JP2844458B2 - Fundus observation device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a fundus oculi observation device capable of three-dimensional observation. [Prior Art] A method of performing three-dimensional observation of the fundus is described in, for example, Japanese Patent Publication No. 56-200.
No.14, etc., a method of moving a pupil position using a simultaneous stereoscopic fundus camera or a normal fundus camera to photograph two photographs and observing them with a stereoscopic viewer (“Fundus photography in practice”, Mikuni , By Yaedoe: Kanehara Publishing). [Problems to be Solved by the Invention] However, the above-described conventional example has the following disadvantages. (1) Simultaneous stereoscopic observation fundus camera: a. For stereoscopic observation, separate entrance pupils for left and right eyes must be provided, and a large entrance pupil is required. Therefore, stereoscopic observation can be performed only with the subject's eye that can sufficiently pupil. b. For the same reason, it is difficult to perform stereoscopic observation with a wide angle of view. c. For the same reason, when the camera is panned to photograph the periphery of the fundus, the entrance pupil is shaken by the subject's eye pupil, and sufficient stereoscopic observation cannot be performed. d. It requires independent optical systems for the left and right eyes, and is used only for research because the equipment is complicated and expensive. (2) In the method based on pupil movement: a. Since photographs are used, immediate observation and diagnosis cannot be performed. b. Since the left and right images are captured at different moments, it is difficult to reliably capture the same part. Further, the stereoscopic photograph viewer is a special one for specialists, and stereoscopic observation is possible only when completely the same part is photographed. For this reason, if the left and right images are shifted and not at the same site, the correction is extremely difficult and stereoscopic vision becomes impossible. However, the eye to be examined is always moving, and it is difficult to completely photograph the same site even when the eye is sufficiently fixed. [Object of the Invention] An object of the present invention is to solve the above-described drawbacks of the conventional apparatus, and to easily obtain a stereoscopic image using a fundus camera that performs stereoscopic observation by a pupil movement method, and An object of the present invention is to provide a fundus oculi observation device capable of observing a normal fundus image in response. [Summary of the Invention] The gist of the present invention to achieve the above object is to provide a single image capturing unit that captures a fundus image as an electric signal, and an image capturing unit that captures a fundus image one by one by the image capturing unit. A switch, storage means for storing at least two fundus images obtained at different timings by the imaging switch and the image imaging means, projection means for projecting a fundus image, and projection means for projecting the fundus image. Mode switching means for switching the projection mode of the fundus image to be outputted, and projecting the two fundus images based on the output of the storage means so that the two fundus images are selectively incident on the left and right eyes of the examiner. Execution control means for executing a first mode and a second mode for projecting one fundus image on the projection means by switching the projection mode by the projection means in accordance with the mode switching means; Have It is characterized by that. [Embodiment of the Invention] The present invention will be described in detail based on the illustrated embodiment. FIG. 1 is a block diagram showing one embodiment of an optical system of the fundus oculi observation device. Reference numeral 1 denotes an illumination light source composed of a tungsten lamp or the like. Light emitted from the illumination light source 1 passes through a condenser lens 2. The light enters the mirror 3, is deflected there, and reaches the perforated mirror 6 via the ring slit 4 and the relay lens 5. Light incident on the perforated mirror 6 from this illumination optical system is transmitted to the perforated mirror 6.
Thus, the light is reflected in the direction of the eye E, irradiates the fundus oculi Ef of the eye E, passes through the original optical path, further passes through the perforated mirror 6, and reaches the observation optical system. An objective lens 7 is arranged between the perforated mirror 6 and the eye E to be examined, and an imaging lens 8 and a color television camera 9 are arranged behind the perforated mirror 6 along the optical axis. A controller 11 and an image memory 12 are connected to the color television camera 9 in the fundus imaging means 10 configured as described above, and the controller 11 is connected to a color television monitor 13, liquid crystal glasses 14, an imaging switch 15,
The mode switch 16 is connected. Light emitted from the illumination light source 1 in the fundus imaging means 10 passes through the opening 4a of the ring slit 4 via the condenser lens 2 and the mirror 3, is reflected by the perforated mirror 6, passes through the objective lens 7, and passes through the objective lens 7 to the fundus of the eye E to be examined. Lights Ef. Here, the ring slit 4, the perforated mirror 6, and the pupil of the eye to be examined are optically conjugate, and the illumination light beam and the photographing light beam are separated in the anterior segment of the eye E to form a good fundus image without flare. Utilized to gain. The reflected light from the fundus oculi Ef is guided to the imaging surface of the color television camera 9 via the objective lens 7, the aperture of the perforated mirror 6, and the imaging lens 8, and captures the fundus image as an electric signal. When the mode switch 16 is in the normal recording mode,
The output of the television camera 9 is guided to the color television monitor 13 via the controller 11, and the fundus image Ea is projected on the monitor 13 in real time. At this time, when the examiner presses the imaging switch 15, the video is stored in the first area of the image memory 12. Thereafter, when the mode changeover switch 16 is switched to the observation mode, the controller 11 reads out the recorded image from the first area of the image memory 12 and displays the image on the color television monitor 13 as a still image. A procedure for performing stereoscopic observation of the fundus oculi Ef using the present apparatus that performs such a basic operation will be described. First, the examiner sets the apparatus to the recording mode by the mode changeover switch 16 so that the fundus image can be seen well and slightly eccentric to one of the left and right directions of the subject's pupil, that is, the position of, for example, R in FIG. Then, the fundus imaging means 10 is aligned. Then, when the imaging switch 15 is pressed, the first fundus image is stored in the image memory 12.
In the first area. Next, the fundus imaging means 10 is aligned at a position opposite to the previous eccentric state, for example, at the position L in FIG. 2, and the imaging switch 15 is pressed in the same manner, and the second fundus image is stored in the second memory of the image memory 12. Store in the area. By the above operation, two images from different pupil positions required for observing the fundus oculi Ef three-dimensionally are stored in the image memory 12. Thereafter, when the mode changeover switch 16 is switched to the stereoscopic observation mode, the controller 11 alternately reads the two images from the image memory 12 and alternately displays them on the color television monitor 13. At the same time, a driving signal synchronized with the alternate projection is issued to the prepared observation liquid crystal glasses 14 to alternately shield the left and right lenses of the liquid crystal glasses 13 from light. When the examiner wears the liquid crystal glasses 14 and observes the screen of the color television monitor 13, the fundus images captured at the positions L and R in FIG. 2 alternately enter the left and right eyes of the examiner. , And the fundus oculi Ef can be stereoscopically observed. If this device is used, stereoscopic observation of the fundus oculi Ef is basically possible, but as described above, another drawback of the method using pupil movement, that it is difficult to photograph the same site, remains as it is. I can say The improvement of this point will be described below. If two images on the left and right are photographed without paying special attention, the fundus of a slightly different portion is naturally stored in the two areas of the image memory 12 depending on the fixation state of the eye E to be inspected. The image is stored.
When it is projected on the color television monitor 13 as it is, Ea (L) for the left eye in FIG. 3 (a) and Ea for the right eye in (b)
The state is as shown in FIG. That is, 2 is alternately projected on the color television monitor 13.
The center OL and OR of the nipple of the image are eccentric by Δx and Δy with respect to the frame 13a of the monitor 13 or the frame AM of the aperture mask provided as appropriate, based on one of them.
Simply as it is, if the examiner observes via the liquid crystal glasses 14, the frame AM of the color television monitor 13 or the aperture mask becomes superior as a fusion stimulus, and it becomes difficult to stereoscopically view the fundus image. In addition, regarding the vertical deviation of Δy, the fusion limit is extremely low, so that even a small amount of Δy makes stereoscopic vision impossible. In order to avoid this, the relative position of the two images may be changed so that, for example, the right-eye image is positioned from Ea (R) in FIG. 3 (b) to Ea (R) ′ in (c). However, this has the advantage of the present apparatus that two images are recorded as electric signals, and this can be achieved by relatively inexpensive means. The following is a description of an example in which the two images are moved two-dimensionally. However, considering the problem of fusion, since the movement in the vertical direction is more important, even one dimension in the vertical direction has a sufficient effect.
FIG. 4 is an explanatory view of the method.
Are schematically shown. I constitutes a memory area together with the part B in which the values of the image are stored. Normally, a predetermined number of readings are performed sequentially from the address (ml, nl) of the memory as indicated by a dotted line arrow. The image is projected on the same position as when the image was taken. If a predetermined number of read start addresses can be read from, for example, any (m2, n2) address, the relative position of the fundus image projected on the monitor 13 can be easily changed. . Considering usability at this time, it is desirable that the address can be specified in a binocular vision state using an external input device such as a joystick or a mouse. Further, fixation points F1, F2, F3 and F4 projected on the monitor 13 irrespective of the movement of the image are provided as shown in FIG. In addition to improving the efficiency of the above-described operation, the angle of convergence of the examiner is also fixed, so that stable stereoscopic observation is possible. Further, it is needless to say that it is desirable to be able to erase the fixation point when it is unnecessary. The method of alternate projection using the liquid crystal glasses 14 described above,
It is common to use a normal TV rate of 60 Hz and synchronize for each field of a TV image. However, in order to further improve the resolution, a method of performing each frame is used. It is conceivable to project four screens alternately with odd fields. In the case where synchronization is performed for each field, a means for synchronizing the synchronization signal of the television camera 9 with the input of the imaging switch 15 and reliably capturing the odd field and even field images into the image memory 12 should be added. is there. Further, for a research purpose or the like in which flickering of an image is a problem, a method of performing stereoscopic observation using two monitors 13a and 13b as shown in FIG. 5 may be adopted. In the above description, the procedure for obtaining two images over time in a relatively short time and performing stereoscopic observation of the fundus has been mainly described. Can be used for stereochronoscopy, and in this case, changes over time in the fundus can be grasped with extremely high sensitivity. [Effects of the Invention] As described above, the fundus oculi observation device according to the present invention stores at least two images over time using the fundus oculi image as an electric signal, and performs three-dimensional observation of the images, thereby providing a special imaging device. The three-dimensional observation of the fundus can be performed immediately without preparing the image, and the normal fundus image can be observed when required for alignment or the like.
If additional improvements are made, operability is further improved, and stable stereoscopic observation becomes possible.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of a fundus oculi observation device according to the present invention,
FIG. 2 is a diagram illustrating the configuration, FIG. 2 is a diagram illustrating alignment during stereoscopic imaging by a pupil movement method, FIG. 3 is a diagram illustrating relative movement of two images, FIG. 4 is a schematic diagram of a memory area, and FIG. FIG. 10 is a configuration diagram of another embodiment. 1 is a light source, 6 is a perforated mirror, 7 is an objective lens, 9
Is a color television camera, 11 is a controller, 12 is an image memory, 13, 13a and 13b are color television monitors, 14 is liquid crystal glasses, 15 is an imaging switch, and 16 is a mode switch.

Claims (1)

(57) [Claims] A single image capturing means for capturing a fundus image as an electric signal, an image capturing switch for capturing the fundus image one by one by the image capturing means, and a timing obtained by the image capturing switch and the image capturing means at different timings. Storage means for storing at least two fundus images; projection means for projecting a fundus image; mode switching means for switching a projection mode of a fundus image projected by the projection means; A first mode for projecting the two fundus images based on the output of the storage means to the projecting means so as to be selectively incident on the left and right eyes of the examiner; and projecting one fundus image to the projecting means. A fundus observation device comprising: an execution control unit configured to switch and execute the projection mode by the projection unit according to the mode switching unit.