JP2007159850A - Ophthalmological measuring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ophthalmological measuring apparatus for achieving miniaturization by making the optical system to have a very simple structures relating to an index optical system and a fundus reflectance index light-receiving optical system, and by reducing the number of parts. <P>SOLUTION: The ophthalmological measuring apparatus is equipped with a fundus index projective optical system, a fundus reflectance index light-receiving optical system for inducing the index image reflected at the fundus to a photoelectric conversion means through a spectroscopic means, a visual index optical system for providing the visual index and fixing the index to a tested eye through the spectroscopic means, and the photoelectric conversion means, the visual index, and the spectroscopic means are composed together so as to be movable in the optical axis direction as a spectroscopic unit, and the optical path in the fundus reflective visual index light-receiving optical system is in common with the optical path in the visual index optical system from the tested eye in the spectroscopic means. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ophthalmologic measurement apparatus having a function of measuring the eye refractive power of an eye to be examined, such as a refractometer and a refractometer.

  As shown in FIG. 1, the ophthalmologic measuring apparatus that measures the eye refractive power of the eye 101 includes an anterior ocular segment observation optical system 120, a visual target optical system 150 that presents a visual target 152 to the eye 101 to be examined, A reflex projector 110 that projects fundus index light onto the fundus 103 and a light receiving optical system 130 that receives on the CCD sensor 132 a fundus index image reflected by the fundus 103 are provided. These optical systems are incorporated in the apparatus as separate dedicated optical systems.

  Individually configuring the target optical system 150 and the light receiving optical system 130 as dedicated optical systems requires optical components such as a reflection mirror 148 and an imaging lens in each optical system, and thus is very expensive. There is a problem of becoming a thing.

  In addition, when the target optical system 150 has a cloud function in which the eye 101 to be adjusted is in a state of adjustment relaxation in which the eye 101 is sufficiently relaxed and the target eye 101 in the adjustment relaxation state fixes the target 152, the cloud state Since the target optical system 150 is provided with a target drive mechanism for moving the target 152 to form the target, the target optical system 150 becomes complicated and there is a problem that the apparatus becomes large (for example, Patent Documents). 1).

JP 57-25834 A

  Therefore, the technical problem to be solved by the present invention is that the optical system related to the target optical system and the fundus reflection index light receiving optical system has a very simple configuration, and the miniaturization is realized by reducing the number of parts used. It is to provide an ophthalmic measurement device.

Means for solving the problems and their actions and effects

  In order to solve the above technical problem, an ophthalmic measurement apparatus according to the present invention has the following features.

That is, the ophthalmic measurement apparatus according to the present invention is
A fundus index projection optical system for projecting an index for measuring the degree of eye refraction on the fundus of the eye to be examined;
A fundus reflection index light receiving optical system that guides the index image reflected from the fundus to the photoelectric conversion means via the spectroscopic means;
A target optical system for presenting a target for fixation on the eye to be examined via the spectroscopic means;
An ophthalmic measurement device comprising:
The photoelectric conversion means, the target, and the spectroscopic means are configured to be movable in the direction of the optical axis integrally as a spectroscopic unit,
The optical path from the eye to be analyzed to the spectroscopic means in the fundus reflection index light receiving optical system and the optical path from the eye to the spectroscopic means in the target optical system are made common.

  According to the ophthalmologic measurement apparatus having the above configuration, the optical path from the eye to be inspected to the spectroscopic means is made common in each of the fundus reflection index light receiving optical system and the target optical system. Therefore, the conventional ophthalmic measuring apparatus is composed of two dedicated optical systems, ie, a fundus reflection index light receiving optical system and a target optical system, whereas the ophthalmic measuring apparatus of the present invention is from the eye to the spectroscopic means. Since the optical system is shared, the optical system is very simple, the number of parts used is reduced, and the miniaturization can be realized.

  The optical path length from the spectroscopic means to the target is longer than the optical path length from the spectroscopic means to the photoelectric conversion means, and the target is measured in a cloudy state.

  According to the above configuration, the spectroscopic unit is moved from a state in which the target is in focus but the photoelectric conversion means is not in focus to a distance position where the eye's adjustment force does not work, so that the photoelectric conversion means While it is positioned at the in-focus position where it is in focus, it is positioned in a state where the visual target is not in focus, that is, in the cloud fog position, so the eye refraction degree of the eye to be examined is accurately measured.

  Hereinafter, an embodiment of an ophthalmologic measurement apparatus according to the present invention will be described in detail with reference to FIGS.

  FIG. 2 is an explanatory diagram for explaining a measurement optical system of an eye refractive power measurement apparatus according to an embodiment of the present invention, and FIG. 3 shows that the eye to be examined is in a clear vision state in the ophthalmic measurement apparatus of FIG. FIG. 4 is a diagram showing that the visual target is in a cloudy fog state in the ophthalmologic measurement apparatus of FIG. 2, and FIG. 5 is a flowchart when measuring the eye refraction degree.

  As shown in FIG. 2, the measurement optical system of the eye refractive power measuring apparatus is an anterior ocular segment observation optical system that forms an optical axis 7 and an anterior segment image of the subject eye 1 on a CCD sensor 22 as a photoelectric detector. A fundus index for forming an image of a fundus index image reflected on the fundus 3 on a CCD sensor 32 as a photoelectric detector, a system 20, a reflex projector 10 for projecting reflex measurement index light onto the fundus 3 of the subject eye 1 An image receiving optical system 30 and a visual target optical system 50 for presenting a visual target 52 to the eye 1 to be examined are provided.

  An illumination light source (not shown) is provided in the vicinity of the eyepiece 28, and the anterior eye portion of the eye 1 is illuminated by the illumination light emitted from the illumination light source, and the anterior eye portion of the eye 1 is observed. . In the anterior ocular segment observation optical system 20, the anterior ocular segment image is guided onto the CCD sensor 22 through the eyepiece lens 28, the half mirror 26, and the focusing lens 24.

  The fundus index light projection optical system includes a reflex projector 10, a perforated mirror 46, a half mirror 26, and an eyepiece 28. The reflex projector 10 includes a fundus index light projection light source, a first mask, a projection lens, and a second mask. Although the fundus index light projection light source, the first mask, the projection lens, and the second mask are all not shown, the second mask is disposed at a position conjugate to the cornea with respect to the eyepiece lens 28. In the reflex projector 10, the beam light from the fundus index light projection light source set to the prescribed incident angle and height with respect to the optical axis 7 is sequentially supplied from the light source side to the first mask, the projection lens, and the first light source. By passing through the two masks, the index light for ref measurement is emitted. The reflex measurement index light is projected onto the eye 1 through the perforated mirror 46, the half mirror 26, and the eyepiece lens 28, and a fundus index image reflected by the fundus 3 of the eye 1 is formed.

  In the fundus index image light receiving optical system 30, in order from the eye 1 to be examined, an eyepiece 28, a half mirror 26, a perforated mirror 46, an imaging lens 42, a half mirror 44 as a spectroscopic means, and a CCD as a photoelectric conversion means. A sensor 32 is arranged. As will be described later, the half mirror 44 and the CCD sensor 32 are attached to an integrated spectroscopic unit 40 including a visual target 52, and are configured to be movable back and forth with respect to the optical axis 7. Has been. The spectroscopic unit 40 is provided with driving means for translating the spectroscopic unit 40 along the optical axis 7.

  In the fundus index image receiving optical system 30, the perforated mirror 46 is disposed at a position conjugate with the cornea with respect to the eyepiece lens 28. The fundus reflection image reflected by the fundus 3 is guided to the through hole of the perforated mirror 46, and the light of the fundus index image that has passed through the perforated mirror 46 is imaged on the CCD sensor 32 by the imaging lens 42.

  In the target optical system 50, an eyepiece 28, a half mirror 26, a perforated mirror 46, an imaging lens 42, a half mirror 44 as a spectroscopic unit, and a target 52 are arranged in this order from the eye 1 side. .

  The spectroscopic unit 40 includes a housing including a half mirror 44, a CCD sensor 32, and a visual target 52. The spectroscopic unit 40 is configured to guide light from the subject eye 1 to the CCD sensor 32 via the half mirror 44 serving as spectroscopic means and to present the target 52 to the subject eye 1. The spectroscopic unit 40 is moved in the optical axis direction by various known driving means. Therefore, the half mirror 44, the CCD sensor 32, and the visual target 52 housed in the housing move integrally. As the drive mechanism, for example, a mechanism in which a rack is attached to the spectroscopic unit 40 so that the spectroscopic unit 40 slides in parallel with the optical axis 7 and a pinion is attached to the rotation shaft of the motor can be used.

  In the ophthalmologic measurement apparatus of the present invention, the optical path from the eye 1 to the half mirror 44 in the fundus reflection index light receiving optical system 30 and the optical path from the eye 1 to the CCD sensor 32 in the target optical system 50 are made common. Yes. For example, the optical path length from the half mirror 44 to the target 52 and the optical path length from the half mirror 44 to the CCD sensor 32 may be substantially equal.

  Therefore, the ophthalmic measuring apparatus according to the present invention has a very simple optical system since the optical system from the eye 1 to the half mirror 26 is shared, and the number of components used is also small. Therefore, miniaturization is realized.

  The positional relationship between the CCD sensor 32 in the fundus reflection index light receiving optical system 30 and the target 52 in the target optical system 50 will be described with reference to FIGS.

  FIG. 3 shows that the eye 1 to be examined is in a clear vision state. In the spectroscopic unit 40, the CCD sensor 32 is arranged at a position of −1 to −2 diopters from a position in focus with respect to the fundus. In addition, the visual target 52 is disposed at a distance position, that is, a clear vision position (a position focused on the fundus). Therefore, the optical path length from the half mirror 44 to the visual target 52 is longer than the optical path length from the half mirror 44 to the CCD sensor 32.

  FIG. 4 shows a state in which the eye refractive power of the eye 1 to be examined is measured, and shows that the visual target 52 is in a cloudy state. 4, compared with FIG. 3, the CCD sensor 32 is in a position in focus with respect to the fundus and the visual target 52 is in a position of +1 to +2 diopters from the position in focus with respect to the fundus. As described above, the spectroscopic unit 40 is moved along the optical axis 7 to the opposite side of the eye 1 to be examined. Accordingly, FIG. 4 shows that the CCD sensor 32 is in focus and the optical path length from the half mirror 44 to the visual target 52 is maintained while the optical path length from the half mirror 44 to the CCD sensor 32 is maintained. The mark 52 is in a cloudy state.

  Next, a method for measuring the eye refraction degree of the eye 1 to be examined will be described with reference to FIG.

  In the ophthalmologic measurement apparatus shown in FIG. 2, measurement of the eye refractive index starts at step # 100. At the beginning of the measurement, the optical system of the ophthalmologic measurement apparatus is positioned at an initial position based on the in-focus position of the normal eye.

  In step # 110, in order to obtain advance information on how much adjustment power the subject eye 1 has, the subject looks inside the apparatus through the eyepiece lens 26, and the subject eye 1 passes through the eyepiece lens 26 to the target 52. In a state where the eye is fixed, temporary measurement of the eye refractive index is started. After the temporary measurement, in step # 120, the approximate eye refraction degree of the eye 1 to be examined is calculated.

  In step # 130, the spectroscopic unit 40 is moved by a predetermined amount along the optical axis 7 based on the above-mentioned provisional refraction degree, and as shown in FIG. The spectroscopic unit 40 is positioned.

  In step # 140, the spectroscopic unit 40 is moved along the optical axis 7 by, for example, +1.5 diopters from a position focused on the fundus, and the target 52 as shown in FIG. 4 is in a cloudy state. The spectroscopic unit 40 is positioned at the cloud fog position.

  At this time, since the fundus index image is focused on the CCD sensor 32, the main measurement of the eye refractive index starts in Step # 150. After this measurement, in step # 160, an accurate eye refraction degree of the eye 1 to be examined is calculated.

  After the measurement result of the eye refraction degree is displayed on the display display in step # 170, a series of measurement is completed in step # 180.

  Although not shown, the optical path length from the half mirror 44 to the target 52 and the optical path length from the half mirror 44 to the CCD sensor 32 can be configured to be equal. In such a configuration, before the eye refractive power of the eye 1 to be measured is measured, the CCD sensor 32 is in a focused position with respect to the fundus even when the eye 1 is in the clear vision state. When measuring the eye refractive power of the eye 1 to be examined, the spectroscopic unit 40 is moved along the optical axis 7 from the position focused on the fundus to the opposite side of the eye 1 with a size of about +1 to +2 diopters. . As a result, the visual target 52 and the CCD sensor 32 are located at positions of +1 to +2 diopters from the position focused on the fundus. Therefore, the visual target 52 is in the cloudy state. On the other hand, the CCD sensor 32 is in an out-of-focus position, and the fundus index image formed on the CCD sensor 32 is slightly out of focus, but the fundus index image is slightly out of focus. Can be used for calculation of eye refractive power.

  In addition, although the said ophthalmologic measuring apparatus demonstrated the eye refractive power measuring apparatus which measures the eye refractive power of the eye 1 to be examined, the eye refraction mentioned above is a well-known corneal shape measuring means for measuring the corneal shape of the eye 1 to be examined. A refractor keratometer that measures both the eye refractive power and the corneal shape can also be provided in the force measuring device.

It is a figure explaining the optical system of the ophthalmic measurement apparatus concerning a prior art. It is a figure explaining the optical system of the ophthalmic measuring device concerning one embodiment of the present invention. It is a figure which shows that the to-be-tested eye is in a clear vision state in the ophthalmic measurement apparatus shown in FIG. It is a figure which shows that a target is in a cloudy fog state in the ophthalmologic measurement apparatus shown in FIG. It is a flowchart at the time of measuring the eye refraction degree in the ophthalmologic measurement apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Eye to be examined 3 Fundus 7 Optical axis 10 Ref light projection part 20 Anterior eye part observation optical system 22 CCD sensor (photoelectric conversion means)
24 imaging lens 26 half mirror 28 eyepiece 30 fundus index image light receiving optical system 32 CCD sensor (photoelectric conversion means)
40 Spectroscopic unit 42 Imaging lens 44 Half mirror (spectral means)
46 Hole mirror 50 Target optical system 52 Target

Claims (2)

A fundus index projection optical system for projecting an index for measuring the degree of eye refraction on the fundus of the eye to be examined;
A fundus reflection index light receiving optical system that guides the index image reflected from the fundus to the photoelectric conversion means via the spectroscopic means;
A target optical system for presenting a target for fixation on the eye to be examined via the spectroscopic means;
An ophthalmic measurement device comprising:
The photoelectric conversion means, the target, and the spectroscopic means are configured to be movable in the direction of the optical axis integrally as a spectroscopic unit,
An ophthalmologic measurement apparatus characterized in that an optical path from a subject eye to a spectroscopic means in the fundus reflection index light receiving optical system and an optical path from the subject eye to the spectroscopic means in a target optical system are made common.   The ophthalmologic according to claim 1, wherein the optical path length from the spectroscopic means to the target is longer than the optical path length from the spectroscopic means to the photoelectric conversion means, and the target is measured in a cloudy state. measuring device.

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