JP2001314373A - Apparatus for measuring eye - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply constitute an index projection system of a corneal shape measuring mechanism and to improve its operation. SOLUTION: A luminous flux from a light source 38 is incident to a movable optical member 334 via an incident optical member 36. A part of the flux is reflected on an adhering surface of an optical member 35 and the other is incident to a flat plate-like optical member 1. The flux is advanced while reflecting on inner surfaces of the members 1, 34, diffused when the flux is contacted with light diffusing parts 32, 39, reflected at ends of the members 1, 34, and returned. The fluxes diffused in the parts 32, 39 illuminate the cornea of an eye E to be inspected with the parts 32, 39 to become secondary light sources. Since the parts 32, 39 are constituted in a ring-like state at a center of an optical path 01 as a center, the flux reflected on the cornea is imaged by an imaging means 8 to form a ring-like reflected image R on a television monitor 19. This image R is analyzed to obtain the corneal shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eye measuring apparatus for measuring an eye to be examined in an ophthalmic hospital or the like.

[0002]

2. Description of the Related Art There is known an eye measuring apparatus provided with a corneal measuring means for measuring a shape of a cornea including a periphery of an eye to be examined and an eye measuring means such as an eye refraction measurement. An illumination light source is provided behind the ring-shaped index.

In a conventional apparatus for measuring the corneal shape including the periphery of the cornea, a plurality of ring indices are formed on the curved surface of the inner surface of the dome, and the ring is illuminated from behind with a ring-shaped fluorescent lamp or the like.

[0004]

However, in the above-mentioned prior art, there is a problem that the index projection system is large, and the face of the subject is not seen from the examiner, so that the operability of the apparatus is poor. There is also a problem that the index system for projecting onto the cornea requires space in the direction of the optical axis, and the optical system and thus the device are increased in size.

An object of the present invention is to solve the above-mentioned problems,
It is an object of the present invention to provide an eye measuring device having a simple configuration of an index projection system of a corneal shape measuring mechanism and good operability.

[0006]

An eye measuring apparatus according to the present invention for achieving the above object has a corneal measuring means for analyzing a corneal reflection image of an index and measuring a shape of a cornea including a periphery of an eye to be examined. In the eye measurement apparatus, a plurality of flat optical members provided with a light diffusion portion on the surface of the eye to be examined, and an index projection system comprising a light source that illuminates the inside of these flat optical members, I do.

Further, the eye measuring apparatus according to the present invention analyzes a corneal reflection image of an index to measure the shape of the cornea including the periphery of the eye to be inspected, and detects reflected light by projecting a light beam to the eye to be inspected. An eye measurement device having an eye measurement means for measuring the eye by performing a measurement, wherein a flat optical member provided with a light diffusing portion on the surface on the side of the subject's eye and an outer edge of the flat optical member are moved in the optical axis direction. A movable optical member provided with a light diffusing portion on the surface on the side of the subject's eye, and an index projection system including a light source provided outside the movable optical member and illuminating the inside of these optical members; It is characterized by having.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on the illustrated embodiment. FIG. 1 shows a configuration diagram of the first embodiment, and functions as a compound eye measuring apparatus including a corneal shape measuring unit including a peripheral part of the cornea, a corneal curvature measuring unit at a central part of the cornea, and an eye refraction measuring unit. . Optical path O1 in front of eye E
Along with a flat optical member 1, a dichroic mirror 2, which reflects infrared light and transmits other wavelength light, a lens 3, a half mirror 4, which partially reflects and transmits visible light, a lens 6, and a dichroic mirror 2. A dichroic mirror 7 that reflects infrared light and transmits light of other wavelengths, and an imaging unit 8 composed of a video camera are arranged. The output of the imaging means 8 is connected to the calculation means 9 and the television monitor 10.

On the optical path O2 in the reflection direction of the dichroic mirror 2, a lens 11, a mirror 12, a perforated mirror 13, a pupil conjugate diaphragm 14, a lens 15, and an infrared LED conjugate with the fundus are used for measuring refraction. A light source 16 is arranged, and a ring stop 17, a conical prism 18, and a lens 19 conjugate with the pupil are provided on an optical path O3 in the reflection direction of the perforated mirror 13.
Are arranged to reach the dichroic mirror 7. Further, a mirror 20 and a diopter variable lens 2 movable along the optical path O4 are provided on the optical path O4 in the incident direction of the half mirror 4.
1. Fixation targets 22 are arranged.

The flat optical member 1 is a disk made of a transparent acrylic plate, and has a measurement aperture 3 near the optical path O1 at the center.
1 is provided, the inner end face of which is adapted to reflect light. A plurality of ring-shaped light diffusing portions 32 centered on the optical path O1 are formed on the eye E side of the flat optical member 1, and the rings are printed concentrically with white paint or ink. Four light sources 33, which are infrared LEDs, are arranged at oblique 45-degree directions that do not interfere with the optical system behind the flat optical member 1, and are used for illumination for anterior eye observation and for the central cornea. Is also used as an index light source for measuring curvature.

A short cylindrical movable optical member 34 such as acrylic, which is movable in the optical axis direction, is provided on the periphery of the flat optical member 1.
Is attached. At the rear end of the movable optical member 34,
An annular optical member 35 having a triangular cross section is bonded, and a thin film that partially transmits and reflects a light beam is applied to the bonding surface. Further, an annular incident optical member 36 is provided near the rear end of the movable optical member 34, and a number of light sources 38 that emit visible light such as red light fixed to a substrate 37 are disposed behind the annular incident optical member 36. I have. Further, a plurality of ring-shaped light diffusing portions 39 are provided on the inner surface of the movable optical member 34, that is, on the eye E side.
Are formed, and these light diffusion portions 39 are printed with white paint or ink. The front and rear end surfaces of the movable optical member 34 are provided with thin films for reflecting light, and the movable optical member 34 is moved in a direction indicated by a dotted line in a direction indicated by an arrow, that is, in a direction parallel to the optical path O1. The movable optical member 34, the flat optical member 1, and the light source 38 constitute an index projection system of the corneal shape measuring means.

The light beam from the light source 33 passes through the transparent flat optical member 1 and illuminates the anterior segment of the eye E to be examined. The reflected light of the anterior segment is imaged on the imaging means 8 by the anterior segment imaging optical system on the optical path O1 by the lenses 3 and 16. The video signal of the imaging means 8 is displayed on the television monitor 19 as an anterior segment image E 'and observed by the examiner. When measuring the cornea, the optical path O
1, a corneal reflection image by the light source 38 passing through 1, and a ring image 2
An image signal such as 1 is taken into the calculating means 9 and a calculation necessary for the measurement is performed.

A light source 16 for measurement conjugate with the fundus on the optical path O2
Is projected onto the fundus of the eye E via the lens 15, the pupil-conjugated diaphragm 14, the hole of the perforated mirror 13, the mirror 12, the lens 11, and the dichroic mirror 2. The reflected light from the fundus returns along the same optical path O2, is reflected by the perforated mirror 13, and passes through the pupil conjugate ring diaphragm 17, the conical prism 18, the lens 19, and the dichroic mirror 7 to the ring to the imaging means 8 conjugate to the fundus. Receives an image. The ring image is analyzed by the calculating means 9 to measure refraction. The optical path O4 is an optotype, and the fixation optotype 2
2 is presented to the eye E through the diopter variable lens 21.

At the time of refraction measurement or corneal curvature measurement, the movable optical member 34 is housed in a position indicated by a dotted line, that is, in a measurement unit cover (not shown), and thus has the same outer shape as a conventional auto-refractometer and has good operability. Only when measuring the corneal shape, the movable optical member 34 is advanced to the position indicated by the solid line.

Therefore, the light beam from the light source 38 enters the movable optical member 34 via the incident optical member 36, and a part of the light is reflected by the adhesive surface of the optical member 35, and the other is transmitted and transmitted. Incident inside. The light flux is transmitted through these optical members 1, 3
The light diffuser 3 travels while being reflected by the inner surface of
The light is diffused when the light strikes the light sources 2 and 39, and is reflected and returned by the optical members 1 and 34 when reaching the end. Light diffusion unit 3
The light diffused by the light sources 2 and 39 illuminates the cornea of the eye E to be examined, with the light diffusion portions 32 and 39 serving as secondary light sources. Light diffusion unit 3
Since the reference numerals 2 and 39 are formed in a ring shape with the center of the optical path O1 as the center, the light beam reflected by the cornea is imaged by the photographing means 8 and forms a ring-shaped reflection image R on the television monitor 19.

FIG. 2 is a front view of the target projection system of the second embodiment, and FIG. 3 is a plan view. Other parts are the first in FIG.
This is the same as the embodiment. However, in this case, a single-function device that only measures the corneal shape may be used. The center of a transparent horizontally long flat plate-shaped optical member 41 such as an acrylic plate is a measurement opening 42 through which an optical path O1 passes, and the inner end surface thereof is configured to reflect light. On the eye E side of the flat optical member 41,
A plurality of concentric ring-shaped or arc-shaped light diffusion portions 43 are formed around the center of the optical path O1 by silk printing or the like. The left and right outer edges of the flat optical member 41 are linear, and a light source 44, which is a bar-type fluorescent lamp, is disposed in the vicinity thereof in the vertical direction. Further, a flat optical member 45 is provided on both left and right sides via a light source 44 in a direction perpendicular to the flat optical member 41. Further, a light diffusing section 46 is provided inside the flat optical member 45.

Since the upper eyelid easily covers the upper cornea of the subject's eye E, even if the position corresponding to the upper cornea is set as the center of the optical path O1, a reflected image cannot be obtained and measurement cannot be performed.
2 is arranged slightly above the center. Since the eyelids can be measured widely without the eyelids in the left-right direction, the flat optical member 41 is made horizontally long, and the flat optical members 45 are provided on both sides thereof. Therefore, the examiner can easily see the face of the examinee from above the flat optical member 41, and can extend the hand to lift the eyelids of the examinee's eye E.

When the cross section of the flat optical member 45 is illuminated by light emitted forward from the light source 44 and the cross section of the flat optical member 41 is illuminated by light emitted in the horizontal direction, the light is When the light strikes the light diffusing portions 43 and 46, the light diffuses, and a part thereof illuminates the cornea of the eye E, and the light diffusing portions 43 and 46 serve as index light sources. The obtained corneal reflection image is analyzed in the same manner as in the previous embodiment, and the corneal shape of the eye E is determined.

If the width of the flat optical member 41 is set to a width equal to the width of the face and the distance between the eyes, that is, about 23 cm or more, the flat optical member 41 can be moved even when the measuring unit is moved laterally in accordance with the left and right eyes. This is convenient because 45 does not hit the face.

In the multifunction device, the flat optical member 4
5 may be configured to be freely housed similarly to the first embodiment.
In this case, the light source 44 is slightly separated from the flat optical member 41, and the flat optical member 45 is configured to slide in the direction of the optical path O1 between the light sources 44. The device side of the flat optical member 45 is the first optical member. A half mirror may be used as in the embodiment.

In the second embodiment, instead of the light source 44 of the bar-shaped fluorescent lamp, a large number of LEDs may be arranged linearly adjacent to each other, and the flat optical members 41 and 45 are joined at the ends. It can also be integrated. Further, the flat optical member 45 may be omitted.

[0022]

As described above, in the eye measuring apparatus according to the present invention, a corneal shape measurement index system can be easily constituted by a flat optical member.

Further, by providing a movable optical member,
At the time of eye measurement other than corneal shape measurement, the corneal shape measurement optotype system does not interfere, and operability is good.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an eye measurement device according to a first embodiment.

FIG. 2 is a front view of a target projection system according to a second embodiment.

FIG. 3 is a plan view of a target projection system according to a second embodiment.

[Description of Signs] 1, 41, 45 Plate-shaped optical member 8 Imaging means 9 Calculation means 10 TV monitor 32, 39, 43, 46 Light diffusion unit 33, 39, 44 Light source 34 Movable optical member

Claims (2)

[Claims] 1. An eye measuring apparatus comprising a corneal measuring means for analyzing a corneal reflection image of an index and measuring a shape of a cornea including a periphery of an eye to be examined, wherein a plurality of light diffusing portions are provided on a surface on the side of the eye to be examined. An eye measuring apparatus comprising: a flat optical member; and an index projection system including a light source for illuminating the inside of the flat optical member. 2. A corneal measuring means for analyzing a corneal reflection image of an index to measure a shape of a cornea including a periphery of an eye to be inspected, and an eye measuring means for projecting a light beam to the eye to be inspected and detecting reflected light to perform eye measurement. In the eye measurement device provided with, a flat optical member provided with a light diffusing portion on the surface of the eye to be inspected, and configured to move in the optical axis direction at the outer edge of the flat optical member, the surface of the eye to be inspected An eye measurement system comprising: a movable optical member provided with a light diffusing portion; and an index projection system including a light source provided outside the flat optical member and the movable optical member and illuminating the inside of the optical member. apparatus.