JPH0299032A - ophthalmological examination equipment - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an ophthalmological examination apparatus that performs adjustments such as alignment of the eye to be examined using infrared light and then photographs an image of the eye to be examined using visible light.

(Prior art) Conventionally, ophthalmological examination devices have been used to irradiate the eye to be examined with infrared light to adjust the focus and alignment of the eye to be examined, and then irradiate the eye with visible light to take pictures. It has been known.

As this type of ophthalmological examination apparatus, a non-mydriatic fundus camera is known that takes pictures using film while keeping the eye to be examined in a natural undefeated pupil state without using a mydriatic agent.

This non-mydriatic fundus camera uses a television camera that is sensitive not only in the visible range but also in the infrared range, in order to illuminate the subject's eye with infrared light when observing the subject's eye. After making the observation image of the optometrist into a visible image on the TV monitor and making adjustments such as alignment,
It is configured to irradiate the fundus of the subject's eye with visible light and photograph a fundus image on a film.

On the other hand, in recent years, the development of image processing technology and computer technology,
With the development of large-capacity storage devices such as optical disks, attempts have been made to store and utilize images as digital or analog electronic image information rather than conventional film photography. The same applies to photographs taken in ophthalmology.In conventional eye examination equipment, which observes the subject's eye using infrared light and photographs the subject's eye using visible light, when the image is taken as an electronic image instead of film, a television camera used during observation is used. It is conceivable that this can also be used when photographing visible light.

(Problem to be solved by the invention) However, in this case, the imaging position of the fundus image is different between infrared light and visible light, so even if you observe and focus with infrared light, the visible light image cannot be captured. There is a problem in which the camera loses focus when

In addition, an index is placed on the observation optical system for alignment adjustment during observation, and since the alignment is adjusted based on this index, if the TV camera used during observation is also used when photographing the fundus, the There is a problem that sometimes this index image is photographed superimposed on the fundus image.

Therefore, there is a problem in that the television camera used during observation cannot be used when photographing the fundus using visible light.

The present invention aims to solve the problems of these conventional techniques, including the problem of out-of-focus caused by the difference in wavelength between visible light and infrared light, and the problem of index images being imprinted during photographing. By solving the above problems, it is an object of the present invention to provide an ophthalmological examination apparatus in which the television camera used during observation can also be used during photographing.

(Means for Solving the Problems) In order to achieve the above object, the ophthalmological examination apparatus according to claim 1 of the present invention provides infrared light obtained by irradiating the eye to be examined with infrared light when observing the eye to be examined. an imaging optical system that projects onto a photoelectric conversion device an image of the eye to be examined and a reference index image for adjusting the alignment of the eye image of the infrared light; and a signal from the photoelectric conversion device when observing the eye to be examined. In an ophthalmological examination apparatus having a display section that displays the infrared light image of the eye to be examined and the reference index image as visible images, When photographing the subject's eye through the imaging optical system,
a recording unit capable of recording the visible light image of the eye to be examined projected on the photoelectric conversion device as an electronic image; The present invention is characterized by comprising: a focusing position correcting means for correcting a deviation of each focal point position from an image of the eye to be examined; and an index image canceling means for invalidating the reference index image when photographing the eye to be examined. .

The ophthalmological examination apparatus according to claim 2 of the present invention further includes an imaging optical system that projects an image of the eye to be examined onto a photoelectric conversion device, and an imaging optical system that projects an image of the eye to be examined on the photoelectric conversion device during observation of the eye to be examined. In the ophthalmological examination apparatus, the ophthalmological examination apparatus has a display section that displays an image of the eye to be examined using infrared light as a visible image based on a signal of f! l
Conversion i! a recording unit capable of recording an image of the eye to be examined in visible light as an electronic image in accordance with a signal from the camera; a focusing position correcting means for correcting the deviation of each focal point position from the image; It is characterized by comprising a pattern signal recording section that generates an electric signal corresponding to the reference index image.

(Function) According to the ophthalmological examination apparatus according to claim 1 of the present invention, an infrared image of the eye to be examined obtained by irradiating the eye to be examined during observation of the eye to be examined is obtained by using the imaging optical system. It is projected onto a photoelectric conversion device via the photoelectric conversion device. At this time, an infrared light image of the subject's eye and a reference index image for alignment are projected onto the photoelectric conversion device. These images projected onto the photoelectric conversion device are displayed as visible images by the display section. Thereby, alignment adjustment of the eye to be examined can be performed. When adjusting the alignment of the eye to be examined, the reference target image is canceled by the target image canceling means, and visible light is irradiated to photograph an image of the eye to be examined using visible light. When photographing the subject's eye, the visible light image of the subject's eye is projected onto the photoelectric conversion device via the imaging optical system. The deviation in the focal position of the light is corrected, and an image of the eye to be examined using visible light is formed on the photoelectric conversion device. Since the reference index image for alignment has been eliminated, only the visible light image of the subject's eye is projected onto the photoelectric conversion device, and this visible light subject's eye image is displayed on the display section + knee.
L. Further, the visible light image of the eye to be examined projected onto the photoelectric conversion device is stored in the storage unit and used as image information of the eye to be examined.

Further, according to the ophthalmological examination apparatus of claim 2, a reference index image for alignment adjustment is recorded in the pattern signal recording section, and this reference index image is used when displaying an electronic image of the eye image to be examined on the display section. In addition, since it is displayed superimposed on the electronic image of the eye to be examined, alignment adjustment of the eye to be examined can be performed.

(Example) Hereinafter, a fundus camera according to an example of the ophthalmological examination apparatus of the present invention will be described with reference to the drawings.

FIG. 1 shows the configuration of a fundus camera 1 according to this embodiment. an optical system 20 , a television camera 30 (photoelectric conversion device) that receives the image from the imaging optical system 10 , a controller 40 (storage unit) capable of storing the image received by the television camera 30 , and a controller 40 (storage unit) that can store the image received by the television camera 30 . A television monitor (display unit) that displays the image as a visible image, a film camera 60 that takes an image of the eye to be examined, a glass plate 70 that serves as a focusing position correction means, and an index that eliminates the alignment index during observation. A reticle/glass plate drive unit 80 as an image resolution means, and a working distance index projection system 9 that irradiates a working distance riim index for adjusting the working distance of the fundus camera 1 with respect to the eye 2 to be examined.
0.

The imaging optical system 10 includes an objective lens system 11 facing the eye to be examined;
A perforated mirror 12 that reflects the illumination light from the illumination optical system 20 to the eye 2 through the objective lens system 11, and a small mirror that irradiates the eye 2 with the working distance #1 adjustment index from the working distance index projection system 90. It has a mirror 13, a focusing lens system 14, an imaging lens system 15, a quick return mirror 16, a reticle 17, a reflecting mirror 18, and a relay lens 19. The small mirror 13 is located outside the optical path 9 of the imaging optical system 10, and the working pressure 111 adjustment index projected from the working distance index projection system 90 is directed to the subject's eye 2 via the perforated mirror 12 and the objective lens system 11. It is set so that it is projected onto a point α at 1/2 of the center of curvature of the cornea and is reflected as a parallel beam of light on the cornea. Further, the quick return mirror 16 is provided with a quick return mirror drive section 16a that is driven under the control of the controller 40, and even when photographing with the television camera 30 during observation, the imaging lens system 1
It is located in the raised position so as to guide the image from 5 to the television camera 30. When photographing with the film camera 60, the quick return mirror 16 is located at the lowered position and forms an image from the imaging lens system 15 on the film 61 of the film camera 60. On reticle 17,
In this embodiment, the quick return mirror 16 has an alignment index for adjusting the alignment of the subject's eye 2, and is provided so that the image reflected by the quick return mirror 16 is once formed on the reticle 17. A glass plate 70, which will be described later, is provided integrally with the reticle 17, and the glass plate 70 and the reticle 17 are slidably moved by an index image eliminating means 80.

The illumination optical system 20 includes an illumination light source 21 for observation, a strobe tube 22 as an illumination light source for photography, an observation condenser lens system 23 for condensing light from the illumination light source 21, and light from the strobe tube 22. a hot mirror 25 that reflects only the infrared component of the light from the observation condenser lens system 23 and transmits the visible component of the light from the observation condenser lens system 24; A ring diaphragm 26 that forms the light from the hot mirror 25 into a ring shape, and an illumination relay lens system 2 that guides the ring light from the ring diaphragm 26 to the perforated mirror 12 of the imaging optical system 10.
7.

The observation illumination light source 21 is controlled to emit light by the controller 40, and emits light in response to a command from the controller 40 when the fundus camera 1 is in the observation state. The photographing strobe tube 22 is connected to the controller 40 via a strobe drive section 22a. The strobe tube 22 is
The light emission is controlled by the controller 40, and the light is emitted when the fundus camera 1 takes an image.

A controller 40 is connected to the television camera 30 as a photoelectric conversion device, and an image received by the television camera 30 is stored in a frame memory 41 (see FIG. 2) of the controller 4o.

The controller 40 includes the above-mentioned frame memory 41, an interface 42, and a CP as a central processing unit.
The CPU 43 has a reticle/glass drive section 80, a quick return mirror drive section lea, a strobe drive section 22a, a television camera 30, and a flash tube 22 for causing the strobe tube 22 to emit light. trigger switch 22b and the television camera 3
a mode setting unit 44 for setting either a television camera shooting mode for shooting with 0 or a photo shooting mode for shooting with a film camera 60; and a mass storage 45 as an external storage device such as a disk device.
are connected.

This controller 40 controls the fundus camera 1 as follows.

First, when the main switch (not shown) of the fundus camera 1 is turned on, the CPU 43, television camera 30, and television monitor 50 start up, the observation illumination light source 21 turns on, and the working distance adjustment device 90 becomes operational. , the fundus camera 1 enters an observation state for observing the eye 2 to be examined.

In the observation state, a signal from the CPU 43 causes the reticle/glass plate drive section 80 to move the reticle 17 into the coupling optical system 1.
0, and the quick return mirror drive section 16a is controlled to position the quick return mirror 16 at the raised position.

In this state, the image of the subject's eye projected on the television camera 30 is transferred to the television monitor 5 via the frame memory 41.
Displayed as 0. The working distance adjustment device 9 is operated by an observer who observes the eye image displayed on the television monitor 50.
The working distance of the fundus camera 1 is adjusted based on the working distance adjustment index from 0, and the fundus image of the eye to be examined 2 is located at the center position of the alignment index of the reticle 17, and the television camera 3
When alignment adjustment and focusing are performed so that 0 is displayed, the fundus camera 1 becomes ready for photographing.

Next, set the television camera shooting mode with the mode setting switch 44, and set the trigger switch 22b, which is the shooting switch.
When the trigger switch 22b is turned on, the on signal of the trigger switch 22b is input to the CPU 43 via the interface 42, and at the same time, the reticle/glass plate drive section 80 is driven via the interface 42 in response to a command from the CPU 43, and the reticle 17 is moved. After the glass plate 7o is positioned at the original position, the strobe drive unit 22a is driven to cause the strobe tube 22 to emit light. The strobe tube 22 emits light from the television camera 3 based on a signal from the video synchronization separation section 41a.
It is performed in accordance with the image reception timing of 0. strobe tube 2
The fundus image of the eye to be examined 2 obtained by the light emission of 2 is formed on the light-receiving surface of the television camera 30 via the glass plate 70, photoelectrically converted by the television camera 30, and then stored in the frame memory 41.
will be newly memorized.

The frame memory 41 is capable of storing an image received by the television camera 30, and when the image of the eye to be examined is received a plurality of times, the image of the eye to be examined is selected from among the images of the eye to be examined by the controller 40. It is also possible to display a desired image on the television monitor 50 based on instructions. This frame memory 41 can directly transmit an image signal to the television monitor 50 during observation, and when the image signal is input from the frame memory 41 to the television monitor 50, the alignment index image and the eye image to be examined are displayed on the television monitor 50. is displayed as a visible image.

In addition, when in the TV camera shooting mode, the fundus image charged and changed by the TV camera 30 is stored in the frame memory 41, and is processed by the CPU 43 via the interface 42 as necessary, or the original image or the The results are stored in mass storage 45, which is an external storage device. The mass storage 45 is composed of, for example, an information recording device such as a magnetic disk device or an optical disk device.

The fundus image and data related to the fundus image stored in the mass storage 45 can be reproduced again on the television monitor 50 via the interface 42, CPU 43, and frame memory 41.

When the photographing of the subject's eye is completed, the reticle/glass plate drive section 80 and the quick return mirror drive section 16a are operated in response to a command from the CPU 43, and the optical path 9 of the imaging optical system 10 is activated.
The reticle 17 is inserted above, and the quick return mirror 16 is raised to return to the observation state.

When the mode setting unit 44 sets the photography mode and turns on the trigger switch 22b, which is the photography switch,
The ON signal of the trigger switch 22b is input to the CPU 43, and the quick return mirror drive unit 18a is activated to lower the quick return mirror 16, and the strobe tube 22
emits light. The fundus image obtained by the light emission of the strobe tube 22 is guided to the imaging optical system 10 and formed on the film 61 of the film camera 60 via the imaging lens system 15.

The shutter of this film type camera 60 is opened and closed based on a signal from the CPU 43. The film 61 is normally a 35 mm film, but can be replaced with a Polaroid film (trademark) or the like as needed. When a Polaroid film is used, the image size is changed using a relay lens or the like.

3 and 4 show a glass plate 70 as a focusing position correcting means for correcting the deviation between the focusing position of infrared light and the focusing position of visible light passing through the optical path 9 of the imaging optical system 10. In the six embodiments showing the effect, the correction of the in-focus position and the cancellation of the alignment index image are performed simultaneously by mechanical movement.

That is, the glass plate 70 is formed of a parallel plane plate, and the ends of the glass plate 70 and the ends of the reticle 17 are connected.

By moving the glass plate 70 and the reticle 17 back and forth in a direction across the optical path 9, the shift in the focus position is corrected and the alignment index image is invalidated at the same time.
By driving the reticle/glass plate drive 80 described above, the glass plate 70 and the reticle 17 are moved back and forth.

FIG. 3 shows the deviation between the focal position A1 of the infrared light IR and the focal position A2 of the visible light R when the glass plate 70 is not present. As shown in the eye image of the transmitted visible light V, the glass plate 70
is inserted into the optical path 9, the focal position A2 of the visible light V coincides with the focal position At of the infrared light IR, and the focal position A1, A2
The deviation between the two is corrected. As a result, a visible light V image of the eye to be examined is formed on the light receiving surface of the television camera 30 in the same way as an infrared IR image of the eye to be examined.

FIG. 5 shows a modification in which the glass plate 70 and the reticle 17 are integrally constructed. In this example, the glass plate 70 and the reticle 17 are integrally provided in an "L" shape. There is. A rotation shaft 70' is provided at the joint portion of the glass plate 70 and the reticle 17, and the reticle/glass plate drive unit 80 rotates the glass plate 70 and the reticle 17 together to adjust the focus position. The alignment target image is corrected and the alignment index image is invalidated.

In addition to the above method, a method for correcting the deviation between the focal position of the eye image of the subject's eye using infrared light IR and the focal position of the eye image of the subject's eye using visible light V is to insert a lens in place of the glass plate 70. how to,
A method of moving any lens after the perforated mirror 12 or the light receiving surface of the television camera 30 using a piezo probe or a solenoid, or a method of moving any lens from the perforated mirror 12 to the television camera 30 with a liquid crystal lens. This may be done by adjusting the focus as follows.

FIG. 6 shows a case where a pattern 17a for forming an alignment index using liquid crystal is formed on the reticle 17 as the index image eliminating means. In this case, during observation, the reticle pattern 17a is formed by a command signal from the controller 40,
In TV camera shooting mode, this reticle pattern 1
Eliminate 7a. In this way, the alignment index can be eliminated by electrical operation of the controller 40 based on the designation of the photographing mode, and the configuration of the fundus camera 1 can be simplified.

In addition, as the index image resolution means, as shown in FIG.
The reticle pattern may be formed of an infrared reflecting mirror that reflects infrared light for alignment adjustment but transmits wavelength light for inputting an image. In this way, the infrared light image of the subject's eye is reflected by the infrared light reflecting mirror of the desired shape, and the visible light passes through the infrared light reflecting mirror, making it easier to observe.
A desired reticle pattern can be formed when the reticle is scanned, and there is no need to operate the reticle 17 using a signal from the controller 40 just to eliminate the alignment index.

FIG. 8 shows a configuration example of another embodiment that is used as an alignment index. In this embodiment, the reticle includes a signal superimposition circuit 100 connected to a frame memory 41;
Synchronous separation clock generation circuit 110, pattern ROM 120
It is formed by

In this embodiment, the signal superimposition circuit 100 is provided between the frame memory 41 and the television monitor 50 to prevent the quality of the input image from the frame memory 41 from deteriorating. The output of the frame memory 41 is input to the synchronous separation clock generation circuit 110 and the signal superposition circuit 100. Synchronous separated clock generation circuit 110 generates a clock used to read the contents of pattern ROM 120 from the synchronous component of the input signal.

The signal input to the signal superposition circuit 100 is clamped by the level clamp circuit 130 so that the black level of the television signal or a level equivalent to this is always constant, and then input to the analog switch 140. Since the analog switch 140 is normally connected to output the output of the level clamp circuit 130 to the television monitor 50, the output image of the frame memory 41 is output to the television monitor 50, but due to the output from the pattern ROM 120, , a white level voltage or a black level voltage corresponding to the white and black of the television signal, respectively, is output to the television monitor 50. Since data corresponding to a desired reticle pattern is set in the pattern ROM 120, the desired reticle pattern is displayed on the television monitor 50 superimposed on the output image from the frame memory 41 during observation.

Note that in the photographing mode, a disable signal from the controller 40 is input to the signal superimposition circuit 100, but while this disable signal is input, the analog switch 140 switches between the frame memory 41 and the television monitor 50. is always connected, and when photographing with a television camera, the output image of the frame memory 41 is displayed on the television monitor 50 without a reticle pattern. This eliminates the need to provide the reticle 17 on the optical path 9.

(Effects of the Invention) Since the ophthalmological examination apparatus according to the present invention is configured as described above, there are problems of out-of-focus caused by the difference in wavelength between visible light and infrared light, and problems of index images being imprinted during photographing. Since the television camera used during observation of the ophthalmological examination apparatus can also be used for photographing, it is possible to improve the photographing function of the ophthalmological examination apparatus.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a fundus camera according to an embodiment of the present invention;
Fig. 2 is a block diagram showing the configuration of the controller of the fundus camera shown in Fig. 1, and Fig. 3 shows the focusing position of infrared light and the focusing position of visible light in the optical path of the imaging optical system of the first embodiment. An explanatory diagram showing the deviation from the position, Fig. 4 is an explanatory diagram showing the state in which the focused position of visible light is corrected when a glass plate is inserted into the optical path of Fig. 3, and Fig. 5 is an explanatory diagram showing the state in which the focal position of visible light is corrected when a glass plate is inserted into the optical path of Fig. 3. FIG. 6 is a diagram showing another configuration of the focusing position correction means and target image eliminating means in the example, FIG. 6 is a diagram showing another configuration of the target image eliminating means in the first embodiment of the present invention, and FIG. 7 is a diagram showing another configuration of the target image eliminating means in the first embodiment of the present invention. FIG. 8 is a diagram showing the reflection characteristics of the infrared light reflecting mirror of the target image eliminating means, and FIG. 8 is a configuration diagram of a second embodiment of the present invention. ... Fundus camera... Examination ■Application 0... Imaging optical system 0... Illumination optical system 0... Television camera (photoelectric conversion device) 0... Controller (storage unit) 0... TV monitor (display section) 0...Film type camera 0...Glass plate (focusing position correction means) 0...Target image eliminating means 20...Pattern ROM (pattern signal recording section) Condolence map Funeral map

Claims (2)

[Claims] (1) During observation of the eye to be examined, photoelectric conversion is performed between the infrared eye image obtained by irradiating the eye to be examined and a reference index image for adjusting the alignment of this infrared eye image. An ophthalmology clinic comprising: an imaging optical system for projecting images onto an apparatus; and a display section that displays the infrared light image of the eye to be examined and the reference index image as visible images based on a signal from the photoelectric conversion device when observing the eye to be examined. In the inspection apparatus, when photographing the eye to be examined, a visible light image of the eye to be examined obtained by irradiating the eye to be examined is taken via the imaging optical system;
a recording unit capable of recording the visible light image of the eye to be examined projected on the photoelectric conversion device as an electronic image; An ophthalmology clinic comprising: a focus position correcting means for correcting a deviation of each focal position from an image of the eye to be examined; and an index image canceling means for invalidating the reference index image when photographing the eye to be examined. Inspection equipment. (2) An imaging optical system that projects an image of the eye to be examined onto a photoelectric conversion device; and an imaging optical system that irradiates the eye to be examined with infrared light; when observing the eye to be examined, an image of the eye to be examined using infrared light can be generated using a signal from the photoelectric conversion device; In an ophthalmological examination apparatus having a display unit that displays a visual image, a recording unit that can record a visible light image of the eye to be examined as an electronic image based on a signal from the photoelectric conversion device when photographing the eye to be examined by irradiating the eye to be examined with visible light. and a focusing position correction means, which is provided in the imaging optical system and corrects a shift in focal position between an infrared light image of the eye to be examined and a visible light image of the eye to be examined when photographing the eye to be examined, and the eye to be examined. The method further comprises a pattern signal recording section that generates an electric signal corresponding to the reference index image in order to display a reference index image for alignment adjustment on the display section superimposed on the eye image to be examined only during observation. An ophthalmological examination device.