JP2001353126A - Ophthalmologic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ophthalmologic apparatus capable of improving operability for both of a beginner and an expert. SOLUTION: A stand which is attachable and detachable to and from the eye to be examined is internally provided with an anterior segment observation optical system for observing the anterior segment of the eye to be examined. The stand is provided with a lens holding unit and a motor unit for changing the focal position of the anterior segment observation optical system. The position of the stand relative to the eye to be examined is detected by a microswitch 8 and a motor 101 of the motor unit is controlled by a control circuit 80 in order to change the focal position in accordance with the output from the microswitch 8. The operation to change the focal position by driving of the motor 101 is prohibited by a changeover switch 6a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ophthalmologic apparatus in which an eye to be inspected and a main body of the apparatus need to be aligned in a predetermined positional relationship.

[0002]

2. Description of the Related Art An ophthalmologic apparatus is provided with an anterior eye observation optical system for observing an anterior eye of an eye to be inspected, and an anterior eye of the eye to be inspected can be observed by an observation means such as a monitor or an eyepiece. Things are known.

[0003] While observing the anterior ocular segment, the gantry including the optical system is moved in a three-dimensional direction to adjust the alignment with the eye to be examined. By the way, in the case of such an alignment adjustment, the measurement head at the tip of the gantry should not be too close to the eye to be examined, and the gantry should be at a position slightly apart from an appropriate working distance at the start of alignment. Is generally moved, and the gantry is gradually moved toward the subject's eye from this position to start positioning to a proper working distance.

However, when performing such an operation,
At the start of the alignment adjustment, the eye to be examined is out of focus, so that it is difficult for a person unfamiliar with the operation to know in which direction the measuring head can be moved.

Therefore, as disclosed in Japanese Patent Application Laid-Open No. 2-283352, the position of the gantry is detected, and the focusing lens of the anterior ocular segment observation optical system is controlled based on the detection result. There has been proposed one that can change the distance (movable focus). That is,
When the eye to be inspected and the gantry are separated from each other, the position of the focusing lens is controlled so that the anterior ocular segment observation optical system is focused on the eye to be inspected in the separated state. When approaching the positional relationship close to the proper working distance, the position of the focusing lens is controlled so that the focus position is near the proper working distance. This makes it possible to relatively easily perform the alignment even if the user is not an expert.

[0006]

However, the one disclosed in Japanese Patent Application Laid-Open No. 2-283352 is easy to operate for beginners who are unfamiliar with the operation, but it is difficult for a skilled person to complete the alignment. It took time.

That is, an examiner skilled in operation can quickly bring the measurement head to an appropriate working distance even if the anterior ocular segment observation optical system has a fixed focus. However, when the focal position is switched as in Japanese Patent Application Laid-Open No. 2-283352, the criterion for determination is changed, and conversely, it takes time and takes time. Even if it does not get confused, it is necessary to wait until the movement of the focusing lens is completed. On the contrary, it takes time to complete the alignment. Also, one eye, for example,
After the measurement of the left eye, to perform the measurement of the right eye, it is necessary to move the gantry to the right, but in this case, to prevent the device from hitting the nose of the subject, It is necessary to perform an operation of retracting the gantry rearward beyond the height of the nose and then moving the gantry to the right.

[0008] When such a retreat operation is performed, Japanese Patent Laid-Open No.
In the article of JP 83352,. Since the focusing lens moves to a position corresponding to the retracted position, control is performed such that the focusing lens returns to the original position. Since the examiner must restart the operation after the completion of the movement of the lens, there is a disadvantage that it takes a longer time to complete the alignment in the case of the fixed focus.

An object of the present invention is to provide an ophthalmologic apparatus which is easy to use for both beginners and skilled persons and which can improve operability.

[0010]

In order to achieve the object, an ophthalmologic apparatus according to claim 1 is provided for observing a gantry which can approach and separate from an eye to be examined and an anterior eye part of the eye to be examined. An anterior eye observation optical system provided in a gantry, a focus position changing unit for changing a focus position of the anterior eye observation optical system, and a position for detecting a position of the gantry with respect to an eye direction to be inspected. Gantry position detecting means, a focus position changing control means for controlling the focus position changing means based on an output from the gantry position detecting means, and a prohibiting means for prohibiting the operation of the focus position changing means. The gist is that the device is an ophthalmic device.

According to the ophthalmologic apparatus of the first aspect, it is possible to switch between the case where the control of the focusing position changing means is permitted and the case where the control of the focus position changing means is prohibited by the prohibiting means.

According to a second aspect of the present invention, in the ophthalmologic apparatus, the prohibiting means operates to correct a shift of the focus position changing means due to vibration of the apparatus main body.

[0013]

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

Referring to FIG. 11, an ophthalmologic apparatus S includes a base 2 having a receiving table 1 for supporting a subject's head, and a lower mount 3 disposed above the base 2 and movable in the left-right and front-rear directions. When,
An upper gantry 4 is provided which can be displaced in the up, down, left, right, front and rear directions with respect to the lower gantry 3.

A joystick 5 having a manual photographing switch 5a and a group of various operation switches 6 are provided on the upper surface of the lower gantry 3 on the examiner side. Also, on the lower frame 3,
A monitor 3a is provided.

On the front surface of the upper gantry 4, there is provided a nozzle portion 7 facing the eye E to be examined. As shown in FIGS. 1 and 2, an anterior eye observation optical system 10 for observing the anterior eye of the eye E is provided in the upper gantry 4 for detecting alignment in the XY directions and detecting corneal deformation. An XY alignment target projection optical system 20 that projects the index light onto the cornea C of the eye E from the front, a fixation target projection optical system 30 that presents a fixation target to the eye E, and a reflected light flux of the XY alignment index light by the cornea C. XY alignment detecting optical system 40 for detecting the positional relationship between the ophthalmic apparatus S and the cornea C in the XY directions by receiving
A corneal deformation detection optical system 50 that receives the reflected light of the alignment index light from the cornea C and detects the amount of deformation of the cornea C. A Z alignment index that projects an alignment index light in the Z direction (focusing direction) obliquely onto the cornea C. The projection optical system 60 receives the reflected light flux of the Z alignment index light from the cornea C from a direction symmetric with respect to the optical axis of the anterior ocular segment observation optical system 10 and detects the positional relationship between the ophthalmologic apparatus S and the cornea C in the Z direction. An apparatus optical system such as a Z alignment detection optical system 70 is provided.

The lower base 3 is moved in the up-down, left-right, and front-rear directions during manual alignment by rotating the joystick 5 (for moving up and down), tilting left and right (for moving left and right), and tilting back and forth (for moving back and forth). The movement of the upper gantry 4 in the up, down, left, right, front and rear directions is to be performed at the time of automatic alignment. However, only one of the gantry 3 and 4 can be moved, and all the operations are performed by manual alignment (this embodiment). It is good also as composition. In the case of a manual alignment type device, the upper and lower mounts 3 and 4 may be one housing-like mount.

The movement of the gantry 3 or 4 is detected by the microswitch 8 shown in FIG.

That is, when the lower gantry 3 moves before a certain position, the microswitch 8 is turned on by the convex portion 2a of the base 2, whereby the position of the lower gantry 3 in the front-back direction is detected. This detection result is transmitted to the objective lens 1 described later.
6 is used for control.

The anterior segment observation optical system 10 includes a plurality of anterior segment illumination light sources 11, which are located on the left and right sides of the eye E and directly illuminates the anterior segment, an airflow blowing nozzle 12, and an anterior segment window glass 13. , Chamber window glass 14, half mirror 1
5. Objective lens 16, half mirrors 17, 18, CCD
It has a camera 19 and O1 is its optical axis.

The anterior segment image of the eye E illuminated by the anterior segment illumination light source 11 passes through the inside and outside of the airflow blowing nozzle 12 and passes through the anterior segment window glass 13, the chamber window glass 14,
The light is transmitted through the half mirror 15, is transmitted through the half mirrors 17 and 18 while being focused by the objective lens 16, and is formed on the CCD camera 19. The nozzle unit 7 may be the same as the airflow blowing nozzle 12, may be a nozzle communicating with the airflow blowing nozzle 12, or may be a cover that covers the airflow blowing nozzle 12.

As shown in FIG. 7A, the objective lens 16 is held by a lens holding unit 90 and the objective lens 1 is driven by a motor 101 of a motor unit 100.
6 is moved between two positions along the optical axis O1. The lens holding unit 90 and the motor 101 constitute a focus position changing unit, and the motor 101 is driven according to a mode selection operation on an operation unit (not shown) of the apparatus main body.

The lens holding unit 90 has a base 91 fixed to the gantry 3 and having a holding cylinder 91a coaxial with the optical axis O1, and a lens cell 92 movable within the holding cylinder 91a along the optical axis O1. And an annular pressing member 93 for holding the objective lens 16 in cooperation with the lens cell 92. A long hole 91b extending in the axial direction is formed in the holding cylinder portion 91a, and a pin 92a protruding from the lens cell 92 faces the long hole 91b.

When the eye E and the gantry 3 are separated from each other, the pin 92a has an elongated hole 91 as shown in FIG.
b is in contact with the end on the side of the CCD camera 19. When the eye E and the gantry 3 are close to each other, FIG.
As shown in (5), the long hole 91b is in contact with the end on the nozzle 12 side.

The motor unit 100 is shown in FIG.
As shown in (B), a motor 101 that can rotate forward and reverse and a bracket 102 fixed to an output shaft 101a of the motor 101 are provided.
And the output shaft 101 located on one side of the bracket 102.
a, a push washer 104 for holding the annular base 103a of the arm member 103 together with one surface side of the bracket 102, a clutch member 105 such as a plurality of leaf springs, and a tip screw of the output shaft 101a. And a nut 106 for screwing the push washer 104 toward the base portion 103a by screwing with the portion.

At the tip of the arm member 103, an arm member 1 is provided.
A concave portion 103b is provided extending along the extension direction of the pin 03, and a pin 92a is displaceably engaged with the concave portion 103b.

When the motor 101 is driven, the output shaft 101
Simultaneously with the rotation of the bracket 102a, the arm member 103 rotates integrally with the urging force of the clutch member 105.

The rotation of the arm member 103 is controlled by the
3b, the pin 92a is displaced in the extending direction and the pin 92a is inserted into the elongated hole 91b.
And the objective lens 16 is moved. When the pin 92a comes into contact with the end of the elongated hole 91b (FIGS. 9A and 9B), further displacement is stopped, and the objective lens 16 is positioned at an appropriate position. Slip against bias (idle)
I do.

At this time, the motor 101 is stopped after a predetermined period of time or when the drive is stopped by detecting a load caused by slipping of the clutch member 105, so that seizure is prevented and the objective lens 16 is reliably positioned. it can.

The XY alignment target projection optical system 20 includes:
A 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 that is 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, and 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 light beam that has passed through the pinhole plate 24 is reflected by the dichroic mirror 25, becomes a parallel light beam by the projection lens 26, is reflected by the half mirror 15, passes through the chamber window glass 14, and passes through the airflow blowing nozzle 12.
XY alignment index light K is formed as shown in FIG. In FIG. 3, the XY alignment index light K 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 corneal vertex P with respect to the projection lens 26.

The fixation target 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, a chamber window glass 14, and an airflow blowing nozzle 12. Have.

The fixation target light emitted from the fixation target light source 31 passes through a pinhole plate 32 and a dichroic mirror 25, and is converted into parallel light by a projection lens 26 to form a half mirror 1
After being reflected at 5, the light passes through the chamber window glass 14, passes through the airflow spray nozzle 12, and passes through the eye E to be examined.
It is led to. The subject's gaze is fixed by gazing at the fixation target as a fixation target.

The XY alignment detecting optical system 40 includes an airflow blowing nozzle 12, a chamber window glass 14, a half mirror 15, an objective lens 16, and half mirrors 17 and 1.
8, a sensor 41, and an XY alignment detection circuit 42.

The luminous flux projected onto the cornea C by the XY alignment index projection optical system 20 and reflected by the corneal surface T passes through the inside of the nozzle 12 and the chamber window glass 14,
The light passes through the half mirror 15, is partially focused by the half mirror 17 while being focused by the objective lens 16, and is partially reflected by the half mirror 18.

The light beam reflected by the half mirror 18 forms a bright spot image R ′ 1 on the sensor 41. Sensor 41 is P
It is a light receiving sensor capable of detecting a position like an SD. The XY alignment detection circuit 42 calculates the positional relationship (XY directions) between the ophthalmologic apparatus S and the cornea C based on the output of the sensor 41 by known means, and calculates the calculation result as a Z alignment detection correction circuit 74 and a control circuit. Output to 80.

On the other hand, the cornea C transmitted through the half mirror 18
The reflected luminous flux from the image 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 3a, and as shown in FIG. 4, an anterior segment image E 'of the eye E to be inspected and a bright spot image R'2 of the XY alignment index light are displayed on the monitor 3a. Note that H is an alignment assist mark generated by an image generating unit (not shown).

Further, a part of the light beam reflected by the half mirror 17 is guided to a corneal deformation detecting optical system 50,
The light passes through the pinhole plate 51 and is guided to the sensor 52. The sensor 52 is a light receiving sensor capable of detecting the amount of light, such as a photodiode.

The Z-alignment index projection optical system 60 emits light so that the focal points coincide with the Z-alignment light source 61 that emits infrared light, the condenser lens 62, the aperture stop 63, the pinhole plate 64, and the pinhole plate 64. It has a projection lens 65 located on the road, O2 being its optical axis.

The infrared light emitted from the Z alignment light source 61 passes through the aperture stop 63 while being collected by the condenser lens 62 and is guided to the pinhole plate 64. Pinhole plate 6
The light beam passing through 4 is converted into parallel light by the projection lens 65, guided to the cornea C, and 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 has a corneal vertex P with respect to the projection lens 65.
Is provided at a position conjugate with

The Z alignment detection optical system 70 includes an imaging lens 71, a cylindrical lens 72 having power in the Y direction, a sensor 73, and a Z alignment detection correction circuit 74.
And O3 is the optical axis.

The reflected light flux of the target light projected by the Z alignment target projection optical system 60 on the corneal surface T is:
A bright spot image Q ′ is formed on the sensor 73 via the cylindrical lens 72 while being focused by the imaging lens 71. The sensor 73 is a light receiving sensor capable of detecting a position, such as a line sensor or a PSD. The information from the sensor 73 is Z
It is guided to the alignment detection correction circuit 74.

In the XZ plane, the bright spot image Q and the sensor 73 are in a conjugate positional relationship with respect to the imaging lens 71. In the YZ plane, the corneal vertex P and the sensor 73 are connected to the imaging lens 71 and the cylindrical lens. 72 has a conjugate positional relationship. That is, the sensor 73 is 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 sensor 73), and even if the cornea C is displaced in the Y direction, the reflected light flux on the corneal surface T has an efficiency of The light enters the sensor 73 well. Also, by projecting long slit light in the Y direction, the same effect can be obtained although the efficiency is reduced.

In the present embodiment, as shown in FIG. 1, the projection system and the light receiving system for detecting the alignment in the Z direction are the Z alignment index projection optical system 60 and the Z alignment detection optical system 70. , One for each. In such a configuration, XY alignment information from the XY alignment detection circuit 42 is input to the Z alignment detection correction circuit 74 in order to accurately perform alignment detection in the Z direction without being affected by misalignment in the XY directions. I have to.

That is, as shown in FIG. 6A, when the position of the cornea C is shifted by ΔZ in the Z direction, the position of the bright spot image Q ′ moves on the sensor 73 by ΔZ × sin θ × m. Here, θ is the angle between the axis O1 and the axis O2 and the axis O1 and the axis O3, and m is the imaging magnification of the Z alignment optical system 70.
If the cornea C is only displaced in the Z direction, the displacement amount of the cornea C can be easily calculated from the movement amount of the bright spot image Q ′ on the sensor 73.

However, as shown in FIG.
Is shifted by .DELTA.X in the X direction, the position of the bright spot image Q 'moves on the sensor 73 by .DELTA.X.times.cos.theta..times.m. Therefore, when there is a deviation in the Z direction and the X direction, the Z alignment detection correction circuit 74 calculates the deviation amount ΔQ ′ of the bright spot image Q ′ on the sensor 73 from the reference position and the deviation amount from the XY alignment detection circuit 42. From ΔX, Z of the ophthalmic apparatus S and the cornea C
The positional relationship in the direction (shift amount ΔZ) is calculated based on the following equation (1), and the calculation result is output to the control circuit 80.

ΔZ = (ΔQ′−ΔX × cos θ × m) / (sin θ × m) (1) Next, in such a configuration, an operation example in the case of an inspector unfamiliar with the alignment operation will be described. I do.

The examiner selects the alignment position change mode with the changeover switch 6a (see FIG. 12) provided in the switch group 6, and moves the gantry 3 to a safe position away from the eye E. At this time, the current position of the gantry 3 is detected by the microswitch 8.

When the microswitch 8 detects that the gantry 3 is separated from the eye E by a predetermined distance or more when the alignment position change mode is selected by the changeover switch 6a, as shown in FIG. The motor 101 of the motor unit 100 is driven by the control means 80, and the objective lens 1 is moved via the lens holding unit 90.
6 is displaced, and the pin 92a is
The displacement of the objective lens 16 is stopped at the position where it comes into contact with the end on the side of the D camera 19 (the position shown in FIGS. 7B and 9B).

In this state, approximate alignment is performed in the X and Y directions so that the anterior segment of the eye E is focused on the CCD camera 19. After the rough alignment is completed, the gantry 3 is further pushed out toward the subject, and the push-out is detected by the microswitch 8.

The control means 80 recognizes from the detection by the micro switch 8 that the working distance has approached the proper working distance, and operates the motor unit 100 again to cause the pin 92a to move the pin 92a of the elongated hole 91b to the nozzle 12 side. The objective lens 16 is displaced until it stops at a position (the position shown in FIGS. 7A and 9A) in contact with the end of.

Thus, after the completion of the general alignment,
Since the anterior eye image is again out of focus, detailed alignment is performed this time with the gantry 3 close to the eye E so that the image is in focus.

When the control circuit 80 determines from the output information of the sensors 41 and 73 that the detailed alignment has been performed, an airflow is blown out from the airflow blowing nozzle 12, and measurement of intraocular pressure is started by a known means.

Next, the case of an examiner who is skilled in the operation of the apparatus will be described.

When the examiner becomes proficient in the operation of the ophthalmologic apparatus S, in many cases, even if the anterior segment image displayed on the monitor 3a is completely out of focus, the general alignment operation is completed. Will be able to do that.

For such an examiner, the above-described mode in which the position of the objective lens 16 changes one by one between the position where the gantry 3 is separated from the eye E to be examined and the position where the gantry 3 is close to the eye E increases the entire operation time, It is rather inconvenient.

If the examiner considers that the automatic switching of the position of the objective lens 16 is unnecessary, the examiner presses the changeover switch 6a to change to the alignment position change stop mode.

In the alignment position change stop mode, not only is the gantry 3 located at a position close to the subject's eye E and the microswitch 8 is ON, but also the gantry 3 is separated from the subject's eye E and the microswitch 8 is turned on. Is turned off, the objective lens 16 is not moved toward the CCD 19 but is positioned on the nozzle 12 side.

Therefore, the trouble caused by moving the objective lens 16 is eliminated, and the final alignment can be completed more quickly.

In the case of the alignment position change stop mode, the control means 80 outputs a measurement data printout or data clear at a measurement break, for example, when the power is turned on, when switching between the left and right eyes is detected. Is operated, when the operation of the microswitch 8 is detected, the motor unit 100 is operated, and
7A is moved to a position (a position in FIG. 7A and FIG. 9A) where a contacts the end of the long hole 91b on the nozzle 12 side.

As a result, the gantry 3 vibrates and the pins 92
a is slightly deviated from the position (the position shown in FIGS. 7A and 9A) in contact with the end of the elongated hole 91b on the nozzle 12 side, the pin 92a is again moved to the nozzle 12 of the elongated hole 91b. Position will be reset to contact the side end,
The detailed alignment operation can be performed while the objective lens 16 is always at the same position.

When the alignment position change stop mode is set, a warning is displayed on the monitor 3a to notify the examiner of the change, thereby preventing an operation error.

As described above, when the examiner is a beginner unfamiliar with the operation, the position of the objective lens 16 is controlled in accordance with the position of the gantry 3 so that the movable eye can be controlled so that the subject's eye E and the gantry 3 can be moved. In the isolated state, the eye E to be inspected is focused in the separated state, and then the gantry 3 is moved closer to the eye E to be examined. In this case, the position of the objective lens 16 is controlled so that the eye E to be inspected is brought into focus in the close state, and relatively simple positioning can be performed.

When the examiner is an expert, the objective lens 16 is set to a fixed focal point at a position where the subject E and the gantry 3 are in focus when the eye E and the gantry 3 are close to each other, so that quick alignment can be achieved. It can be carried out.

Further, when the focus position is fixed by the mode switching and alignment position changing means,
When the power is turned on, when clearing, printing out, switching between the left and right eyes, and when moving the gantry 3 back and forth, the objective lens 16 is reset to a predetermined position so that the objective lens 16 remains deviated from the reference position. Alignment can be performed without any trouble without performing an operation for observation (or photographing).

[0066]

As described above, according to the ophthalmologic apparatus of the first aspect, the gantry that can approach and separate from the eye to be inspected, and the gantry for observing the anterior segment of the eye to be inspected. An anterior eye observation optical system provided; a focus position changing means for changing a focus position of the anterior eye observation optical system; and a gantry position detection for detecting a position of the gantry with respect to a subject's eye direction. Means, an ophthalmologic apparatus comprising: a focus position change control means for controlling the focus position change means based on an output from the gantry position detection means; and a prohibition means for prohibiting the operation of the focus position change means. By doing so, it is possible to switch between the case where the control of the focus position changing means is permitted and the case where the control of the focus position changing means is prohibited by the prohibition means, so that the operability can be improved for both beginners and skilled persons.

According to the ophthalmologic apparatus of the second aspect, the prohibiting means operates so as to correct the displacement of the focus position changing means due to the vibration of the apparatus main body, so that the focus position changing means always operates. The alignment operation can be performed without any deviation.

[Brief description of the drawings]

FIG. 1 is a plan layout view of a main part of an optical system of an ophthalmologic apparatus according to the present invention.

FIG. 2 is a side view of a main part of an optical system of the ophthalmologic apparatus according to the present invention.

FIG. 3 is an explanatory diagram of reflection of an alignment light beam applied to the cornea from the front.

FIG. 4 is a diagram showing an anterior segment image displayed on a monitor.

FIG. 5 is an explanatory diagram of reflection of an alignment light beam applied to a cornea from an oblique direction.

FIGS. 6A and 6B are diagrams showing the incident / reflective relationship of a light beam when the position of the cornea is shifted, wherein FIG. 6A is an explanatory diagram when the cornea is shifted in the Z direction, and FIG. FIG.

FIG. 7 is a view showing a lens holding unit, and FIG.
FIG. 3 is a cross-sectional view of the lens holding unit when the eye to be examined and the gantry are close to each other, and FIG. 2B is a cross-sectional view of the lens holding unit when the eye to be examined and the gantry are separated from each other.

8A and 8B are views showing a motor unit, wherein FIG. 8A is a plan view of the motor unit, and FIG. 8B is a side view of the motor unit.

9A and 9B are diagrams illustrating a relationship between a pin, a long hole, and an arm member, wherein FIG. 9A is a plan view of a main part when an eye to be inspected and a gantry are close to each other, and FIG. FIG. 4 is a plan view of a main part when the distance is away.

FIG. 10 is a diagram showing a microswitch, and is an explanatory diagram of a main part.

11A and 11B are diagrams illustrating an appearance of an ophthalmologic apparatus, wherein FIG. 11A is a front view of the ophthalmologic apparatus, and FIG. 11B is a side view of the ophthalmologic apparatus.

FIG. 12 is a block circuit diagram related to a main part of the present invention.

[Explanation of symbols]

E: Eye to be inspected 3: Lower gantry (gantry) 4: Upper gantry (gantry) 6 ... Switch group 6a ... Changeover switch (prohibiting means) 8 ... Micro switch (gantry position detecting means) 10 ... Anterior eye part observation optical system 80 ... Control circuit (also serves as focus position change control means / prohibition means) 90 ... Lens holding unit (focus position change means) 100 ... Motor unit (focus position change means)

Claims (2)

[Claims] 1. A gantry that can approach and separate from an eye to be examined, an anterior eye observation optical system provided in the gantry for observing an anterior eye of the eye, and an anterior eye observation optics Focusing position changing means for changing the focusing position of the system, gantry position detecting means for detecting the position of the gantry with respect to the eye to be examined, and changing the focusing position based on an output from the gantry position detecting means. An ophthalmologic apparatus comprising: a focus position change control unit that controls the unit; and a prohibition unit that prohibits an operation of changing the focus position by the focus position change unit. 2. The ophthalmologic apparatus according to claim 1, wherein said prohibiting means operates to correct a shift of said focus position changing means due to vibration of the apparatus main body.