JP2010042068A - Ophthalmic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ophthalmic apparatus carrying out ophthalmic inspection such as gonioscopy and funduscopy by irradiating an eye to be inspected with slit light in a simple construction. <P>SOLUTION: The anterior segment 1b of the eye to be inspected is irradiated with infrared slit light 73 whose longitudinal direction is directed in a substantially horizontal direction to the eye 1 to be inspected from below the eye to be inspected in a predetermined elevation angle θ. The moving images of a cornea reflection slit image and an iris reflection slit image of the anterior segment along with the image of the anterior segment by the slit light are imaged by an imaging device 40. The still images of the anterior segment along with the respective slit images are imaged and stored in an image memory 62b as the still images when switched to the fundus imaging via a switching device 63. The cornea reflection slit image and the iris reflection slit image are extracted from the images stored in the image memory and the gonio angle is obtained. In such the constitution, the gonioscopy can be carried out during a series of actions of the funduscopy usually done. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ophthalmologic apparatus, and more particularly to an ophthalmologic apparatus having an ophthalmologic examination function such as a fundus examination and a corner angle examination.

  Conventionally, diagnosis of glaucoma is performed by examining the fundus using an ophthalmologic apparatus, or diagnosis of primary angle-closure glaucoma by examining the angle (corner angle) between the cornea of the eye to be examined and the region of the iris. Has been implemented. Primary angle-closure glaucoma is a disease that results in increased intraocular pressure as a result of obstruction of the aqueous humor outflow from the anterior chamber corner by blocking the corner at the periphery of the iris.

  For the corner inspection, for example, there is an ophthalmic examination apparatus described in Patent Document 1. This apparatus calculates the corner angle by scanning the visible slit light from the left or right oblique direction with the projection angle fixed with respect to the visual axis of the subject eye toward the anterior eye portion of the subject eye.

Further, Patent Document 2 discloses an anterior ocular segment photographing apparatus for observing an anterior eye with infrared light and irradiating visible slit light to measure a corner angle. Patent Document 3 discloses a hand-held fundus camera that can be observed by irradiating a slit of infrared light and can photograph the fundus with a non-mydriatic eye without forcibly opening the pupil with a mydriatic agent or the like. Patent Document 4 discloses a slit projector that emits horizontal slit light from the lower part of the eye to be examined.
Japanese Patent No. 3878164 JP-A-1-285241 JP 2003-47595 A JP-A-62-34529

  When performing a corner angle examination, slit light is irradiated to the anterior eye portion of the eye to be examined. However, in the method described in Patent Document 1, slit light is distributed to the left and right of the eye to be examined and irradiated to the eye to be examined. There is a problem that the light irradiation mechanism becomes complicated.

  In addition, early detection of primary angle-closure glaucoma is important, and it is desirable to be able to perform angle examination when diagnosing glaucoma by fundus examination. However, in Patent Documents 1 to 4 described above, one of the fundus examination and the corner examination can be performed, but both examinations cannot be performed. For this reason, there is a problem that the corner angle inspection cannot be performed during a series of operations for fundus photographing which is one of the fundus inspections.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide an ophthalmologic apparatus capable of performing ophthalmic examination by irradiating a subject eye with slit light with a simple configuration.

In order to solve the above problems, an ophthalmologic apparatus according to the present invention provides:
A slit light illumination mechanism for irradiating the anterior ocular segment of the subject eye with a predetermined elevation angle from below the subject eye with infrared slit light whose longitudinal direction is substantially horizontal to the subject eye;
And an imaging mechanism for imaging the anterior segment of the subject's eye irradiated with the slit light as a still image.

The ophthalmic apparatus according to the present invention is
An ophthalmologic apparatus capable of switching between anterior ocular segment imaging and fundus imaging,
A slit light illumination mechanism for irradiating the anterior ocular segment of the subject eye with a predetermined elevation angle from below the subject eye with infrared slit light whose longitudinal direction is substantially horizontal to the subject eye;
First imaging means for imaging the anterior segment of the eye to be examined;
Second imaging means for imaging the fundus of the eye to be examined,
The first imaging means has a moving image imaging function and a still image imaging function,
When the anterior ocular segment is switched from anterior ocular segment imaging to fundus imaging while moving images are captured along with the anterior ocular slit image by the slit light illumination mechanism, the anterior ocular segment is imaged together with the anterior ocular slit image. It is characterized by being.

  According to the present invention, since the infrared slit light whose longitudinal direction is substantially horizontal with respect to the eye to be examined is applied to the anterior eye part to be examined at a predetermined elevation angle from below the eye to be examined, Even a patient with poor opening can irradiate the eye with slit light with a simple configuration, and the corner examination can be performed efficiently.

  Further, according to the present invention, the anterior segment is imaged together with the anterior segment slit image, and when the anterior segment imaging is switched to the fundus imaging, the anterior segment is captured together with the anterior segment slit image. Therefore, the corner examination can be performed during a series of operations of the fundus examination that is normally performed, and an efficient ophthalmic examination can be performed.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is an optical diagram showing a configuration of an ophthalmologic apparatus according to an embodiment of the present invention. The ophthalmologic apparatus 10 shown in FIG. 1 is provided with an illumination optical system that illuminates the fundus 1a of the eye 1 to be examined and an imaging optical system that captures the illuminated fundus.

  In the illumination optical system, light emitted from an infrared light source 11 composed of a plurality of infrared LEDs passes through the strobe 14 and is incident on the diffusion plate 15 and diffused, and is conjugate with the anterior eye portion 1 b of the eye 1 to be examined. The ring slit 16 disposed at the position is illuminated. The illumination light from the ring slit 16 passes through the lens 17, the black dot plate 18 for removing the reflection of the objective lens 22, the half mirror 19, and the relay lens 20, and a perforated total reflection mirror 21 having a hole in the center. Then, the light passes through the objective lens 22 and is incident on the fundus 1a from the anterior eye portion 1b of the eye 1 to be illuminated. The fundus 1a is illuminated with infrared light.

  Reflected light from the fundus 1a is received through the objective lens 22, passes through the hole of the perforated total reflection mirror 21, passes through the photographing aperture 31, the focus lens 32, and the imaging lens 33, and is reflected by the half mirror 34. The reflected light is incident on the infrared transmission visible reflection mirror 36 through the field stop 35 disposed at a position conjugate with the fundus 1a. The infrared light transmitted through the infrared transmission visible reflection mirror 36 is reflected by the mirror 38, passes through the imaging lens 37, and is in a position conjugate with the fundus composed of an infrared CCD having sensitivity to the infrared light. The light enters a certain imaging device (first imaging means) 40.

  The image picked up by the image pickup device 40 is guided to the switch 63, and when the switch 63a of the switch 63 is in the illustrated position, it is guided to the monitor 41 and displayed there. When the switch 63a is switched to the position indicated by the dotted line, an image photographed by the imaging device 40 is input to an image memory (recording unit) 62b of the image processing unit 62 described later.

  In addition, the visible light reflected by the mirror 36 is imaged at a position conjugate with the fundus occupying a visible CCD or the like having sensitivity to visible light via at least two kinds of variable magnification lenses 47a and 47b. Light is received by the device (second imaging means) 53.

  The imaging device 40 has a moving image capturing function for capturing a moving image, and, as will be described later, for example, one frame is set as a still image by a still image capturing signal from the control unit 60, and the image is processed by the image processing unit 62. It also has a still image capturing function to be recorded in the memory 62b.

  The ophthalmologic apparatus 10 is further provided with a slit light illumination mechanism for irradiating the anterior eye portion 1b of the eye 1 to be examined with infrared slit light. The slit light illumination mechanism includes an infrared light source 71 such as an infrared LED, a lens 72, a slit forming mechanism 73 including disks 74 and 75 that can rotate around a shaft 76, and lenses 77 and 78.

  As shown in FIG. 2, a plurality of circular holes 74 a to 74 d having different diameters are formed in the disk 74 of the slit forming mechanism 73, and the centers of the circular holes are equidistant from the shaft 76. By rotating around 76, one of the circular holes can be moved to a position that matches the optical axis 2 of the slit light illumination mechanism. The disk 75 of the slit forming mechanism 73 is formed with a plurality of slits 75a to 75c having different slit widths and the same length in the longitudinal direction, and a through hole 75d. Can be moved to a position where the center thereof coincides with the optical axis 2 of the slit light illumination mechanism. When the center of each slit 75a to 75c moves to a position coincident with the optical axis 2, the longitudinal direction thereof is perpendicular to the optical axis 2 and is horizontal or substantially horizontal with respect to the eye to be examined. It is formed.

  For example, as shown in FIG. 2, when the center of the slit 75a is moved to the position of the optical axis 2 by rotating the disk 75, a slit having a predetermined width is formed, and then the disk 74 is rotated to rotate the slit 74a. Therefore, a slit having a predetermined width and a predetermined length can be formed by rotating the disks 74 and 75.

  The slit forming mechanism 73 is disposed below the eye 1 so that the optical axis 2 is at a predetermined angle θ, for example, 45 degrees, with the optical axis 3 of the illumination optical system. Thereby, the infrared slit light whose longitudinal direction is substantially horizontal to the eye 1 to be examined can be applied to the anterior eye portion to be examined at a predetermined elevation angle θ from below the eye to be examined.

  Further, the illumination optical system is provided with a focus dot light source 30, and a light beam from the light source 30 is incident on the fundus 1 a via the half mirror 19, and the focus dot position changes according to the movement of the focus lens 32. The examiner can focus on the eye to be examined by observing the focus dot.

  In the initial stage of alignment for aligning the line of sight of the eye to be examined with the optical axis, the anterior eye lens 42 is inserted into the imaging optical path, and an infrared light source 80 composed of infrared LEDs is turned on in synchronization with the anterior eye lens. 1b is illuminated with infrared light. The image of the anterior segment 1b is captured by the imaging device 40, and the examiner can observe the image of the anterior segment 1b on the monitor 41.

  Further, during the alignment or focusing operation, the internal fixation lamp 43 is turned on, and the examiner ensures the alignment or focusing operation by causing the subject to gaze at the fixation lamp.

  The image processing unit 62 includes a CPU 62a, an image memory 62b, a RAM 62c, a ROM 62d, and the like. The CPU 62a processes the image stored in the image memory 62b and calculates various data. The RAM 62c is used as a working memory for image processing and calculation, and the ROM 62d is used for storing image processing programs, fixed data, and the like. Images and various data recorded in the image memory 62 b can be displayed on the monitor 64.

  A control unit 60 including a CPU controls lighting of the infrared light sources 11 and 71, the focus dot light source 30, and the fixation lamp 43 according to a signal from an operation key on the operation panel 61, and a shutter switch 46. Is operated, a still image capturing signal is sent to the imaging device 53 and the image processing unit 62, and the strobe 14 is caused to emit light. When the switching key 61a for switching between anterior ocular segment imaging and fundus imaging provided on the operation panel 61 is operated, the control unit 60 sets the switch 63a of the switching unit 63 to a position indicated by a dotted line in FIG. Switching is performed, and a still image capture signal is sent to the imaging device 40 and the image processing unit 62. In addition, the control unit 60 performs insertion / removal of the anterior eye lens 42 and the variable magnification lenses 47a, 47b to / from the optical path, rotation control of the disks 74, 75 of the slit forming mechanism 73, and various data with the image processing unit 62. Exchange. In FIG. 1, reference numerals in parentheses of arrows output from the control unit 60 indicate that the above-described signals are transmitted from the control unit 60 to members or elements indicated by the reference numerals.

  The switch key 61a, the switch 63, and the like of the operation panel 61 constitute a switching unit that switches between anterior ocular segment imaging and fundus imaging.

  In FIG. 1, symbol R indicates a position conjugate with the fundus 1a of the eye 1 to be examined, and P indicates a position conjugate with the anterior eye portion (particularly the pupil) 1b.

  In the ophthalmologic apparatus configured as described above, the flow of operations for performing fundus examination and corner examination will be described below.

  The infrared light source 11 is turned on and the eye fundus 1a to be examined is illuminated with infrared light. In the initial stage, alignment is performed based on the image of the anterior segment. Therefore, the anterior segment lens 42 is inserted into the optical path, and the infrared light source 80 is turned on in synchronization with it, and the anterior segment 1b is illuminated with infrared light. Is done. The anterior segment 1b illuminated with infrared light is imaged by the imaging device 40, and the image of the anterior segment 1b is displayed on the monitor 41 via the switch 63. The image of the part 1b can be observed on the monitor 41, alignment can be performed, and the anterior eye part 1b can be focused.

  When the alignment and focusing operations are completed, the infrared light source 71 is turned on, and the slits 74 and 75 of the slit forming mechanism 73 are rotated to form a slit having a predetermined width and a predetermined length. The infrared slit light that has passed through the slit has a longitudinal direction that is substantially horizontal with respect to the eye 1 to be examined, and is applied to the anterior eye portion of the eye at a predetermined elevation angle θ from below the eye to be examined. This state is illustrated in FIG.

  The infrared slit light applied to the anterior eye portion 1b to be examined proceeds along the optical axis 2 and forms a slit image with the cornea 101 of the anterior eye portion 1b as shown in FIG. An image is formed, and these slit images are photographed as moving images by the imaging device 40 as a corneal reflection slit image 103 and an iris reflection slit image 104 and displayed on the monitor 41. FIG. 4 shows an image 1 b ′ of the anterior eye portion 1 b of the eye to be examined and a corneal reflection slit image 103 and an iris reflection slit image 104 on the monitor 41.

  As described above, when the switching key 61a of the operation panel 61 is operated while the anterior eye portion 1b is moving imaged together with the slit images 103 and 104, the control unit 60 switches the switch 63a of the switch 63 to the state shown in FIG. The position is switched to the position indicated by the dotted line for a predetermined time, and a still image capture signal is sent to the imaging device 40 and the image processing unit 62. As a result, the image 1b ′ of the anterior eye portion 1b to be inspected imaged by the imaging device 40 is taken into the image processing unit 62 as a still image together with the corneal reflection slit image 103 and the iris reflection slit image 104, and the image is stored in the image memory 62. To be recorded.

  The control unit 60 returns the switch 63a of the switch 63 to the position shown in FIG. 1 after a predetermined time necessary for recording the still image, and in synchronism with this, causes the anterior eye lens 42 to leave the optical path, The infrared light source 80 is turned off. As a result, the fundus illuminated by the infrared light source 11 is imaged as a moving image by the imaging device 40, so that a moving image of the fundus 1 a to be examined is displayed on the monitor 41.

  Since the fundus image is displayed on the monitor 41 by the examiner, the image can be observed and aligned, and the focus dot light source 30 can be turned on to focus on the fundus of the eye to be examined. At this time, the alignment or focusing operation can be ensured by having the subject gaze at the fixation lamp 43.

  When the alignment and focusing operations are completed, the shutter switch 46 is operated, and a still image capture signal output from the control unit 60 in response to this operation is input to the imaging device 53 and the image processing unit 62. Then, the image pickup device 53 is activated to start taking in a still image of the fundus 1a, and a signal that instructs the strobe 14 to emit light from the image pickup device 53 in synchronization with the still image take-in signal is controlled by the CPU 62a of the image processing unit 62. Since it is transmitted via the unit 60, the strobe 14 emits light. The fundus image illuminated by the light emission of the strobe 14 is captured as a still image by the imaging device 53.

  The fundus still image captured by the imaging device 53 is recorded in the image memory 62 b of the image processing unit 62. Since the image of the anterior eye 1b to be examined is stored together with the slit image in the image memory 62b, the fundus image is recorded in a memory area different from the area in which the image of the anterior eye part is stored.

  The image stored in the image memory 62b can be displayed on the monitor 64, stored in an external storage device (not shown), or output to a printer (not shown).

  In the ophthalmologic apparatus of the present invention, as described above, the corneal reflection slit image and the iris reflection slit image formed by projecting the slit light onto the anterior eye portion to be examined are captured as a still image together with the image of the anterior eye portion to be examined. Therefore, the angle formed by each slit image, that is, the corner angle can be obtained. Hereinafter, a method for obtaining this corner will be described.

  When the corneal reflection slit image 103 and the iris reflection slit image 104 stored in the image memory 62b are read and displayed on the monitor 64 together with the anterior eye image, an image as shown in FIG. 4 is displayed. In the figure, the corneal reflection slit image 103 and the iris reflection slit image 104 are designated as straight lines 103a and 104a. The straight lines 103a and 104a are taken into the CPU 62a of the image processing unit 62, and an angle α formed by each straight line is calculated and set as a corner angle.

  In the method shown in FIG. 5, the corneal reflection slit image 103 and the iris reflection slit image 104 are extracted from the image stored in the image memory 62b to obtain the corner angle. The corneal reflection slit image 103 and the iris reflection slit image 104 have a high luminance and a constant value, and are different in luminance from the surrounding anterior ocular segment images. Therefore, the image stored in the image memory 62b is read out for each pixel. The luminance value of each pixel is compared with a predetermined threshold value. Then, a pixel exceeding the threshold is extracted to cut out a slit image. At this time, the pixel P1 (x2, y2) extracted at the intersection of the corneal reflection slit image 103 and the iris reflection slit image 104 is a pixel separated by a predetermined number of pixels to the left of the pixel P1, and the iris reflection slit image 104 The pixel P2 (x1, y2) extracted as being and the pixel P3 (x1, y1) extracted as being the corneal reflection slit image 103 among the pixels below the pixel P2 are selected, and the pixels P1 and P2 are connected. An angle α formed by the line 104b and the line 103b connecting the pixels P1 and P3 is calculated and set as a corner angle.

  In the above-described method, there is a possibility that the anterior segment image may be erroneously recognized as a slit image. Therefore, when the anterior segment image is captured by the imaging device 40, when two images are continuously captured and the first image is captured, As described above, the anterior segment image is captured together with the slit images 103 and 104, and is stored in the image memory 62b. Subsequently, the infrared light source 71 is turned off and only the anterior segment image is captured and stored in another area of the image memory 62b. By subtracting the twelfth and second images, the slit images 103 and 104 as shown in FIG. 5 can be extracted with high reliability, and a highly accurate corner angle can be calculated.

  As described above, according to the present invention, corner examination (measurement) can be performed in the course of a series of operations of a fundus examination that is normally performed. In other words, during a series of operations of non-mydriatic fundus photography. Since corner examination (or corner observation and measurement) can be performed, the examination efficiency of the eye to be examined can be improved.

  In the present invention, since the infrared slit light whose longitudinal direction is substantially horizontal with respect to the subject's eye is irradiated from the lower part of the subject's eye to the anterior eye portion to be examined at a predetermined elevation angle, Even a patient with poor opening can irradiate the eye with slit light with a simple configuration, and the corner examination can be performed efficiently.

It is an optical diagram which shows the structure of the ophthalmologic apparatus which concerns on embodiment of this invention. It is the block diagram which showed functionally the structure of the slit formation mechanism of said ophthalmologic apparatus. It is sectional drawing of the eye to be examined which showed the state which projects slit light on the anterior eye part. It is explanatory drawing which shows the image of the anterior eye part obtained by irradiating slit light to an anterior eye part. It is explanatory drawing which showed the method of calculating | requiring a corner angle from a cornea reflection slit image and an iris reflection slit image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Eye to be examined 1a Fundus 1b Anterior eye part 11, 71, 80 Infrared light source 14 Strobe 21 Perforated total reflection mirror 22 Objective lens 31 Imaging diaphragm 32 Focus lens 33 Imaging lens 40, 53 Imaging device 42 Anterior eye lens 46 Shutter switch 60 Control unit 61 Operation panel 62 Image processing unit 63 Switch 103 Cornea reflection slit image 104 Iris reflection slit image

Claims (7)

A slit light illumination mechanism for irradiating the anterior ocular segment of the subject eye with a predetermined elevation angle from below the subject eye with infrared slit light whose longitudinal direction is substantially horizontal to the subject eye;
An imaging mechanism for imaging the anterior segment of the subject's eye illuminated with slit light as a still image;
An ophthalmologic apparatus comprising:   The ophthalmologic apparatus according to claim 1, further comprising a recording unit configured to record an anterior segment of the eye to be inspected that is captured as the still image.   The image processing part which extracts the cornea reflection slit image and iris reflection slit image of an anterior eye part from the image imaged as the said still image, and calculates the angle which both slit images make is provided, or characterized by the above-mentioned. The ophthalmic apparatus according to 2. An ophthalmologic apparatus capable of switching between anterior ocular segment imaging and fundus imaging,
A slit light illumination mechanism for irradiating the anterior ocular segment of the subject eye with a predetermined elevation angle from below the subject eye with infrared slit light whose longitudinal direction is substantially horizontal to the subject eye;
First imaging means for imaging the anterior segment of the eye to be examined;
Second imaging means for imaging the fundus of the eye to be examined,
The first imaging means has a moving image imaging function and a still image imaging function,
When the anterior ocular segment is switched from anterior ocular segment imaging to fundus imaging while moving images are captured along with the anterior ocular slit image by the slit light illumination mechanism, the anterior ocular segment is imaged together with the anterior ocular slit image. Ophthalmic apparatus characterized by being made.   5. The ophthalmologic apparatus according to claim 4, wherein the first imaging unit captures a moving image of the fundus of the eye to be inspected after the anterior segment is captured as a still image.   6. The ophthalmologic apparatus according to claim 4, further comprising recording means for recording an image captured as a still image.   5. An image processing unit is provided that extracts an corneal reflection slit image and an iris reflection slit image of the anterior segment from an image captured as the still image and calculates an angle formed by both slit images. The ophthalmologic apparatus according to any one of 6.