a and 40b can be shielded / opened at a speed of about 64 times per second. Can be switched. On the other hand, the motor 60 is controlled to a rotation speed of about 32 rotations per second (or more). Then, as shown in FIGS. 4 and 5, the observation light beam shielding means 34 is formed with two cutouts 34a and two light shielding portions 34b. Therefore, the emission ends 33L and 33R are similarly set to about 64 revolutions per second. Shielding / opening is switched quickly.

  Further, the control means 100 synchronizes the opening / shielding of the left opening 40a shown in FIG. 3 with the opening / shielding of the right emitting end 33R shown in FIG. 4 (A), and opens the right opening 40b. The rotation of the motors 50 and 60 is controlled so that the shielding and the opening / shielding of the left exit end 33L are synchronized. For this purpose, for example, the initial position of rotation of the motors 50 and 60 may be adjusted and controlled.

  Incidentally, as can be seen from FIG. 7 which is a schematic top view of the photographing optical system 20, the observation light beam PL to be observed with the left eye E′L of the examiner and the observation light beam PR to be observed with the right eye E′R. Is reversed left and right by the focal point F of the objective lens 21 and passes through the openings 40a and 40b of the two-hole aperture 40. That is, the observation light beam PL to be observed with the left eye E′L passes through the right opening 40b of the two-hole aperture 40, and the observation light beam PR to be observed with the right eye E′R passes through the left opening 40a. . Therefore, the examiner will recognize a fundus image in which the uneven state (steric effect) is reversed.

  However, according to the configuration of the present embodiment, the detection is performed by synchronizing the open state of the left opening 40a and the right exit end 33R and synchronizing the open state of the right opening 40b and the left exit end 33L. The observation light beam PL to be observed with the left eye E'L of the person can be guided only to the left eye E'L, and the observation light beam PR to be observed with the right eye E'R can be guided only to the right eye E'R. Therefore, it is possible to observe an accurate fundus image in a concavo-convex state. Note that although the fundus image is reversed up and down by the focus F, the left and right observation light beams are focused again at the positions of the focusing screens 36L and 36R. Therefore, the examiner can observe an accurate fundus image in an uneven state as an erect image.

  Further, the switching of the shielding / opening of the openings 40a and 40b of the double-hole aperture 40 and the switching / shielding / opening of the left and right observation light beam emitting ends 33L and 33R by the observation light beam shielding means 34 are performed about 60 times or more per second. Accordingly, fundus images are alternately projected on the left and right eyes E'L and E'R of the examiner alternately at a switching speed of about 60 times or more per second. By switching the projection of the fundus image to the left and right eyes E′L and E′R at such a high speed, it is possible to observe the fundus image without flickering (or with little). The speed of switching may be adjusted according to the visual ability of the examiner.

[Usage for fundus photography]
Next, a usage pattern when performing fundus imaging of the eye E will be described. When the examiner performs a predetermined operation for switching to the fundus photographing mode, the control means 100 receives this operation, retracts the quick return mirror 25 from the photographing optical axis O and moves the photographing light beam straight forward, and the film photographing mode. Alternatively, the arrangement of the quick return mirror 27 is switched according to the selection of the CCD shooting mode.

(In film shooting mode)
When the film photographing mode is selected, the control unit 100 retracts the quick return mirror 27 from the photographing optical axis O in order to guide the photographing light flux in the straight traveling direction (the direction of the film 20A). Further, the control unit 100 controls the motor 50 to rotationally displace the aperture shielding unit 23 to open one of the openings 40a and 40b (for example, 40a) of the two-hole aperture 40, and to flash the xenon lamp 12. The right fundus image is filmed by emitting light and projecting the right imaging light beam PR (see FIG. 7) onto the film 20A.

  In addition, after film shooting, the other opening 40b of the two-hole aperture 40 is opened based on the control of the control means 100, the xenon lamp 12 is flashed, and the left shooting light beam PL is projected onto the same film 20A. Thus, the left fundus image may be taken. In this way, by allowing continuous photography of the fundus, an ophthalmologist or the like diagnoses the eye E, or captures these two photographed images into a computer with a scanner and performs image processing, etc. This is suitable for forming an image.

(CCD shooting mode)
On the other hand, when the CCD photographing mode is selected, the control unit 100 places the quick return mirror 27 on the photographing optical axis O in order to guide the observation light beam downward (in the direction of the CCD 20B). Further, the control means 100 controls the motor 50 to rotationally displace the diaphragm shielding means 23 so that one of the openings 40a and 40b of the two-hole diaphragm 40, for example, the opening 40a is opened, and the xenon lamp 12 is turned on. The fundus image is photographed by the CCD 20B by flash emission (first photographing process). Image data of the fundus image captured by the CCD 20B is transmitted to the frame memory 200 and stored.

  Subsequently, the control unit 100 controls the motor 50 to rotationally displace the aperture shielding unit 23 to open the other opening 40b of the two-hole aperture 40, and the xenon lamp 12 is flashed to emit the fundus image. Is photographed by the CCD 20B (second photographing process). The image data of the photographed fundus image is similarly transmitted to the frame memory 200 and stored.

  The image data obtained by the first and second photographing processes stored in the frame memory 200 is transmitted to the monitor 300, and the two images are displayed in parallel. It should be noted that, when the parallel display is performed, an identifier (for example, “L”, which identifies whether these two images correspond to fundus images observed by the examiner's left eye E′L and right eye E′R, respectively) It is preferable to display “R” and the like at the same time.

  Here, in the first imaging process, imaging is performed based on the imaging light beam that has passed through the left opening 40a of the two-hole aperture 40, that is, the light beam PR that should be observed with the right eye E′R of the examiner. In the second photographing process, photographing is performed based on the photographing light flux that has passed through the right opening 40b, that is, the light flux PL to be observed with the left eye E′L of the examiner. Therefore, according to such a usage pattern, fundus images to be observed independently with the left and right eyes E′L and E′R of the examiner can be respectively taken. Furthermore, it is possible to display two captured images on the monitor 300 in parallel. In addition, by combining these images, it is possible to form and display a fundus image that accurately reproduces the uneven state.

  Here, the time interval between the first imaging process and the second imaging process can be set short. For this purpose, the control means 100 controls the motor 50 to rotate the aperture shielding means 23 at a predetermined speed, and the xenon lamp 12 is continuously operated twice in synchronization with the open states of the openings 40a and 40b of the two-hole aperture 40. Then, the image may be taken with the CCD 20B by flashing. Here, the rotation speed of the diaphragm shielding means 23 can be determined according to a time interval (for example, 50 ms) at which the xenon lamp 12 can continuously emit light. Thereby, it is possible to shorten the photographing time. Such a configuration is effective when imaging is performed by using a mydriatic agent to numb the movement of the pupil of the eye E to be examined.

  In addition, when the eye E undergoes miosis due to flash illumination in the first imaging process, it is preferable to perform imaging after the pupil diameter of the eye E has returned to its original state.

  In this embodiment, the shielding means (observation light beam shielding means) 34 of the observation optical system 30 is integrally formed on the left and right, but may be configured independently on the left and right. In this case, the control means 100 controls the left and right shielding means in conjunction with each other so as to shield / open the emission ends 33L and 33R according to the operation of the aperture shielding means 23.

  According to the fundus camera as described above, it is not necessary to provide a left and right imaging optical system for stereoscopically capturing a fundus image, and stereoscopic fundus imaging can be performed with a single imaging optical system. It is possible to reduce the size and cost. In addition, since the fundus image can be observed as an erect image, there is no inconvenience in description when writing the chart of the fundus findings or in operation when the eye to be examined is guided using a fixation lamp. Furthermore, since the reflecting means for switching the left and right light fluxes as described in the above-mentioned Patent Document 2 is not required, the problem of accuracy and the problem of cost due to this do not occur. In addition, two images captured by the CCD 20B can be displayed, and the images can be combined to form an accurate uneven three-dimensional image. Therefore, the image can be suitably used for diagnosis by an ophthalmologist or the like. Is possible.

[Modification of shielding means]
A description will be given of application possible variant for stereoscopic fundus observation equipment according to the present invention.

[First Modification]
First, a first modification using a liquid crystal shutter as shielding means will be described. The liquid crystal shutter is composed of a small liquid crystal display (LCD) that can transmit a light beam, and is configured to form, for example, a black region at a predetermined position of the display based on the control of the control means 100. This black area acts as a light shielding area for shielding the light flux. Therefore, the light beam is shielded by the light shielding region of the liquid crystal shutter and is transmitted through other regions.

  The liquid crystal shutter is provided as shielding means 23 and shielding means 34 of the optical system shown in FIG. A liquid crystal shutter (hereinafter referred to as a liquid crystal shutter 23) disposed as the shielding unit 23 is not shown in the figure, but according to the control of the control unit 100, a light shielding region is provided immediately before the openings 40a and 40b of the two-hole aperture 40, respectively. Is configured to form. That is, the liquid crystal shutter 23 switches between shielding / opening of the light beams passing through the openings 40a and 40b of the two-hole aperture 40, and acts so as to emit these light beams intermittently.

  Further, the liquid crystal shutter disposed as the shielding means 34 is composed of, for example, left and right independent liquid crystal shutters 34L and 34R as shown in FIG. The liquid crystal shutter 34L can form a light shielding region immediately before the observation light beam exit end 33L of the light beam splitting prism 33 under the control of the control means 100, and acts to switch the shielding / opening of the left observation light beam. Similarly, the liquid crystal shutter 34R can form a light shielding area immediately before the observation light beam exit end 33R of the light beam splitting prism 33 in accordance with the control of the control means 100, and switches the shielding / opening of the right observation light beam. Works. It should be noted that the left and right liquid crystal shutters may be integrally configured so that a light shielding region is formed immediately before the emission ends 33L and 33R.

  A usage pattern when such a liquid crystal shutter is used will be described. When performing fundus observation, the control unit 100 controls the liquid crystal shutter 23 to alternately form a light shielding region immediately before the left opening 40a and immediately before the right opening 40b. The switching speed of the left and right light shielding areas is about 60 times per second or more. Further, the control means 100 controls the liquid crystal shutter 34R to be in an open state when the (left side) opening 40a is in an open state, and the liquid crystal shutter 34L to be in an open state when the (right side) opening 40b is in an open state. To do. This makes it possible to observe an accurate fundus image in an uneven state as an erect image. At the time of fundus photographing, control is performed so as to form a left or right light-shielding region on the liquid crystal shutter 23 as in the case of the above embodiment.

  The shielding means 23 and the shielding means 34 need not have the same configuration. That is, the shielding means 23 can be a chopper mechanism and the shielding means 34 can be a liquid crystal shutter, or can be configured in the reverse manner. In any case, the control by the control means 100 is performed according to the above-described procedure.

[Second Modification]
Next, a second modification using a polarizing filter will be described. FIG. 9 shows a polarizing filter 123 arranged in place of the shielding means 23 shown in FIG. The polarizing filter 123 is provided with a left polarizing filter 123L disposed immediately before the opening 40a of the two-hole aperture 40 and a right polarizing filter 123R disposed immediately before the opening 40b. The polarizing filters 123L and 123R may be configured to be directly joined to the openings 40a and 40b or provided in the openings. The polarizing filters 123L and 123R constitute the first polarizing filter referred to in the present invention.

  FIG. 10 shows a left polarizing filter 134L and a right polarizing filter 134R arranged as the shielding unit 34 shown in FIG. The left polarizing filter 134L is disposed immediately before the observation light beam exit end 33L of the light beam splitting prism 33. Further, the right polarizing filter 134R is disposed immediately before the emission end 33R. That is, the left polarizing filter 134L and the right polarizing filter 134R have the same arrangement configuration as the liquid crystal shutters 34L and 34R shown in FIG. The polarizing filters 134L and 134R constitute the second polarizing filter referred to in the present invention.

  The left polarizing filter 123L and the right polarizing filter 123R have polarization axes in directions orthogonal to each other as indicated by arrows in FIG. Similarly, the left polarizing filter 134L and the right polarizing filter 134R have polarization axes in directions orthogonal to each other as indicated by arrows in FIG. Here, the polarization axis of the left polarizing filter 123L and the polarization axis of the left polarizing filter 134L are in a direction orthogonal to each other. In addition, the orthogonal axis of the right polarizing filter 123R and the polarizing axis of the right polarizing filter 134R are orthogonal to each other. Therefore, the polarization axis of the left polarization filter 123L and the polarization axis of the right polarization filter 134R are parallel, and the polarization axis of the right polarization filter 123R and the polarization axis of the left polarization filter 134L are parallel.

  According to the shielding means having such a configuration, the observation light beam that has passed through the left opening 40a of the two-hole aperture 40 is polarized in the polarization axis direction by the left polarizing filter 123L, and is emitted from the light beam splitting prism 33 through the optical system. The light is emitted from the ends 33L and 33R, respectively. The observation light beam emitted from the left emission end 33L is polarized in the direction of its polarization axis by the left polarizing filter 134L. At this time, since the observation light beam is already polarized in a direction orthogonal to the polarization axis of the left polarizing filter 134L, it is shielded by the left polarizing filter 134L. On the other hand, the observation light beam emitted from the right emission end 33R is polarized by the right polarization filter 134R, but the polarization axis of the filter 134R and the polarization axis of the left polarization filter 123L are parallel to each other, so that they are transmitted as they are. It becomes.

  The observation light beam that has passed through the right opening 40b of the two-hole aperture 40 is polarized in the direction of its polarization axis by the right polarizing filter 123R, and is emitted from the emission ends 33L and 33R of the light beam splitting prism 33 through the optical system. . The observation light beam emitted from the left emission end 33L is polarized in the direction of its polarization axis by the left polarizing filter 134L. At this time, since the polarization axis of the left polarization filter 134L and the polarization axis of the right polarization filter 123R are parallel, the observation light beam is transmitted as it is. On the other hand, the observation light beam emitted from the right emission end 33R is already polarized in the direction orthogonal to the polarization axis of the right polarizing filter 134R, and is thus shielded by the right polarizing filter 134R.

  According to the second modification using a polarizing filter, only the observation light beam that has passed through the right opening 40b of the two-hole aperture 40 is incident on the examiner's left eye E'L, and the examiner's right eye. Since only the observation light beam that has passed through the left opening 40a is incident on E′R, the examiner can observe an accurate fundus image in an uneven state as an erect image. Furthermore, according to the modified example, since it is not necessary to perform the left and right shielding state switching control by the control means 100 and it is not necessary to provide a means for driving the chopper mechanism or the liquid crystal shutter, the apparatus can be downsized. Cost reduction can be further promoted. Further, since the switching control of the shielding state is unnecessary, the examiner can perform normal binocular simultaneous observation, and can obtain a suitable observation image without flicker.

  In the above, the fundus camera for stereoscopically observing and photographing the fundus of the eye E has been described as a specific example. However, a stereoscopic fundus observation device for performing stereoscopic observation of the fundus and a stereoscopic fundus for performing stereoscopic imaging. The above-described configuration can be applied to the observation apparatus.

  The stereoscopic fundus oculi observation device according to the present invention can be configured using the illumination optical system 10 and the observation optical system 30 (including a shared part with the imaging optical system 20) in addition to the control system described above. According to such a three-dimensional fundus oculi observation device, an examiner can observe an accurate fundus image in an uneven state as an upright image. There is no confusion in operation when guiding the eye to be examined.

Further, the stereoscopic fundus oculi observation device according to the present invention can be configured using the illumination optical system 10 and the observation optical system 30, as well as the frame memory 200 and the monitor 300, in addition to the control system described above. According to such a three-dimensional fundus oculi observation device, images corresponding to the fundus image observed by the left eye and right eye of the examiner can be taken, respectively, and these two images can be displayed on the monitor in parallel. Is possible. It is also possible to form a stereoscopic image by combining these two images. Therefore, it can be suitably used for diagnosis by an ophthalmologist or the like.

  The configuration described above is merely an example of a configuration for carrying out the present invention. Therefore, all modifications, changes, additions, and the like can be made within the scope of the present invention.

  The configuration of the present invention can be used as appropriate for any stereoscopic observation apparatus and stereoscopic imaging apparatus for performing stereoscopic observation and / or imaging of an object. By utilizing the configuration of the present invention, it is possible to perform suitable stereoscopic observation and / or stereoscopic photographing of an object. Further, if the configuration of the present invention is used in a stereoscopic observation apparatus having separate left and right photographing optical systems, the apparatus can be reduced in size and cost.

It is a schematic side view showing the configuration of an optical system of a fundus camera which is an example of a stereoscopic fundus observation equipment according to the present invention. It is an enlarged side view showing a schematic configuration of a perforated mirror and a diaphragm shielding means disposed to the retinal camera which is an example of a stereoscopic fundus observation equipment according to the present invention. It is a diagram for explaining the operation mode of the stop shielding means disposed to the retinal camera which is an example of a stereoscopic fundus observation equipment according to the present invention. The diaphragm shielding means operates in order of FIG. 3A, FIG. 3B, and FIG. 3C along the time series. It is a diagram for explaining the observation light flux shielding means disposed to the retinal camera which is an example of a stereoscopic fundus observation equipment according to the present invention. FIG. 4A is a side view illustrating the outline of the configuration of the observation light beam shielding unit. FIG. 4B is a diagram for explaining an operation mode of the observation light beam shielding unit. It is a diagram for explaining the observation light flux shielding means disposed to the retinal camera which is an example of a stereoscopic fundus observation equipment according to the present invention. FIG. 5A is a top view schematically showing the configuration of the observation light beam shielding unit and the observation optical system. FIG. 5B is a diagram for explaining an operation mode of the observation light beam shielding unit. Is a block diagram showing the schematic configuration of a control system of the fundus camera which is an example of a stereoscopic fundus observation equipment according to the present invention. It is a schematic top view showing an optical path of the reflected light beam by the fundus of the eye structure and the illumination light beam of a main portion of the imaging optical system of the fundus camera which is an example of a stereoscopic fundus observation equipment according to the present invention. The configuration of a modification of the fundus camera which is an example of a stereoscopic fundus observation equipment according to the present invention is a schematic top view showing. The configuration of a modification of the fundus camera which is an example of a stereoscopic fundus observation equipment according to the present invention is a schematic diagram showing. The configuration of a modification of the fundus camera which is an example of a stereoscopic fundus observation equipment according to the present invention is a schematic diagram showing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Illumination optical system 11 Illumination lamp 12 Imaging xenon lamp 13, 14 Condenser lens 15 Diagonal half mirror 16 Illumination diaphragm 17 Relay lens 18 Reflection mirror 19 Condenser lens 20 Imaging optical system 20A Film (imaging medium)
20B CCD (shooting medium)
21 Objective lens 22 Perforated mirror 23 Shielding means (aperture shielding means)
24 focusing lens 25 quick return mirror 26 imaging lens 27 quick return mirror 28 focusing plate 29 TV lens 40 two-hole aperture 30 observation optical system 31 imaging lens 32 prism 33 beam splitting prism (observation beam splitting means)
34 Shielding means (observation beam shielding means)
35 (35L, 35R) Prism 36 (36L, 36R) Focus plate 37 (37L, 37R) Eyepiece

Claims (6)

An illumination optical system that emits an illumination light beam for observing the fundus of the eye to be examined;
An objective that forms a focal point between a two-hole aperture formed with left and right apertures through which the reflected light beam of the fundus of the illumination light beam from the illumination optical system passes and an eye to be examined. lens and the split observation light beams is formed passed through the left opening of the two-aperture stop to the observation light flux for observation light beam and the right eye left eye and the right opening of the two-aperture stop An observation beam splitting unit that splits an observation beam formed by passing into an observation beam for the left eye and an observation beam for the right eye, and the observation beam that has passed through the left opening is split by the observation beam splitting unit. An observation beam shielding unit that blocks the observation beam for the left eye, and that blocks the observation beam for the right eye formed by the observation beam splitting unit divided by the observation beam splitting unit. Optical system,
With
The observation light beam for the left eye, which is obtained by dividing the observation light beam that has passed through the right opening by the observation light beam splitting unit , is guided to the left eye of the examiner, and the observation light beam that has passed through the left opening is the observation device. stereoscopic fundus observation device comprising a Turkey to allow the fundus of the three-dimensional observation by guiding Kukoto the observation light flux for the right eye formed by splitting by the light beam splitting means to the right eye of the examiner. The observation optical system further includes a diaphragm shielding means that alternately switches the left and right apertures of the two-hole aperture and shields the aperture, and emits the observation light beam alternately left and right.
The observation light beam shielding unit synchronizes the left and right eye observation light beams of the observation light beam emitted from the left and right alternately by the diaphragm shielding unit in synchronization with the left and right switching of the observation light beam by the diaphragm shielding unit. The three-dimensional fundus oculi observation device according to claim 1, wherein the three-dimensional fundus oculi observation device is shielded alternately.   The diaphragm shielding means and / or the observation light beam shielding means includes a disc-shaped shielding plate in which a plurality of notches for allowing the observation light beam to pass through an outer peripheral end portion are formed at equal intervals, and the shielding plate is fixed. A chopper mechanism including drive means that is rotated at a speed so as to intermittently emit the observation light beam by arranging the notches on the optical path of the observation light beam at regular time intervals. The stereoscopic fundus oculi observation device according to claim 2. The observation optical system includes a pair of left and right first polarization filters that are disposed immediately before the left and right openings of the two-hole aperture and have polarization axes orthogonal to each other.
The observation light beam shielding means is disposed on an optical path of the left-eye and right-eye observation light beams divided by the observation light beam dividing means, and includes a pair of left and right second polarization filters having polarization axes orthogonal to each other. Become
The polarization axis of the left first polarization filter and the polarization axis of the right second polarization filter are arranged in parallel, and the polarization axis of the right first polarization filter and the second The three-dimensional fundus oculi observation device according to claim 1, wherein the three-dimensional fundus oculi observation device is arranged in parallel with a polarization axis of the polarizing filter. It is possible to switch between an observation mode for observing the fundus and a photographing mode for photographing the fundus,
When switched to the observation mode, the illumination optical system irradiates an illumination light beam for observing the fundus and enables stereoscopic observation of the fundus.
When switched to the photographing mode, the illumination optical system irradiates a photographing illumination light beam for photographing the fundus,
By switching the left and right apertures of the two-hole aperture alternately to be shielded, the photographing illumination light beam reflected by the fundus and passed through the left opening, and reflected by the fundus and passed through the right opening. Diaphragm shielding means for alternately emitting the illumination light beam for photographing,
An imaging medium that receives each of the illuminating illumination light beams emitted alternately, and
The stereoscopic fundus oculi observation device according to claim 1, further comprising: The diaphragm shielding means is configured such that the notch is switched and disposed immediately before the left and right openings of the two-hole diaphragm and a disc-shaped shielding plate in which a notch for allowing the photographing light beam to pass is formed at an outer peripheral end portion. 6. The stereoscopic fundus oculi observation device according to claim 5, further comprising a chopper mechanism including a driving means for switching the left and right to emit the photographic light flux by rotating the shielding plate.

Images