JP5706508B2 - Ophthalmic equipment - Google Patents

Description

  The present invention relates to an ophthalmic apparatus.

  The “interpupillary distance” refers to the distance between the pupil center of one eye of the subject and the pupil center of the other eye.

  For example, when creating spectacles, it is possible to provide spectacles in consideration of individual differences by determining the distance between the optical centers of the right and left spectacle lenses based on the interpupillary distance.

  The interpupillary distance is said to be 62 to 64 mm on average for general adults. Strictly speaking, however, the distance depends on the size and arrangement of each person's eyes. Therefore, various apparatuses have been studied in order to accurately perform the measurement.

  For example, Patent Document 1 describes an optometry apparatus that calculates the interpupillary distance based on the distance between the measurement head unit 5 and the initial position of the center of the stage table 3 and the movement distance of the stage table 3 (Patent Document 1). [0027] etc.).

  Further, the ophthalmologic apparatus of Patent Document 2 is provided with a CCD camera 52 for simultaneously photographing both eyes in addition to the measurement unit 3 that performs refractive power measurement. There is a description that the interpupillary distance can be obtained from an image photographed by the CCD camera 52 (see Patent Document 2 [0039], etc.).

Japanese Patent Laid-Open No. 9-266887 JP-A-10-216089

  However, in the configuration described in Patent Document 1, after measuring the refractive power of one eye, the interpupillary distance cannot be obtained unless the refractive power of the other eye can be measured. Therefore, when the subject moves while measuring one eye and the other eye, accurate interpupillary distance measurement cannot be performed. Therefore, the subject has to maintain a state where his face is fixed to the optometry apparatus during the examination, and there is a problem that the examination burden is large.

  In addition, after calculating the interpupillary distance, if a question arises about the refractive power measurement result of one eye, it is necessary to redo the alignment adjustment. However, in this case, since the positional relationship between the face of the subject, which is the basis for calculating the interpupillary distance, and the measurement unit is not accurate, the reliability of the already calculated interpupillary distance is low. Therefore, even if there is no doubt about the measurement result of the other eye, it is necessary to measure both eyes again. In such a case, there is a problem that the inspection burden further increases.

  Furthermore, the arrangement of the eyes varies depending on the person, and the measurement method as described in Patent Document 1 cannot cope with the deviation in the vertical direction or the front-rear direction. That is, when both eyes of a certain person are viewed from the front, the distance in the horizontal direction can be obtained accurately in the configuration of Patent Document 1, but the shift in the vertical direction and the depth direction cannot be considered. Therefore, when the subject's face is tilted in the vertical direction or the depth direction, the configuration of Patent Document 1 cannot accurately measure the interpupillary distance.

  On the other hand, in Patent Document 2, since the interpupillary distance is calculated from an image obtained by simultaneously photographing both eyes, it can be said that the examination burden is reduced compared to Patent Document 1.

  However, the image photographed by the CCD camera 52 of Patent Document 2 is an image photographed before alignment. Therefore, since the exact positional relationship between the CCD camera 52 and the subject's face is not known (working distance (hereinafter referred to as “WD”) is not taken into account), accurate interpupillary distance measurement cannot be performed.

  The present invention has been made in view of the above-described problems, and the object of the present invention is to perform highly accurate interpupillary distance measurement while minimizing the examination burden on the subject. Is to provide a special ophthalmic apparatus.

  Note that “alignment” means that the measurement unit is arranged at a position (measurement position) where the eye to be measured can be appropriately measured. In alignment, the position of the measurement unit is adjusted vertically and horizontally with respect to the eye to be examined, and the position is also adjusted in the front-rear direction. When the alignment is not adjusted, accurate measurement cannot be performed on the eye to be examined. In the present invention, “position adjustment” is synonymous with “alignment”.

  “WD” refers to the distance between the measurement unit and the eye to be examined after alignment. An accurate measurement value can be obtained by measuring the eye to be examined in a state where the measurement unit is arranged at the position corresponding to the WD, that is, the measurement position.

  Further, in this specification, when the state where the subject puts his face on the ophthalmic apparatus is viewed from the examiner side, the horizontal direction is the “X direction”, the vertical direction is the “Y direction”, and the front and rear direction is “ It is defined as “Z direction” (see FIG. 1).

In order to solve the above-mentioned problem, the invention described in claim 1 includes an optical system for inspecting at least one eye of a subject and one or more imaging units capable of simultaneously imaging both eyes of the subject. A position adjustment unit that adjusts the position of the optical system and one eye of the subject, and an interpupillary distance calculation that calculates the interpupillary distance of the subject based on an image acquired by the imaging unit and parts, the optical system, the imaging unit and have a control capable of controlling unit each of the interpupillary distance calculation section, after the position adjustment unit has performed the position adjustment, the control unit after the position adjustment In this position, the imaging unit performs imaging, and the interpupillary distance calculation unit calculates the interpupillary distance based on an image obtained by imaging performed after the position adjustment .
The invention according to claim 2 is the ophthalmologic apparatus according to claim 1 , further comprising a moving unit for moving the optical system, wherein the control unit is calculated by the interpupillary distance calculating unit. The optical system is moved to the vicinity of the other eye of the subject by controlling the moving unit based on the interpupillary distance .

  According to the present invention, it is possible to perform highly accurate interpupillary distance measurement while minimizing the examination burden on the subject.

It is a figure which shows the whole image of the ophthalmologic apparatus seen from the examiner side. It is a figure which shows the whole image of the ophthalmologic apparatus seen from the subject side. 3 is a block diagram illustrating an example of a configuration of a control system of the ophthalmologic apparatus according to Embodiment 1. FIG. 4 is a flowchart illustrating an outline of processing performed by the ophthalmologic apparatus according to the first embodiment. 10 is a flowchart illustrating an outline of processing performed by the ophthalmologic apparatus according to the second embodiment. 10 is a flowchart illustrating an outline of processing performed by the ophthalmologic apparatus according to Embodiment 3. FIG. 10 is a block diagram illustrating an example of a configuration of a control system of an ophthalmologic apparatus according to a fourth embodiment. 10 is a flowchart illustrating an outline of processing performed by the ophthalmologic apparatus according to the fourth embodiment. FIG. 10 is a block diagram illustrating an example of a configuration of a control system of an ophthalmologic apparatus according to a fifth embodiment. 12 is a flowchart illustrating an outline of processing performed by the ophthalmologic apparatus according to the fifth embodiment.

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

[Embodiment 1]
1 to 4 relate to the first embodiment of the present invention.

  1 and 2 are views showing an overall image of the ophthalmologic apparatus according to this embodiment. FIG. 1 is an overall image seen from the examiner (doctor, nurse, etc.) side, and FIG. 2 is an overall image seen from the subject side.

  The ophthalmologic apparatus 1 has a box-shaped main body 2. An operation section 3 for performing various operations is provided on the inspector side of the main body section 2. For example, the base unit 4 can be freely moved in the XYZ directions by operating the operation unit 3. The base unit 4 constitutes a moving unit of the ophthalmologic apparatus 1. Further, the position adjustment and the refractive power measurement can be started by pressing an operation switch 3A provided in the operation unit 3. The remote controller 5 can also be used to perform various operations. The operation unit 3, the operation switch 3A, and the remote controller 5 may be collectively referred to as an “operation instruction unit”.

  A monitor 6 for displaying various measurement results and the like is provided on the inspector side of the main body 2.

  On the other hand, a chin rest 7 for fixing the subject's face is provided on the subject side of the main body 2. The chin rest 7 has a chin rest 8, a forehead rest 9 and a chin rest handle 10.

  The chin receiving portion 8 is a member for placing the subject's chin. The forehead pad 9 is a member for applying the forehead of the subject. The face of the subject is fixed to the chin rest 7 by the chin rest 8 and the forehead rest 9. Further, by operating the chin rest handle 10, the chin rest 7 can be placed at a position corresponding to the height of the face of the subject. Note that the position adjustment and interpupillary distance measurement performed in this embodiment are performed with the subject's face fixed to the chin rest 7.

  Further, a refractive power measuring unit 11 and an imaging unit 12 are arranged on the subject side of the main body unit 2.

  The refractive power measurement unit 11 stores an optical system and an imaging system (not shown). Using these optical systems and imaging systems, the refractive power measuring unit 11 measures the refractive power of the eye of the subject.

  The imaging unit 12 is a small camera having a function of simultaneously imaging both eyes of the subject. The imaging unit 12 needs to be provided at a position where both eyes can be imaged with the subject's face fixed to the chin rest 7. Therefore, it is desirable to arrange in the vicinity of the refractive power measuring unit 11 as shown in FIG.

  In addition, a control system 13 that controls various operations of the ophthalmic apparatus is mounted in the main body 2.

  Next, the control system 13 of this embodiment will be described in detail with reference to the block diagram of FIG.

  In the present embodiment, the control system 13 includes at least a position adjustment information determination unit 14, an interpupillary distance calculation unit 15, and a control unit 16.

  The position adjustment information determination unit 14 determines a condition (position adjustment information) such that the refractive power measurement unit 11 becomes an appropriate measurement position with respect to one eye of the subject based on an instruction from the control unit 16. . The position adjustment information is stored in advance in the position adjustment information determination unit 14. Then, the position adjustment information determination unit 14 sends the determined position adjustment information to the control unit 16. In the present embodiment, the position adjustment information determination unit 14 and the control unit 16 are collectively referred to as a “position adjustment unit”.

  The control unit 16 operates the main body unit 2 including the refractive power measurement unit 11 based on the condition determined by the position adjustment information determination unit 14, and positions the refractive power measurement unit 11 at an appropriate position with respect to the eye of the subject. The control to be arranged in. When the position adjustment of the refractive power measurement unit 11 is completed, the control unit 16 next controls the operation of the imaging unit 12 so as to perform imaging of both eyes of the subject.

  The image captured by the imaging unit 12 is sent to the interpupillary distance calculation unit 15 via the control unit 16. Then, the interpupillary distance calculation unit 15 calculates the interpupillary distance from the image.

  Data relating to the calculated interpupillary distance is displayed on the monitor 6, for example. Further, the data relating to the calculated interpupillary distance can be output by a printer (not shown).

  The series of control operations by the control unit 16 is performed by an instruction from the operation instruction unit. Further, in the present embodiment, the control unit 16 controls so as to automatically perform from the position adjustment to the calculation of the inter-pupil distance. On the other hand, the photographing by the photographing unit 12 and the calculation of the interpupillary distance can be performed by an instruction input from the operation instruction unit each time.

  Next, the operation of this embodiment will be described with reference to FIG.

  When the examination by the ophthalmologic apparatus is started, first, position adjustment between one eye of the subject and the refractive power measurement unit 11 is performed (S11, corresponding to the first position adjustment step). Thereby, the refractive power measurement part 11 can be arrange | positioned in the position which can perform an appropriate measurement with respect to one eye of a subject.

  Next, the imaging unit 12 simultaneously images both eyes of the subject (S12, corresponding to the first simultaneous imaging step). The photographed image has position information in the X and Y directions of both eyes of the subject (including information related to a shift in the X direction and Y direction of the other eye with respect to one eye).

  Next, based on the image acquired in S12, the interpupillary distance calculation unit 15 calculates the interpupillary distance (S13). Note that the image acquired in S12 is obtained by shooting with the WD determined. Therefore, the distance in the real space can be calculated based on the image and WD. For this calculation, a general distance calculation method such as triangulation can be used.

  By performing the operations from S11 to S13, the interpupillary distance can be calculated in consideration of the deviation in the XY directions in one binocular imaging. That is, it is possible to calculate the interpupillary distance with higher accuracy (considering even the deviation in the Y direction) while reducing the examination burden on the subject.

  The refractive power measurement for one eye of the subject may be performed at any timing as long as the position adjustment is completed.

[Embodiment 2]
FIG. 5 relates to the second embodiment of the present invention. Note that the configuration of the present embodiment has many parts in common with the first embodiment, and therefore different parts are mainly described.

  With the configuration of the first embodiment, it is possible to calculate the interpupillary distance in consideration of the deviation in the XY directions of both eyes. However, depending on the arrangement of both eyes, there may be a shift in the Z direction in addition to the XY direction (for example, when the other eye is deep with respect to one eye). The second embodiment relates to the calculation of the interpupillary distance in consideration of such a deviation in the Z direction.

  The ophthalmologic apparatus according to the present embodiment has the same configuration as that of the first embodiment, but the control operation in the control system 13 is different. Therefore, the operation will be described with reference to the flowchart of FIG.

  When the examination by the ophthalmologic apparatus is started, as in the first embodiment, first, position adjustment between one eye of the subject and the refractive power measuring unit 11 is performed (S21, corresponding to the first position adjustment step). Then, both eyes of the subject are simultaneously photographed by the photographing unit 12 (S22, corresponding to the first simultaneous photographing step).

  Thereafter, the refractive power measuring unit 11 is arranged in the vicinity of the other eye by the operation of the base unit 4 (moving unit) (S23). The photographing unit 12 is provided integrally with the refractive power measuring unit 11. Therefore, as the refractive power measuring unit 11 moves, the photographing unit 12 is also moved to the vicinity of the other eye.

  Next, position adjustment between the other eye of the subject and the refractive power measurement unit 11 is performed (S24, corresponding to the second position adjustment step). Thereby, the refractive power measurement unit 11 is disposed at a position where appropriate measurement can be performed on the other eye.

  After the position adjustment in S24 is completed, both eyes of the subject are photographed simultaneously by the photographing unit 12 (S25, corresponding to the second simultaneous photographing step). At least two of the images acquired at the position where the position adjustment of one eye and the refractive power measurement unit 11 is completed at this time point and the image acquired at the position where the positional adjustment of the other eye and the refractive power measurement unit 11 is completed. One image will be obtained.

  In the next step, the interpupillary distance calculation is performed by the interpupillary distance calculation unit 15 based on the two images (S26). Note that the images acquired in S22 and S25 are obtained by shooting with the WD determined. Therefore, the distance in the real space can be calculated based on the image and WD. For example, combining general methods such as grasping the position of both eyes in the tertiary space using a 3D image construction method using binocular parallax in two images and calculating the interpupillary distance based on these position information Can be used.

  By performing the operations from S21 to S26 described above, the interpupillary distance can be calculated in consideration of not only the XY direction but also the shift in the Z direction of both eyes. Therefore, it is possible to calculate the interpupillary distance with higher accuracy than in the first embodiment.

  In the second embodiment, the interpupillary distance is obtained from two images. However, the process of S26 can be performed based on a plurality of images obtained by repeating the steps S21 to S25 a plurality of times. It is. In this case, the accuracy of the calculation result by the interpupillary distance calculation unit 15 is higher.

[Modification of Embodiment 2]
In S23 of the second embodiment, when the main body 2 (refractive power measurement unit 11 and imaging unit 12) is moved from one eye to the other eye, the main body unit can be grasped to some extent in the positional relationship between the eyes. 2 and subsequent processing steps can be performed smoothly.

  Here, the positional relationship on the XY coordinates of both eyes can be grasped from the image acquired in S22. Therefore, when moving the main body 2 in S23, it can be considered that the displacement of the other eye relative to one eye is obtained from the image acquired in advance in S22, and the main body 2 is moved based on the displacement. This control is performed by the control unit 16.

  In this case, since the movement to the other eye becomes easy, the processing steps after S24 can be performed smoothly. As a result, the test time can be shortened, and the test load on the subject can be reduced.

[Embodiment 3]
FIG. 6 relates to the third embodiment of the present invention. Note that the configuration of the present embodiment has many parts in common with the first embodiment, and therefore different parts are mainly described.

  When the WD is short, the distance between the refractive power measurement unit 11 arranged at the measurement position and the eye to be examined is close. In this case, in order to photograph both eyes with the photographing unit 12 provided in the vicinity of the refractive power measuring unit 11, a camera having a large angle of view (wide angle camera) is required.

  However, an image taken with a wide-angle camera has a problem that the image is distorted toward the end. That is, when both eyes are photographed using a wide-angle camera, the shape of both eyes is drawn distorted, and there is a possibility that an accurate interpupillary distance cannot be obtained. The third embodiment relates to the calculation of the interpupillary distance considering the case where such a wide-angle camera is used.

  The ophthalmologic apparatus according to the present embodiment has the same configuration as that of the first embodiment, but the control operation in the control system 13 is different. Therefore, the operation will be described with reference to the flowchart of FIG.

  When the examination by the ophthalmologic apparatus is started, first, position adjustment between one eye of the subject and the refractive power measuring unit 11 is performed (S31, corresponding to the first position adjustment step). Next, the imaging unit 12 simultaneously images both eyes of the subject (S32, corresponding to the first simultaneous imaging step). Then, based on the image acquired in S32, the interpupillary distance calculation unit 15 calculates the interpupillary distance (S33).

  Here, in the interpupillary distance calculation unit 15, based on the interpupillary distance calculated in S12, the distance (for example, the obtained interpupillary distance) to which the main body unit 2 (refractive power measurement unit 11 and imaging unit 12) should be moved. Half of the distance) is calculated (S34). Note that it is desirable to obtain this moving distance in consideration of the angle of view of the wide-angle camera.

  The base unit 4 (moving unit) moves the main body unit 2 to a predetermined position based on the calculation result in S34 (S35).

  The imaging unit 12 performs binocular imaging again at the position moved in S35 (S36, corresponding to the third simultaneous imaging step). This position is a position where the binocular image obtained is not distorted (at least a position where the influence of the distortion is small) even when a wide-angle camera is used for the photographing unit 12.

  Then, the interpupillary distance calculation unit 15 calculates a new interpupillary distance that is less affected by the distortion of the wide-angle camera based on the captured image in S36 (S37).

  By performing the above operations from S31 to S37, it is possible to measure the interpupillary distance in consideration of the displacement in the XY directions while eliminating the influence of using the wide-angle camera. Therefore, it is possible to calculate the interpupillary distance with high accuracy regardless of the camera to be used.

  The series of operations is controlled by the control unit 16.

[Embodiment 4]
7 and 8 relate to the fourth embodiment of the present invention. Note that the configuration of the present embodiment has many parts in common with the first embodiment, and therefore different parts are mainly described.

  In general, the refractive power and the interpupillary distance are measured with the eye to be examined fixed. The fixation state is a state of staring at a point in the front, that is, a state of looking at the fovea, and is performed by displaying a visual target on the measurement optical path of the refractive power measurement unit 11 and staring at the subject.

  By the way, the position of the center of the pupil of a squint subject is greatly different between a fixed state and a non-fixed state. Moreover, since the state which is not fixation is normal, the distance between pupils obtained in the state of fixation may not be appropriate for a squint subject. The fourth embodiment relates to the calculation of the interpupillary distance in consideration of such a perspective subject.

  First, the block system in the present embodiment will be described with reference to FIG.

  In the present embodiment, a fixation mode information storage unit 17 is provided in the control system 13. The fixation mode information storage unit 17 stores processing contents in the fixation mode and the fixation release mode.

  The fixation mode refers to, for example, a state in which a fixation target is displayed on the measurement optical path of the refractive power measurement unit 11. By making the subject gaze at the fixation target, the position of the center of the pupil can be kept fixed. On the other hand, the fixation release mode refers to a state in which no fixation target is displayed.

  Based on the input from the operation instruction unit, the control unit 16 reads the corresponding processing content from the fixation mode information storage unit 17. The processing content read from the fixation mode information storage unit 17 is sent to the control unit 16. The control unit 16 performs various controls (display / non-display of the fixation target) based on the information. In the present embodiment, the control unit 16 and the fixation mode information storage unit 17 are collectively referred to as a “fixation mode switching unit”.

  Next, the operation in this embodiment will be described with reference to the flowchart of FIG.

  When the examination by the ophthalmologic apparatus is started, as in the first embodiment, first, the position adjustment between one eye of the subject and the refractive power measuring unit 11 is performed (S41).

  Here, when the subject is a perspective view, a control for switching to the fixation release mode is performed by an input from the operation input unit (S42). In S42, when the subject is not strabismus, control to maintain the fixation mode, or control to switch to the fixation mode when the fixation mode has been canceled in the previous examination is performed.

  Then, both eyes of the subject are simultaneously photographed by the photographing unit 12 (S43), and the interpupillary distance calculation is performed based on the image acquired in S43 (S44).

  By performing the above operations from S41 to S44, it is possible to calculate the interpupillary distance in a state where the fixation mode is set or canceled. Therefore, it is possible to calculate the interpupillary distance with high accuracy even for subjects such as strabismus.

  The series of operations is controlled by the control unit 16.

[Embodiment 5]
9 and 10 relate to a fifth embodiment of the present invention. Note that the configuration of the present embodiment has many parts in common with the first embodiment, and therefore different parts are mainly described.

  In general, pupil sizes differ between day and night. If the pupil size is different, the position of the pupil center also changes. Therefore, there is a difference in the interpupillary distance between day and night. For this reason, there is a demand for dedicated glasses for people who drive a car at night or who work in a dark environment. The fifth embodiment relates to the calculation of the interpupillary distance in consideration of such circumstances.

  First, the control system in the present embodiment will be described with reference to FIG.

  In the present embodiment, the control system 13 has a light / dark mode information storage unit 18. The light / dark mode information storage unit 18 stores processing contents related to control in a bright mode for brightening the field of view and a dark mode for darkening the field of view during photographing by the photographing unit.

  Based on the input from the operation instruction unit, the control unit 16 reads the operation control information in the corresponding mode from the light / dark mode information storage unit 18. The information read from the light / dark mode information storage unit 18 is sent to the control unit 16, and various controls (such as switching to the dark mode) are performed by the control unit 16. In the present embodiment, the control unit 16 and the light / dark mode information storage unit 18 are collectively referred to as a “light / dark mode switching unit”.

  Next, the operation in this embodiment will be described with reference to the flowchart of FIG.

  When the examination by the ophthalmologic apparatus is started, as in the first embodiment, first, position adjustment between one eye of the subject and the refractive power measuring unit 11 is performed (S51).

  Next, an operation for switching to a desired mode is performed by an input from the operation input unit (S52). For example, when it is desired to measure the interpupillary distance when creating night glasses, switching to the dark mode is performed. Specifically, control is performed so as to darken the background of the object that the subject is looking through the refractive power measurement unit 11.

  Then, the imaging unit 12 simultaneously images both eyes of the subject (S53), and calculates the interpupillary distance based on the image acquired in S53 (S54).

  By performing the operations from S51 to S54 described above, the interpupillary distance corresponding to the light / dark mode can be calculated. Therefore, it is possible to calculate the interpupillary distance with high accuracy even when creating glasses for use in a dark environment.

  The series of operations is controlled by the control unit 16.

(Matters common to the first to fourth embodiments)
The configurations of Embodiments 1 to 4 can be combined as appropriate from the viewpoint of calculating the interpupillary distance with high accuracy.

  When performing refractive power measurement or the like, since observation is generally performed in a bright place, it is sufficient that the camera used for the photographing unit 12 has sensitivity in the visible region. On the other hand, in consideration of the possibility of being used in a dark room, a camera sensitive to infrared light may be provided.

  In order to reduce the size of the imaging unit 12 itself and to reduce the space of the ophthalmologic apparatus itself, the imaging unit 12 may be an imaging optical system using a fiber or the like.

  In the present embodiment, the face of the subject is inspected while being fixed to the ophthalmologic apparatus 1. That is, when moving from one eye to observation of the other eye, the main body 2 is moved. On the other hand, there is also an ophthalmologic apparatus that performs binocular measurement by replacing a chin on a plurality of chin rests instead of the main body 2 moving. The present invention can be applied even to such an ophthalmic apparatus.

  Further, it is not necessary to have a single image for simultaneous photographing with both eyes. For example, the left and right eyes are separately photographed by two photographing units whose relative positions are known. Then, the inter-pupil distance can be calculated based on the relative position and the position of the center of the pupil in the images captured by the two imaging units.

2 Main unit 3 Operation unit 3A Operation switch 4 Base unit 5 Remote control 11 Refractive power measurement unit 12 Imaging unit 14 Position adjustment information determination unit 15 Interpupillary distance calculation unit 16 Control unit

Claims (2)

An optical system for examining at least one eye of the subject;
One or more imaging units capable of simultaneously imaging both eyes of the subject;
A position adjustment unit that adjusts the position of the optical system and one eye of the subject;
An interpupillary distance calculating unit that calculates the interpupillary distance of the subject based on the image acquired by the imaging unit;
The optical system, possess a controllable control unit to each of the imaging unit and the inter-pupil distance calculation unit,
After the position adjustment unit performs position adjustment, the control unit causes the photographing unit to perform photographing at the position after the position adjustment,
The pupillary distance calculation unit calculates the interpupillary distance based on the image obtained by photographing performed after the position adjustment, ophthalmology device. A moving unit for moving the optical system;
The control unit moves the optical system to the vicinity of the other eye of the subject by controlling the moving unit based on the interpupillary distance calculated by the interpupillary distance calculating unit. The ophthalmic apparatus according to claim 1.

Images