JPH04317626A - In-eye photographing system - Google Patents

Abstract

PURPOSE:To prevent the photographing error in advance by utilizing a film face-reflected light for the correct exposure control, and displaying a message at the time of abnormality, in the in-eye photographing system for photographing an eye to be examined. CONSTITUTION:Light reflected by a film 15 is photodetected by a photoelectric sensor 20, and its signal is integrated by an integrator 22, and compared with a light quantity value set in advance and decided by a comparison computing element 23 and a timer 27. As a result, when it is decided to be an error, a message is displayed on a television monitor 29.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intraocular imaging device that adjusts light by detecting light reflected from a film surface of imaging light.

0002

2. Description of the Related Art Hitherto, as an intraocular photographing device having a means for automatically adjusting light by detecting light reflected from a film surface of photographing light, there has been known, for example, the one disclosed in Japanese Patent Application Laid-Open No. 180935/1983. There is.

0003

However, in the above-mentioned conventional example, the light amount detection output is used only for determining the appropriate exposure amount, and therefore has the following drawbacks. That is,
When the subject's eye accidentally blinks, an error occurs when the eyelid closes and the light emission synchronizes (hereinafter referred to as a blink error), or an error occurs when the shutter installed in the film box, which opens only when shooting, does not synchronize with the light emission (hereinafter referred to as a synchronization failure). Errors) may occur on rare occasions.

[0004] Prevention of blinking errors is disclosed, for example, in Japanese Patent Application Laid-open No. 186539/1982, but it is necessary to detect observation light before photographing or to provide a separate detection means for proper exposure control. The disadvantage is that it must be used.

SUMMARY OF THE INVENTION An object of the present invention is to provide an intraocular imaging device that appropriately controls the exposure amount using a comparator and displays the result when an error occurs, in order to prevent the above-mentioned erroneous imaging. There is a particular thing.

[0006]

[Means for Solving the Problems] In order to achieve the above object, an intraocular photographing device according to the present invention includes a photographing illumination means for illuminating the inside of the eye to be examined, and a photographing illumination means for photographing the inside of the eye to be examined using the illumination means. means, a shutter that opens an aperture at the time of photography with a reflectance sufficiently lower than that of the photographic film, a photoelectric detection means that detects reflected light from the surface of the photographic film through the opening of the shutter, and a photoelectric detection means that detects light reflected from the photographic film surface through the opening of the shutter. In an intraocular imaging device that has an automatic light control means that stops emitting illumination light for imaging when the detected amount reaches a preset value, a timer circuit that is triggered when imaging starts, and a timer circuit that is activated by the timer circuit. The device is characterized by comprising a comparison calculator that compares and determines the relationship between time and the amount detected by the detection means according to preset judgment conditions, and a display unit that displays the comparison and determination results of the comparison calculator. .

[0007]

[Operation] The intraocular imaging device having the above-described configuration compares and determines the output of the appropriate exposure amount detection means in relation to a separately set time, and displays the result when an error occurs.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail based on the illustrated embodiments. FIG. 1 shows a configuration diagram of an embodiment of a non-mydriatic fundus camera. On an optical path O1 from an observation light source 1 that lights up a filament light bulb to emit a visible light flux to an eye E to be examined, there is a condenser lens 2, a visible light range a visible light cut filter 3 that blocks most of the light and transmits near infrared to infrared light, a photographic light source 4 consisting of a xenon flash lamp, a condenser lens 5, a mirror 6, a ring slit 7 having an annular closure,
A relay lens 8, a perforated mirror 9 having an opening in the center, and an objective lens 10 are arranged. The observation light source 1 and the visible light cut filter 3 are approximately conjugate with respect to the condenser lens 2,
The visible light cut filter 3 and the ring slit 7 are approximately conjugate with respect to the condenser lens 5, the ring slit 7 and the perforated mirror 9 are approximately conjugate with respect to the relay lens 8, and the perforated mirror 9 is approximately conjugate with respect to the relay lens 8.
The vicinity of the pupil of the eye E to be examined is substantially conjugate with respect to the objective lens 10. Also, on the optical path O2 behind the perforated mirror 9, a focusing lens 11, a photographing lens 12, a movable mirror 1
3. A shutter 14 and a film 15 whose surface has been treated to have a reflectance sufficiently lower than that of the film photosensitive surface are arranged in sequence, and on the optical path O3 in the reflection direction of the movable mirror 13, a field lens 16, an imaging lens 17, An infrared television camera 18 is arranged. An imaging lens 19 and a photoelectric sensor 20 are arranged diagonally below the film 15 in the reflection direction. The output of the photoelectric sensor 20 is connected to a comparator 23 via an amplifier 21 and an integrator 22. Comparison calculator 2
The output of 3 is sent to the light emission controller 25 via the stop signal generator 24.
It is connected to the. The output of the photographing signal generator 26, which is activated by an external photographing command, is connected to the light emission controller 25 and the timer circuit 27, the output of the light emission controller 25 is connected to the photographing light source 4, and the output of the timer circuit 27 is connected to the comparison calculator. It is connected to 23. Further, the output of the infrared television camera 18 is connected to a signal synthesizer 28, and the signal synthesizer 28 is connected to a comparator 23 and a television monitor 29.

During fundus observation, the near-infrared light and infrared light that pass through the visible light cut filter 3 out of the light beam from the observation light source 1 pass through the annular opening of the ring slit 7 and pass through the mirror of the perforated mirror 9. It is reflected by the surface and travels to the left along the optical path O1. Then, it enters the eye through the objective lens 10 from the outer periphery of the pupil of the eye E to illuminate the fundus Ef. The reflected light from the fundus Ef passes through the objective lens 10, the central opening of the perforated mirror 9, the focusing lens 11, and the photographing lens 12, is bent upward by the movable mirror 13, and is then reflected by the field lens 16 and the imaging lens 17. The light then reaches the infrared television camera 18. The television signal from the infrared television camera 18 passes through a signal combiner 28,
Displayed as a visible image on the television monitor 29, the examiner's eye
It can be visually recognized by Here, the shift in focus due to the difference in refractive power of the eye E to be examined is corrected by moving the focusing lens 11 in the optical axis direction.

When photographing, the movable mirror 1 is moved in response to a photographing command.
3 is removed from the optical path O2. Similarly, the light emission controller 25 turns on the photographing light source 4 in response to a signal issued from the photographing signal generator 26 when the shutter 14 is opened. This photographing light illuminates the fundus Ef of the eye E through the same optical path as the observation light, and the reflected light travels to the right and forms an image on the film 15 through the opening of the shutter 14, exposing the film 15.

The amount of light reaching the film 15 increases in accordance with the lighting time of the photographing light source 4, and as means for detecting the appropriate amount, a portion of the light reflected from the film surface is guided to the photoelectric sensor 20 via the imaging lens 19. The output of the photoelectric sensor 20 is sent to the amplifier 21
The signal is then sent to the integrator 22 via the comparator 23, and when the result is equal to the preset judgment condition, a signal is issued from the comparator 23 and sent to the stop signal generator 24, where the light emission stop signal is sent to the light emission controller. 25 to control the exposure to a proper state.

The integrated light amount output by the integrator 22 at this time is shown in FIG. Figure 2 shows the relationship between time and integrated light intensity, where L0 is the normal detection output, L1 is the abnormality detection output due to a blink error, L2 is the abnormality detection output due to a synchronization failure error, and L3 is the abnormality detection output due to the shooting light not being emitted. be.

In a normal case, a preset appropriate integrated light amount value S0 is reached at time t0. In this case, even if the difference in fundus reflectance and the difference in pupil diameter of the subject are considered, the time (t
Although S0 is reached within the time range of 0-α) or (t0+β), for example, even if the photographing light source 4 is turned on when the subject's eye E happens to have its eyelids closed, the blinking time will be several tens to several hundreds of meters.
2 seconds, the light emission of a xenon flash lamp is sufficiently short at several milliseconds, and the reflectance of the eyelids is sufficiently strong compared to that of the fundus, so it is shorter than time (t0-α) like L1. S0 is reached in a short time t1. That is, the time t1 counted by the timer circuit 27 triggered by the photographing signal generator 26 is changed to the time (t0-
α) or time (t0-
If it is predicted that S0 will be reached within a shorter time than α), the comparator 23 generates a character signal "BLINK" which means blinking as a result of the determination, and the signal synthesizer 28
The message is then displayed on the television monitor 29 as a message display.

Furthermore, if the shutter 14 does not operate according to the above-described operating procedure and does not open until after the photographing light source 4 is turned on, for example, if the shutter 14 does not open even after the lighting starts due to a mechanical catch, etc. Since the surface reflectance of the shutter 14 is treated to be sufficiently lower than that of the film, it does not reach S0 even after time (t0+β) as shown by the output line L2 in FIG. 2, and reaches the light amount value S2 at time (t0+β).

Furthermore, if the photographing light source 4 does not emit light due to its lifespan or other reasons, the time (t0
Even after +β), the light amount value becomes S3 due to extremely small amounts of external light. In order to determine these, the timer circuit 27
, and determines that the light amount value S0 is not reached even after the time (t0 + β), and furthermore, that the light amount value Sf that is lower than S0 is not reached. CHECK CAMERA” or “CHECK FLASH” message is displayed.

[0016] Note that the time that serves as the criterion for detecting blink errors is a time t, which is even shorter than the time (t0-α).
L may be set as the light quantity value Sc smaller than S0 as the light quantity serving as a criterion for detecting a synchronization failure error, and the time may be set as a time tH longer than the time (t0+β).

FIG. 3 shows a second embodiment using a mydriatic camera. In this case, the fundus camera section other than that shown in the figure uses the configuration shown in FIG. 1 except that the visible light cut filter 3 is removed. During observation, the fundus image using visible light is transferred to a movable mirror 13, a field lens 16, a mirror 31,
The examiner's eye e is directly viewed through the eyepiece 32. Also,
The message is displayed on a display 33 such as a light emitting diode array or a liquid crystal display at the fundus image formation position within the field of view of the subject e, that is, at the conjugate position of the film plane of the field lens 16. . Note that the display may be a sound display or the like that allows each state to be identified.

[0018]

Effects of the Invention As explained above, the intraocular photographing device according to the present invention has the detection output of the automatic light adjustment means that detects the light reflected from the film surface through the shutter opening. By comparing the light amount set value and time with the actual integrated light amount, and by displaying a message in the event of an abnormality, it is possible to immediately reshoot or check the machine in the event of a failure, without having to wait for the photographic film to be developed.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a first embodiment.

FIG. 2 is an explanatory diagram of the relationship between measurement time and integrated light amount in various states.

FIG. 3 is a configuration diagram of a second embodiment.

[Explanation of symbols]

1 Observation light source 4 Photography light source 13 Movable mirror 14 Shutter 15 Film 18 Infrared television camera 20 Photoelectric sensor 21 Amplifier 22 Integrator 23 Comparison calculator 24 Stop signal generator 25　Light emission controller 26 Photographing signal generator 27 Timer circuit 28 Signal combiner 29 TV monitor 33 Display

Claims (1)

[Claims] 1. Photographic illumination means for illuminating the inside of the eye to be examined; photographing means for photographing the inside of the eye to be examined using the illumination means; and a shutter for opening an aperture during photographing with a reflectance sufficiently lower than that of photographic film. , a photoelectric detection means for detecting light reflected from the photographic film surface through the opening of the shutter, and an automatic adjustment that stops emitting the photographic illumination light when the amount detected by the photoelectric detection means reaches a preset value. In an intraocular imaging device having an optical means, a timer circuit that is triggered upon the start of imaging, and a comparison in which a relationship between an elapsed time by the timer circuit and an amount detected by the detection means is compared and determined based on preset judgment conditions. An intraocular photographing device comprising a computing unit and a display means for displaying a comparison determination result of the comparison computing unit.