JP2685239B2 - Ophthalmic equipment - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to ophthalmic devices.

(Prior Art) When observing or photographing a human eye, an ophthalmologic machine guides the illumination luminous flux of an illumination light source to the human eye through an optical system to illuminate the human eye, but an excessive amount of illumination light exceeding a certain limit. If the light is continuously applied to the human eye, the human eye will be damaged. The relationship between this human eye illumination light intensity and the time until this human eye illumination light intensity is continuously applied to the human eye to be damaged is known as the human eye illumination safety allowable accumulated light intensity curve A shown in FIG. ing. In FIG. 1, the horizontal axis represents the allowable illumination time t, the vertical axis represents the illumination light amount W, and the product Wt of these is the human eye illumination safe allowable accumulated light amount.

As is clear from the human eye lighting safety allowable accumulated light amount curve A, at an illumination light amount below a certain limit (illumination light amount a0 or less), the human eye is damaged even if it is illuminated for a virtually infinite time. I can't receive it. Here, “substantially” means the time required for observation and photographing using an ophthalmologic machine.

Conventionally, the human eye is illuminated by using the illumination light quantity below the certain limit (illumination light quantity a0 or less) for observation and photographing, or the human eye is illuminated for a very short time to perform photographing. Therefore, it is not necessary to further consider the human eye lighting safety allowable storage light amount curve A.

(Problems to be solved by the invention) However, when observing or photographing, a situation arises in which an excessive amount of illumination light above a certain limit (illumination light amount a0 or more) is continuously applied to the human eye, and observation or photography is desired. There is also. For example, with a fundus camera as an ophthalmologic machine, it may be desirable to perform ICG imaging during fluorescent fundus imaging, but this ICG imaging is weak because the amount of light at the excited wavelength is low and the TV camera's light receiving sensitivity is low. An excessive amount of illumination light exceeding a certain limit must be continuously applied to the eye, and the human eye may be damaged by the illumination.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an ophthalmologic apparatus capable of protecting the human eye when continuously giving an excessive illumination light amount above a certain limit to the human eye. There is a place to do it.

(Means for Solving the Problems) In order to achieve the above-mentioned object, an ophthalmologic apparatus according to the present invention has an illumination light source for human eye illumination, an illumination optical system that guides the luminous flux of the illumination light source to the human eye, and Illumination light amount detecting means for detecting the illumination light amount for the human eye, illumination light amount integrating means for integrating the illumination light amount detection output of the illumination light amount detecting means, light amount integrated output of the illumination light amount integrating means, and human eye illumination safety allowable accumulated light amount And an illumination light source control means for controlling the illumination light amount so as to protect the human eye when the integrated output of the light amount exceeds the human eye illumination safety allowable storage light amount.

According to the present invention, the illumination light amount detection output of the illumination light amount detection means is also integrated by the illumination light amount integration means, and the illumination light source control means is integrated with the illumination light amount integration output of the illumination light amount integration means and the human eye lighting safety allowance. The accumulated light quantity is compared, and the illumination light source is controlled so as to protect the human eye when the integrated light quantity output exceeds the human eye lighting safety allowable accumulated light quantity. Therefore, when an excessive amount of illumination light exceeding a certain limit is continuously given to the human eye, the illumination light amount is controlled by comparing the integrated output of the illumination light amount and the human eye lighting safety allowable accumulated light amount. Fluctuations in brightness,
Even if the amount of illumination light fluctuates due to changes in the characteristics of the optical elements that make up the illumination optical system, it is possible to reliably prevent damage to the human eye.

(Example) Hereinafter, an example in which the ophthalmologic apparatus according to the present invention is applied to a fundus camera will be described with reference to the drawings.

2 to 5 show a first embodiment of an ophthalmologic apparatus according to the present invention. In FIG. 2, 1 is an illumination optical system, 2 is a photographing optical system, and E is a human eye. The illumination optical system 1 has an illumination light source 3 for human eye illumination, a collimator lens 4, an exciter filter 5, a ring diaphragm 6, a half mirror 7, a total reflection mirror 8 and a perforated mirror 9. The illumination light source 3 is driven by the drive circuit 10. The drive circuit 10 is controlled by a control device 11 as an illumination light source control means, a safety amount comparison control circuit 12, and the control device 11 includes a gantry position detection switch 13, a barrier filter detection switch 14, and an inspected eye fixed position detection switch. 15 and a foot switch 16 are provided.

Does the gantry position detection switch 13 illuminate the left eye,
With a switch to detect whether the right eye is illuminated,
It is a switch that is turned on when a frame (not shown) is moved to a position corresponding to the left eye or the right eye. The barrier filter detection switch 14 is a switch that is turned on when the barrier filter 5 ′ of the photographing optical system 2 is inserted in the optical path of the photographing optical system 2. The inspected eye fixed position detection switch 15 is a switch that is turned on when the human eye is located at a predetermined position,
For example, a chin rest switch or a forehead rest switch is used as the inspected eye fixed position detection switch. The foot switch 16 is a switch which is provided at the foot and is turned on when stepped on.

As shown in FIG. 3, the gantry position detection switch 13 includes a right eye detection switch 17 and a left eye detection switch 18. The right eye detection switch 17 and the left eye detection switch 18 are input to the OR circuit 19, and the output of the OR circuit 19 is input to one input terminal of the 3-input AND circuit 20 and the other input terminal of the 3-input AND circuit 20. The outputs of the eye fixed position detection switch 15 and the barrier filter detection switch 14 are input. The 3-input AND circuit 20 has a function of outputting a switching signal to the ICG switching circuit 21 when all the outputs of the switches 13, 14, 15 are high (ON).

The ICG switching circuit 21 controls the drive circuit 10 so that the illumination light source 3 emits an illumination light amount of high illuminance above a certain limit, and the illumination light source 3 emits an illumination light amount of low illumination below a certain limit. It has a function of switching the drive circuit 10 between the normal mode in which the drive circuit 10 is controlled as described above. The foot switch 16 has a function of turning on / off the drive circuit 10.

Therefore, according to the control device 11, even if the foot switch 16 is inadvertently stepped on, the drive circuit 10 does not switch to the ICG mode unless the barrier filter 5'is inserted in the optical path of the photographing optical system 2. Therefore, damage to the human eye E due to careless operation can be prevented.

The illumination light flux of the illumination light source 3 is condensed by the collimator lens 4, and when the exciter filter 5 is inserted in the optical path, a light flux having a wavelength corresponding to the characteristic of the exciter filter 5 is guided to the ring diaphragm 6. The ring diaphragm 6 is arranged at a position substantially conjugate with the pupil of the human eye E, and has a ring-shaped transmitting portion 6a and light-shielding portions 6b and 6c as shown in FIG. The illumination light flux transmitted through the ring-shaped transmission portion 6a is incident on the human eye E as ring light P through the half mirror 7, the total reflection mirror 8, the relay lens 8'and the perforated mirror 9, and illuminates the fundus F thereof. To do.

The fundus reflected light on the fundus F passes through the hole 9a of the perforated mirror 9 and is guided to the imaging lens 22, and the barrier filter 5'is in the optical path of the photographing optical system 2 during the fluorescent fundus photographing. It is inserted and the fundus image is taken by the TV camera 23. In addition, a fluorescent agent is pre-injected into the subject for photographing the fundus of the eye.

The half mirror 7 has a function of reflecting a part of the illumination light flux passing through the ring diaphragm 2 toward the total reflection mirror 24. A detection sensor 25 as an illumination light amount detection means is provided in front of the total reflection mirror 24 in the reflection direction. The illumination light amount detection output of the detection sensor 25 is a safety amount correction circuit 26.
Has been entered. Incidentally, 27 is a support member of the detection sensor 25.

The safety amount correction circuit 26 is turned on by the control device 11.
This safety amount correction circuit 26 detects the illumination light amount above a certain limit based on the human eye lighting safety allowable accumulated light amount curve A (illumination light amount
(a0 or more) is input, an illumination light amount detection output is output to the light amount integrating circuit 28 as the light amount integrating means and the safety amount comparison control circuit 12. That is, when the illumination light quantity is a0 or less,
The safety amount correction circuit 26 prohibits the illumination light amount detection output from passing through. The light amount integrating circuit 28 is fixedly provided corresponding to the left eye and the right eye, and is turned on by the control device 11 like the safety amount correcting circuit 26. The light amount integrating circuit 28 is a memory 29
The integrated output of light intensity is output to. The content of the memory 29 is reset by the control device 11, and the light amount integrated output is stored for each input of the light amount integrated output. The output of the memory 29 is input to the safety amount comparison control circuit 12 and a bar graphic LED 30 as a warning / display means. A pair of memories 29 are provided like the light amount integrating circuit 28.

As shown in FIG. 5, the bar graphic LED 30 is color-coded so that the safety area and the dangerous area can be distinguished, and other measures have been taken.
By visually recognizing D30, it is possible to confirm the difference between the safe accumulated light amount for human eye illumination and the accumulated illumination light amount that actually illuminates the human eye, and the illumination light amount above a certain limit (illumination light amount
When illuminating with a0 or more), human eye lighting can be performed with confidence. Also, you can check how much safety margin you have, so if you want to alternate right-eye lighting and left-eye lighting,
For example, when the right eye illumination is rounded up to the left eye illumination and it is desired to perform the left eye illumination again, the bar graphic LED 30 can be used to check how much safety margin the left eye has.

The safety amount comparison control circuit 12 selects the human eye illumination safety allowable accumulated light amount based on the illumination light amount detection output of the safety amount correction circuit 26 and the human eye illumination safe allowable accumulated light amount curve A. For example, the first
As shown in the figure, if the illumination light amount is a> a0, the safety amount correction circuit 26 outputs the illumination light amount detection output a toward the safety amount comparison control circuit 12. Is a human-eye-illumination safety allowable storage amount, which is given by the product of the human-eye-illumination safety allowable storage light amount curve A and the illumination-light amount detection output corresponding to the illumination light amount a, and the allowable illumination time t ′ corresponding to the illumination light amount a. Select the light quantity at '. Then, the safety amount comparison control circuit 12 compares the human eye lighting safety allowable accumulated light amount at 'with the integrated light amount, and when the integrated light amount exceeds the selected human eye illumination safe allowable accumulated light amount at', the drive circuit.
The control signal is output toward 10. The drive circuit 10 is energized and controlled based on this control signal so as to protect the human eye. Here, the drive circuit 10 is deactivated and the illumination source 10
Is turned off.

In this embodiment, the amount of illumination light incident on the human eye E and the amount of light incident on the detection sensor 25 do not match, but a correspondence can be established in advance, so there is no problem in detecting the amount of illumination light.

FIG. 6 shows a second embodiment of the ophthalmologic apparatus according to the present invention. Instead of the total reflection mirror 8, a half mirror 7 is provided at the position where the total reflection mirror 8 was provided, and a detection sensor 25 was provided behind it. The configuration of the illumination optical system 1 is simplified.

FIG. 7 is a diagram showing a third embodiment of the ophthalmologic apparatus according to the present invention, in which the half mirror 7 shown in FIG. 2 is provided at the position of the ring diaphragm 6 and the elliptical transmission part 7a is provided in the half mirror 7. The ring diaphragm 6 is abolished. In addition, 7b and 7c are light shielding parts.
Since the half mirror 7 is arranged obliquely with respect to the optical axis, the illumination light flux that has passed through the elliptical transmission portion 7a becomes ring light P when passing through the pupil of the human eye.

Although the embodiment has been described above, the present invention is not limited to this, but includes the following.

In the embodiment, the drive circuit 10 is controlled so that the illumination light source 3 stops emitting light when the accumulated light amount exceeds the selected safe human eye lighting accumulated light amount at ', but the shutter is an illumination optical system. It may be inserted in the optical path of, and the illumination may be switched from high illumination to low illumination.

[Brief description of the drawings]

FIG. 1 is a human eye lighting safety allowable accumulated light amount curve diagram, FIGS. 2 to 5 are diagrams for explaining a first embodiment of an ophthalmologic apparatus according to the present invention, and FIG. Fig. 3, Fig. 3 is a block circuit diagram of the control device shown in Fig. 2, Fig. 4 is a plan view of the ring diaphragm shown in Fig. 2, and Fig. 5 is an enlarged view of the pergraphic LED shown in Fig. 2. 6 is an optical system diagram showing a second embodiment of the ophthalmologic apparatus according to the present invention, and FIG. 7 is a plan view of a half mirror used for explaining a third embodiment of the ophthalmologic apparatus according to the present invention. 1 ...... Illumination optical system 2 ... Shooting optical system 3 ... Illumination light source 5 '... Barrier filter 11 ... Control device 12 ... Safety amount comparison control circuit, 13 ... Camera position detection switch 14 ... Barrier filter detection Switch 15 …… Inspected eye fixed position detection switch 25 …… Detection sensor 26 …… Safety amount correction circuit 28 …… Light intensity integration circuit 30 …… Bar graphic LED E …… Human eye

Claims (7)

(57) [Claims] 1. An illumination light source for human eye illumination, an illumination optical system for guiding an illumination light flux of the illumination light source to the human eye, an illumination light amount detecting means for detecting an illumination light amount with respect to the human eye, and the illumination light amount detecting means. Illumination light amount integrating means for integrating the illumination light amount detection outputs of the illumination light amount integrating means, and comparing the light amount integrated output of the illumination light amount integrating means with the human eye lighting safety allowable accumulated light amount, and the light amount integrated output is the human eye illumination safe allowable accumulated light amount. An ophthalmologic apparatus comprising: an illumination light source control unit that controls the amount of illumination light so as to protect the human eye when it exceeds. 2. The illumination light source control means cuts off the incidence of illumination light to the human eye when the integrated light amount output exceeds the illumination safety allowable accumulated light amount. Ophthalmic device. 3. The illumination light source control means stops light emission of the illumination light source when the integrated light amount output exceeds the human eye lighting safety allowable accumulated light amount.
The ophthalmic device according to. 4. The illumination light source control means automatically switches the illumination light source from a high illuminance illumination to a low illuminance illumination when the light amount integrated output exceeds the human eye illumination safety allowable accumulated light amount. The ophthalmologic apparatus according to claim 1. 5. The illumination light source control means detects a gantry position detection switch for detecting whether the human eye is a left eye or a right eye, and determines whether the human eye is at a predetermined position. An inspected eye fixed position detection switch for detecting, and a barrier filter detection switch for detecting whether or not a barrier filter is inserted in the optical path of the photographing optical system, the gantry position detection switch, and the inspected eye The ophthalmologic apparatus according to claim 1, wherein low-illuminance illumination is switched to high-illuminance illumination when all of the fixed position detection switch and the barrier filter detection switch are turned on. 6. An illumination light source for human eye illumination, an illumination optical system for guiding an illumination light flux of the illumination light source to the human eye, an illumination light amount detecting means for detecting an illumination light amount for the human eye, and the illumination light amount detecting means. Illumination light amount integrating means for integrating the illumination light amount detection output, and determines whether or not the illumination light amount detection output is input and the illumination light amount detection output is above a certain limit based on the human eye lighting safety allowable accumulated light amount curve, A safety amount correction circuit that outputs the illumination light amount detection output toward the illumination light amount integrating means when the illumination light amount detection output of a certain limit or more is input, and the illumination light amount detection output of the safety amount correction circuit is input. Human eye lighting safety allowable accumulated light amount according to the illumination light amount detection output is selected, and the light amount integrated output is compared with the selected human eye safety safety allowed accumulated light amount to be selected by the light amount integrated output. Tolerance And it is ophthalmic apparatus and a lighting light source control means for controlling the amount of illumination light so as to improve the protection of the person eye when exceeding the product quantity. 7. An illumination light source for human eye illumination, an illumination optical system for guiding an illumination light flux of the illumination light source to a human eye, an illumination light amount detecting means for detecting an illumination light amount for the human eye, and the illumination light amount detecting means. Illumination light amount integrating means for integrating the illumination light amount detection outputs of the illumination light amount integrating means, and comparing the light amount integrated output of the illumination light amount integrating means with the human eye lighting safety allowable accumulated light amount, and the light amount integrated output exceeds the human eye illumination safety allowable light amount. An ophthalmologic apparatus comprising: a warning / display means for warning / displaying the inspector when the user touches.