JP3164234B2 - Stereoscopic fundus camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic fundus camera, and more particularly to a fixation lamp suitable for guiding a papilla of an eye to be examined.

[0002]

2. Description of the Related Art The applicant of the present invention has proposed, in Japanese Patent Application No. 2-188780, a stereoscopic fundus camera which separates a photographing light beam reflected by a fundus of a subject's eye into two right and left light beams to perform stereoscopic photographing. As the fixation index of this device, the fixation indices for the left and right eyes are fixedly arranged, and the fixation index is selectively presented to the examinee's eye by a selection switch for the left and right eyes. In addition, in the fundus camera for standard examination, in order to guide not only the nipple but also the macula in the same screen, the fixation indices for the left and right eyes are fixedly arranged, and the fixation indices for the left and right eyes are fixed. The visual indicator is selectively turned on. Furthermore, in this type of camera, a switch arranged in the center of the housing that houses the optical system detects whether the housing is on the left or right side with respect to the gantry, and based on this, fixation is performed A device for selecting lighting of an index is also known.

[0003]

However, in a stereoscopic fundus camera whose main purpose is to photograph the nipple and diagnose the temporal change of the nipple in glaucoma diagnosis, two luminous fluxes above the pupil are taken. Is required, so that the angle of view of the fundus is limited to about 30 degrees. Therefore, the macula is located at the periphery of the screen or outside the screen, and the installation position of the fixation lamp is not always in a position that is easy to see for the subject. In addition, since the eye to be examined moves its line of sight from the center of the apparatus to the fixation lamp, it is difficult to find the fixation lamp because it is dazzled by observation illumination light illuminated from the center of the apparatus. Therefore, the method of selectively presenting the fixation index of the conventional device is an example in which a fixation lamp is provided near the center of the device, and is not necessarily preferable.

Further, an apparatus having a mechanism for detecting whether the housing is on the left or right side with respect to the gantry by using a switch disposed at the center of the housing for housing the optical system is temporarily stopped by re-alignment or the like. when the switch is applied to the well, there is a fixation index to light is changed want UTO say problems.

An object of the present invention is to provide a stereoscopic fundus camera having a fixation lamp which is easy for a subject to visually recognize and easy for a photographer to use.

[0006]

In order to achieve the above object, a stereoscopic fundus camera according to the present invention has the following configuration. That is, (1) when observing the fundus of the eye to be examined , photographing with the observation illumination light flux
Sometimes an illumination optical system for illuminating a photographing illumination light beam, the
An optical system that is coaxial with the illumination optical system and a perforated mirror.
Splits the reflected light beam from the fundus of the eye into two light beams.
Observation / photography for observing and photographing the fundus image with each light beam
In stereoscopic fundus camera and a projection optical system, the photographing optical
At a position corresponding to the outside of the imaging field of the system and to the left of the optical axis
Place fixation indices for the left and right eyes at symmetrical positions to the right
The left and right fixation illuminating the mask plate and the fixation index of the mask plate
A visual illumination light source, upstream of the perforated mirror
Through the beam splitter obliquely placed in the optical path of the illumination optical system
A fixation target projection optical system that is coaxial with the illumination optical system, a selection unit that detects the left and right sides of the eye to be inspected and selects a fixation target to be watched , and a fixation target selected by the selection unit. The illuminating fixation light source that is illuminating causes the blinking to repeat,
Control means for keeping the fixation illumination light source lit ;
It is characterized in that it comprises.

[0007]

[0008]

[0009]

[0010]

[0011]

[0012]

[0013]

Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [Configuration] (Housing and Sliding Stand) FIG. 1 is a side view showing the overall configuration of the apparatus of the embodiment, and FIG. 2 is a partial front view showing a part of the internal structure.

Reference numeral 1 denotes a housing for housing optical systems such as an illumination optical system, a photographing optical system, and an observation optical system, which will be described later. The housing 1 is mounted on a horizontal moving base 2 via a support 3, and is vertically moved by turning an adjustment knob 4. 5,5 '
Are two linear motion rails provided on the horizontal moving table 2 and extending in the left-right direction (the direction orthogonal to FIG. 1) with respect to the eye to be examined. Each of the linear motion rails 5 and 5 'is supported by an intermediate support 7 via a plurality of slide rollers 6a and 6a', and the housing 1 placed thereon together with the horizontal moving table 2 is horizontally moved. Can relatively move in the direction of the subject's eye.

The intermediate support 7 further includes a slide roller 8
a and 8a ', are supported by two linear motion rails 10, 10' arranged on a gantry base 9. The linear motion rails 10, 10 'extend parallel to the subject's eye in the front-rear direction (the left-right direction in FIG. 1).
At the same time, the eye can be guided by the linear motion rails 10 and 10 'to move in the front-rear direction of the subject's eye with respect to the gantry base 9. Reference numeral 11 denotes an operation lever for operating the slide base, and the housing 1 is moved in the horizontal direction by the operation lever 11 to adjust the position with respect to the eye to be examined. 11a is a relay for fundus photography.
The switch is provided at the top of the operation lever 11.

As shown in FIG. 2, a micro switch 12 is mounted inside the horizontal moving base 2, and a switch corresponding to the switch piece 12 'of the micro switch 12 is provided inside the intermediate support 7. An uneven portion 13 for operation is formed. When the housing 1 is moved in the front-rear direction with respect to the subject's eye, the intermediate support 7 also moves with the horizontal moving base 2 with respect to the gantry base 9.
The horizontal moving table 2 moves only when moving in the left-right direction with respect to the subject's eye. For this reason, it is possible to detect the electrical position in the left and right eye directions by operating the switch piece 12 '.

Numeral 14 denotes a column mounted on the base 9 , numeral 15 denotes a subject, numeral 16 denotes a chin rest for placing the face of the subject 15 provided at an intermediate portion of the column 14, and numeral 17 denotes a column. Further, a forehead rest which is located above the head and fixes the head of the subject 15, 18 is a vertical movement knob capable of moving the support 14 up and down, 19 is an objective lens barrel, and 20 is a focusing knob. is there.

(Optical System) FIG. 3 is a schematic layout view of the optical system of this embodiment when viewed from the side, and FIG. 4 is a diagram of the optical system of FIG. 3 viewed from above. I. Illumination optical system 21 is a halogen lamp as a light source for observation, 22 is a condenser lens, and 23 is a xenon flash lamp as a light source for photographing. The halogen lamp 21 and the xenon flash lamp 23 are located at positions conjugate to the condenser lens 22.

Reference numeral 24 denotes a beam splitter, and 25 denotes a relay.
A lens 26 is an aperture stop. 27 is a mirror for changing the optical path, 28 is an illumination system relay lens, 29 is an illumination stop, 30 is a beam splitter, 31 is an illumination system relay lens, and 32 is a perforated mirror. The aperture stop 26 is formed of a ring-shaped slit, forms an intermediate image of the slit near the opening of the apertured mirror 32, and forms an apertured mirror-3.
After the light is reflected by the objective lens 2, a slit image is formed near the cornea by the objective lens 33, and the fundus of the subject's eye 34 is illuminated.

B. The imaging optical system 35 is a two-hole stop. The two-hole stop 35 is arranged so as to be conjugate with the pupil of the eye to be examined via the objective lens 33, and the two-hole stop 35 divides the light beam into two. Reference numerals 36 and 37 denote light beam splitting prisms. The light beam splitting prism 36 is for switching the left and right of the bisected light beam.

Reference numeral 38 denotes a relay lens, 39 denotes a focusing lens, 41 denotes an imaging lens, and 42 denotes a film surface. The light beam reflected by the fundus of the subject's eye forms an inverted intermediate image at point A by the objective lens 33, and then passes through the aperture of the perforated mirror 32, a two-hole aperture 35, a light beam separating prism 3
6 and 37, the film surface 42 is passed through a relay lens 38, a focusing lens 39, and an imaging lens 41.
To form a fundus image. By adjusting the focusing knob 20, the focusing lens 39 can be moved in the optical axis direction to adjust the refractive power of the eye to be inspected, and focus the fundus image on the film surface 42.

Reference numeral 40 denotes a flip-up mirror, which switches the optical path between the photographing optical system and the observation optical system, and is synchronized with the emission of the xenon flash lamp 23.
Is raised in the direction of the arrow, and at the same time, the lamp 23 emits light,
The luminous flux from the fundus is guided to the film surface 42. 33-4
Reference numeral 1 (excluding 40) constitutes a photographing optical system.

C. Observation optical system The reflected light from the fundus guided through the objective lens 33 to the focusing lens 39 is reflected by the flip-up mirror 40, and further changes the optical path by the mirror 43. The photographer 47 observes the fundus image of the eye through the observation system imaging lens 44, the ocular field stop 45, and the ocular lens 46.

D. The index optical systems 48 and 49 are light sources that project the mask 50. The mask 50 is configured as shown in FIG.
“b” is a fixation index for the left eye and the right eye for the subject to fixate. The fixation indices 50a and 50b are the light source 48,
The light source 48, 49 is turned on or blinks.

The mask 50 moves in the direction of the optical axis in conjunction with the focusing lens 39 to correct the refraction state of the eye. Reference numeral 51 denotes an auxiliary lens which is arranged so that the fixation index incident on the eye to be inspected does not change even when the mask 50 moves in the optical axis direction. That is, in the present embodiment, the auxiliary lens 51, the beam splitter 30, the illumination system relay lens 31, and the objective lens 33 constitute a Badard optical system, and the combined focal point of them is located at the pupil position. The index optical system is made coaxial with the illumination optical system by the beam splitter 30.

FIG. 6 is a view showing the field of view when the subject faces the objective lens 33. Reference numeral 52 denotes an illumination area limited by the illumination diaphragm 29. 53 is a fixation index for the left eye, 5
Reference numeral 4 denotes a fixation index for the right eye, and as described above, the fixation index 53 for the left eye and the fixation index 54 for the right eye are both turned on at the same time, and alternatively, they are blinked and presented. The fixation indices 53 and 54 are arranged at positions 15 degrees to the left and right and 2 degrees upward with respect to the imaging angle of view. At this time, the nipple can be brought to the center of the screen (see FIG. 7). Such a configuration of the mask is an example set for imaging mainly the nipple.

[Configuration] The operation of the above embodiment will be described. The chin of the subject 15 is placed on the chin rest 16, and the head is brought into contact with the forehead pad 17 to be seated. Then, the height is adjusted by the vertical movement knob 18 so that the subject's eye 34 can be substantially opposed to the objective lens barrel 19 of the fundus camera housing 1.

The halogen lamp 21 serving as a light source for observation of the optical system main body accommodated in the housing 1 is turned on to illuminate the eye 34 to be examined. Photographer operates back and forth and left and right sliding mechanism by the operation lever -11 further by adjustment knob 4 a housing 1 is vertically align the pupil of the slit image and the subject's eye 34 of the aperture stop 26 of the lighting system To align the optical system.
When the alignment is substantially completed, the fundus is illuminated with illumination light.

An instruction is given to watch the blinking side of the left and right fixation indices visible inside the apparatus. When the horizontal moving table 2 moves in the right eye direction, the switch piece 12 'moves following the unevenness of the intermediate support 7, and the microswitch is turned on / off. The signal from the microswitch is processed and input to a microcomputer (not shown), which controls the drive circuit of the light source 49 to blink only the right eye indicator 50b.

Next, fine adjustment of the alignment is performed while observing the fundus image. The reflected light from the fundus passes through the objective lens 33 and forms an intermediate image A. This fundus image is an inverted image. Thereafter, the light beam passes through a perforated mirror 32 and is split into two light beams on the left and right by a two-hole stop 35. The light beam split into two light beams is separated by the light beam splitting prism 36 by exchanging the left and right light beams. The separated light beam is a prism 37a,
After being reflected by b, the relay lenses 38a and 38b, the focusing lenses 39a and 39b, and the observation system imaging lens 44
An image is formed on the eyepiece field stops 45a and 45b by a and b. This fundus image is an erect image. The photographer can observe the image through the eyepieces 46a and 46b to perform stereoscopic observation of the fundus. The photographer observes the right and left fundus images, turns the focusing knob 20 interlocked with the focusing lenses 39a and 39b to adjust the focus to a position conjugate with the film surface 42, and simultaneously uses the illumination light for both the left and right images. Fine-tune the alignment to avoid flare.

After the alignment and focusing are completed,
When the photographing button is pressed, the flip-up mirror 40 in the photographing system jumps up in synchronization therewith, and the xenon flash lamp 23 emits light. When the xenon flash lamp 23 emits light, a fundus image is captured on the film surface 42. The above operation is controlled by a microcomputer (not shown) inside the apparatus except for a manual part. The fundus images photographed in this manner are a pair of stereo images as shown in FIG.

[0032]

Second Embodiment In the first embodiment, it is determined which side of the left and right eyes the horizontal movable base 2 is on from the on / off signal of the microswitch, and the blinking of the light source 48 or 49 is directly controlled by this. In the second embodiment, the light sources 48 and 49 are determined by determining which side the horizontal moving table 2 is on for a predetermined time continuously.
It is a device that controls the blinking of. For convenience of explanation, the apparatus of the first embodiment is used as it is except for the software of the microcomputer. FIG. 8 is a flow chart for controlling the blinking of the light source.
It is a chart. Only when the horizontal movable base 2 is on the left or right side continuously for a fixed time (for example, 1.5 seconds), a control signal for blinking the light source is sent.

In the initial state, the light source on the left eye side may always be made to blink, and a control signal for only switching the blinking direction may be given. With this configuration, blinking switching of the fixation index for temporary movement is prevented.

[0034]

According to the present invention, since the left and right fixation indices are presented together, the presence of the fixation indices can be easily recognized, and the blinking direction can be easily guided by blinking. In addition, it is possible to automatically select and set a fixation index at a predetermined position for the left and right eyes and blink the fixation index, which is excellent in a shooting operation.

[Brief description of the drawings]

FIG. 1 is a side view showing the overall configuration of an apparatus.

FIG. 2 is a partial front view showing a part of an internal structure.

FIG. 3 is a schematic layout diagram of an optical system when the present embodiment is viewed from the side.

FIG. 4 is a view of the optical system of FIG. 3 as viewed from above.

FIG. 5 is a diagram showing a mask configuration.

FIG. 6 is a diagram showing a field of view when a subject faces an objective lens.

FIG. 7 is a diagram showing a photographed fundus image.

FIG. 8 is a flowchart for controlling blinking of a light source.

[Explanation of symbols]

 Reference Signs List 7 Intermediate support body 12 Micro switch 12 'Switch piece 13 Concavo-convex part 26 Aperture stop 33 Objective lens 35 Two-hole stop 39 Focusing lens 40 Bounce mirror 45 Eyepiece field stop 50 Mask

Claims (1)

(57) [Claims] 1. An observation illumination light beam when observing a fundus of a subject's eye.
An illumination optical system for illuminating with an illumination light beam for imaging during imaging , and an optical system coaxial with the illumination optical system by a perforated mirror.
System that separates the reflected light beam from the fundus of the eye to be examined into two light beams.
Observation and photographing of the fundus oculi image by each split light beam
In stereoscopic fundus camera and a police-taking optical system, shooting
A position corresponding to the outside of the shooting field of the shadow optical system and
And fixate the left-eye and right-eye fixation indices
Left to illuminate the mask plate to be placed and the fixation index of the mask plate
A right fixation illumination light source, and
Beam splitter slanted on the optical path of the illumination optical system on the upstream side
A fixation target projection optical system that is coaxial with the illumination optical system via a lens, a selection unit that detects the left and right sides of the eye to be inspected and selects a fixation target to be watched , and a fixation selected by the selection unit The fixation illumination light source that illuminates the indicator blinks repeatedly,
Stereoscopic fundus camera, wherein a rectangular fixation illumination light source comprises a control means to remain lit, the.