JPH119551A - Ophthalmologic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable judgment of right and left positions and measurement of the distance between irises even by a hand-held type ophthalmologic apparatus just as by a stationary type one. SOLUTION: This ophthalmologic apparatus has an alignment means, by which the state of alignment with eyes to be inspected is detected to output a proper signal when it becomes proper, housed in a casing 1. In this case, this apparatus is also provided with a forehead pad 13 to be fixed on a subject, a moving mechanism to make the forehead pad 13 movable in the direction of the right and left eyes to be inspected to the casing 1 and an encoder 30 which detects the position in the direction of the right and left eyes to be inspected of the moving mechanism to the box body. A measuring means is provided to fetch a position signal from a detection means when the state of alignment with one eye to be inspected becomes proper out of the right and left eyes to be inspected and a proper signal is outputted from the alignment means or to fetch a position signal detected by the detection means when the state of alignment with the other eye to be inspected becomes proper out of the right and left eyes to be inspected and a proper signal is outputted, thereby calculating the distance between irises based on both the position signals.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ophthalmic apparatus such as an eye refraction measuring apparatus used in an ophthalmic clinic or an optician, and more particularly, to an ophthalmic apparatus having a function of measuring an interpupillary distance of an eye to be examined.

[0002]

2. Description of the Related Art Conventionally, as an ophthalmologic apparatus such as an eye refraction measuring apparatus, a stationary type and a handheld type have been proposed. In a stationary ophthalmologic apparatus, the face of the subject is fixed to the ophthalmic apparatus by fixing the subject's chin on the chin rest and fixing the subject's forehead on the forehead rest. Move the measuring unit of the ophthalmic device up, down, left, right, up, down,
The alignment between the apparatus and the subject's eye is performed. On the other hand, in a hand-held ophthalmologic apparatus, alignment is performed by moving the entire ophthalmic apparatus up, down, left, right, front, and back without bringing the ophthalmic apparatus into contact with the subject.

FIG. 10 shows a side view of a stationary auto-refractometer in a measurement state. In FIG. 10, the auto-refractometer is provided with a chin rest 100 and a forehead rest 101. The subject's chin is placed on the chin rest 100, and the forehead is pressed against the forehead rest 101, whereby the auto-refractometer is controlled. The position of the subject's eye is fixed. In this auto-refractometer, a slide table 103 is attached to a base 102, and a measuring unit 104 is attached to the slide table 103. The slide table 103 is attached to the base 102 using a joystick 105.
In the front-rear direction (the direction from the examiner toward the examinee is referred to as the “front direction”, and the opposite direction is referred to as the “rear direction”; the same applies hereinafter) and the left-right direction The measurement unit 104 can be moved in the vertical direction (the direction perpendicular to the front-rear and left-right directions is referred to as the “up-down direction”; the same applies hereinafter) with respect to the slide table 103. Is possible. Start switch 10
Pressing 6 starts measurement, and the examiner uses the joystick 105 to move the measuring unit 104 to a position where the optical axis 107 of the measuring unit 104 and the subject's eye are aligned, thereby performing alignment adjustment. This alignment state is monitored by an alignment unit (not shown). When the alignment state becomes appropriate, a signal indicating that the alignment state is appropriate is output from the alignment unit, and the measurement of the subject's eye is automatically started based on this signal. The measurement is performed on the other eye after the end of one eye.

[0004] Here, the base 102 is fixed to a measuring desk or the like, and is not moved before and after the measurement. Inside the slide table 103, a detection unit (not shown) that detects whether the slide table 103 is moved to the left or right with respect to the center of the apparatus by detecting the position of the slide table 103 with respect to the base 102. Is provided. When the alignment state becomes proper, the position is detected by the detection unit, and the position of the slide table 103 with respect to the center of the apparatus at that time is detected, so that the left / right discrimination of the eye currently being measured is determined. It can be carried out.
Further, by detecting the position of the eye to be examined at such a measurement point in time for both the left and right eyes to be examined, the distance between the left and right eyes to be examined is obtained, thereby measuring the distance between the left and right eyes (interpupillary distance). ) Can be performed.

FIG. 11 is a side view of a hand-held auto-refractometer in a measurement state. Generally, a hand-held auto-refractometer is not provided with a chin rest and a forehead support. However, the auto-refractometer shown in FIG. 11 has a forehead support 110 for stabilizing the relative positional relationship between the subject's eye and the apparatus. (Described in JP-A-8-164114 filed by the present applicant). In this auto-refractometer, the measurement is performed with the subject's forehead pressed against the forehead rest 110. The examiner holds the grip 111 with one hand and presses the start switch 112 to instruct the start of measurement. The examiner adjusts the alignment by moving the entire apparatus to a position where the optical axis 114 of the measuring unit 113 and the subject's eye match. Then, as in the case of the stationary type, when a signal to the effect that an appropriate signal is output from the alignment unit, the measurement of the eye to be inspected is automatically started based on this signal. The measurement is performed on the other eye after the end of one eye.

[0006]

However, in such a conventional hand-held type ophthalmic apparatus, unlike the stationary type, there is a portion that is not moved before and after the measurement, such as the stationary base 102. Instead, the entire device is moved. Therefore, the measuring unit 113 for the device
Cannot be detected, and therefore the position of the eye to be inspected with respect to the apparatus cannot be detected. For this reason, it has not been possible to perform left / right discrimination of the eye to be measured and measurement of the interpupillary distance, as performed in a stationary ophthalmic apparatus. Therefore, conventionally, it has been necessary to use another device such as a PD meter for measuring the interpupillary distance.

The present invention has been made in view of the above-mentioned problems of the conventional ophthalmic apparatus. Even in a hand-held ophthalmic apparatus, the left-right discrimination and the measurement of the interpupillary distance are performed similarly to the stationary type. The purpose is to make it possible.

[0008]

In order to solve the above-mentioned problems in the conventional ophthalmologic apparatus, the present invention according to the first aspect detects an alignment state with respect to the eye to be inspected,
In an ophthalmologic apparatus in which an alignment means for outputting a proper signal when the alignment state becomes proper is housed in a housing, a fixing means fixed to a subject, and the fixing means for the housing. A moving means capable of moving in the left and right eye direction, a detecting means for detecting a position of the moving means in the left and right eye direction with respect to the housing, and outputting a position signal; and one of the left and right eye eyes When the alignment state with respect to the eye to be examined is proper and a proper signal is output from the alignment means, the position signal from the detection means is fetched, and the alignment state with respect to the other one of the left and right eyes to be examined becomes proper, and Measuring means for receiving a position signal from the detecting means when an appropriate signal is output, and calculating an interpupillary distance based on both of the position signals. It is configured as characterized in that it comprises.

According to a second aspect of the present invention, in the first aspect of the present invention, it is determined whether the eye to be inspected is the left or right eye based on the position signal output by the detection means. It is characterized by including left and right eye discriminating means.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the fixing means determines whether or not the fixing means is fixed to the subject. It is characterized in that means are provided.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the ophthalmologic apparatus of the present invention is applied to an eye refraction measuring apparatus will be described below in detail with reference to the drawings. 1 is a side view of the ophthalmologic apparatus according to the present embodiment in a measurement state, FIG. 2 is a plan view of FIG. 1, FIG. 3 is a side view of the ophthalmologic apparatus showing a periphery of the forehead rest, and FIG. 5 is a plan view of the ophthalmologic apparatus, which is cut away, FIG. 5 is an explanatory view mainly showing a measurement unit and an alignment unit of the ophthalmologic apparatus, FIG. 6 is a front view of the light receiving element of FIG. 5, and FIG. FIG. 8 is a flowchart of the measurement of the interpupillary distance.

In FIG. 1, an ophthalmologic apparatus is an eye refraction measuring apparatus for measuring the refracting power of an eye to be examined. A housing 1 includes a measuring unit 2 as an ophthalmic unit and an alignment detecting unit 3 as an alignment unit shown in FIG. It is configured. Since the measuring unit 2 and the alignment detecting unit 3 are described in Japanese Patent Application Laid-Open No. Sho 62-5147 by the present applicant, the details are omitted, and only the outline is described.

The measuring section 2 is arranged so as to substantially face each of the left and right eyes to be examined sequentially, and as shown in FIG. 5, irradiates illumination light from an illumination light source 4 to the eye to be inspected and is reflected. Illumination light is received by the light receiving unit 5. As shown in FIG. 6, a plurality of photoelectric conversion elements 6 and 6 are arranged in the light receiving section 5, and the amount of reflected light received by the photoelectric conversion elements 6 and 6 is determined by the amount of the reflected light. , 6 as a voltage value. The measuring unit 2 calculates eye information (refractive power in the present embodiment) of the eye to be inspected based on the voltage value.

The alignment detecting section 3 shown in FIG. 5 detects an alignment state of the subject's eye with respect to the measurement optical axis of the measuring section 2 and outputs an appropriate signal when the alignment state becomes appropriate. This alignment detection unit 3
Illumination light emitted from the illumination light source 4 and reflected by the subject's eye is received by the four-division photoelectric conversion element 7 arranged in the light receiving unit 5 as shown in FIG. The four-division photoelectric conversion element 7
The amount of illumination light received by the
Is detected as a voltage value. Then, based on this voltage value, it is determined whether the subject's eye is correctly aligned with the optical axis of the measuring unit 2, that is, whether the alignment state is appropriate. When it is determined that the alignment state is appropriate, it is appropriate. And outputs an appropriate signal indicating that.

As shown in FIGS. 1 and 2, a forehead pad 10 as a fixing means and a moving mechanism 11 as a moving means are provided in the upper front of the housing 1. The forehead rest 10 and the moving mechanism 11 are the same as those described in Japanese Patent Application Laid-Open No. Hei 8-164114 by the present applicant, except for the parts described later as features of the present embodiment. I do.

First, as shown in FIGS. 1 and 3, a recessed storage section 12 is formed in the upper front of the housing 1, and before the measurement, the storage section 12 has a forehead contact 10 and a movable storage section 12. The frame 16 of the mechanism 11 is accommodated. As shown in FIGS. 1 to 4, the forehead pad 10 is a plate-shaped member that is disposed substantially parallel to the subject's forehead in a use state, easily adheres to the forehead, and is uncomfortable for the subject. Is formed from a resin so as not to give the As shown in FIGS. 3 and 4, this forehead 10 has a feature of this embodiment.
By detecting the pressure applied to 0, the forehead 1
A pressure sensing unit 13 is provided as fixing determination means for determining whether 0 is fixed to the subject's forehead.
Note that the pressure sensing unit 13 is configured by a limit switch or a piezoelectric element.

As shown in FIG. 3 and FIG. 4, the moving mechanism 11 has two ends fixed to the back surface of the frame 16 (the surface opposite to the surface facing the subject) and parallel to each other. Slide rods 14, 14, frame 16 and forehead 10
A spring 15 for biasing the frame 16 and the frame 16 and the forehead pad 10 in the storage unit 12. At the time of non-measurement, the slide rod 14 is housed in the housing 1 by the holding unit 25, and therefore, the frame 16 and the forehead pad 10 are held in a state of being housed in the housing unit 12 as shown in FIGS. You. On the other hand, at the time of measurement, the slide rod 14 protrudes forward from the inside of the housing 1 by the urging force of the spring 15, so that the frame 16 and the forehead pad 10 protrude from the storage section 12 as shown in FIGS. Becomes

Here, the moving mechanism 11 not only allows the forehead pad 10 to be moved in and out of the storage section 12 but also has a feature of the present embodiment that the forehead pad 10 can be moved in the right and left directions with respect to the housing 1. Can be moved. Hereinafter, a mechanism for this will be described. The mechanism for this lateral movement is constituted by a frame 16, a shaft 17 and a bearing 18. As shown in FIG. 4, the frame 16 is a frame having a horizontally long U-shape in cross section. The opening side is the front side, and its longitudinal direction is substantially parallel to the left and right eye directions at the time of measurement. Are located in The axis 17 is the frame 1
6 are arranged along the longitudinal direction, and are fixed to the frame 16 at both ends. The bearing 18 is the shaft 1
7 is provided so as to be immovable in the front-rear direction and movable in the left-right direction. The forehead rest 10 is fixed in front of the bearing 18,
Is movable in the left-right direction with respect to the housing 1 via the bearing 18, the shaft 17, and the frame 16.

As shown in FIG. 4, the moving mechanism 11 is provided with a center moving mechanism 19 for moving the forehead rest 10 substantially to the center in the left-right direction of the housing 1 at the time of initialization. The center moving mechanism 19 includes a wire 20 fixed to both left and right sides of the bearing 18, a fixing portion 21 for fixing an end of the wire 20 inside the housing 1, and a support 22 arranged near the fixing portion 21. And a support motor 23 shown in FIG. 7 for moving the support 22 between two points P1 and P2. The strut motor 23 moves the strut 22 to the point P1 by receiving a release signal from a control unit described later. In the state in which the column 22 has moved to the point P1, the wire 20 is in a slack state between the bearing 18 and the fixed portion 21, so that the bearing 18 is not hindered by the wire 20, so that the forehead 10 is not in the housing. The body 1 is movable in the left-right direction.

On the other hand, the strut motor 23 moves the strut 22 to a point P2 by receiving a regulation signal from a control unit described later.
Move to In the state in which the column 22 has moved to the point P2, the wire 20 is pulled by the column 22 between the bearing 18 and the fixing portion 21, so that the bearing 18 is pulled by the wire 20. Wire 20
Length of the bearing 1 when the wire 20 is pulled.
8 is determined so as to be located substantially at the center of the housing 1 in the left-right direction. Therefore, the bearing 18 is located at the approximate center, and the forehead pad 10 is located at the approximate center.

Here, as shown in FIGS. 3 and 4, the present apparatus is provided with an encoder 30 which detects a relative position of the bearing 18 in the left-right direction with respect to the housing 1 and outputs a position signal. ing. The encoder 30 includes a slit plate 31, a sensor 32, and a position calculator 33 shown in FIG. Of these, the slit plate 31
A plate-like member having substantially the same length as the length of the frame 16 in the longitudinal direction, and is fixed to the surface of the frame 16 facing the subject along the longitudinal direction of the frame 16. Optical slits composed of an absolute pattern and an incremental pattern are formed on the slit plate 31 at regular intervals. On the other hand, the sensor 32 is fixed to the surface of the bearing 18 on the side of the slit plate 31 so as to face the slit plate 31. The sensor 32 projects the measurement light to the slit plate 31, receives the measurement light reflected by the slit plate 31, and outputs the received light amount as a voltage value. The value is input to the position calculation unit 33 and the bearing 18 for the slit plate 31 is
, That is, the relative position of the forehead rest 10 with respect to the housing 1 is calculated. It should be noted that an encoder for detecting such a relative position is well known, and a detailed description thereof will be omitted.

Next, the electrical configuration of the apparatus will be described with reference to the block diagram of FIG. In FIG. 7, the measurement switch 40, the measurement unit 2, the alignment detection unit 3, the pressure sensing unit 13,
A storage unit 41, a sensor 32, a position calculation unit 33, a column motor 23, a distance measurement unit 34, a left and right eye determination unit 42, an alarm output unit 43, a display unit 44, and a control unit 45 are shown.
Among them, the measuring unit 2, the alignment detecting unit 3, the pressure sensing unit 1
3, sensor 32, position calculation unit 33, and column motor 2
3 has already been described. The measurement switch 40 is pressed by the examiner to instruct the measurement section 2 to start measurement, and is provided at the upper front part of the handle 24 as shown in FIG. The storage unit 41 stores the position calculated by the position calculation unit 33.

When a proper signal is output from the alignment detecting unit 3 in a state where the measuring unit 2 is arranged to face one of the left and right eyes to be examined, the distance measuring unit 34 detects the position signal detected by the encoder 30. When an appropriate signal is output from the alignment detection unit 3 in a state where the measurement unit 2 is placed facing the other of the left and right eyes to be examined, the encoder 3
The position signal detected at 0 is taken in, and the pupil distance is calculated based on both position signals. The left and right eye discriminating section 42 discriminates which of the left and right eyes to be inspected is the eye to be inspected measured by the measuring section 2 based on the position signal detected by the encoder 30. Details of the distance measurement unit 34 and the left and right eye determination unit 42 will be described later. Based on the signal from the control unit 45, the alarm output unit 43 appropriately applies the forehead rest 10 to the subject's forehead from the start of the measurement to the end of the measurement of the left and right eyes. An alarm is output when an error occurs. The display unit 44 displays various values such as measured values. Control unit 45
Is a measuring switch 40, a measuring unit 2, an alignment detecting unit 3, a pressure sensing unit 13, a storage unit 41, a sensor 32, a position calculating unit 33, a support motor 23, a distance measuring unit 34, a left and right eye discriminating unit 42, and an alarm output. It controls the unit 43 and the display unit 44.

Next, the operation of the present apparatus for measuring the distance between pupils will be described with reference to the block diagram of FIG. 7 and the flowchart of FIG. First, the examiner pulls the moving mechanism 11 shown in FIG. 4 to the side opposite to the housing 1 so that the frame 16 and the forehead pad 10 are protruded from the storage unit 12. Then, as shown in FIG. 8, when the power of the apparatus is turned on (step S1) and the measurement switch 40 is pressed (step S1).
2) When the alignment state becomes appropriate, the measurement is automatically started. When the apparatus is turned on, the pressure sensing unit 13 of FIG. 4 always determines whether the forehead rest 10 is fixed to the subject's forehead, and a signal indicating the determination result is constantly controlled. Input to the unit 45.
In the control unit 45, while the signal indicating that the forehead rest 10 is not fixed is input from the pressure sensing unit 13,
3 to output a regulation signal. The support motor 23 to which the regulation signal has been output moves the support 22 of FIG. 4 to the point P2, and as a result, the forehead rest 10 is disposed substantially at the center of the housing 1 in the left-right direction. Further, at the time when the forehead rest 10 is arranged substantially at the center in the left-right direction, the position of the forehead rest 10 output from the position calculating unit 33 is used as the reference position in the storage unit 41.
Is stored. For example, “0 mm” is stored as the reference position.

Then, as shown in FIG. 1, the examiner presses the forehead rest 10 approximately at the center of the subject's forehead in the left-right direction. Then, a signal indicating that the forehead rest 10 is fixed to the subject's forehead is input from the pressure sensing unit 13 to the control unit 45.
The control unit 45 outputs a release signal to the column motor 23 while the signal indicating that the forehead rest 10 is fixed is input. The post motor 23 for which the release signal has been output is shown in FIG.
Is moved to the point P1, and as a result,
Can move freely in the left-right direction. The control unit 45
After the signal indicating that the forehead rest 10 is fixed to the subject's forehead is input from the pressure sensing unit 13 once,
Always monitor the input signal from the pressure sensing unit 13 and the measurement state in the measurement unit 2, before the measurement of the left and right eyes to be examined is completed,
When a signal indicating that the forehead rest 10 is not fixed to the subject's forehead is input from the pressure sensing unit 13, the forehead rest 1
It is determined that the state of 0 is inappropriate, and the alarm output unit 43 outputs an alarm.

The examiner moves the apparatus to the side of the left or right eye to be measured first, for example, the left eye to be examined, while pressing the forehead rest 10 against the forehead of the examinee. The optical axis of is adjusted to the eye to be examined. When the optical axis of the measurement unit 2 is aligned with the eye to be inspected, that is, when the alignment state of the eye to be inspected with respect to the measurement unit 2 is appropriate, an appropriate signal indicating the appropriateness is sent from the alignment detection unit 3 to the distance measurement unit. 34 and the control unit 45 (step S3 in FIG. 8).

The control unit 2, which has output the appropriate signal from the alignment detecting unit 3, takes in the measurement result of the measuring unit 2 at that time, thereby automatically measuring the refractive power (S4 in FIG. 8). . Further, the distance measuring unit 34 to which the appropriate signal has been output captures the position of the forehead 10 output from the position calculating unit 33 at that time. The position captured by the distance measurement unit 34 is temporarily output to the control unit 45, sent from the control unit 45 to the storage unit 41, stored in the storage unit 41, and stored in the control unit 45.
Is sent to the left and right eye determination unit 42 (S5 in FIG. 8).

In the left and right eye discriminating section 42, based on the position sent from the control section 45 and the reference position stored in the storage section 41, the eye currently being measured by the measuring section 2 is determined to be either left or right. It is determined whether the eye is the subject's eye. For example, if the position sent from the control unit 45 is “40 mm” and the reference position stored in the storage unit 41 is “0 mm”, the position exists in the direction in which the position increases with respect to the center position of the left and right subject eyes. It can be seen that the eye to be examined is measured. Here, since the direction in which the position increases is determined in advance by the pattern of the optical slit formed in the slit plate 31, the direction of the increase with respect to the central position of the housing 1 is determined by the left and right eye discriminating unit. 42 can be set in advance. For example, if the increasing direction is set in advance to the right as viewed from the examiner, the eye being measured by the measurement unit 2 is determined to be the left eye. Such a determination result of the left and right eye determination unit 42 is output to the control unit 45, and the control unit 45 adds the left and right determination result to the measurement value obtained by the measurement unit 2.

When the measurement of one eye is completed as described above, in order to perform the measurement of the other eye, the apparatus is moved only while the forehead rest 10 is in contact with the subject's forehead, and the measurement unit 2 is moved to the other side. It is made to face the eyes (S6 in FIG. 8). For example, at this point,
If the forehead rest 10 deviates from the subject's forehead, the forehead rest 1
A signal indicating that 0 is not fixed to the subject's forehead is input from the pressure sensing unit 13 to the control unit 45. When such a signal is input before the measurement of the left and right eyes to be examined is completed, the control unit 45 causes the alarm output unit 43 to output an alarm, for example, a buzzer. The examiner knows the improper state of the forehead pad 10 by this alarm and repeats the measurement.

On the other hand, when the apparatus is moved while the forehead rest 10 is appropriate, the alignment detecting unit 3 determines the alignment state (S7 in FIG. 8), and when the optical axis of the measuring unit 2 matches the eye to be examined. Is automatically measured in the same manner as described above (S8 in FIG. 8), and the forehead
Is captured by the distance measurement unit 34 (S in FIG. 8).
9), is stored by the storage unit 41. Further, the distance measuring unit 34 calculates the interpupillary distance from the two positions stored by the storage unit 41. For example, if two positions are "40m
m ”and“ −38 mm ”, the interpupillary distance is set to“ 78 m
m ”(S10 in FIG. 8). This calculation result is sent to the storage unit 41 via the control unit 45, and the storage unit 41
Is stored by

This completes the measurement of the left and right eyes, and the measured results are displayed on the display unit 44 (not shown) together with the left and right eye discrimination results stored in the storage unit 41. At the same time, the interpupillary distance is also displayed. (S11 in FIG. 8), and all operations end (S12 in FIG. 8). When the measurement is completed and the examiner removes the forehead rest from the subject's forehead, a signal indicating that the forehead rest 10 is not fixed to the subject's forehead is sent to the pressure sensing unit 1.
3 is input to the control unit 45. In the control unit 45, when a signal indicating that the forehead rest 10 is not fixed to the forehead of the subject is input from the pressure sensing unit 13 after the measurement of the left and right eyes to be examined is completed, the support motor 23 Output the regulation signal to The support motor 23 to which the regulation signal has been output moves the support 22 of FIG. 4 to the point P2. As a result, the forehead rest 10 is arranged substantially at the center of the housing 1 in the left-right direction, and the next measurement preparation is prepared. .

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea. Therefore, these different modes will be described below. First, in the above-described embodiment, an example in which the present invention is applied to an eye refraction measuring apparatus is shown. However, the present invention is not limited to the eye refraction measuring apparatus, but may be applied to any ophthalmologic apparatus that wants to measure the interpupillary distance, such as a corneal shape measuring apparatus. May be applied.

The fixing means fixed to the subject does not necessarily have to be formed as a forehead rest, but may be, for example, a chin rest. Further, the structure for moving the fixing means is not limited to the above-described embodiment, and any known structure may be employed. For example, in the above-described embodiment, the encoder is configured to protrude toward the subject along with the forehead rest. Although the encoder has been described as detecting the relative position of the forehead contact, it may be configured to detect the absolute position.

When the forehead is applied to the subject in an inclined state, the interpupillary distance measured by the above method may be different from the actual interpupillary distance. For example, in FIG. 9, the ophthalmologic apparatus in a state where the forehead rest is not inclined with respect to the subject is indicated by a dashed line, and the interpupillary distance in this case is PD1, while the forehead rest is inclined with respect to the subject. The ophthalmologic apparatus in a state of being turned is shown by a solid line, and the interpupillary distance in that case is PD2. In this case, the interpupillary distance to be obtained, that is, the actual interpupillary distance is PD1, but the interpupillary distance measured by the above method is PD2. Therefore, it is necessary to obtain the actual interpupillary distance PD1 from the measured interpupillary distance PD2.

For this reason, when the left and right eyes to be examined are measured by the present apparatus, the amount of movement (slide amount) of the forehead rest in the front-back direction is monitored, and the left and right eyes to be examined are measured. If the amount of movement before and after the forehead application changes by a predetermined value or more between when the measurement is performed, it is determined that the measurement was performed with the forehead application inclined with respect to the subject. This is because on the premise that the protruding amounts of the left and right eyes to be examined are the same, the forehead abutment does not move in the front-rear direction unless the forehead abutment is inclined. If it is determined that the measurement has been performed with the forehead rest inclined, assuming that the amount of movement of the forehead rest is A and the inclination is θ, the inclination θ is obtained from tan θ = A / PD2, and PD1 cos θ = PD2 The interpupillary distance PD1 to be obtained more can be obtained.

[0036]

According to the first aspect of the present invention, as described above, the fixing means fixed to the subject and the housing
A moving unit that enables the fixing unit to move in the left and right eye directions, a detecting unit that detects the position of the moving unit with respect to the housing in the left and right eye direction, and outputs a position signal; When the alignment state with respect to the subject's eye is proper and the proper signal is output from the alignment means, the position signal from the detecting means is taken in, and the alignment state with respect to the other one of the left and right subject's eyes becomes proper and the proper signal from the alignment means is obtained. Is output, the position signal from the detection means is taken in, and the measurement means for calculating the interpupillary distance based on these two position signals is provided, so that the interpupillary distance can be easily set even in a handheld ophthalmic apparatus. Can be calculated. Therefore, there is no need to use a separate PD measuring device. Further, the pupil distance is calculated almost simultaneously with the measurement by the measuring means, so that the measurement efficiency is improved.

Further, according to the present invention, the left and right eye discriminating means for discriminating whether the eye to be inspected is the left or right eye based on the position signal output by the detecting means is provided. Since the eye to be inspected is the left or right eye to be inspected, and there is no need to input separately, the workability and reliability are improved.

According to the third aspect of the present invention, the fixing means is provided with a fixing determining means for determining whether the fixing means is fixed to the subject. It is easy to detect whether it is appropriate or not,
An alarm can be issued when the forehead contact is deviated, and the pupil distance calculation reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a side view in a measurement state of an ophthalmologic apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of the ophthalmologic apparatus of FIG.

FIG. 3 is a side view of the ophthalmologic apparatus with the forehead rest broken.

FIG. 4 is a plan view of the ophthalmologic apparatus of FIG.

FIG. 5 is an explanatory diagram mainly showing a measurement unit and an alignment detection unit of the ophthalmologic apparatus in FIG. 1;

FIG. 6 is a front view of the light receiving element of FIG.

FIG. 7 is a block diagram illustrating an electrical configuration of the ophthalmologic apparatus of FIG. 1;

FIG. 8 is a flowchart of the measurement of the interpupillary distance.

FIG. 9 is a plan view of the ophthalmologic apparatus for explaining a case where the interpupillary distance is corrected.

FIG. 10 is a side view of a conventional stationary ophthalmic apparatus in a measurement state.

FIG. 11 is a side view of a conventional handheld ophthalmic apparatus in a measurement state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Measuring part 3 Alignment detecting part 4 Illumination light source 5 Light receiving part 10, 101, 110 Forehead support 11 Moving mechanism 12 Depression 13 Pressure sensitive part 17 Axis 18 Bearing 20 Wire 30 Encoder 31 Slit plate 32 Sensor 33 Position calculating part 34 Distance measuring unit 42 Left and right eye discriminating unit

Claims (3)

[Claims] 1. An ophthalmologic apparatus comprising: a housing; and an alignment means for detecting an alignment state with respect to the subject's eye and outputting a proper signal when the alignment state becomes proper. Fixing means, moving means for moving the fixing means in the left and right eye directions with respect to the housing, and detecting the position of the moving means with respect to the housing in the left and right eye directions. Detecting means for outputting a signal; and when the alignment state with respect to one of the left and right eyes to be examined is proper and a proper signal is output from the alignment means, a position signal from the detecting means is taken in, and the left and right eyes to be examined are output. When the alignment state with respect to the other eye to be examined becomes proper and a proper signal is output from the alignment means, the position signal from the detection means is obtained. And a measuring means for calculating an interpupillary distance based on these two position signals. 2. The apparatus according to claim 1, further comprising left and right eye discriminating means for discriminating which of the right and left eyes to be examined based on the position signal output by said detecting means.
The ophthalmic apparatus according to the above. 3. An ophthalmologic apparatus according to claim 1, wherein said fixing means is provided with fixing determining means for determining whether said fixing means is fixed to said subject. .