JPH0866364A - Ophthalmic equipment - Google Patents

Abstract

PURPOSE: To prevent the occurrence of a measurement error by detecting eyelashes or an eyelid obstructing an optical path before measurement. CONSTITUTION: A beam from a light source 1 illuminates a ring type light diffuser 2 and is projected on the cornea Ec of an inspected eye for forming a cornea reflection image. Also, the image is sent to an image pick-up element 5 and the image of an inspected eye and the reflected image of the cornea Ec are shown on a TV monitor 16. The form of the cornea reflection image is analyzed with a computer 14 and when eyelashes or an eyelid obstructing an optical path is detected, a warning message is displayed on the monitor 15 together with a measurement value, from a display data memory 12 via a video signal synthesizing means 15. When the message is displayed, a tester moves up or otherwise a testee's eyelid, and operates an input switch 17 to take measurements after the disappearance of the message.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ophthalmologic apparatus used in an ophthalmic clinic or the like.

[0002]

2. Description of the Related Art Conventional ophthalmologic instruments for measurement perform a series of measurements regardless of whether or not eyelashes or eyelids hang on the measurement optical path, and calculate measured values.

[0003]

However, in the above case, there is no means for detecting that the eyelashes or eyelids are suspended on the measurement optical path before the measurement such as observation of the anterior segment or alignment. You may not notice the eyelashes or eyelids hanging on the measurement light path until a measurement error occurs after measurement. In addition, there is a possibility that an error may occur in the measurement value due to the eyelashes and eyelids hanging on the measurement optical path.

The object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide an ophthalmologic apparatus that can detect the lashes and eyelids hanging on the measurement optical path before measurement and ensure the accuracy of measurement.

[0005]

Means for Solving the Problems An ophthalmologic apparatus according to the present invention for achieving the above object is formed by an index projection means for projecting an index on the cornea of an eye to be examined and forming a corneal reflection image by the cornea. And a light-receiving optical system that forms the corneal reflection image on an image sensor, and detects the corneal reflection image during observation or alignment of the anterior segment, and detects that foreign matter is mixed in the detected corneal reflection image. It is characterized in that it has a detecting means for performing, a warning means for giving a warning by the output of the detecting means, and a measuring means for measuring the information of the eye to be examined.

[0006]

The ophthalmologic apparatus having the above-described configuration detects the presence of foreign matter such as eyelashes and eyelids on the measurement optical path by projecting an index on the cornea of the eye to be examined and analyzing the state of the corneal reflection image.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on the illustrated embodiments. FIG. 1 is a configuration diagram of the first embodiment and is an example of a corneal shape measuring apparatus. In the emitting direction from the plurality of light source LEDs 1 to the eye E, a ring-shaped light diffusion plate 2 having a ring shape is arranged in front of the light source LEDs 1. Further, the objective lens 3 is arranged so as to face the eye E to be inspected, and the diaphragm 4 and the image pickup element 5 are sequentially arranged on the optical path 01 behind the objective lens 3. 2 is a front view of the objective lens 3 viewed from the eye E side, and there is a ring-shaped light diffusion plate 2 around the objective lens 3, which serves as a ring-shaped diffused light source, and the cornea Ec of the eye E to be examined. It is designed to illuminate.

The image pickup device 5 includes an image pickup device drive circuit 6, A /
The D converter 7 is sequentially connected to the A / D converter 7 via the image memory 8, the MPU 9, the ROM 10 in which programs and fixed data are written, the RAM 11 that is a readable / writable memory, and the display data memory. A computer 14 including an input / output port 12 and an input / output port 13 is connected. The MPU 9 controls this device, the RAM 11 is used for storing measured value data and used for calculation and processing of the MPU 9, and the display data memory 12 is display data for displaying measured values, warnings, etc. on the television monitor 16. To remember.

The outputs of the image pickup element drive circuit 6 and the display data memory 12 are connected via a video signal synthesizing means 15 to a television monitor 16 for displaying an image of the eye to be inspected, measured values, warnings and the like. The input / output port 13 is connected with an input switch 17 for an examiner to operate the device and a light source adjusting circuit 18 for adjusting the light amount of the light source LED 1, and the light source adjusting circuit 18 is connected with the light source LED 1. .

The light flux from the light source LED 1 illuminates the ring-shaped light diffusion plate 2, and the ring-shaped light diffusion plate 2 is projected as a ring-shaped diffusion light source onto the cornea Ec of the eye E to be inspected, depending on the curvature of the cornea Ec. A corneal reflection image Pc which is a virtual image is formed. at the same time,
This ring-shaped diffused light source illuminates the anterior segment Ef of the eye E to be examined,
An eye image Pe to be inspected is formed.

The reflected light beam from the cornea Ec and the anterior segment Ef passes through the objective lens 3 and the diaphragm 4 and forms an image on the image sensor 5, which is output by the image sensor drive circuit 6 as a video signal Sv.
The video signal Sv is input to the A / D converter 7, converted into a digital signal Sd, and stored in the image memory 8. MPU9
Analyzes the shape of the corneal reflection image Pc in the RAM 11 using the image data stored in the image memory 8 based on the program written in the ROM 10 and fixed data,
Calculate the measured values of the radius of curvature of the eye and the corneal astigmatism. This measured value is stored in the display data memory 12, and the output from the display data memory 12 is input to the video signal synthesizing means 15 together with the video signal Sv and synthesized, and as shown in FIG. Pe and the corneal reflection image Pc are displayed.

If the eyelashes or eyelids hang on the cornea Ec during the measurement, the measured value may not be calculated or the measured value may include an error. When the eyelashes or eyelids are suspended on the cornea Ec, the light flux from the ring-shaped diffuse light source is blocked, and the light amount of a part of the ring image of the corneal reflection image Pc is reduced, or the ring image is missing, or the ring image is lost. Since the width of becomes uneven, before measurement, a ring-shaped corneal reflection image Pc by a ring-shaped diffused light source is formed on the cornea Ec in advance,
By analyzing the shape of the corneal reflection image Pc by the computer 14, it is detected that the eyelashes or eyelids are suspended on the cornea Ec. When such a state is detected, a warning or the like is stored in the display data memory 12, and the video signal synthesizing means 15 is stored.
A warning is displayed on the TV monitor 16 via.

The examiner always observes the television monitor 16 at the time of observing the anterior segment of the eye and at the time of alignment, and if a warning is issued, the examiner takes measures such as raising the eyelids of the examinee so that no warning is given. After that, the input switch 17 is operated to perform the measurement.

It should be noted that an eye refractive power measuring device or an intraocular pressure measuring device may be used instead of the cornea shape measuring device. Further, although the light source for detecting the warning and the light source for the measurement are shared, it is possible to provide them separately.

FIG. 4 is a block diagram of the second embodiment, showing an example of a non-contact tonometer. LEDs for multiple light sources
21 from the light source 21 to the eye E to be examined E
A ring-shaped light diffusion plate 22 having a ring shape is arranged on the front surface of the. Further, a light transmitting member 25 is arranged around the nozzle 24 provided in the cylinder 23 so as to face the eye E to be inspected, and the light transmitting member 25 is provided in the cylinder 23 on the optical path 01 behind the light transmitting member 25. The light transmissive member 26, the lens 27, the half mirror 28, the lens 29, the half mirror 30, and the imaging element 31 are sequentially arranged. The nozzle 24 is a cornea
Air is blown onto Ec, and the light transmitting members 25 and 26 seal the cylinder 23 and transmit the light flux.

A lens 32 and a measuring light source 33 are arranged in the reflection direction of the half mirror 28, and the half mirror 3
A diaphragm 34 and a photo sensor 35 are arranged in the 0 reflection direction. The diaphragm 34 is conjugate with the image of the measurement light source 33 when the cornea Ec has a predetermined corneal curvature, and
The output of the photo sensor 35 is maximized when a predetermined corneal curvature occurs.

The image sensor 31 includes an image sensor drive circuit 36,
The A / D converters 37 are sequentially connected, and the A / D converters 37
Through the image memory 38, the image memory 38, the MPU
39, ROM 40 in which programs and fixed data are written, RAM 41 which is a readable / writable memory,
A computer 44 including a display data memory 42 and an input / output port 43 is connected. Further, the outputs of the image pickup device drive circuit 36 and the display data memory 42 are connected via a video signal synthesizing means 45 to a television monitor 46 which displays an image of the eye to be inspected, measured values, warnings and the like. In addition, MP
U39 controls this device, RAM41 is used for storage of measured value data, calculation and processing of MPU39, and display data memory 42 stores display data for displaying measured values and warnings on the television monitor 46. It is supposed to do.

Further, a photosensor amplifier 47 is connected to the photosensor 35, and the photosensor amplifier 4 is connected.
The output of 7 is connected to the A / D converter 49 together with the output of the pressure sensor 48 that detects the internal pressure of the cylinder 23, and the output of the A / D converter 49 is connected to the input / output port 43. Further, an input switch 50 and a rotary solenoid drive circuit 51 for an examiner to operate this device are connected to the input / output port 43, and the rotary solenoid 52 connected to the rotary solenoid drive circuit 51 is connected to the cylinder 23. The piston 53 provided is driven.

The light flux from the light source LED 21 illuminates the ring-shaped light diffusion plate 22, and the ring-shaped light diffusion plate 22 is projected as a ring-shaped diffusion light source on the cornea Ec of the eye E to be inspected, and the cornea Ec.
A corneal reflection image Pc, which is a virtual image corresponding to the curvature of, is formed. At the same time, the ring-shaped diffused light source illuminates the anterior segment Ef of the subject's eye E to form the subject's eye image Pe.

The reflected light fluxes from the cornea Ec and the anterior segment Ef pass through the light transmissive members 25 and 26, the lens 27, the half mirror 28, the lens 29 and the half mirror 30 to form an image on the image sensor 31, and the image sensor 31. The driving circuit 36 outputs the video signal Sv. The video signal Sv is input to the A / D converter 37, converted into a digital signal Sd, and stored in the image memory 38. The MPU 39 uses the image data stored in the image memory 38 in the RAM 41 on the basis of the program and fixed data written in the ROM 40 to generate the corneal reflection image Pc.
Analyze the shape of.

The luminous flux from the measuring light source 33 passes through the lens 32, is reflected by the half mirror 28, and is reflected by the lens 2
7, through the light transmissive member 26 and the nozzle 24, it is projected onto the cornea Ec. The projected light flux is reflected on the cornea Ec, passes through the light transmissive members 25, 26, the lens 27, the half mirror 28, and the lens 29, is reflected by the half mirror 30, and the diaphragm 34.
And is projected onto the photosensor 35. The output of the photo sensor 35 is amplified by the photo sensor amplifier 47 and input to the A / D converter 49.

At the time of measuring the intraocular pressure, the rotary solenoid drive circuit 51 drives the rotary solenoid 52, the rotary solenoid 52 drives the piston 53, and the nozzle 24
Blow air onto the cornea Ec from. When the cornea Ec is flattened and deformed by a predetermined amount and the cornea Ec reaches a predetermined corneal curvature, the output of the photo sensor 35 becomes maximum. Therefore, the internal pressure of the cylinder 23 at that time is detected by the pressure sensor 48, and The result is passed through the A / D converter 49 and the input / output port 43,
It is input to the computer 44 and analyzed to calculate the intraocular pressure of the eye E to be inspected. The measured value is stored in the display data memory 42, and the output from the display data memory 42 is input to the video signal synthesizing means 45 together with the video signal Sv to be synthesized, and the subject eye image Pe and the corneal reflection image Pc are displayed on the television monitor 46. Is projected.

During this measurement, if eyelashes or eyelids hang on the cornea Ec, air cannot be reliably blown to the cornea Ec, and the measured value cannot be calculated or the measured value has an error. May be included. When the eyelashes or eyelids hang on the cornea Ec, the light flux from the ring-shaped diffused light source is blocked as in the case of the first embodiment, so that the effective diameter of the cornea Ec from which the air is blown from the nozzle 24 is reduced. By forming a ring-shaped corneal reflection image Pc by a ring-shaped diffused light source around and analyzing the shape of the corneal reflection image Pc by the computer 44, it is detected that eyelashes and eyelids are hanging on the cornea Ec. . When such a state is detected, a warning or the like is stored in the display data memory 42 together with the measured value and is displayed on the television monitor 46 via the video signal synthesizing means 45.

The examiner always observes the television monitor 46 at the time of observing the eye and at the time of alignment and, if a warning is given, takes measures such as raising the eyelid of the examinee, and after the warning is not given. The input switch 50 is operated to perform the measurement.

Although the ring-shaped diffused light source by the ring-shaped light diffuser plate 22 is used, an arc-shaped or linear light source only on the upper side may be used as long as it is limited to eyelash detection. Also,
In the first and second embodiments, the warning is displayed on the television monitor 1
Instead of displaying 6 and 46, a warning light may be separately provided and a buzzer or the like may sound. Furthermore, although the ring-shaped diffused light source by the ring-shaped light diffuser plates 2 and 22 is used, a plurality of spot-shaped light sources may be used.

[0026]

As described above, the ophthalmologic apparatus according to the present invention projects the index on the cornea of the eye to be inspected before the measurement, analyzes the state of the corneal reflection image, and confirms the presence of foreign matter on the measurement optical path. By detecting, measurement error can be prevented.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram of a ring-shaped diffused light source viewed from the eye side to be examined.

FIG. 3 is an explanatory diagram of a television monitor on which an eye image and a corneal reflection image are displayed.

FIG. 4 is a configuration diagram of a second embodiment.

[Explanation of symbols]

 1, 21 LED for light source 2, 22 Ring-shaped light diffusing plate 5, 31 Imaging device 8, 38 Image memory 15, 45 Video signal synthesizing means 16, 46 Television monitor 24 Nozzle 35 Photo sensor

Claims (3)

[Claims] 1. An index projection means for projecting an index on a cornea of an eye to be inspected to form a corneal reflection image by the cornea, a light receiving optical system for forming the formed corneal reflection image on an image pickup element, and an anterior ocular segment. Detecting the corneal reflection image at the time of observation or alignment, detecting means for detecting that a foreign substance is mixed in the detected corneal reflection image, warning means for warning by the output of the detecting means, and the eye to be examined. An ophthalmologic apparatus comprising: a measuring unit that measures information. 2. The ophthalmologic apparatus according to claim 1, wherein the measuring means is a cornea shape measuring device. 3. The ophthalmic device according to claim 1, wherein the ophthalmic device is an intraocular pressure measuring device.