JPH07124112A - Ophthalmological device - Google Patents

Abstract

PURPOSE:To precisely perform alignment in the visual line direction of an eye to be inspected and perform measurement in an appropriate operating distance state. CONSTITUTION:The eye E to be inspected is irradiated with luminous flux from a light source 7 for measurement, and reflected light is converged on an alignment light receiving part 15 via an objective lens 4, etc. When a testee depresses a measurement start button 34, a motor 27 with gear is driven, and an objective unit 10 reciprocates by a specific moving stroke in the visual line direction of the eye E to be inspected, then, the optimum alignment position can be detected by the alignment light receiving part 15. A rotary solenoid 23 is driven at that position, and compressed air is sprayed on the cornea Ec of the eye E to be inspected from a nozzle 1, then, the cornea Ec is deformed. Such deformed state is detected by a deformation detection light receiving part 18, and the internal pressure of an air chamber 5 at that time is ready by a pressure sensor 36, then, it is converted to an intraocular tension value.

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 ophthalmology clinic, an eyeglass store, or the like.

[0002]

2. Description of the Related Art In a conventional ophthalmologic apparatus, alignment in the working distance direction is performed by projecting a light beam on an eye to be inspected, receiving the reflected light beam, and monitoring the positional deviation by a television monitor or a direct-viewing mirror, so that the examiner can detect the position. The sliding table equipped with the eye part is moved and adjusted. In addition, in an ophthalmologic apparatus that allows the subject himself to examine the eye, the subject adjusts his or her face in the working distance direction to find an appropriate working distance.

Further, as in Japanese Patent Laid-Open No. 1-300928 and Japanese Patent Laid-Open No. 1-300929, a part of the measuring unit can be automatically aligned by an auto-alignment mechanism, and Japanese Patent Laid-Open No. 4-9138. As described above, there are known ones that set an appropriate working distance by a member that abuts around the eye to be inspected, and further that a member that abuts a part of the face of the subject can be automatically aligned by an automatic alignment mechanism. There is.

[0004]

However, in the conventional ophthalmologic apparatus in which the examiner adjusts the working distance while observing the alignment state of the eye to be inspected, the three directions of up, down, left and right, and the depth are sequentially adjusted, so that a severe alignment is required. The required ophthalmologic apparatus is time-consuming and inefficient for optometry.

Further, in order to receive the reflected light beam from the eye to be inspected and perform automatic alignment, a system for detecting positional deviations in the three directions of the X, Y, and Z axes is required, and the driving mechanism for moving in the three directions is complicated. Since this is a difficult technique, there is a problem that the manufacturing cost of the device will be significantly increased.

Further, it is a more difficult technique for the examinee to operate the subject's eye up and down, left and right, to adjust the distance in the visual axis direction. In particular, in an ophthalmologic apparatus that requires delicate alignment, even if the positions in the vertical and horizontal directions are once aligned, the vertical, horizontal, and lateral directions are displaced when aligned in the visual axis direction, and the alignment in the visual axis direction must be performed again. A vicious cycle of not becoming possible occurs. Further, when setting the appropriate working distance by a member that abuts around the eye to be inspected, the position of the member must be adjusted for each subject, and it is completely unsuitable when the eye to be inspected changes one after another. .

It is an object of the present invention to provide an ophthalmologic apparatus which solves the above-mentioned problems, accurately aligns the eye to be examined in the visual axis direction, and can easily obtain an appropriate working distance.

[0008]

In order to achieve the above object, an ophthalmologic apparatus according to the present invention comprises moving means for changing a distance between an eye to be inspected and an optical system in a visual axis direction, and a visual axis of the moving means. And a control means for starting the optometry when an appropriate working distance state is reached during the directional movement stroke.

[0009]

In the ophthalmologic apparatus having the above structure, the distance between the eye to be inspected and the optical system is adjusted by moving the optical system including the objective lens or the member contacting the face of the subject in the visual axis direction, The control is performed so as to start the optometry after reaching the proper working distance state.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on the illustrated embodiments. FIG. 1 shows a block diagram of the first embodiment, which is an embodiment of a tonometer of the type measured by the subject himself. A nozzle 1 is provided in the center on the optical path O in front of the eye E to be inspected, and is supported by a concave mirror 2 that transmits infrared light and a perforated glass 3. An air chamber 5 is formed between the perforated glass 3 and the objective lens 4, and on the optical path O at the center of the air chamber 5,
A dichroic mirror 6 is provided. A measurement light source 7 that emits near-infrared light and a projection lens 8 are arranged in the 90-degree incidence direction of the dichroic mirror 6. These optical members are fixed in the sealing member 9 and constitute the objective unit section 10.

A relay lens 11 and a dichroic mirror 12 are arranged on an optical path O behind the objective unit section 10, and an alignment light receiving section 15 including an aperture 13 and a light receiving element 14 is further provided. Further, in the reflection direction of the dichroic mirror 12 with respect to the optical path O, the deformation detection light receiving unit 1 including the aperture 16 and the light receiving element 17 is formed.
8 are provided. Further, a light source 19 for illuminating the anterior segment is arranged around the nozzle 1.

Aperture 13 of alignment light receiving section 15
Is arranged so as to be in a position conjugate with the corneal reflection image by the measurement light source 7 at the time of proper alignment, and the aperture 16 of the deformation detection light receiving portion 18 is blown by air onto the cornea Ec of the eye E to be inspected. It is arranged so that the amount of light is maximized.

A cylinder 21 is provided in the air chamber 5 of the objective unit 10 via a flexible tube 20.
A pump for sending compressed air is connected to the piston 22 and a rotary solenoid 23 is connected to the piston 22 via a link mechanism.

On the other hand, a rack 24 is formed below the sealing member 9 in parallel with the optical path O, the rack 24 meshes with a gear 25, and the gear 25 is connected to a pulley 28 of a geared motor 27 via a belt 26. Has been done.

FIG. 2 is a front view seen from the side of the subject, in which the anterior ocular segment image Ef illuminated on the anterior ocular segment illumination light source 19 is the concave mirror 2.
Is reflected in. In addition, a bearing 29 is provided on the side surface of the sealing member 9.
a, 29b are attached, and guide shafts 30a, 30 are provided therein.
b is inserted, and the objective unit section 10 is guided parallel to the optical path O.

On the other hand, the rotary solenoid 23 and the geared motor 27 are connected to the CPU 33 via the rotary solenoid driver 31 and the motor driver 32, respectively, and the measurement start button 34 is also connected to the CPU 33. The outputs of the light receiving elements 14 and 17 are both connected to the signal processing unit 35, and the output of the pressure sensor 36 for measuring the pressure of the air chamber 5 is also connected to the signal processing unit 35. Connected with.

The luminous flux emitted from the measuring light source 7 at the time of measuring the intraocular pressure is transmitted through the projection lens 8 to the dichroic mirror 6.
Reflected by the cornea Ec of the eye E to be examined through the tube of the nozzle 1.
Is irradiated. Infrared light of the light flux reflected by the cornea Ec passes through the concave mirror 2 around the nozzle 1 and the perforated glass 3 and becomes a parallel light flux by the objective lens 4. This parallel light flux passes through the relay lens 11, and part of it is the dichroic mirror 1.
After passing through 2, the light is focused on the alignment light receiving unit 15.

The examiner looks at the concave mirror 2 that reflects visible light, and adjusts the nozzle 1 so that the nozzle 1 is at the center of the pupil of the examinee's eye E. By pressing the measurement start button 34 after confirming that the vertical and horizontal positions match, the CPU 33 sends a drive command for the motor 27 to the motor driver 32, and the geared motor 27 is driven. The gear 25 is rotated by the drive of the motor 27 via the belt 26, and the objective unit 10
Makes one round trip in parallel with the optical path O for a predetermined movement path.

During the predetermined movement process, the light quantity of the light receiving element 14 of the alignment light receiving section 15 increases, and the light quantity value sent to the CPU 33 through the signal processing section 35 for A / D conversion is larger than a predetermined level. If so, the CPU 33 determines that the alignment in the working distance direction matches, and sends a drive command to the solenoid driver 31 to drive the rotary solenoid 23. The rotary solenoid 23 drives the piston 22 and blows air onto the subject's eye E as described above. Due to this air blowing, the cornea Ec is flattened, and the pressure inside the air chamber 5 when the amount of light received by the light receiving element 17 of the deformation detection light receiving unit 18 becomes maximum in a predetermined deformation state,
The pressure sensor 36 reads and converts it into an eye pressure value.

In this embodiment, when the eye E to be examined is aligned in the vertical and horizontal directions, the measurement start button 34 is pressed to start the predetermined movement process. However, the measurement start button 34 is pressed to start the predetermined movement process first. The objective unit section 10 is not limited to one round trip.
It is also possible to use a control system in which the subject performs alignment in the vertical and horizontal directions during the reciprocal movement of the robot, and performs measurement when the alignment light receiving unit 15 detects the proper working distance state.

Although not shown in FIG. 1, a mechanism for detecting the moving distance of the objective unit 10 is provided to detect and store the position of the first measurement, so that the same eye E can be detected twice. In the case of the above measurement, the drive of the geared motor 27 may be controlled to shorten the predetermined moving distance range and shorten the measurement time after the second measurement. Further, the internal fixation lamp may be arranged so as to be reflected on the optical path O, and the visual axis of the eye E to be examined may be sufficiently fixed to stabilize the measurement.

3 and 4 show a second embodiment in which the objective unit 10 is manually operated by using a crank mechanism instead of driving by the motor 27 as means for moving the eye E in the visual axis direction. , Shows an example in which the configuration of the device is simplified. That is, a linear bearing 38 that can move the objective unit 10 in parallel with the optical path O with respect to the fixed base 37 is provided below the objective unit 10. A link member 39 is connected to the rear side of the linear motion bearing 38,
The other end of the link member 39 is connected to the crank member 40. The crank member 40 can freely rotate via a shaft 40a in a bearing portion 37a protruding from the fixed base 37, and a rotary knob 41 is provided on an extension of the shaft 40a.
Is attached. Further, the fixed base 37 has a protrusion 37.
b and 37c are provided and serve as stoppers for the movement of the objective unit section 10.

In the tonometer having the above-described structure, the examinee looks at his or her eye E with the concave mirror 2 as in FIG. When the person confirms, the rotary knob 41 is manually rotated once. Here, the objective unit 10 makes one reciprocation of a predetermined movement stroke, and when the proper working distance is reached while the vertical and horizontal alignments are properly maintained, the light amount of the alignment light receiving unit 15 becomes maximum, and thus the intraocular pressure measurement is performed. .

FIG. 5 shows the optical system of the tonometer according to the third embodiment. The objective unit section 10 of FIG. 1 to which a light source 50, a mask 51, and a line sensor 52 are added is an objective unit section 10 '. These additional optical systems form a working distance detection system 53 that detects a working distance. A dichroic mirror 54 is inserted in a parallel light flux portion behind the objective lens 4 to split the light flux, and television lenses 55 and 56 and a CCD camera 57 are arranged in the transmission direction of the dichroic mirror 54.
Are arranged, and in the reflection direction of the dichroic mirror 54, the relay lens 58, the aperture 16, and the light receiving element 17 are arranged.
The deformation detection light receiving unit 18 composed of is arranged. The output of the light receiving element 17 and the output of the CCD camera 57 are connected to the signal processing unit 59.

With the above-described structure, the luminous flux emitted from the measurement light source 7 passes through the projection lens 8, is reflected by the dichroic mirror 6, passes through the nozzle 1, and is irradiated onto the cornea Ec of the eye E to be examined. The reflected light flux of the cornea Ec passes through the concave mirror 2, passes through the perforated glass 3 and the objective lens 4, and becomes a parallel light flux. The light flux reflected by the dichroic mirror 54 is condensed by the relay lens 58 and received by the light receiving element 17. Also,
The light flux that has passed through the dichroic mirror 54 is condensed by the television lenses 55 and 56 and imaged on the CCD camera 57.

Light source 5 provided in the objective unit section 10 '
The light flux from 0 is formed into a slit shape by the mask 51,
The light flux reflected by the cornea Ec is received by the line sensor 52,
The proper working distance between the cornea Ec and the objective unit 10 'can be detected by the line sensor 52. Further, the CCD camera 57 can observe the corneal reflection image of the measurement light source 7 and the anterior segment image of the eye E, and the alignment of the eye E in the vertical and horizontal directions is CC.
It is detected by the video signal of the D camera 57. And
When the corneal reflection image of the measurement light source 7 is detected in a predetermined area on the light receiving surface of the CCD camera 57, the objective unit section 10 'starts a predetermined reciprocating stroke. When the proper working distance is detected by the working distance detection system 53 of the objective unit 10 ', the first
The rotary solenoid 23 is driven and air is blown to the eye E to be inspected by pushing up the piston 22 in the same manner as in the embodiment of FIG.

In this embodiment, since the working distance between the eye E to be examined and the objective unit section 10 'can be detected, the objective unit section 1 can be detected.
When 0 ′ comes close enough to come into contact with the eye E during the predetermined movement process, safety can be ensured by providing a control circuit or control software that avoids contact with the objective unit 10 ′.

FIG. 6 shows a fourth embodiment in which the entire keratometer measuring unit 60 is moved in the visual axis direction of the eye E to be inspected. In the keratometer measurement unit 60, the eye E to be inspected
An objective lens 61, a dichroic mirror 62, camera lenses 63 and 64, a diaphragm 65, and a two-dimensional CCD camera 66 are disposed on the optical path O in front of the. Further, the liquid crystal display 6 is arranged in the reflection direction of the dichroic mirror 62.
7 are arranged, and four anterior ocular segment illumination light sources 68 are provided around the objective lens 61. And two-dimensional CC
The output of the D camera 66 is connected to the signal processing unit 69 and further connected to the CPU 70.

A linear motion bearing 71 is formed in the lower portion of the keratometer measuring unit 60, a belt 72 is suspended from the front end to the rear end of the linear motion bearing 71, and further provided below the linear motion bearing 71. The belt 72 is wound around the roller 74 and the geared roller 75 supported by the fixed base 73. The geared roller 75 is a drive motor 76.
The fixed base 73 is engaged with the linear motion bearing 71.
Micro switches 77 and 78 for confirming the positions of the frontmost point and the last point of movement of are attached.

With the above-described structure, the light fluxes emitted from the four anterior ocular segment illuminating light sources 68 to the cornea Ec are reflected by the cornea Ec, transmitted through the objective lens 61 and passed through the camera lenses 63, 64 and the diaphragm 65. An image is formed on the two-dimensional CCD camera 66. The anterior ocular segment image is also formed on the two-dimensional CCD camera 66, and the image is displayed on the liquid crystal display 67, reflected by the dichroic mirror 62 and projected on the fundus of the eye E to be examined. The anterior segment can be confirmed.

When the subject aligns in the vertical and horizontal directions while observing his anterior segment of the eye, the two-dimensional CCD camera captures the corneal reflection image of the anterior segment illuminating light source 68 with four out-of-focus images. 66 receives the light, and the signal processing unit 6 receives the video signal.
9 performs position detection in the vertical and horizontal directions. When it is confirmed that the detected position is proper, the motor 76 is driven, the rotation is transmitted to the geared roller 75, the belt 72 is moved, and the keratometer measurement unit 60 is moved toward the eye E to be examined in the visual axis direction. Moving. A micro switch 77 is arranged at the foremost point of movement, and when the measuring unit 60 contacts, the motor 76 reversely rotates and tries to return to the original position. Also, the micro switch 7
The end point of the predetermined travel process can be confirmed by 8.

During this process, the sizes and contrasts of the four light source images are detected from the video signal output of the two-dimensional CCD camera 66, and the signal processing unit 69 and the CPU 70 determine that the working distance is appropriate. The position of the center of each corneal reflection image of the four anterior segment illumination light sources 68 is calculated, and the radius of curvature of the cornea Ec is obtained. In this way, even if the optical system does not have the parallel light flux portion, the measurement can be continued by moving the entire measuring unit 60.

Further, in the third and fourth embodiments, since the television camera for observing the anterior segment of the eye E to be inspected is built in, not only the ophthalmic equipment for self-eye examination but also the ophthalmologic equipment measured by the examiner. Can also be applied to, which can shorten the alignment time and improve the operability.

FIG. 7 shows a block diagram of the fifth embodiment. Up to the above-described fourth embodiment, the optical system including the objective lens 4 is moved with respect to the eye E to perform the alignment of the eye E in the visual axis direction, but in the fifth and subsequent embodiments. ,
On the contrary, the forehead contact member is moved, that is, the eye E to be inspected is moved with respect to the optical system to perform the alignment in the visual axis direction.

In FIG. 7, a measurement optical system and a detection system,
The compressed air blowing mechanism and the control mechanism are the same as in the first embodiment. Above the sealing member 9 of the objective unit 10,
A screw shaft motor 80 is fixed in parallel with the optical path O via a fixing plate 81. Screw shaft 80a of the motor 80
Engages with the female screw portion 82, and the female screw portion 82 is fixed to the support shaft 84 of the forehead rest 83. In addition, the support shaft 84
Are held by bearings 85a and 85b, and these bearings 8
The bearing base 86 to which 5a and 85b are attached is fixed to the objective unit section 10. The output of the CPU 33 is connected to the motor 80 via the motor driver 32.
FIG. 8 is a front view seen from the subject side, and the anterior ocular segment image Ef emitted from the anterior ocular segment illumination light source 19 is reflected on the concave mirror 2 around the nozzle 1.

With the above-described structure, the intraocular pressure measurement is performed in the same manner as in the first embodiment, the subject looks at the concave mirror 2 to perform the vertical and horizontal position adjustment, and presses the measurement start button 34. CPU
33 sends a drive command to the motor driver 32 and the motor 80
Is driven. By driving the motor 80, the forehead support shaft 84 makes one reciprocation of a predetermined movement path in parallel with the optical path O via the female screw portion 82. The subject follows the movement of the forehead support 83, and this predetermined movement process is performed in a state where the forehead is in contact with the forehead support 83.

When the working distance alignment becomes proper during the predetermined movement stroke, the rotary solenoid 23 is driven and air is blown from the nozzle 1 to the eye E to be inspected. Accordingly, the predetermined deformation state of the cornea Ec is detected by the light receiving element 17 of the deformation detecting unit 18, the internal pressure of the air chamber 5 at this time is read by the pressure sensor 36, and the intraocular pressure value is calculated.

A mechanism for detecting the moving distance of the forehead pad 83 when the forehead pad 83 is in the proper alignment state is started by starting a predetermined movement process while applying the forehead pad 83.
The reduction of the measurement time from the detection position of the second measurement onward for the second measurement onward and the stabilization of the measurement by fixing the visual axis by providing an internal fixation lamp can be performed in the same manner as in the first embodiment. is there.

FIGS. 9 and 10 show a sixth embodiment, which uses a crank mechanism as in the second embodiment and a fifth embodiment.
The forehead rest is moved in the same manner as in the above embodiment. A linear bearing 90 that can move in parallel with the optical path O is provided above the objective unit 10. A slide member 91 penetrates through the linear motion bearing 90, and a crank member 92 is rotatably fixed to the rear end portion thereof. A forehead support 93 is fixed to the front end of the slide member 91. The link member 94 connected to the crank member 92 includes a bearing portion 91a protruding from the slide member 91,
The shaft 94a provided on 91b can be freely rotated, and a rotary knob 95 is fixed on the extension of the shaft 94a. Bearing portions 91a, 9 of the slide member 91
A balance spring 96 is attached between 1b and the linear motion bearing 90, and the force of the subject to contact the forehead with the forehead support 93 is absorbed by the balance spring 96 to reduce the manual load during a predetermined movement process. It is like this.

In the above-described structure, as in the fifth embodiment, the subject looks at the anterior segment of the eye reflected on the concave mirror 2 while abutting the forehead against the forehead rest 93, and aligns in the vertical and horizontal directions. . Here, when the subject confirms that they are almost matched, he / she rotates the rotary knob 95 once. With this, the forehead support 93
When a proper working distance is reached while the upper, lower, left, and right alignments are properly maintained, the light amount of the alignment light receiving unit 15 becomes maximum, and the deformation detection light receiving unit 18 measures the intraocular pressure.

In the fifth and sixth embodiments, the forehead rests 83 and 93 have been taken as examples of the members for contacting a part of the face of the subject, but a tubular member or a chin rest member for contacting around the eyes. However, the same effect can be obtained.

[0042]

As described above, the ophthalmologic apparatus according to the present invention can shorten the alignment time when aligning the apparatus with respect to the eye to be inspected, thus placing a heavy burden on the subject. And the operability can be improved. Further, as compared with the automatic alignment system, the drive mechanism and the position detection system can be simplified, and the size and cost of the device can be reduced. In particular, in the case of an apparatus in which the examinee himself / herself examines the eye, it can be applied to household and portable applications.

[Brief description of drawings]

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

FIG. 2 is a front view seen from the subject side.

FIG. 3 is a configuration diagram of a second embodiment.

FIG. 4 is a front view seen from the subject side.

FIG. 5 is a configuration diagram of a third embodiment.

FIG. 6 is a configuration diagram of a fourth embodiment.

FIG. 7 is a configuration diagram of a fifth embodiment.

FIG. 8 is a front view seen from the subject side.

FIG. 9 is a configuration diagram of a sixth embodiment.

FIG. 10 is a front view seen from the subject side.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Nozzle 2 Concave mirror 3 Perforated lens 4 Objective lens 7, 19, 50, 68 Light source 10 Objective unit section 15 Alignment light receiving section 18 Deformation detection light receiving section 23 Rotary solenoid 24 Rack 27, 76, 80 Motor 33, 70 CPU 34 Measurement start Buttons 35, 59, 69 Signal processing units 38, 71, 82, 90 Linear motion bearings 56, 66 CCD cameras 83, 93 Forehead support

Claims (2)

[Claims] 1. A moving means for changing the distance between the eye to be inspected and the optical system in the visual axis direction, and a control means for starting the eye examination when an appropriate working distance state is reached during a moving stroke of the moving means in the visual axis direction. An ophthalmologic apparatus characterized by having. 2. The ophthalmologic apparatus according to claim 1, further comprising: a detecting unit that detects a moving distance of the moving unit; and a changing unit that changes a predetermined moving distance range according to an output of the detecting unit.