JPS6029131A - Ophthalmic photographing apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ophthalmological photographing apparatus capable of performing fluorescent ophthalmological photographing.

Fluorescence fundus photography is known as a type of ophthalmology photography.
By timing the time when the fluorescent agent injected through the cubital vein reaches the intraocular circulation system, the fundus of the eye is illuminated with blue excitation light, and the green-yellow fluorescence emitted by the fluorescent agent in the blood vessels is photographed. It will be done. It takes about 10 seconds for the fluorescent agent to appear in the eye. At that time, an exciter filter having wavelength light transmittance characteristics as shown in A in Figure 1 is inserted into the illumination optical path, and a barrier filter with characteristics as shown in B in Figure 1 is inserted in the photographing optical path. It is necessary. However, when both the exciter filter and the barrier filter are inserted, the fundus image seen through the finder is almost invisible until the fluorescence starts to appear. and - were inserted into the optical path to take pictures. After the fluorescent image appears, a typical photographer leaves the pressure filter inserted in the optical path in order to observe and diagnose the fluorescent image, and then take pictures using the filter on the side of the fundus camera. Because this is done by taking the frame in and out, the fundus camera moves when the filter is inserted, causing the alignment to shift and making it impossible to take good photographs. Bu C1! ! ! There was a problem in that the appearance of the fluorescent light made it impossible to photograph the initial image of the fluorescence.

The object of the present invention is to provide an ophthalmological photographing device that allows filter operation to be carried out easily and reliably and to obtain good fluorescence fundus photographs without misalignment. Explain.

FIG. 2 is a configuration diagram showing an example of the optical system of an ophthalmological camera. Reference numeral 1 indicates an observation light consisting of a tungsten lamp, etc. The light emitted from this tungsten lamp 1 is
The light enters a mirror 4 through a condenser lens 2a, a photographing light source 3 consisting of a xenon discharge tube, etc., and a condenser lens 2b, where it is deflected and sequentially passes through an exciter filter 5, a ring slit plate 6, and a relay lens 7a%7b. It is designed to reach hole opening Mitsu-8. In addition,
Reference numeral 9 denotes a reflecting mirror arranged behind the observation light source 1 to collect and reflect the light of this rung. The light incident on the perforated mirror 8 from the illumination optical system described above is reflected by the perforated mirror 8 in the direction of the subject [E], irradiates the fundus Ef of the subject's eye E, passes through the original optical path, and then returns to the perforated mirror 8. The light passes through the mirror 8 and reaches the observation optical system. An objective lens 10 is arranged between the perforated mirror 8 and the subject's eye E, and behind the perforated mirror 8, along the optical axis, there are a barrier filter 11, a focusing lens 12, a photographing lens group 13, A movable mirror 14, a shutter 15, and a photographic film 16 are arranged in sequence.

On the reflective side of the movable mirror 14, a field lens 17 placed at a position conjugate with the photographic film 16, a mirror 18 for changing the optical path, and a finder 19 are arranged in sequence along the optical axis. Note that e is the examiner's eye.

Here, the exciter filter 5 is inserted into the illumination optical path during fluorescence photography by driving the solenoid 21, and is removed from the optical path during other photography.

Further, the barrier filter 11 is inserted into and removed from the photographing optical path by driving a solenoid 20.

In this ophthalmological camera, the illumination light source 1 and the photographing light source 3 are substantially conjugate with respect to the condenser lens 2a, and the observation light υ 1 is turned on during observation, and the photographing light source 3 is turned on instantaneously during photography.

The light source image is once formed near the Schilling slit plate 6 by another condenser lens 2b, and then by a relay lens 7a.
, 7b, an image of the ring-shaped opening of the ring slit plate 6 is formed in the vicinity of the perforated mirror 8, where the illumination light is reflected and travels to the left. Then, the object 11 to be examined is exposed to the objective lens lO.
After forming an image of the ring-shaped aperture near the crystalline lens El of E, the fundus Ef is illuminated.

The reflected light from the fundus Ef travels to the right and is once formed into an image by the crystalline lens El and the objective lens 10, then passes through the perforated mirror 8 and the photographing diaphragm (not shown), and is focused by the focusing lens 12 and photographing lens group 13. It will be imaged. At the time of observation, the fundus image is guided upward by the movable mirror 14 located at the solid line position and observed by the examiner's eye e through the finder 19. At the time of photography, the movable mirror 14 is rotated to the dotted line position, and the fundus image is The image is formed on the photographic film 16 via the opened shutter 15.

3, 4, and 5 are cross-sectional views of a grip frame 30 through which an examiner operates an ophthalmologic camera, and an operation button 31 is attached to the upper part of the grip frame 30 so as to be movable up and down. Operation button 31
A switch S2 consisting of three spring contacts Sa, Sb, and Se is provided below. Fig. 3 shows the state in which the operation button 31 is not pressed, Fig. 4 shows the switch S when it is pressed for 1/2 stroke, and Fig. 5 shows the state when the switch S is pressed for the full stroke.
It shows the conduction and non-conduction states between the two spring contacts Sa, Sb, and Sc.

FIG. 6 is a block circuit diagram for controlling the operation of this embodiment, and the same reference numerals as in FIGS. 2 to 5 indicate the same members. 40, 41, and 42 are power supplies for the solenoid 20, observation light source 11, and photographing light source 3, respectively. The switch S2 is located within the aforementioned gripping frame 30, and Sl is a switch operated by a relay 50. Reference numeral 51 denotes a flip-flop circuit which is a drive circuit for the relay 50, and when the signal line Li is short-circuited with R2, it becomes a set state jJ and drives the relay 50, and when the power supply 40 is turned off, it is reset and the relay 50 is activated. It operates to stop the drive of 50. S3 is relay 4
This is a switch activated by 4. A thyristor 45 and a unijunction transistor (hereinafter abbreviated as UJT) 46 are inserted into the circuit to turn on the observation light source 1, and a trigger circuit 4 to turn on the photographing light source 3.
7, a charging resistor 48 and a discharging capacitor 49 are provided.

Then, the fundus Ef is illuminated with light shown in characteristic A in FIG. A few seconds after injecting the fluorescent agent, wait until the fluorescent light is emitted from the fundus Ef, press the operation button 31 of the gripping frame 30 by 1/2 stroke as shown in FIG. 4, and press the switch S2.
When the contacts Sa and sb are brought into conduction, an excitation current flows from the power source 40 to the solenoid 20 in FIG. 6, energizing the solenoid 20 and inserting the barrier filter 11 into the photographing optical path.

At the same time, the relay 44 is also energized, the switch S4 is switched to the normally open NO side, and the time constant for turning on the UJT 46 is reduced from the time constant R1・C1 of the resistor/capacitor circuit to R1・R2・C1/(R1 + R2). Then, the timing at which the UJT 46 is turned on in the output waveform of the power supply 41 shown in FIG. 7 is moved from point a to point b, the thyristor 45 is turned on by the UJT 46, and the energization time of the thyristor 45 is changed from Ta shown in FIG. increases to Tb. Therefore, the amount of light from the observation light source 1 increases, and in this state it becomes possible to observe and photograph a fluorescent image.

However, before the fluorescent image appears on the fundus Ef, with the barrier filter 11 inserted, nothing can be seen as an observation image of the fundus Ef, and it is necessary to correct the camera's positional deviation and defocus in order to take good pictures. I can't. In this case, when the user releases the operating button 31, the operating button 31 returns to the state shown in Fig. m3 due to the return force of the spring contact of the switch S2. In this state, the contacts Sa and Sb of the switch S2 are not electrically connected to each other, the excitation current to the solenoid 20 is cut off, and the barrier filter 11 is removed from the photographing optical path. At the same time, the excitation current of relay 44 is also cut off, and switch S3
switches to the normally closed NC side, and the time constant for turning on the UJT46 is R1 and R2・Ci/(R1+R2
) to ■ζ1・C1, and in Fig. 7, UJT4
The timing at which thyristor 6 is turned on moves from point b to point a, the energization time of thyristor 45 also decreases from Tb to Ta, and the amount of light from observation light source 11 decreases.

Since the fundus Ef can be observed in this state, it is possible to adjust the positional shift and focus shift.

When the camera has been corrected, press the operation button 31 of the gripping frame 30 again by 1/2 stroke as shown in FIG. 4 to bring the contacts Sa and sb of the switch S2 into conduction.
It becomes possible to observe and photograph the fluorescent image of the fundus Ef.

Now, for fluorescence photography, by pressing the operation button 31 a further 1/2 stroke from the position shown in FIG. 4, as shown in FIG. 5, the contacts sb and Sc of the switch S2 become conductive, and the trigger circuit 47 (g strings Ll and L2 are short-circuited, the amount of charge in the discharging capacitor 49 is released, and the photographing light source 3 emits light instantaneously. This completes the first photographing, but at the same time, the flip-flop circuit 51
transitions to the set state and drives the relay 50. As a result, the contact Sla of the switch S1 is connected to the normal oven N
When switched to the o side, the circuit connected to S18 is constantly short-circuited to L2, energizing the solenoid 20, and continuously holding the barrier filter 11 in the photographing optical path regardless of the state of the switch S2.

Furthermore, the contact Slb of the switch S1 is also normally open N.
When switched to the o side, the state of the Ll circuit depends on the contacts Sa and sb of the switch S2, that is, the state in which the operation button 31 of the gripping frame 30 is pressed by 1/2 stroke as shown in FIG. A signal is output to the trigger circuit 47, and the photographing light source 3 is switched to emit light.

This facilitates the second and subsequent imaging operations.Although the above embodiments have described operations related to barrier filters, the same applies to exciter filters.

Furthermore, the exciter filter and the barrier filter may be integrally operated in the same manner.

In the above-described embodiment, a spring contact is used for the switch S2, but a magnet may be provided at the bottom of the operation button 31, or a reed switch may be used for the contacts Sa, Sb, and Sc.

As described above, according to the present invention, after the first photograph is taken during fluorescence photography, the exciter filter and/or the barrier filter are held in the optical path, so that the second and subsequent photographs can be carried out efficiently.

[Brief explanation of the drawing]

FIG. 1 is a characteristic diagram of an exciter filter and a barrier filter, FIG. 2 and the following diagrams show an embodiment of an ophthalmological photographing apparatus according to the present invention, FIG. 2 is a configuration diagram thereof, and FIG. 3 is a sectional view of a gripping frame.
Figures 4 and 5 are diagrams for explaining its operation, Figure 6 is a block diagram of the operating circuit, and Figure 7 is a diagram for explaining the operation of the observation light source. In the figures, 1 is the observation light source, 3 is the photographing light, and 5 is the Exciter filter, 8 is a perforated mirror, 10 is an objective lens, 11 is a barrier filter, 14 is a movable mirror, 16 is a photographic film, 19 is a finder, 20.21 is a solenoid, 30 is a gripping frame, 31 is an operation button, 50 is a relay, 51 is a flip-flop circuit, and 5ISS2 and S3 are switches. Applicant Canon Co., Ltd.

Claims (1)

[Claims] Fluorescence ophthalmology imaging is possible by inserting an exciter filter into the illumination optical path and a barrier filter into the imaging optical path. In normal operation, the exciter filter and/or barrier filter The photographing device has an operating means for returning the valve to the outside of the optical path after the filter is inserted into the optical path, and detects that the first photograph has been taken and removes the filter inserted into the copying optical path. An ophthalmological imaging device characterized by having means for holding within an optical path. 2. The operating means has a two-stroke operation, and t'l
With the first stroke, insert the four filters into the photographic optical path, and with the second stroke, insert the four filters so that they illuminate the photographing light source.
The ophthalmologic imaging apparatus according to claim 1, wherein the imaging light source emits light in a first stroke after the first imaging is performed. 3. The holding means has a flip-flop circuit, and is set in a set state by the first photographing.
The ophthalmologic imaging device described in Section 1.