JP2612209B2 - Fundus camera - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fundus camera used for, for example, an ophthalmic clinic and performing fluorescence imaging.

[Prior Art] One of the imaging methods using a fundus camera is to look at when phleoessen, sodium, and the like injected from a vein reach the intraocular circulation system, and through an exciter filter provided in an illumination light path, to blue. There is a fluorescence imaging method in which a fundus is illuminated by excitation light of a system, fluorescence is generated from a blood column, and only the fluorescence is captured through a barrier filter provided in a capturing optical path.

In the state where the exciter filter and the barrier filter are inserted in the optical path, it is difficult to observe the fundus image due to insufficient light amount. It is necessary to remove the filter, and complicated operations such as selection of a fluorescence imaging mode, insertion of both filters during fluorescence imaging, and removal of a barrier filter during observation are required. Therefore, in order to facilitate this operation in the conventional fundus camera, the insertion and removal of the exciter filter and the barrier filter are motorized, and there are many erroneous operations of forgetting to insert the barrier filter at the time of photographing. There has been proposed a motorized fundus camera configured to insert both filters into an optical path.

[Problems to be Solved by the Invention] However, since the operation of the above-mentioned conventional retinal camera is extremely different from that of a non-motorized retinal camera, an examiner who is not accustomed to the electric retinal camera is required. On the contrary, there is a disadvantage that it is not easy to use.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fundus camera that is easy to use and can perform fluorescence imaging with simple switch operation without erroneous operation.

[Means for Solving the Problems] A fundus camera according to the present invention for achieving the above object has an illumination optical system for illuminating a fundus of a subject's eye, a photographing optical system for photographing a fundus image, and the illumination optical system. A first switch for selecting a fluorescence imaging mode in a fundus camera capable of performing fluorescence imaging having an exciter filter inserted into and removed from a system and a barrier filter inserted into and removed from the imaging optical system; And a second switch that is inserted into and removed from the photographing optical system, and provided independently of the second switch for performing photographing, and can be turned on / off by an operation independent of the second switch. A third switch,
A first step of inserting the exciter filter into the illumination optical system when the fluorescence imaging mode is selected by the first switch; and a state in which the fluorescence imaging mode is selected and the third switch is turned on. A second step in which the barrier filter is inserted into the photographing optical system regardless of the on / off state of the second switch in the state of the second step. The third switch is substantially in an off state. Filter control means for causing a third step of inserting / removing the barrier filter into / from the imaging optical system by turning on / off the second switch independently of the third switch at one time. It is characterized by the following.

[Function] In the fundus camera having the above-described configuration, the exciter filter is inserted when the fluorescence imaging mode is selected, and in the fluorescence imaging mode, the third camera for performing imaging regardless of the on / off state of the second switch. When the switch is turned on, the barrier filter is in the inserted state, and when the third switch is substantially turned off, regardless of whether the third switch is turned on or after turning on, the second switch is turned on / off. The operator can insert and remove the barrier filter at home.

[Example] The present invention will be described in detail based on an illustrated example.

FIG. 1 is a block diagram of the apparatus, in which an observation light source 1 is provided for illumination of the fundus, and a condenser lens 2, a photographing light source 3, and a condenser are provided on an optical path 01 from the observation light source 1 to the eye E to be examined. Lens 4, mirror 5, light shielding portions 6a and 6b shown in FIG.
Turret 7, a relay lens 8, a perforated mirror 9, and a wide-angle objective lens having a parallel flat plate 7a and an exciter filter 7b around a shaft 7c.
The fundus illumination optical system is configured by sequentially arranging 10 lenses.

On the other hand, as an imaging optical system, an aperture 11, a barrier filter 12 that can be inserted into and removed from the optical path 02, an imaging lens 13, a quick return mirror 14, and an imaging film 15 are arranged on an optical path 02 behind the perforated mirror 9. Further, a mirror 16 and an eyepiece 17 are sequentially arranged on an optical path 03 reaching the optometry e in the reflection direction of the quick return mirror 14 as an observation optical system.
The ring slit 6, the relay lens 8, the perforated mirror 9, and the stop 11 are conjugated with respect to the wide-angle objective lens 10.

The exciter filter 7b is called an excitation filter, and selectively transmits only the luminous flux in an excitation wavelength range suitable for exciting a fluorescent substance from white light, while the barrier filter 12 is called a transmission filter, and is a fundus reflection filter. From the light beam, only a light beam in a fluorescence wavelength region different from the excitation wavelength light is selectively transmitted.

Three switches for the examiner to operate the fundus camera,
That is, a mode changeover switch 18, a trigger switch 19, and a barrier filter insertion switch 20 are provided. The output from the mode changeover switch 18 is connected in parallel to a driving circuit 21, a strobe light emitting circuit 22, and an AND circuit 23.
The output of 21 is connected to a rotary solenoid 24, which is mechanically connected to the turret 7. On the other hand, the output from the trigger switch 19 is connected to a strobe light emitting circuit 22 and a one-shot pulse generator 25, and the output of the one-shot pulse generator 25 is connected to an AND circuit 23. The output from 23 is connected to an OR circuit 26, and the output of the OR circuit 26 is sequentially connected to a drive circuit 27 and a rotary solenoid 28,
The rotary solenoid 28 is mechanically connected to the barrier filter 12. The turret 7 is driven and rotated about an axis 7c by a rotary solenoid 24 so that the parallel plane plate 7a or the exciter filter 7b is selectively inserted into the optical path 01, while the barrier filter 12 is rotated by a rotary solenoid 28.
To be inserted into and removed from the optical path 02.

When used as a normal fundus camera, the mode switch 18 is turned off. In this state, the parallel flat plate 7a of the turret 7 is inserted into the optical path 01, and the barrier filter 12 is removed from the optical path 02. A light beam from the observation light source 1 for illuminating the eye E travels along the optical path 01, and is formed by the condenser lens 2, the photographing light source 3, and the condenser lens 4.
Is reflected by a mirror 5 through a ring slit 6, a parallel flat plate 7a of a turret 7, and a perforated mirror 9 via a relay lens 8, and reaches an eye E through a wide-angle objective lens 10. The light flux reflected by the fundus Ef returns to the same optical path, passes through the perforated mirror 9, travels on the optical path 02, passes through the aperture 11, the imaging lens 13, and passes through the quick return mirror 14 and the mirror 16.
And reaches the optometry e via the eyepiece 17.

After observing the eye E and aligning the same, the quick return mirror 14 is raised by operating a switch or the like (not shown), and the light source 3 emits light. Fundus photography can be performed. The light shielding portion 6a at the center of the ring slit 6 limits the area through which the light flux reflected by the fundus oculi Ef passes, and the light shielding portion 6b at the outer edge plays the role of restricting the fundus illumination light beam diameter. The image of the ring slit 6 is preferably formed on the pupil Ep, but may be formed between the vertex of the cornea Ec and the iris.

When performing fluorescent imaging, first select the mode switch
When only 18 is turned on, a high-level signal from the mode changeover switch 18 is output to the drive circuit 21, the strobe light emitting circuit 22, and the logic circuit 23, and the drive circuit 21 drives the rotary solenoid 24 to turn on the exciter filter 7b of the turret 7. Is inserted into the optical path 01 and the strobe light emitting circuit
At 22, the amount of light for fluorescence photography is adjusted. In this state, only the excitation light beam passing through the exciter filter 7b is
The examiner performs observation and alignment in the same manner as during normal fundus photography. When the barrier filter insertion switch 20 is turned on in consideration of the timing at which the fluorescent agent enters the blood clot, a high-level signal is output to the drive circuit 27 via the OR circuit 26, and the rotary solenoid 28 is driven by the drive circuit 27. When driven, the barrier filter 12 is inserted into the optical path 02. When the barrier filter 12 is inserted into the optical path 02, only the fluorescent light beam reaches the optometry e. Therefore, the optometry e turns on the trigger switch 19 while observing the timing while observing the fluorescence image of the fundus oculi Ef. And the strobe light emission circuit 22
To emit light to the imaging light source 3 to perform fluorescence imaging.

The eye E to be inspected during the fluorescence imaging by this series of switch operations
Is greatly shifted, the optometry e cannot observe the fluorescence image of the fundus oculi Ef, of course. However, since the barrier filter 12 is also inserted, it becomes impossible to grasp and observe even the position of the eye E to be examined. Therefore, it is necessary to temporarily turn off the barrier filter insertion switch 20 to remove the barrier filter 12 from the optical path 02. After the completion of the alignment, a series of operations for turning on the barrier filter insertion switch 20 and then on the trigger switch 19 is required. In order to simplify this operation and eliminate the risk of erroneous operation of failing to perform the fluorescence operation by forgetting to insert the barrier filter 12, in the case of the present embodiment, the AND circuit 23 and the one-shot pulse generator 25 are used. Used.

That is, once the trigger switch 19 is turned on, a pulse signal is output from the one-shot pulse generator 25 to the AND circuit 23 within a certain time. The logical product circuit 23 is turned on because a high level signal has already been input from the mode changeover switch 18, and the barrier filter 12 is inserted into the optical path 02 via the logical sum circuit 26 and the drive circuit 27. In other words, when the barrier filter insertion switch 20 is turned off and the trigger switch 19 is turned on, the insertion and the influence of the barrier filter 12 can be performed simultaneously, especially when the eye E is easy to move and the positioning is repeated. It is effective for

As shown in FIG. 3, it is convenient to provide a mode changeover switch 18 and a barrier filter insertion switch 20 in the switch section so that these operations can be performed from outside the fundus camera.

[Effects of the Invention] As described above, in the fundus camera according to the present invention, the exciter filter is inserted when the fluorescence imaging mode is selected, and the barrier filter is always inserted when the influence is performed by the third switch. Therefore, in the fluorescence imaging mode, the operation is facilitated, the erroneous operation of inserting and removing the filter is eliminated, and when the third switch is substantially off, the second switch is turned on regardless of before or after imaging. Since the operator can freely insert and remove the barrier filter by turning on / off, there is an advantage that even if the subject's eye is shifted during continuous imaging, the operation can be easily returned to the alignment operation.

[Brief description of the drawings]

The drawings show an embodiment of a fundus camera according to the present invention, FIG. 1 is a configuration diagram, FIG. 2 is a front view of a ring slit, and FIG. 3 is a front view of a switch unit. Reference numeral 1 is a light source for observation, 3 is a light source for photographing, 7b is an exciter filter, 12 is a barrier filter, 18 is a mode switch, 19 is a trigger switch, 20 is a barrier filter insertion switch, 21 and 27 are drive circuits, and 22 is a drive circuit. Strobe light emission circuit, 23
Is an AND circuit, 24 and 28 are rotary solenoids, and 26 is an OR circuit.

Claims (1)

(57) [Claims] An illumination optical system for illuminating a fundus of an eye to be inspected, a photographing optical system for photographing a fundus image, an exciter filter inserted into and removed from the illumination optical system, and a barrier inserted into and removed from the photographing optical system A first switch for selecting a fluorescence imaging mode, a second switch for inserting and removing the barrier filter in the imaging optical system, and performing imaging in a fundus camera having a filter and capable of performing fluorescence imaging. Therefore, a third switch which is provided independently of the second switch and can be turned on / off by an operation independent of the second switch, and a fluorescence imaging mode is selected by the first switch. A first step of inserting the exciter filter into the illumination optical system by the first step. The first step is performed when the fluorescence imaging mode is selected and the third switch is turned on. A second step in which the barrier filter is inserted into the photographing optical system irrespective of the on / off state of the second switch; a second step in which the third switch is substantially in an off state; Filter control means for functioning a third step of inserting / removing the barrier filter into / from the imaging optical system by turning on / off the second switch independently of the third switch. Fundus camera.