JP2001340301A - Ophthalmography - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform three-dimensional ophthalmography and monocular photography at the same time by a relatively simple constitution using a single apparatus. SOLUTION: A perforated mirror 2 has a perforation 20 for monocular photography, the iris 21 provided in concentric relation to the perforation 20, a perforation 22 for three-dimensional photography and the diaphragm 23 thereof formed thereto and, corresponding to a photographing mode, the perforated mirror 2 is laterally moved so that the perforations 20 and 22 coincide with an optical axis. The diaphragm 23 for three-dimensional photography of the perforated mirror 2 is conjugated with a light deflecting prism and the luminous flux from the diaphragm 23 is deflected in both lateral directions by the light deflecting prism.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fundus photographing apparatus used in an ophthalmic hospital, for example.

[0002]

2. Description of the Related Art Conventionally, simultaneous stereoscopic fundus photography and monocular photography have been performed using separate fundus cameras.

[0003]

However, in the above-mentioned conventional example, there is an uneconomical necessity of requiring two kinds of fundus cameras.

An object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide a fundus photographing apparatus capable of photographing a fundus of both a stereoscopic and a monocular simultaneously.

[0005]

A fundus photographing apparatus according to the present invention for achieving the above object comprises a light splitting member provided at a conjugate position of an anterior segment of an objective lens to split a fundus illumination light beam and a photographing light beam; A photographing lens that forms a fundus image by the objective lens, a field-of-view limiting member that is detachably provided at a position of the fundus image by the photographing lens, and a condenser lens that collects a light beam provided behind the field-of-view limiting member A light deflecting member provided in the optical path behind the condenser lens so as to be freely inserted and removed to deflect the light beam to the left and right, and an imaging lens for forming an image of the light beam deflected by the light deflecting member on a photographing surface. Features.

Further, a fundus photographing apparatus according to the present invention comprises a light dividing member provided at a conjugate position of an anterior segment of an objective lens to divide a fundus illumination light beam and a photographing light beam, and a photographing lens for forming a fundus image by the objective lens. And an optical system for forming a fundus image by the photographing lens on a photographing surface, wherein a monocular photographing diaphragm and a stereoscopic photographing diaphragm are switchably provided at a conjugate position of the light splitting member.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on the illustrated embodiment. FIG. 1 is a configuration diagram of an embodiment of the present invention, and shows an optical system of a fundus photographing apparatus capable of performing simultaneous stereoscopic fundus photographing and monocular fundus photographing. On the optical path O1 in front of the subject's eye E, an objective lens 1, a perforated mirror 2, which is arranged at a conjugate position of the anterior segment of the subject's eye E, a focus lens 3, a photographing lens 4, and as shown by thin lines during stereoscopic photography. A field stop 5 inserted into the optical path O1, a field lens 6, a collimator lens 7 at which a fundus image of the field lens 6 is positioned at a front focal point thereof, an optical deflecting prism 8 inserted into the optical path O1 and deflecting a light beam left and right during stereoscopic imaging; An imaging lens 9 and imaging means 10 having sensitivity to visible light and infrared light are sequentially arranged,
An imaging optical system is configured.

An optical path O2 in the direction of incidence of the perforated mirror 2 is an illumination optical system, and a condenser lens 12 reflects an infrared light beam and transmits visible light from a strobe light source 11 for photographing toward the perforated mirror 2. A dichroic mirror 13, a ring slit 14 conjugate with the pupil, a light blocking member 15 inserted near the ring slit 14 during stereoscopic imaging, and a relay lens 16 are arranged. Further, the condenser lens 17 and the infrared LE are provided in the incident direction of the dichroic mirror 13.
A light source 18 made of D is provided.

FIG. 2 shows a perforated mirror 2 as viewed from the optical axis direction. A hole 20 for monocular photography, a diaphragm 21 provided concentrically with the hole 20, a hole 22 for stereoscopic photography, and the diaphragm 23 are formed. The holes 20 and 22 are used by being moved in the horizontal direction so that the holes 20 and 22 are on the optical path O1 according to the shooting mode.

FIG. 3A shows a fundus image obtained by monocular photographing on the imaging means 10, and FIG. 3B shows a fundus image obtained by stereoscopic photographing. By inserting the light shielding member 15 into the optical path O2 during stereoscopic imaging, the optical axis light shielding portion of the ring slit 14 expands horizontally. The field stop 5 shields both sides of the field of view at half the center. The light polarizing prism 8 deflects so as to horizontally separate one half of the field of view. Since the fundus luminous flux is a parallel luminous flux between the collimator lens 7 and the imaging lens 9, even if the light deflecting prism 8 is inserted, the image plane does not tilt. The light deflecting prism 8 is an achromatic prism so that chromatic aberration does not occur. Focus lens 3
Although the parallelism breaks depending on the position of, it is made to be parallel at 0 diopter. If the refractive error is large, the parallelism is lost and the image plane is tilted, but since the field of view is narrow in the horizontal direction, the one-sided blur does not stand out.

If the collimator lens 7 is a convex lens having a light-collecting property, the one-sided blur can be reduced by that much without making parallel light. The aperture 23 for stereoscopic imaging of the perforated mirror 2 is moved by the field lens 6 to the focus lens 3 on the fundus of the standard vision.
Is conjugated with the light deflecting prism 8 at the position, and the light deflecting prism 8 deflects the light beam from the diaphragm 23 to both lateral sides.

In place of the light deflecting prism 8, a stereoscopic mirror 24 can be used as shown in FIG. The mirror 24 has a raised ridge 24a in the horizontal center, and the optical path O
When the optical path O1 is inclined at 45 degrees with respect to 1, the optical path O1 is bent by 90 degrees due to its reflection. The light beam reflected by the mirror 24 is separated and deflected right and left at an angle of one half of the viewing angle. The light beam is imaged on the imaging means 10 by the imaging lens 9. In addition,
For monocular photographing, a flat mirror (not shown) may be used and replaced with the stereoscopic photographing mirror 24.

FIG. 5 shows another embodiment of the photographing optical system. A photographing lens 31, a field stop 34 composed of a monocular stop 32 and a three-dimensional stop 33, and a lens 35 are provided on an optical path O1 behind a perforated mirror 30. An aperture stop for monocular photography, an aperture stop for stereoscopic photography 37, an optical deflecting prism 39,
A photographic lens 40 and an imaging unit 41 are arranged.

The perforated mirror 30 is provided with one hole on the optical axis, no photographing aperture is provided, and the hole is a hole 22 shown in FIG.
It is slightly widened as well as. The front focal point of the taking lens 31 is located in the pupil image of the objective lens near the perforated mirror 30. That is, the light beam from the pupil becomes parallel light behind the taking lens 31. The fundus conjugate field stop 34 is configured so that the monocular stop 32 and the stereoscopic stop 33 are interchanged. In addition, a wide monocular aperture 32 is connected to the optical path O.
1 and the three-dimensional aperture 33 may be configured to be inserted and removed in the vicinity thereof. Alternatively, it is also possible to configure so that both members of the stop 34 can be moved in the lateral direction to change the field of view.

The anterior focal point of the lens 35 is located at the conjugate of the ocular fundus. A light deflecting prism 39 having the same function as the light deflecting prism 8 is attached to the stereoscopic photographic stop 37 of the photographic stop 38, and the photographic stops 36 and 37 and the light deflecting prism 39 are interchanged according to the photographic mode. I have. The taking lens 35 has the same focal length as the lens 40, and the distance between their principal points is twice the focal length. Shooting aperture 38
Is intermediate between these lenses 35 and 40 and is conjugated to the pupil. In the case where the fundus image of the field stop 34 is emmetropia, the fundus image of the field stop 34 is formed on the imaging means 41 at the same magnification.

When focusing the fundus image, the imaging means 41 and the field stop 34 are moved integrally in the optical axis direction. Imaging means 4
When focusing is performed on the first imaging surface while viewing the fundus image by the imaging means 41, the field stop 34 also forms an image on the imaging surface. Since this photographing optical system does not include the focus lens 3 shown in the embodiment of FIG. 1, the positions of the ring slit 14 and the photographing stop 38 in the optical axis direction are always constant.

FIG. 6 shows still another embodiment of the photographing optical system. On the optical path O1 behind the perforated mirror 50, an imaging lens 51, a field lens 52, a rotary shutter 54 rotated by a motor 53, an aperture plate 56 driven by a solenoid 55, an imaging lens 57, and an imaging unit 58 are arranged. Have been.

In this embodiment, it is possible to perform substantially simultaneous three-dimensional imaging although it is not complete simultaneous three-dimensional imaging. The fundus image formed by the objective lens 1 is formed near the field lens 52 by the photographing lens 51, and the image is formed on the imaging unit 58 by the image forming lens 57. Focusing of the fundus image is performed by moving the imaging lens 57 or the imaging unit 58. Shooting lens 5
The pupil image near the perforated mirror 50 is formed on the diaphragm plate 56 by the field lens 1 and the field lens 52.

FIG. 7 is a front view of the rotary shutter 54 and the diaphragm plate 56 in this case as viewed from the optical axis direction. The rotary shutter 54 is rotated by a motor 53, and the rotary shutter 54 has an arc-shaped notch at the outer edge. An arc-shaped opening 60 is provided on the inner side near the center 59, and an arc-shaped opening 61 is provided between the notch 59 and the opening 60. The diaphragm plate 56 is rotated by a predetermined angle by a solenoid 55. The diaphragm plate 56 is provided with a monocular photographing stop 62 and a two-hole stereoscopic photographing stop 63, and the center of any one of them is positioned on the optical path O1 by the rotational driving of the solenoid 55. I do.

FIG. 7A shows the positional relationship during stereoscopic photography.
(b) shows the positional relationship during monocular imaging. The rotating shutter 54 is rotating during stereoscopic photography, and is stationary during monocular photography. In FIG. 7A, the aperture below the stereoscopic imaging aperture 63 overlaps the opening 60 of the shutter 54. At this time, the strobe light source 11 is caused to emit light, and the fundus image is captured by the imaging unit 5.
In step 8, the image is taken and the image is stored. Next, when the notch 59 of the rotary shutter 54 overlaps the upper stereoscopic shooting aperture 63,
The strobe light source 11 emits light again, and the image is stored.

When the rotating shutter 54 rotates at a speed of about 100 times per second, the photographing interval between them is less than that, so that the subject E can perform substantially simultaneous three-dimensional photographing with almost no problem in movement. When the two images obtained are observed with the left and right eyes, a stereoscopic image can be obtained. In addition, a stereoscopic image can be analyzed by calculation.

At the time of monocular photographing, as shown in FIG. 7B, the rotary shutter 40 is stopped so that the opening 61 is positioned in the optical path O1, and the diaphragm plate 56 is rotated so that the diaphragm 62 is positioned in the optical path O1. The strobe light source 11 moves through the aperture 62 to shoot an image. Since there is no moving lens such as the focus lens 3 between the perforated mirror 50 and the aperture plate 56, the conjugate relationship between the photographing aperture and the ring slit 14 does not change. The magnification of the fundus image is also changed by the imaging lens 57 behind the diaphragm plate 56.

[0023]

As described above, the fundus photographing apparatus according to the present invention can perform simultaneous stereoscopic fundus photographing and monocular photographing with a single apparatus with a relatively simple configuration.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a fundus imaging apparatus.

FIG. 2 is a front view of a perforated mirror.

FIG. 3 is an explanatory diagram of a monocular and stereoscopic imaging screen.

FIG. 4 is a perspective view of another light deflection member.

FIG. 5 is a configuration diagram of another embodiment of a photographing optical system.

FIG. 6 is a configuration diagram of still another embodiment of a photographing optical system.

FIG. 7 is a front view of a photographic stop of a rotary shutter viewed from an optical axis direction.

[Explanation of symbols]

1 Objective lens 2, 30, 50 Perforated mirror 5, 21, 23, 32, 33, 34, 36, 37, 3
8, diaphragm 10, 41, 58 imaging means 8, 39, light polarizing prism 54 rotating shutter 56 diaphragm plate

Claims (2)

[Claims] 1. A light splitting member provided at a conjugate position of an anterior segment of an objective lens to split a fundus illumination light beam and a photographing light beam, a photographing lens for forming a fundus image by the objective lens, and a fundus image by the photographing lens. A field limiting member provided removably at a position, a condenser lens provided behind the field limiting member for condensing a light beam, and a light beam left and right provided removably in an optical path behind the condensing lens. A fundus imaging apparatus comprising: a light deflecting member that deflects light; and an imaging lens that forms a light beam deflected by the light deflecting member on an imaging surface. 2. A light splitting member provided at a conjugate position of an anterior segment of an objective lens to split a fundus illumination light beam and a photographing light beam, a photographing lens for forming a fundus image by the objective lens, and a fundus image by the photographing lens. An optical system that forms an image on a shooting surface,
A fundus photographing apparatus, wherein a monocular photographing diaphragm and a stereoscopic photographing diaphragm are switchably provided at a conjugate position of the light dividing member.