JPH0614883A - Eye refraction meter - Google Patents

Abstract

PURPOSE:To measure an eye refraction value by discovering the part of light flux transmitted through the pupil. CONSTITUTION:An opening iris 3, hole opening mirror 4, objective lens 5 and dichroic mirror 6 are arranged on an optical path 01 from a light source 1 to the eye E to be examined, and an opening iris 8 provided with six openings and a separation prism 10 composed of six wedge prisms are arranged near an optical axis on an optical path 02 in the reflecting direction of the hole opening mirror 4. A television camera 15 is arranged on an optical path 03 in the reflecting direction of the dichroic mirror 6, and the output of the television camera 15 is connected to a television monitor 16. In this case, six reflected beams from the eye ground Er obtained by the television camera 15 are used as marks M1 and displayed on the television monitor 16 while being overlapped with front eye part images obtained by an illumination light source 7, and the light flux from the light source 1 is made eccentric and passed through the pupil Ep so that these marks M1 can appear on the television monitor 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eye refractometer used in eye clinics and eyeglass stores.

[0002]

2. Description of the Related Art The following are known conventional measuring methods for an eye refractometer. (1) A method of measuring by aligning the optical axis with the center of the pupil. (2) A method disclosed in Japanese Patent Laid-Open No. 62-5594, in which specific horizontal and vertical radial line target images and anterior ocular segment images are imaged on the same monitor for measurement. (3) The fundus image and the anterior segment image disclosed in JP-A-43-60633 are time-divided and captured on a monitor.
The method of dividing and projecting.

[0003]

In the above-mentioned conventional example (1), measurement may not be possible because the light beam cannot pass through the pupil due to opacity of the transmissive body due to cataracts, small pupil, etc. In this case, an error is simply displayed. It is only done. However, even in such a case, it is often possible to measure the light flux by eccentricity through the pupil, but this is not a general method.

Further, in the above-mentioned conventional example (2), the measurement is inconvenient unless all the images of the radial lines used for the measurement are prepared.

In the above-mentioned conventional example (3), it is necessary to store an image, which complicates the apparatus.

An object of the present invention is to provide an eye refractometer capable of measuring eye refraction even when the eye to be inspected has a opaque translucent body due to cataract or the like, or has a small pupil.

[0007]

A first ocular refractometer for achieving the above object comprises an image pickup means for picking up an anterior segment image, a display means for displaying an output of the image pickup means, and a fundus on the fundus. It has a projection optical system for projecting a light flux and a light receiving means for receiving the fundus reflected light flux including at least three radial lines, and performs alignment by the anterior segment image projected on the display means, and the fundus reflected light flux. In the eye refractometer for obtaining the eye refraction value from the position, the mark indicating the light receiving state of the fundus reflected light is displayed on the display means in an overlapping manner with the anterior segment image.

The second ocular refractometer projects the light flux from the first region of the pupil onto the fundus by the image pickup means for picking up the anterior segment image, the display means for displaying the output of the image pickup means, and A two-dimensional optical position detector receives a light beam including at least three radial lines from a second region different from the first region, and an eye refractometer that obtains an eye refraction value from these light beam positions is reflected by the detector. It is characterized in that a mark indicating a light receiving state is displayed together with the anterior segment image on different parts of the display means.

[0009]

In the first eye refractometer having the above-described structure, the mark indicating the light receiving state of the reflected light from the fundus is displayed on the display means by superimposing it on the image of the anterior segment of the eye, and the measurement light flux is displayed so that this mark appears. Eccentricity is transmitted through the pupil.

The second ocular refractometer displays a mark showing the light receiving state of the reflected light from the fundus together with the anterior segment image on different parts of the display means, and decenters the measurement light beam so that this mark appears. Let the pupil penetrate.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on the illustrated embodiments. FIG. 1 is a configuration diagram of the first embodiment, in which a lens 2, an aperture stop 3, and an aperture stop 3 are provided on an optical path 01 from a light source 1 to an eye E to be inspected.
A perforated mirror 4, an objective lens 5, and a dichroic mirror 6 are arranged, and a plurality of illumination light sources 7 are provided in front of the eye E to be examined. On the optical path 02 in the reflection direction of the perforated mirror 4, a 6-hole aperture stop 8 having 6 apertures around the optical axis,
A lens 9, a separation prism 10 composed of six wedge prisms, and a dichroic mirror 11 are arranged. A lens 12, a mirror 13, a lens 14, a dichroic mirror 11, and a television camera 15 having an image sensor 15a are arranged on the optical path 03 in the reflection direction of the dichroic mirror 6, and the output of the television camera 15 is output to a television monitor 16. It is connected. Here, the light source 1 is conjugated with the fundus Er, and the aperture stops 3 and 6-aperture aperture 8 are conjugated with the pupil Ep.

The light flux from the light source 1 passes through the lens 2, the aperture stop 3, the perforated mirror 4, the objective lens 5 and the dichroic mirror 6 to illuminate the fundus Er in a spot shape. Fundus Er
The reflected light from exits the pupil Ep and goes right in the same optical path,
The light is reflected by the perforated mirror 4, passes through the 6-hole aperture stop 8, the lens 9, and the separating prism 10, and then is reflected by the dichroic mirror 11, and the image pickup device 15 a of the television camera 15.
To the top. The reflected image obtained by the image sensor 15a apparently passes through the pupil Ep as shown in FIG. 2 (a), and six small circles as shown in FIG. 2 (b) are formed on the image sensor 15a. A bright spot image Pa of the mold is formed. Then, a total of 7 small circles corresponding to the 6 bright spot images Pa and the optical axis of the light source 1 are electrically or optically combined as an alignment mark M1 and displayed on the television monitor 16.

The luminous flux from the illumination light source 7 is emitted from the anterior segment Ef.
And the reflected light from the anterior segment Ef is reflected by the dichroic mirror 6, and the lens 12, the mirror 13, the lens 1
4, TV camera 1 through dichroic mirror 11
The anterior ocular segment image Pf is formed on the image pickup device 15a of No. 5. Then, the combined alignment mark M1 and anterior segment image Pf are
It is superimposed on the TV monitor 16 and displayed. As shown in FIG. 1, when combining both images, it is preferable that the illumination light source 7 be turned on weakly so that both the alignment mark M1 and the anterior segment image Pf can be seen.

While examining the television monitor 16, the examiner aligns the alignment mark M1 with the anterior segment image Pf, and obtains a refraction value from the positional relationship between the pupil Ep and the bright spot image Pa by a computer or the like not shown.

2 (a) to 7 (a) show the relationship between the pupil Ep of the television monitor 16 and the alignment mark M1 in various states, and FIGS. 2 (b) to 7 (b) show the image pickup device 15a. The upper bright spot image Pa is shown.

In the case of the opacity or the pupil Ep which is not a small pupil, when the optical axis of the light source 1 is aligned with the center of the pupil Ep as shown in FIG. 2 (a), it is seen from the fundus Er as shown in FIG. 2 (b). The reflected light of
Six small circular bright spot images Pa are formed in the vicinity of the perforated mirror 4, and the alignment mark M1 overlaps the pupil Ep on the television monitor 16 as shown in FIG. Optical axis center O and bright spot image
The refraction value is obtained from the distance between the respective bright points of Pa by a computer or the like not shown.

When the eye E has opacity in the pupil Ep,
Turbidity does not appear in the observation optical system of the anterior segment Ef, and if the optical axis of the light source 1 is centered as in the conventional case, the incident light flux from the light source 1 may not be able to pass through the pupil Ep, and the bright spot image Pa Is not obtained, and the alignment mark M1 is not displayed on the TV monitor 16. In such a case, the examiner looks at the television monitor 16 and adjusts so that the alignment mark M1 appears.

For example, as shown in FIG. 3 (a), when the right half of the pupil Ep is opaque and is an opaque region,
The examiner operates so that the alignment mark M1 appears on the television monitor 16. If three bright points appear in addition to the center point as shown in FIG. 3 (b), the refractive powers in the three radial directions can be known. Therefore, the refraction value including astigmatism can be calculated.

In cataract, the central part of the pupil Ep may become cloudy as shown in FIG. 4 (a). Similarly, when the alignment mark M1 appears in addition to the center point by operating the device, based on the distance between the center O of the optical axis and the alignment mark M1 and the distance between the two alignment marks M1, Astigmatism and refraction values are calculated by a computer or the like not shown.

Then, as shown in FIG.
Is a small pupil, and when the pupil Ep is sufficiently smaller than the reflected light from the fundus Er, if the center of the pupil Ep and the optical axis of the light source 1 are aligned with each other, as in the case of turbidity, the television monitor 16 The alignment mark M1 will not appear at all.
Therefore, the examiner makes an adjustment while looking at the television monitor 16 so that at least one alignment mark M1 appears in addition to the center point.

When two or more alignment marks M1 appear, the refraction value can be obtained by the above-mentioned calculation method. If only one alignment mark M1 appears in addition to the center point as shown in FIG. 5 (a), one alignment mark M1
Make the first eye refraction measurement, adjusting so that M1 appears clearly. Next, make adjustments so that another alignment mark M1 appears as shown in FIG. 6, and perform the second measurement,
From the position of these two alignment marks M1, see FIG.
The eye refraction value and the astigmatism measurement value can be obtained by the same calculation method as in the case where the two bright spots of 1 appear. Actually 1
When only one alignment mark M1 is recognized, it is preferable to perform the measurement twice and obtain the eye refraction value and the astigmatism.

FIG. 7 is an optical layout diagram of the second embodiment.
On the optical path 04 from the light source 17 to the subject's eye E, the ring diaphragm 18, the lens 19, the ring diaphragm 20, and the perforated mirror 2 are provided.
1, an objective lens 22, and a dichroic mirror 23 are arranged. Further, a television camera 25 for observing the anterior segment having a lens 24 and an image pickup device 25a is arranged on the optical path 05 in the reflection direction of the dichroic mirror 23, and the optical path 06 in the opposite direction of the eye E of the perforated mirror 21 is arranged. A television camera 28 for fundus observation having an aperture stop 26, a lens 27, and an image pickup device 28a is arranged above. Further, the outputs of the television cameras 25 and 28 are connected to a signal processor 29, and the signal processor 29 is connected to an image selection switch 30 and a television monitor 31. Here, the ring diaphragm 18 is conjugated with the fundus Er, and the ring diaphragm 20 and the aperture diaphragm 26 are conjugated with the pupil Ep.

The light beam from the light source 17 passes through the ring diaphragm 18, the lens 19, the ring diaphragm 20, the perforated mirror 21, the objective lens 22 and the dichroic mirror 23 to reach the fundus Er of the eye E to be examined. The reflected light from the fundus Er travels to the right in the same optical path and is directed to the dichroic mirror 23 and the objective lens 22.
Through the aperture stop 21 and reflected by the perforated mirror 21.
6, the lens 27, the image pickup device 2 of the TV camera 28
A ring image Pb is formed on 8a. This ring image Pb serves as an alignment mark M2 by electrical or optical synthesis,
The image is displayed on the television monitor 31 as shown in FIG.

A light beam from an anterior eye part illumination light source (not shown) illuminates the anterior eye part Ef, and reflected light from the anterior eye part Ef passes through the dichroic mirror 23 and the lens 24, and the television camera 2
The anterior segment image Pf is formed on the image pickup device 25a of No. 5. The image of the anterior segment image Pf and the alignment mark M2 are processed by the signal processor 29.
7 shows only the anterior segment image Pf on the television monitor 31 as shown in FIG. 7, or only the alignment mark M2 as shown in FIG. 8, or the anterior segment image Pf as shown in FIG. A composite image of the alignment mark M2 is displayed, and the selection / switching of these images is performed by the image selection switch 30.

The examiner aligns the device so that the alignment mark M2 appears on the television monitor 31, and analyzes the shape of the ring image Pb by the computer to obtain the refraction value. For example, when there is partial turbidity and only a partial ring image is obtained as shown in FIG.
As shown in (b), three radial lines S1, S2, S3 passing through the center O of the optical axis
The refraction value can be calculated by obtaining an elliptic expression from the intersection of the ring image Pb and the ring image.

FIG. 11 is a block diagram of the third embodiment, in which a lens 33, a lens 33, are provided on the optical path 07 from the light source 32 to the eye E to be examined.
An aperture stop 34, a perforated mirror 35, an objective lens 36, and a dichroic mirror 37 are arranged, and the lens 3 is provided on the optical path 08 in the reflection direction of the dichroic mirror 37.
8. A television camera 39 for observing the anterior segment having the image pickup element 39a is arranged. Further, on the optical path 09 in the reflection direction of the perforated mirror 35, a 6-hole aperture stop 40 having six holes circumferentially, a lens 41, a separation prism 42 composed of six wedge prisms, and an image sensor. A television camera 43 for observing the fundus having 43a is arranged. Both outputs of the television cameras 39 and 43 are connected to a television monitor 45 via a signal processor 44. The aperture stop 3
The 4- and 6-hole aperture stop 40 is conjugate with the pupil Ep.

A light beam from the light source 32 passes through a lens 33, an aperture stop 34, a perforated mirror 35, an objective lens 36, and a dichroic mirror 37 to illuminate the fundus Er of the eye E to be examined in a spot shape. The reflected light from the fundus Er goes right in the same optical path, is reflected by the perforated mirror 35, and has a 6-hole aperture stop 40,
The television camera 4 passes through the lens 41 and the separation prism 42.
An image is formed as a bright spot image Pc on the third image pickup element 43a as shown in FIG. If the subject's eye E is normal, six small circular bright spot images Pc are formed on the image sensor 43a, and if the right half of the pupil Ep is cloudy, as shown in FIG. The number of bright spots Pc decreases.

An anterior ocular segment is provided by an illumination light source (not shown).
When Ef is illuminated, the reflected light from the anterior segment Ef passes through the dichroic mirror 37 and the image pickup device 39a of the television camera 39.
Image on top. The image on the image sensor 39a is shown in FIG.
As shown in 1, the image is displayed as the anterior segment Ef on the area R1 of the television monitor 45.

The bright spot image Pc on the image pickup element 43a of the television camera 43 is a signal processor 4 including a pattern generator and the like.
It is electrically or optically combined via 4 and displayed as an alignment mark M3 on the region R2 of the television monitor 45. If the alignment is correctly performed by a normal eye, six spot lights can be obtained as the alignment mark M3.

FIG. 14 shows an alignment mark M4 consisting of an incident light beam L1 and an outgoing light beam L2. When the pupil Ep has turbidity,
A bright spot image Pc as shown in FIG. 15 is obtained by the image sensor 43a. An alignment mark M3 that approximates the state of the bright spot image Pc by the signal processor 44 is created and displayed in the area R2 of the television monitor 45 as shown in FIG.

The region R1 of the television monitor 45 has an anterior segment image.
Pf and alignment mark M4 are superimposed and displayed. From the states of these alignment marks M3 and M4, it can be seen that if the alignment mark M4 is slightly eccentric with respect to the anterior segment image Pf, the outgoing light beam L2 can partially pass through the pupil Ep. The measurement result D by the signal processor 44 is displayed at the bottom of the screen.

The light source 32 may emit light manually or automatically at regular intervals, for example, about twice per second, and the alignment mark M3 and the measurement result D may be displayed in synchronization with each light emission. The examiner adjusts the device so that the alignment mark M3 appears best, and reads the measurement result D at that time.

The television camera for observing the anterior segment and the television camera for observing the fundus may be used together as in the first embodiment.

In the above example, the fundus Er was illuminated in a spot shape, but the fundus Er may be illuminated in a ring shape as in the second embodiment. In this case, the light receiving state is aligned as shown in FIG. The mark M5 can be displayed on the area R2 of the TV monitor. In this alignment mark M5, the small circle in the center indicates the light beam L2 emitted from the pupil, and the outer ring light beam indicates the incident light beam L1. Here, half of the incident light beam is received on the CCD used as the image sensor. Is shown.

[0035]

As described above, according to the first eye refractometer, the anterior segment image and the mark indicating the light receiving state of the measurement light beam are overlapped and displayed on the display means, whereby the eccentricity of the measurement light beam is deviated. Since it is easy to know how to do so, it is possible to partially find the transparent portion of the light-transmissive body of the eye to be measured.

Further, according to the second eye refractometer, a mark indicating the light receiving state of the measurement light beam is displayed on a different portion of the same screen separately from the anterior segment image, so that the transmissive portion of the translucent body is searched for. It is easy to do and the operability is improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment.

FIG. 2 is an explanatory diagram of reflected light from a pupil and a fundus in the case of a normal pupil.

FIG. 3 is an explanatory diagram of reflected light from a pupil and a fundus when the right half is cloudy.

FIG. 4 is an explanatory diagram of reflected light from a pupil and a fundus when the central portion is cloudy.

FIG. 5 is an explanatory diagram of reflected light from a pupil and a fundus in the case of a small pupil.

FIG. 6 is an explanatory diagram of reflected light from a pupil and a fundus in the case of a small pupil.

FIG. 7 is a configuration diagram of a second embodiment.

FIG. 8 is an explanatory diagram of an alignment mark on a television monitor.

FIG. 9 is an explanatory diagram of a combined image of an alignment mark and an anterior segment on a television monitor.

FIG. 10 is an explanatory diagram of light reflected from the pupil and the fundus of the alignment mark.

FIG. 11 is a configuration diagram of a third embodiment.

FIG. 12 is an explanatory diagram of a bright spot image on an image sensor in the case of a normal pupil.

FIG. 13 is an explanatory diagram of a bright spot image on an image sensor in the case of a pupil having an opaque portion in the right half.

FIG. 14 is an explanatory diagram of a relationship between a pupil and an alignment mark.

FIG. 15 is an explanatory diagram of a monitor during measurement.

FIG. 16 is an explanatory diagram of a monitor during measurement.

FIG. 17 is an explanatory diagram of an alignment mark according to a fourth embodiment.

[Explanation of symbols]

 1, 17, 32 Light source 3, 34 Aperture stop 4, 21, 35 Perforated mirror 5, 33, 36 Objective lens 6, 11, 23, 37 Dichroic mirror 8, 40 6-hole aperture stop 10, 42 Separation prism 15, 25 , 28, 39, 43 TV camera 16, 31, 45 TV monitor 18 Ring diaphragm 29, 44 Signal processor

Claims (2)

[Claims] 1. An image pickup unit for picking up an anterior segment image, a display unit for displaying an output of the image pickup unit, a projection optical system for projecting a light beam on a fundus, and a fundus reflected light beam including at least three radial lines. In the eye refractometer for determining the eye refraction value from the position of the fundus reflected light beam, the light reception state of the fundus reflected light is determined by the anterior segment image projected on the display means. An eye refractometer, wherein the mark shown is displayed on the display means so as to be superimposed on the anterior segment image. 2. An image pickup means for picking up an anterior segment image, a display means for displaying an output of the image pickup means, and a light beam projected from a first region of a pupil onto a fundus of the eye, and a first light region different from the first region. In the eye refractometer, which receives a light flux including at least three radial lines from the area No. 2 by a two-dimensional optical position detector and obtains an eye refraction value from those light flux positions, a mark indicating a light reception state of reflected light by the detector. Are displayed on different parts of the display means together with the anterior segment image, respectively.