JP2001275985A - Ophthalmological apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ophthalmological apparatus capable of perform alignment by efficiently making use of an automatic alignment function even when an examined eye is not in a good condition to improve an alignment working and reduce the burden of a subject. SOLUTION: In the ophthalmological apparatus, when a first X-Y alignment detection optical system 40 judges that the alignment state of an apparatus main body S does not meet with a predetermined positional reference, the main body S is moved based on the result of the first X-Y alignment detection optical system 40. When the first and second X-Y alignment detection optical systems 40 and 90 judges that the alignment state of the main body S meets with the positional reference and does not meet with a luminous quantity reference, the main body S is moved within a prescribed area in an X-Y plane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention automatically performs alignment of an apparatus main body provided with an optical system for measurement, photographing, and the like with respect to an eye to be examined prior to measurement of an intraocular pressure, photographing of a fundus, and the like. The present invention relates to an ophthalmologic apparatus having a function.

[0002]

2. Description of the Related Art Conventionally, as an ophthalmologic apparatus having a so-called automatic alignment function, an alignment index light is projected on an eye to be inspected, and a cornea reflected light beam is guided to a position detection sensor, and the apparatus body (measurement unit or the like) is used. ) Is automatically moved and automatic alignment is performed by confirming the light amount of the corneal reflected light beam with a light amount detection sensor (for example, see Japanese Patent Application Laid-Open No. H11-318828).

[0003] In such an ophthalmologic apparatus, an examiner first operates a joystick or the like while looking at a viewfinder or a monitor to manually move the apparatus main body, and roughly performs alignment of the apparatus main body with the eye to be examined. When this rough alignment is done, the above automatic alignment function is activated,
The alignment is completed on condition that the position detection sensor determines that the alignment state of the apparatus main body satisfies a predetermined position criterion, and that the light amount detection sensor determines that the alignment state satisfies a predetermined light amount criterion. It is regarded. And after this alignment is complete,
Measurement and the like by the apparatus main body are automatically started.

[0004]

However, for example, when the corneal surface of the eye to be examined is rough and the condition is not good, a plurality of light spots are supposed to be detected as one corneal reflected light beam. A light spot to be detected, a light spot to be clearly detected may be blurred, or a light spot having a shape different from a predetermined shape may be detected. In such a case, the function of the ophthalmologic apparatus having the automatic alignment function does not operate normally, and there is a possibility that measurement, photographing, or the like is started in a state where the apparatus main body is moved to an inappropriate position.

Alternatively, in the above-described configuration in which the measurement and the like are not started unless the completion of the alignment is determined by both the position detection sensor and the light amount detection sensor, it is possible to avoid such a measurement or the like in an uncompleted alignment state. However, if the measurement is not carried out as it is, the operation is interrupted, so that it is necessary to perform alignment again from the beginning. Such re-execution of automatic alignment may cause the same result again, and even in such an alignment uncompleted state, the apparatus body is driven to a position close to the alignment completed position to some extent.
It is desirable to effectively use the results up to that point without repeating the same automatic alignment procedure again from the viewpoint of improving the efficiency of the alignment work and reducing the burden on the subject.

The present invention has been made in view of the above circumstances, and even if the condition of the eye to be examined is not good, it is possible to effectively utilize the automatic alignment function to perform alignment. It is an object of the present invention to provide an ophthalmologic apparatus capable of improving efficiency and reducing a burden on a subject.

[0007]

According to an aspect of the present invention, there is provided an ophthalmologic apparatus which requires alignment of a main body of the apparatus with an eye to be examined. An alignment index projection system for projecting the alignment index light, a movement control means for controlling the movement of the apparatus main body, and a corneal reflected light flux of the alignment index light incident on a position detecting element capable of detecting the center of gravity of the incident light flux. First detecting means for detecting the alignment state of the apparatus main body, and whether the alignment state detected by the first detecting means satisfies a predetermined position criterion defined based on the alignment completion position of the apparatus main body. First judging means for judging whether or not the corneal reflected light beam is incident on a light amount detecting element capable of detecting the light amount of the incident light beam, and aligning the apparatus main body. A second detecting means for detecting a contact state, and a second determining means for determining whether or not the alignment state detected by the second detecting means satisfies a predetermined light amount standard. When it is determined by the first determination unit that the alignment state does not satisfy the position criterion, the apparatus main body is moved based on the detection result of the first detection unit, and the alignment state satisfies the position criterion. However, when it is determined by the first determination means and the second determination means that the light amount standard is not satisfied, the apparatus main body is moved within a predetermined area.

According to a second aspect of the present invention, in the ophthalmologic apparatus according to the first aspect, when the movement control means moves the apparatus main body within the predetermined area, the alignment state is based on the light amount reference. When it is determined that the condition is satisfied, measurement or photographing by the apparatus main body is automatically started.

According to a third aspect of the present invention, in the ophthalmologic apparatus according to the second aspect, when the measurement or photographing by the apparatus main body is automatically started, the measurement or photographing is performed. The position of the apparatus body at that time is stored as the alignment completion position, and the position reference is newly defined based on the stored alignment completion position.

According to a fourth aspect of the present invention, in the ophthalmologic apparatus according to the first aspect, the alignment state is the light amount reference even though the movement control means moves the apparatus main body within the predetermined area. If it is not determined that the condition is satisfied, the apparatus main body is manually moved to perform alignment, and when the alignment is completed and measurement or imaging by the apparatus main body is started, the measurement or imaging is performed. The position of the apparatus main body when the operation is performed is stored as the alignment completion position, and the position reference is newly defined based on the stored alignment completion position.

According to a fifth aspect of the present invention, there is provided an ophthalmologic apparatus which requires alignment of the apparatus main body with respect to an eye to be examined, an alignment index projection system for projecting an alignment index light toward a cornea of the eye to be inspected, Movement control means for controlling the movement of the apparatus main body, and first detection for detecting the alignment state of the apparatus main body by causing the corneal reflection light beam of the alignment index light to enter a position detecting element capable of detecting the center of gravity of the incident light beam. Means, and first determination means for determining whether the alignment state detected by the first detection means satisfies a predetermined position criterion defined based on the alignment completion position of the apparatus body, When the apparatus body is manually moved and alignment is performed, and when the alignment is completed and measurement or imaging by the apparatus body is started, The position of the apparatus main body when the measurement or photographing is being performed is stored as the alignment completion position, and the position reference is newly defined based on the stored alignment completion position. At the time of the next measurement or photography by the device body,
The alignment is performed by moving the apparatus body so that the first determination unit determines that the alignment state satisfies the newly defined position reference.

According to a sixth aspect of the present invention, in the ophthalmologic apparatus according to the fifth aspect, the alignment completion position is stored in association with an individual ID of the subject, and the movement control means responds to the ID. And moving the apparatus body to perform alignment.

[0013]

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

FIG. 1 is a side view showing an alignment driving mechanism of an intraocular pressure measuring apparatus which is an example of an ophthalmologic apparatus according to the present invention, and FIG. 2 is a plan view thereof. This alignment driving mechanism is a fixed base 10 having a power supply (not shown) built therein.
Control lever 102 such as joystick on 0
Is provided on a gantry 101 which can be moved back and forth and left and right by the operation of, a vertical (Y direction) moving mechanism, a horizontal (X direction)
It comprises a moving mechanism and a forward / backward (Z direction) moving mechanism. The tonometry apparatus has an automatic mode for automatically performing alignment and measurement and a manual mode for manual operation. The control lever 102 is provided with a manual switch 103 used as a measurement start switch in the manual mode. ing.

The vertical moving mechanism is constituted by a motor 104 for lifting and lowering provided on the upper part of the gantry 101 and a column 105 held on the gantry 101 so as to be able to move up and down (Y direction) (that is, to be able to move up and down). Have been. Motor 1
04 and the support 105 are connected by a pinion and a rack (not shown). The column 105 is moved up and down by a motor 104, and a table 106 is provided at the upper end of the column 105.
Is provided.

The horizontal moving mechanism includes a column 107 and a motor 108 provided on a table 106, and a table 1 held at the upper end of the column 107 so as to be slidable in the left and right directions (X direction).
09 and a rack 11 provided at one end of the table 109.
0 and the rack 110 provided on the output shaft of the motor 108.
And a pinion 111 that meshes with.

The front-rear movement mechanism includes a motor 112 and a support 113 provided on the upper part of the table 109,
2 and a pinion 114 provided on the output shaft
And a case 115 of the apparatus main body S provided at the upper part of the apparatus. The case 115 is slidably held back and forth (Z direction), and a rack 116 is provided on a side of the case 115, and the rack 116 is engaged with the pinion 114.

The motors 104, 108 and 112 are driven and controlled by a control signal output from a control circuit 80 described later. The motor 104 is used for automatically aligning the apparatus main body S in the Y direction. Is used for automatically aligning the apparatus body S in the X direction, and the motor 112 is used for automatically aligning the apparatus body S in the Z direction. As the motors 104, 108 and 112, for example, stepping motors (pulse motors) capable of position control are used.

FIGS. 3 and 4 are a side view and a plan view of the optical system housed in the case 115. FIG. As shown in FIGS. 3 and 4, the apparatus main body S includes an anterior ocular segment observation optical system 10 for observing an anterior segment of the eye E, alignment detection in the XY directions (up, down, left, and right directions) and intraocular pressure measurement Light (XY alignment index light) for detecting the amount of corneal deformation of the eye E by blowing air for the eye E
The XY alignment target projection optical system 20 projects the fixation target onto the eye E, the XY alignment target projection optical system 20 projects the fixation target onto the eye E, and the XY alignment target light reflected from the cornea C. A first XY alignment detecting optical system 40 for detecting a positional relationship between the apparatus main body S and the cornea C in the XY directions, and a cornea C by receiving reflected light of the XY alignment index light from the cornea C and blowing air. A corneal deformation detecting optical system 50 for detecting the amount of deformation of the corneal, and a Z alignment target projection for projecting target light (Z alignment target light) for alignment detection in the Z direction (front-back direction) from the oblique direction with respect to the cornea C. The apparatus body S and the cornea C receive the optical system 60 and the reflected light of the Z alignment index light from the cornea C from directions symmetrical with respect to the optical axis of the anterior ocular segment observation optical system 10.
A Z-alignment detection optical system 70 for detecting the positional relationship in the Z direction, and a second XY for receiving the reflected light of the XY alignment index light from the cornea C and detecting the positional relationship between the apparatus body S and the cornea C in the XY directions. An alignment detection optical system 90 is provided.

The anterior ocular segment observation optical system 10 includes a left and right
Anterior segment illumination light sources that directly illuminate the anterior segment located at
11a, 11b, and blowing air to the eye E
Airflow blowing nozzle 12 for attaching
13, chamber window glass 14, and half mirror 1
5, an objective lens 16, half mirrors 17 and 18,
Composed of a charge-coupled device (CCD) camera 19
And these are the optical axes O ₁Is placed on top.

When measuring the intraocular pressure of the eye E, FIG.
The air in the cylinder 12b is compressed by the piston 12a shown in (1), and the air is blown to the cornea C of the eye E through the airflow blowing nozzle 12. The piston 12a is driven by an airflow blowing unit (not shown), and the airflow blowing unit is driven based on outputs of an XY alignment light amount detection circuit 94 and a Z alignment detection correction circuit 74 described later.

The anterior segment image of the eye E illuminated by the anterior segment illumination light sources 11a and 11b
2, pass through the anterior segment window glass 13, the chamber window glass 14, and the half mirror 15, and are converged by the objective lens 16 while the half mirrors 17, 18
And is formed on the CCD camera 19.

The XY alignment index projection optical system 20
An XY alignment light source 21 that emits infrared light, a condenser lens 22, an aperture stop 23, a pinhole plate 24,
A dichroic mirror 25 and a projection lens 26 arranged on the optical path so that the focal point coincides with the pinhole plate 24.
, A half mirror 15, a chamber window glass 14,
It is constituted by an airflow blowing nozzle 12.

The infrared light emitted from the XY alignment light source 21 passes through the aperture stop 23 while being focused by the condenser lens 22, and is guided to the pinhole plate 24. The luminous flux passing through the pinhole plate 24 is applied to the dichroic mirror 2
5, is reflected by the projection lens 26, becomes a parallel light beam, is reflected by the half mirror 15, passes through the chamber window glass 14, passes through the inside of the airflow blowing nozzle 12, and as shown in FIG. Form K. In FIG. 5, the XY alignment index light K is
The light is reflected by the corneal surface T so as to form a bright spot image R at an intermediate position between the vertex P of the cornea C and the center of curvature of the cornea C. The aperture stop 23 is provided at a position conjugate with the vertex P of the cornea C with respect to the projection lens 26, and the XY alignment index light K is also used as corneal deformation detection light as described later.

The fixation target projection optical system 30 includes a fixation target light source 31 that emits visible light, a pinhole plate 32, a dichroic mirror 25, a projection lens 26, a half mirror 15, and a chamber window glass 14. And an airflow blowing nozzle 12.

The fixation target light emitted from the fixation target light source 31 passes through a pinhole plate 32 and a dichroic mirror 25, becomes a parallel light beam by a projection lens 26, is reflected by a half mirror 15, and is then reflected by a chamber window glass. 14, passes through the airflow spray nozzle 12 and passes through the eye E
It is led to. When the subject gazes at the fixation target as a fixation target, the line of sight of the subject (that is, the eye E) is fixed.

First XY alignment detecting optical system 40
Is an airflow spray nozzle 12 and a chamber window glass 1
4, a half mirror 15, an objective lens 16, half mirrors 17, 18, 91, and a position detection sensor 41 for detecting the position of the center of gravity of the bright spot image R'1 by a known method.
And an XY alignment position detection circuit 42. Further, the second XY alignment detecting optical system 90
Is an airflow spray nozzle 12 and a chamber window glass 1
4, a half mirror 15, an objective lens 16, half mirrors 17, 18, 91, an XY alignment detection stop 92, a light amount detection sensor 93, and an XY alignment light amount detection circuit 94.

The luminous flux projected onto the cornea C by the XY alignment optotype projection optical system 20 and reflected by the corneal surface T is:
It passes through the interior of the airflow spray nozzle 12, passes through the chamber window glass 14 and the half mirror 15, is partially converged by the objective lens 16, passes through the half mirror 17, and is further reflected by the half mirror 18. Is done.

A part of the light beam reflected by the half mirror 18 is transmitted through the half mirror 91 and
A bright spot image R'1 is formed on the light emitting element 1. The XY alignment position detection circuit 42 calculates the positional relationship between the apparatus body S and the cornea C in the XY directions based on the output of the position detection sensor 41, and outputs the calculation result to the Z alignment detection correction circuit 74 and the control circuit 80. .

The control circuit 80 outputs a drive control signal to the motors 104 and 108 based on the calculation result. That is, the first XY alignment detection optical system 40 can be used for automatic alignment by the alignment drive mechanism. On the other hand, since the first XY alignment detecting optical system 40 detects the position of the center of gravity of the incident light beam by the position detecting sensor 41, if disturbance light enters, the detection result includes an error. Therefore, in such a case, there is a disadvantage that the alignment in the XY directions cannot be accurately detected.

The light beam reflected by the half mirror 91 is X
A bright spot image R′3 is formed on the light amount detection sensor 93 after passing through the Y alignment detection stop 92. The XY alignment detection stop 92 is provided at a position conjugate to the virtual image R generated on the cornea C by the XY alignment target projection optical system 20 and the objective lens 16. The size of the XY alignment detection stop 92 is such that when the amount of deviation between the vertex of the cornea C and the optical axis O ₁ is reduced to a level that does not affect the accuracy of the intraocular pressure measurement, the amount of light exceeding a predetermined amount is reduced. Light amount detection sensor 9
3 so as to be incident. The XY alignment light amount detection circuit 94 determines whether or not alignment in the XY directions has been completed based on the output of the light amount detection sensor 93, and outputs the determination result to the control circuit 80.

That is, the ideal position of the apparatus main body S when there is no deviation between the vertex of the cornea C and the optical axis O ₁ is referred to as “alignment completion position”, and the deviation is within an allowable range. Assuming that the positional reference to be satisfied is a “predetermined position reference”, it can be said that this predetermined position reference is defined by the alignment completion position, and the second XY alignment detection optical system 90 satisfies the predetermined position reference. It can be said that it is to judge whether or not the light amount of the corneal reflected light beam at the time of satisfying the predetermined light amount standard (here, the “predetermined light amount standard” distinguishes the corneal reflected light beam from the disturbance light, etc. Is determined based on at least the amount of light that the corneal reflected light beam should have.)

This second XY alignment detecting optical system 9
The value 0 indicates that the amount of incident light is only detected by the light amount detection sensor 93, so that the amount of misalignment in the XY directions cannot be detected, and whether or not the alignment in the XY directions has been completed is detected in a binary manner. Stop at. However, X
Since the influence of disturbance light can be removed by the action of the Y-alignment detection stop 92, the XY-direction alignment is completed by the combination of the second XY-alignment detection optical system 90 and the first XY-alignment detection optical system 40. Can be accurately determined.

Although the first XY alignment detection optical system 40 determines that the alignment state of the apparatus main body S satisfies a predetermined position criterion, the second XY alignment detection optical system 90 determines a predetermined position. If it is not determined that the light amount criterion is satisfied, the control circuit 80 displays on the screen G of the monitor 81 that automatic alignment is impossible, and stops the apparatus main body S that has been stopped at that time. The orbit is moved around a position within a predetermined area in the XY plane. The predetermined area is, for example, ± 1 m in the X direction around the stop position.
What is necessary is just to define ± 1 mm in the m and Y directions, or to define a radius of 1 mm centered on the stop position.

On the other hand, the cornea C transmitted through the half mirror 18
Is reflected on the CCD camera 19 by a bright spot image R'2.
To form The CCD camera 19 outputs an image signal to the monitor 81 via the control circuit 80. As a result, FIG.
As shown in FIG. 7, an anterior segment image E ′ of the subject's eye E and a luminescent spot image R ′ 2 of the XY alignment index light are displayed on the screen G of the monitor 81. Note that the alignment assist mark H displayed on the screen G is generated by an image generating device (not shown).

The luminous flux reflected from the cornea C reflected by the half mirror 17 is transmitted to the corneal deformation detecting optical system 5.
The light is guided to 0, passes through the pinhole plate 51, and enters the deformation detection sensor 52. As the deformation amount detection sensor 52, a light receiving sensor capable of detecting the amount of light, such as a photodiode, is used.

The output of the deformation amount detection sensor 52 is input to a light amount change detection circuit 53, which detects a temporal change in the amount of received light in the deformation amount detection sensor 52. The detection result of the light amount change detection circuit 53 is output to the control circuit 80, and the control circuit 80 calculates the intraocular pressure value of the eye E based on the detection result and the pressure change curve of the cylinder 12b.

The Z-alignment index projection optical system 60 has a Z-alignment light source 61 for emitting infrared light, a condenser lens 62, an aperture stop 63, a pinhole plate 64, and focuses on the pinhole plate 64. It is constituted by a projection lens 65 arranged on an optical path so as to be, which are arranged on the optical axis O _2.

The infrared light emitted from the Z alignment light source 61 is condensed by a condenser lens 62 while being condensed by an aperture stop 6.
3 and is guided to the pinhole plate 64. The light beam passing through the pinhole plate 64 is converted into a parallel light beam by the projection lens 65 and guided to the cornea C, and is reflected on the corneal surface T so as to form a bright spot image Q as shown in FIG. Note that the aperture stop 63 is provided at a position conjugate with the vertex P of the cornea C with respect to the projection lens 65.

The Z alignment detecting optical system 70 is composed of an imaging lens 71, a cylindrical lens 72 having a refractive power in the Y direction, a detecting sensor 73, and a Z alignment detecting and correcting circuit 74. ₃ are arranged on.

The luminous flux of the Z alignment index light projected from the corneal surface T projected by the Z alignment index projection optical system 60 is converged by the imaging lens 71 and is transmitted through the cylindrical lens 72 to the detection sensor 73 on the detection sensor 73. Q ′ is formed. The detection sensor 73 is a light receiving sensor capable of detecting a position, such as a line sensor or a PSD.
The output of the detection sensor 73 is a Z alignment detection correction circuit 7
4 is output.

In the plane (X) including the optical axis O ₃ and the X axis,
In the Z plane), the bright spot image Q and the detection sensor 73 have a conjugate positional relationship with respect to the imaging lens 71, and the optical axis O
_In a plane including ₃ and the Y axis, the corneal vertex P and the detection sensor 73 have a conjugate positional relationship with respect to the imaging lens 71 and the cylindrical lens 72. That is, since the detection sensor 73 is in a conjugate relationship with the aperture stop 63 (the magnification at this time is selected so that the image of the aperture stop 63 is smaller than the size of the detection sensor 73), the cornea C in the Y direction. Is reflected, the reflected light flux on the corneal surface T efficiently enters the detection sensor 73. Further, when projecting the slit light long in the Y direction onto the cornea C, even if the cornea C is displaced in the Y direction as described above, the overall incident efficiency is reduced, but the reflected light flux is efficiently transmitted to the detection sensor 73. Can be incident.

Further, here, in order to accurately detect the alignment in the Z direction without being affected by the deviation of the alignment in the XY directions, the XY alignment position detecting circuit 4 is used.
2 (XY direction alignment information) is input to a Z alignment detection correction circuit 74 to correct the Z alignment information obtained by the detection sensor 73.

FIGS. 8A and 8B are diagrams for explaining the relationship between the incidence and reflection of the alignment index light when the position of the cornea C of the eye E is displaced. FIG. 8A shows the position of the cornea C in the Z direction. (B) shows a case where the position of the cornea C is shifted in the X direction.

As shown in FIG. 8A, when the position of the cornea C is shifted by ΔZ in the Z direction, the position of the bright spot image Q ′ on the detection sensor 73 becomes ΔQ _Z × m (ΔQ _Z = ΔZsi
nθ). Here, θ is the optical axis O ₁
And the angle of the optical axis O _2, or is an angle of the optical axis O ₁ and the optical axis O _3, m is the magnification of the Z alignment detection optical system 70. Therefore, when the position of the cornea C matches in the XY directions and only shifts in the Z direction, the shift amount (movement amount) ΔQ ′ of the bright spot image Q ′ on the detection sensor 73 from the reference position. Is obtained, the displacement amount ΔZ of the position of the cornea C can be easily calculated by ΔZ = ΔQ ′ / (sin θ × m).

However, as shown in FIG.
Is shifted by ΔX in the X direction, the position of the bright spot image Q ′ on the detection sensor 73 is ΔQ _X × m (ΔQ _X =
ΔXcos θ). Therefore, when the position of the cornea C is shifted in the Z direction and the X direction, the bright spot image Q on the sensor 73 'positions of _{ΔQ' = ΔQ Z × m +} ΔQ X × m = (ΔZ × sinθ × m) + (ΔX × cos θ × m)

Therefore, in this case, the Z alignment detection correction circuit 74 determines whether the movement amount ΔQ ′ of the bright spot image Q ′ on the detection sensor 73 and the XY alignment position detection circuit 4
2 based on the deviation amount ΔX output from the
And the positional relationship of the cornea C in the Z direction (shift amount ΔZ) according to the following equation (1), and the shift amount Δ
Z is output to the control circuit 80.

ΔZ = (ΔQ′−ΔXcos θ × m) / (sin θ × m) (1) The control circuit 80 determines the motor 112 based on the calculation result.
To output a drive control signal.

Next, the operation of the embodiment of the present invention will be described for the case where the auto mode is selected.

When measuring a healthy eye, the examiner observes the anterior eye image E ′ on the screen G of the monitor 81 shown in FIG. Operate the control lever 102 so that it is positioned
01 is moved. When the reflected light of the cornea C enters the position detection sensor 41 and the detection sensor 73, the XY alignment position detection circuit 42 and the Z alignment detection correction circuit 74
Output the XY alignment information and the Z alignment information to the control circuit 80.

The control circuit 80 controls the motor 1 based on the output XY alignment information and Z alignment information.
Control signals are output to 04, 108 and 112. Accordingly, in order to move the bright spot image R′1 to a desired position on the position detection sensor 41, that is, on the screen G of the monitor 81, the bright spot image R′2 is positioned within the range of the alignment auxiliary mark H and the focus is adjusted. Automatic alignment is performed while moving the case 115 in the XY direction and the Z direction in order to move it to a suitable position.

When the vertex of the cornea C substantially coincides with the optical axis O ₁ ,
Since a predetermined amount or more of light enters the light amount detection sensor 93,
An XY alignment light amount detection circuit 94 outputs an alignment completion signal to the control circuit 80. The control circuit 80
When an alignment completion signal in the XY direction is received from the XY alignment light amount detection circuit 94 and an alignment completion signal in the Z direction is received from the Z alignment detection and correction circuit 74, an airflow blowing unit (not shown) is operated to blow airflow. Air is blown from the nozzle 12 toward the cornea C, and the amount of deformation of the cornea C when the air is blown is detected by the corneal deformation amount detection optical system 50. Thereafter, the intraocular pressure value of the eye E is calculated from the air blowing pressure when the predetermined deformation amount is obtained, using a known method.

The XY alignment position detection circuit 42
Alignment between the apparatus body S and the subject's eye E is detected based on the XY alignment information output from the device and the Z alignment information output from the Z alignment detection and correction circuit 74, and the detection result is displayed on the monitor 81. Is also good.

On the other hand, when measuring an eye to be inspected which is not in a good state such as a diseased eye, as shown in FIG.
At 1, a small amount of corneal scattered light Δr caused by corneal surface roughness or the like due to corneal surgery is incident in addition to the bright spot image R ′ 1 from the cornea C of the eye E to be examined. For this reason, the XY alignment information output from the XY alignment position detection circuit 42 includes an error based on the corneal scattered light Δr.

That is, when there is such corneal scattered light Δr, the position detection sensor 41 detects the entire center of gravity position W obtained by combining the bright spot image R′1 and the corneal scattered light Δr. X
The Y alignment position detection circuit 42 uses the bright spot image R′1
The amount of deviation between the vertex of the cornea C of the eye E and the optical axis O ₁ is calculated based on the position W of the center of gravity of the corneal scattered light Δr and the calculation result is output to the control circuit 80.

Therefore, as shown in the figure, even when the bright spot image R'1 is not within the alignment area H 'corresponding to the alignment auxiliary mark H, the bright spot image R'1 and the corneal scattering When the position W of the center of gravity with the light Δr enters the alignment area H ′ and substantially coincides with the optical axis, X
The Y alignment position detection circuit 42 erroneously recognizes that the alignment in the XY directions has been completed at the coincident position.

However, in this case, a part or all of the bright spot image R'3 is blocked by the XY alignment detection stop 92, so that a sufficient amount of light does not enter the light amount detection sensor 93 and the XY alignment light amount is detected. The circuit 94 determines that the XY alignment has not been completed because the light amount detected by the light amount detection sensor 93 is insufficient. Although the XY alignment position detection circuit 42 outputs the calculation result indicating that the XY alignment is completed, the XY alignment light amount detection circuit 94 outputs the determination result indicating that the predetermined amount or more of light is not incident. If you have
The control circuit 80 displays on the screen G of the monitor 81 that automatic alignment is impossible, and controls the motors 104 and 108 so that the apparatus main body S orbits in a predetermined area in the XY plane centering on the position at that time. Drive.

When the light amount exceeding the predetermined amount enters the light amount detection sensor 93 while the apparatus body S is moving around the predetermined area, the XY alignment light amount detection circuit 94 determines that the alignment is completed at that time. And the control circuit 8
Send an alignment complete signal to 0. In this case, Z alignment information that is not corrected by the output of the XY alignment position detection circuit 42 (directly obtained by the detection sensor 73) is output from the Z alignment detection correction circuit 74 to the control circuit 80. The control circuit 80
When an alignment completion signal is received from both the Y-alignment light amount detection circuit 94 and the Z-alignment detection correction circuit 74, an airflow blowing unit (not shown) is activated to start measuring the intraocular pressure as described above.

On the other hand, the control circuit 80 stores the output address of the XY alignment position detection circuit 42 when the alignment completion signal is received from the XY alignment light quantity detection circuit 94 in a memory (not shown), and stores it in the next measurement. The apparatus main body S is moved to a position corresponding to the stored output address (the stored position is set as a unique alignment completion position for the subject's eye, and a position reference defined by the new alignment completion position is used as the apparatus main body S Control). Normally, when measuring intraocular pressure for a certain eye, a plurality of measurements are made. By changing the center address of the XY alignment position detection circuit 42 in accordance with the eye to be inspected, the XY alignment is measured from the next measurement. The apparatus main body S can be directly moved to a position where the light quantity detection circuit 94 outputs an alignment completion signal. When the eye to be examined has changed (when the left and right eyes have changed, when the subject has changed), or when a clear switch or a print switch (not shown) is operated, the control circuit 80 sets the changed XY alignment position detection circuit. The center address of 42 is reset.

When the predetermined amount of light does not enter the light amount detection sensor 93 even when the apparatus main body S is moved within the predetermined area and scanned as described above, the control circuit 80 controls the monitor 81 or the audio output unit 82. The examiner is notified to that effect through (see FIG. 4). In such a case, the examiner switches the mode from the auto mode to the manual mode by using a mode switch not shown, and
Alignment is manually performed by operating the control lever 102 while checking. In this manual mode,
If you rely on the examiner's vision and the alignment result is not affected by unnecessary reflected light, etc., and it is obvious from the beginning that the eye to be inspected is in a bad state and automatic alignment is difficult, this manual mode should be used from the beginning. By making a selection, the efficiency of the alignment operation can be increased.

When the examiner presses the manual switch 103 after the completion of this alignment, the airflow blowing unit operates to start the measurement of the intraocular pressure. The control circuit 80 stores the output address of the XY alignment position detection circuit 42 when the manual switch 103 is pressed in a memory (not shown),
The center address of the Y alignment position detection circuit 42 is replaced with the output address.

In the second and subsequent measurements after the measurement in the manual mode as described above, when the examiner selects the auto mode again by the mode changeover switch, the control circuit 80 controls the alignment completion position (XY alignment) stored in the memory. The apparatus main body S is moved to the replaced center address of the position detection circuit 42), and when the automatic alignment is completed, the measurement of the intraocular pressure is started. Thus, the automatic alignment can be performed in the second and subsequent measurements even for an eye to be inspected for which automatic alignment is originally difficult, and the measurement can be automatically started.

The ophthalmologic apparatus according to the present invention is not limited to the above-mentioned tonometry apparatus, but may be any apparatus that requires alignment such as a corneal endothelium photographing apparatus or a slit lamp. When the ID number of the patient (subject) is input to the ophthalmologic apparatus during measurement or the like, or when an ID card is set, an appropriate alignment completion position of each patient is stored in association with the ID. By doing so, when diagnosing the same patient on another day, the apparatus main body can be automatically moved to an appropriate position according to the eye to be examined.

[0064]

Since the ophthalmologic apparatus according to the present invention is configured as described above, even if the condition of the eye to be examined is not good, it is possible to effectively utilize the automatic alignment function to perform alignment. The efficiency of the alignment work and the burden on the subject can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view showing a configuration of an alignment driving mechanism of an intraocular pressure measuring device according to an embodiment of the present invention.

FIG. 2 is a plan view illustrating a configuration of an alignment driving mechanism in FIG. 1;

FIG. 3 is a side view schematically showing an optical system of an apparatus main body of the tonometry apparatus shown in FIGS. 1 and 2;

FIG. 4 is a plan view showing the optical system of FIG. 3;

FIG. 5 is an explanatory diagram showing the reflection of alignment target light projected from the front onto the cornea of the subject's eye.

FIG. 6 is an explanatory diagram showing an anterior eye image of a healthy eye displayed on a monitor screen of the tonometry apparatus.

FIG. 7 is an explanatory diagram showing reflection of alignment index light projected from a diagonal direction onto a cornea of an eye to be examined.

FIG. 8 shows the relationship between the incidence and reflection of alignment index light when the position of the cornea of the eye to be examined is shifted within the XZ plane;
(A) is an explanatory diagram in the case of displacement in the Z direction, and (b) is an explanatory diagram of a displacement in the X direction.

FIG. 9 is an explanatory diagram showing a light receiving state of a position detection sensor when an eye to be examined having a rough cornea is measured.

[Explanation of symbols]

Reference Signs List 10 anterior eye observation optical system 20 XY alignment index projection optical system 30 fixation target projection optical system 40 first XY alignment detection optical system 41 position detection sensor 42 XY alignment position detection circuit 50 corneal deformation amount detection optical system 60 Z alignment Index projection optical system 70 Z alignment detection optical system 74 Z alignment detection correction circuit 80 control circuit 81 monitor 90 second XY alignment detection optical system 92 XY alignment detection stop 93 light intensity detection sensor 94 XY alignment light intensity detection circuit C cornea E eye to be examined K XY alignment index light (alignment index light) S main unit

Claims (6)

[Claims] 1. An ophthalmic apparatus which requires alignment of a device body with respect to an eye to be inspected, an alignment index projection system for projecting alignment index light toward a cornea of the eye to be inspected, and movement control of the device body. Movement control means, first detection means for detecting the alignment state of the apparatus body by causing the corneal reflection light beam of the alignment index light to enter a position detection element capable of detecting the center of gravity of the incident light beam, and the first detection The alignment state detected by the means is
First determining means for determining whether or not a predetermined position criterion defined based on the alignment completion position of the apparatus main body is satisfied; and causing the corneal reflected light beam to enter a light amount detecting element capable of detecting a light amount of an incident light beam. Second detecting means for detecting an alignment state of the apparatus main body, and second determining means for determining whether or not the alignment state detected by the second detecting means satisfies a predetermined light amount standard. The control means, when it is determined by the first determination means that the alignment state does not satisfy the position reference, moves the apparatus body based on the detection result of the first detection means, the alignment state is When the first determination unit and the second determination unit determine that the position criterion is satisfied but the light amount criterion is not satisfied, Ophthalmologic apparatus characterized by moving in a predetermined area. 2. If the movement control means determines that the alignment state satisfies the light amount standard while moving the apparatus main body within the predetermined area, measurement or photographing by the apparatus main body is automatically performed. The ophthalmic apparatus according to claim 1, wherein the ophthalmologic apparatus is started in a dynamic manner. 3. When the measurement or photographing by the apparatus body is automatically started, the position of the apparatus body when the measurement or photographing is performed is stored as the alignment completion position, The ophthalmologic apparatus according to claim 2, wherein the position reference is newly defined based on the stored alignment completion position. 4. The apparatus main body is manually moved when it is not determined that the alignment state satisfies the light quantity standard even though the movement control means moves the apparatus main body within the predetermined area. When alignment or alignment is completed and measurement or imaging by the apparatus main body is started, the position of the apparatus main body when the measurement or imaging is being performed is stored as the alignment completion position. 2. The ophthalmologic apparatus according to claim 1, wherein the position reference is newly defined based on the stored alignment completion position. 5. An ophthalmologic apparatus which needs to align an apparatus main body with an eye to be inspected, an alignment index projection system for projecting alignment index light toward a cornea of the eye to be inspected, and movement control of the apparatus main body. Movement control means, first detection means for detecting the alignment state of the apparatus body by causing the corneal reflection light beam of the alignment index light to enter a position detection element capable of detecting the center of gravity of the incident light beam, and the first detection The alignment state detected by the means is
And first determining means for determining whether or not a predetermined position criterion defined based on the alignment completion position of the apparatus body is satisfied.The apparatus body is manually moved to perform alignment,
When the alignment or measurement is started by the apparatus main body after the alignment is completed, the position of the apparatus main body when the measurement or imaging is being performed is stored as the alignment completed position, and the stored alignment is stored. The position reference is newly defined based on the completion position, and the movement control unit determines that the alignment state satisfies the newly defined position reference at the time of the next measurement or imaging by the device main body. An ophthalmologic apparatus, wherein the alignment is performed by moving the apparatus body as determined by the first determining means. 6. The apparatus according to claim 1, wherein said alignment completion position is stored in association with an individual ID of a subject, and said movement control means performs alignment by moving said apparatus main body in accordance with said ID. Item 6. An ophthalmologic apparatus according to item 5.