JPH0651026B2 - Eye examination device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention enables anterior ocular segment observation for aligning the eye to be inspected, and can guide the line of sight of the eye to be inspected during anterior ocular segment observation. The present invention relates to an eye inspection device.

[Prior Art] As a fundus camera capable of observing the anterior ocular segment of the subject's eye using the same observation finder in order to align the subject's eye, Japanese Patent Publication No. 52-48440 by the present applicant is known. Are known. This proposal will be described with reference to FIG. 4. Illumination light L from an illumination system (not shown) is a perforated mirror 1
The light is reflected on the left side and is directed to the left, and is incident on the eye E through the objective lens 2 arranged so as to face the eye E. The light flux reflected by the fundus Ef of the eye E to be examined is the objective lens 2
To the right, passes through the perforated mirror 1, and forms an image on the film surface 4 via the relay lens 3 provided behind it. A movable mirror 5 that can be raised and lowered is provided between the relay lens 3 and the film surface 4, and when the movable mirror 5 is inserted in the optical path, the reflected light is reflected upward and the light deflection mirror 6 is provided. To reach the finder eyepiece lens 7 via.

The image formation relationship between the fundus Ef and the pupil Ep in the fundus observing / photographing optical system will be described in more detail. In FIG. 4 (a), the illumination light L from the illumination system is the aperture 1a of the perforated mirror 1.
An image of the light source is once formed on the eye, and then further formed on the pupil Ep surface of the eye E to be examined through the objective lens 2 to prove the fundus Ef. When the device is in a proper position with respect to the eye E to be inspected, the pupil Ep is moved to the objective lens 2
An image is formed on the aperture 1a of the perforated mirror 1 by the. The examiner focuses the image of the fundus oculi Ef formed at the rear focal plane position R1 of the objective lens 2 on the film surface 4 by the relay lens 3 through the opening 1a of the perforated mirror 1. At that time, if the movable mirror 5 is inserted into the optical path, the light rays to be incident on the film surface 4 are reflected upward by the movable mirror 5, and further reflected by the mirror 6, and then at a position equidistant from the film surface 4. A fundus image is connected to R2 and can be observed through the eyepiece lens 7. At this time, perforated mirror 1
The opening 1a of 1 forms the entrance pupil of this optical system.

An auxiliary lens 8 is provided between the objective lens 2 and the perforated mirror 1.
Is inserted into and removed from the optical path. When observing the anterior segment of the eye, the auxiliary lens 8 is inserted into the optical path as shown in FIG. 4 (b). The same position R2 'where the image of the fundus Ef is formed by
An image of the pupil Ep is formed at. The pupil image formed at position R2 'is
It is observed by the examiner through the eyepiece lens 7 as in the case of FIG. 4 (a). Therefore, first, the auxiliary lens 8 is inserted into the optical path, the upper and lower sides and left and right sides of the pupil Ep are aligned by the eyepiece lens 7, and then the auxiliary lens 8 is removed from the optical path.
The fundus Ef is observed by the same eyepiece lens 7, and the movable mirror 5 is removed from the optical path to shift the projection to the film surface 4.

However, when observing the anterior segment for the purpose of this pupil alignment, it is not known where the subject should look, and accurate alignment of the optical axes of the subject's eye E and the fundus camera after this alignment cannot always be achieved. There is a problem.

Further, there is known a fundus camera in which the visual line of the eye E is fixed by inserting a visual target plate in a position conjugate with the fundus Ef of the eye E in the observation optical system. In this case,
The optotype plate 9 shown in FIG. 5 is arranged at a position conjugate with the position R2 shown in FIG. 4, and the light source is illuminated from behind.
This optotype plate 9 has two small holes 9 eccentric to the optical axis.
Depending on whether the eye E to be inspected is the left eye or the right eye, one of the two light sources is selectively turned on to illuminate the small hole 9a or 9b. That is, it is useful for diagnosis that the normally photographed fundus photograph is one in which the fixation point of the eye E to be examined is slightly decentered from the center of the screen. Small hole 9a
Alternatively, the light emitted from 9b is projected toward the fundus Ef of the eye E through the optical system shown in FIG.
Alternatively, the line of sight of the eye E is fixed by gazing at the image of 9b. However, in the optical system shown in FIG. 4 (b), the small holes 9a and 9b located at positions greatly decentered from the optical axis are provided.
Since the luminous flux emitted from cannot pass through the pupil Ep of the eye E to be inspected, it has a drawback that it cannot be used for visual line guidance during observation of the anterior segment.

JP-A-59-194729 is known as an improvement plan for these, and this known device is used at a position conjugate with the fundus of the eye to be inspected in the anterior ocular segment observing optical system during anterior ocular segment observation. By providing the second fixation target, the above-mentioned drawbacks are eliminated. FIG. 6 shows an example thereof, and the minute light source 10 is arranged at a position R which is substantially conjugate with the fundus oculi Ef in the auxiliary lens 8 in FIG. However, this light source 10 and the light source 10
Although the wiring cord 11 for supplying electric power to the eye is not conjugate with the anterior segment that is being observed, it causes an unpleasant shadow on the anterior segment image. In addition, fixation of the line of sight during observation of the anterior segment is less important than that during observation of the fundus. In other words, a fixation lamp disclosed separately in Japanese Patent Laid-Open No. 52-102029 is used for the final fixation of the line of sight of the eye to be inspected. Nevertheless, it is extremely uneconomical to form the second fixation target at a position completely different from that of the fixation target from the viewpoint of the configuration. It is more effective that the fixation target for anterior segment observation is provided at a position where a fixation target for fundus observation is provided, that is, at a position substantially conjugated with the anterior segment during anterior segment observation. Is.

[Object of the Invention] In consideration of the above points, an object of the present invention is that there is no inconvenience even when observing the anterior segment of the eye, and it is not necessary to make an uneconomical configuration. An object of the present invention is to provide an eye inspection device that can guide the line of sight.

[Summary of the Invention] The gist of the present invention for achieving the above-mentioned object is to provide a fundus observation optical system for observing a fundus of an eye to be inspected and a fundus observation optical system for performing alignment of the eye to be inspected. Focusing position variable means for observing the eye part, and optical index means provided at a position substantially conjugate with the anterior eye part in a state where the anterior eye part can be observed by the focus position changing means. The eye examination apparatus is characterized in that, in the observable state, the light flux emitted from the optical index means can substantially pass through a pupil of an eye to be inspected and reach a fundus.

Embodiments of the Invention The present invention will be described in detail based on the embodiments shown in FIGS. Incidentally, in FIG. 1, the components such as the projection optical system and the anterior ocular segment observation auxiliary lens 8 to which the same numbers as in FIG.

FIG. 1 (a) shows a state of observing the fundus Ef as in FIG.
(b) is a state in which the anterior segment is observed. In FIG. 1, a half mirror 20 is arranged in place of the optical path deflecting mirror 6 shown in FIG. 4, and a position equivalent to the position R2 with respect to the half mirror 20 behind the half mirror 20, that is, conjugate with the fundus Ef of the eye E to be examined. The optotype plate 21 is arranged at the position R3, and the fixation lamp 22 is provided behind it. The optotype plate 21 has three small holes 2 as shown in FIG.
1a, 21b, 21c, and the fixation lamp 22 has three LEDs 22a, 22b, 22c as shown in FIG.

The small holes 21a and 21b of the optotype plate 21 in this case have the same function as the small holes 9a and 9b shown in FIG. 5, but illuminate the small hole 21c at the center of the optical axis of the optotype plate 21. LED2
2c has its own lighting switch 23 as shown in FIGS. 1 (a) and 1 (b), and the switch 23 can be operated by the contact 8s attached to the auxiliary lens 8 only when the auxiliary lens 8 is inserted in the optical path. The LED drive circuit 24 is turned on and turned on. When the anterior ocular segment is observed with the auxiliary lens 8 inserted as shown in FIG. 1 (b), the pupil Ep and the position R3 are substantially conjugate to each other as described above.
The light flux emitted from the ED 22c and passing through the small hole 21c passes through the center of the pupil Ep and reaches the fundus Ef. Further, since this light flux is limited by the opening portion 1a of the perforated mirror 1, it is a light flux having a high directivity, and only a limited part of the fundus Ef is illuminated. Therefore, when the subject gazes at this light flux, the fixation of the line of sight of the eye E to be examined is almost achieved.

In the above embodiment, the LED 22c is turned on by the switch 23 using the contact 8s of the auxiliary lens 8. However, when the auxiliary lens 8 is inserted and removed by an electric means such as a solenoid, the LED 22c is turned on. May be lit in synchronization with the signal to the solenoid. Also,
What illuminates the visual target image is not limited to the LED, and the control of the lighting of each index is performed by the liquid crystal shutter or the like for the same light source without depending on the lighting of the LED.
It is obvious that equivalents to 1b and 21c may be formed and similarly controlled. Further, even if the small hole 21c is not completely on the optical axis, it is possible to decenter the small hole 21c within a range in which the pupil Ep of the eye E can pass, and the small hole 21c is set within the same range.
Alternatively, the small holes 21a and 21b may be individually provided and selectively turned on corresponding to the left and right eyes. Also,
Since the small hole 21c is on the same plane as the small holes 21a and 21b, in the state shown in FIG. 1 (a), the small hole 21c may act as a fixation target during observation of the fundus oculi Ef, like the small holes 21a and 21b. It is possible. This is extremely effective when photographing an abnormal position of the fundus.

[Effects of the Invention] As described above, the eye examination apparatus according to the present invention is provided with the light index means at a position substantially conjugate with the anterior segment of the eye, and arranged so that the light from the light index means reaches the fundus. Therefore, for example, when a fixation target for fundus observation is provided, it can be provided on the same surface as this and an effective configuration can be realized.

[Brief description of drawings]

1 to 3 show an embodiment of an eye examination apparatus according to the present invention, FIG. 1 is a configuration diagram thereof, FIG. 2 is a front view of an optotype plate, and FIG. 3 is a side view of a fixation lamp. FIG. 4 is a conventional configuration diagram, FIG. 5 is a front view of a conventional optotype plate, and FIG. 6 is a configuration diagram of a conventional fixation lamp. Reference numeral 1 is a perforated mirror, 2 is an objective lens, 6 is a half mirror, 8 is an auxiliary lens, 20 is a half mirror, 21 is a target plate, 21a, 21b and 21c are small holes, 22 is a fixation lamp,
22a, 22b and 22c are LEDs, 23 is a lighting switch, and 24 is an LED drive circuit.

Claims (2)

[Claims] 1. A fundus observing optical system for observing a fundus of an eye to be inspected, and a focus position changing means capable of observing an anterior segment by the fundus observing optical system for aligning the eye to be inspected. And an optical index unit provided at a position substantially conjugate with the anterior segment in a state where the anterior segment can be observed by the focusing position changing unit, and the light is emitted from the optical index unit in the observable state. An eye examination apparatus, characterized in that a light flux can pass through a pupil of an eye to be inspected and reach a fundus. 2. The eye examination apparatus according to claim 1, wherein the optical index means is provided on the same plane as a fixation target used when observing the fundus of the eye to be examined by the fundus observation optical system.