JP3311054B2 - Subjective optometry device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a subjective optometric apparatus used for measuring an eye refractive power, and more particularly to a subjective optometric apparatus which can advantageously prevent or correct a measurement error caused by a distance difference due to a positional shift of an eye to be examined. The present invention relates to an optometry apparatus.

[0002]

2. Description of the Related Art Conventionally, as a kind of a device for measuring an eye refractive power for inspection of refraction of an eyeball or the like, as shown in FIG. A subjective optometric apparatus is known which includes a window 4 and allows an eye 6 to be examined to visually recognize an index 12 from behind the observation window 4 through the lens 2.

In such a subjective optometric apparatus, the distance (sighting distance) L between the rear surface of the lens (reference position) and the apex of the cornea of the eye to be examined is a certain value (for example, 1).
Under the precondition that the eye refractive power is 2 mm), the eye refractive power is measured. Therefore, at the time of the examination, it is necessary to confirm whether or not the eye 6 to be examined is at a position that satisfies the values.

Therefore, in a conventional subjective optometry apparatus, a corneal aiming window 10 is generally provided in an optometry unit 8 as shown in FIG. Can be confirmed through the reflecting mirror 16 and the sighting scale 18.

However, in such a conventional subjective optometric apparatus, as shown by the phantom line in the figure, when there is an angle error in the observation direction (corneal aiming direction) by the examiner 14, the eye to be examined is examined. Since the position of No. 6 cannot be accurately confirmed on the aiming scale 18, there is a problem that it is difficult to obtain sufficient measurement accuracy.

Moreover, it is practically impossible with the conventional subjective optometry apparatus to simultaneously check both eyes 6 and 6 of the subject, and after the alignment of one eye 6 is performed,
If the positioning of the other eye 6 is performed, there is a possibility that the position of the eye to be positioned first is shifted.

Further, in such a conventional subjective optometry apparatus, the examiner 14 must frequently confirm the position of the eye 6 to be examined in order to prevent a change in the aiming distance during the examination. However, there is also a problem that the operation is troublesome and the burden on the examiner is large.

Japanese Patent Application Laid-Open No. 2-52631 discloses that
By optically detecting the position of the corneal apex (aiming distance) of the eye to be inspected by a detector such as a CCD and outputting it as an electric signal, the position of the eye to be inspected is automatically detected.
There has been proposed a subjective optometry apparatus that prevents a decrease in measurement accuracy due to an angle error in the observation direction as described above and improves operability.

However, in such an optometric apparatus, in the subjective optometric apparatus having a conventional structure as shown in FIG. 2, a detector such as a CCD is simply arranged instead of the examiner, and the aiming distance is adjusted. Since it is intended to be extracted as an electric signal, it is unavoidable that a large, complicated and expensive device such as a CCD camera or a television monitor is required as a detector thereof, and its practical use has been extremely difficult.

[0010] In addition, the size of the optometric apparatus is increased, which causes a sense of tension in the subject during the examination, and also causes a problem that it is difficult to accurately measure the refractive power of the eye.

[0011]

The present invention has been made in view of the above-described circumstances, and a problem to be solved is that the position of the eye to be inspected can be easily confirmed, and the structure is improved. An object of the present invention is to provide a simple and compact subjective optometry apparatus.

[0012]

In order to solve such a problem, the present invention includes an observation window in which a predetermined lens is interchangeably mounted, and allows an eye to be inspected to visually recognize an index from behind the observation window through the lens. as in the in the subjective optometric apparatus, prior <br/> Symbol of the cornea vertex is brought into position, a light projecting means for projecting light to a point on the optical axis of the predetermined said observation window, are symmetrically disposed across the optical axis with respect to said light emitting means, the light projected from-projecting optical means, said receiving reflected light from the corneal apex of the eye, it outputs a light reception signal received only set and means, the output of the light receiving signal from the light receiving means such that said subject's eye, the light from the light projecting means to recognize that it is located at a point on the optical axis to be projected The light projecting means and the light receiving means
Are provided in a plurality of pairs, and are placed on the optical axis of the observation window.
A plurality of light projecting means for projecting light to different points
These are symmetrically positioned across the optical axis corresponding to each of the light projecting means.
And a plurality of light receiving means to be disposed .

[0013] The present invention is also characterized by a subjective optometric apparatus in which at least a part of the light projecting path in the light projecting means and / or the light receiving path in the light receiving means is constituted by an optical fiber. .

[0014]

The present invention also relates to a subjective optometric apparatus comprising a plurality of pairs of light projecting means and light receiving means as described above, wherein the object is detected based on a light receiving signal output by the plurality of light receiving means. Also characterized in that arithmetic means for detecting the aiming distance between the corneal vertex of the optometry and the reference position of the lens and correcting the measured value of the eye refractive power in accordance with the detected value is provided. Things.

Further, the present invention is a subjective optometry apparatus having various structures as described above, wherein a light receiving state of the reflected light can be recognized from the outside based on a light receiving signal outputted by the light receiving means. Also, a device provided with a display device for displaying an image is characterized.

[0017]

In the subjective optometric apparatus having the structure according to the present invention, the corneal apex of the eye to be inspected is projected by the light emitting means only when the corneal vertex is positioned at a predetermined position. Since the light reflected by the subject's eye is incident on the light receiving means, the position of the subject's eye can be easily confirmed by the light receiving signal output by the light receiving means.

Further, in such a subjective optometric apparatus, since the position of the eye to be examined is determined by the presence or absence of light entering the light receiving means, a simple light receiving sensor can be employed as the light receiving means. There is no need to use a complicated camera such as a CCD camera, so that the simplification of the structure of the apparatus, the reduction in size, and the reduction in cost can all be effectively achieved.

Further, in such a subjective optometry apparatus,
Since it is not necessary for the examiner to directly check the position of the subject's eye by visually recognizing it, the labor of the examiner can be reduced, and the occurrence of measurement errors due to negligence in operation of the examiner can be prevented. As a result, excellent measurement accuracy can be stably obtained.

Furthermore, in at least partially self Satoshishiki optometric apparatus Do that is configured by an optical fiber of an optical path of the light projecting means and light receiving means, necessarily an optical path linearly is not necessary to set the design of the device structure The degree of freedom can be advantageously ensured, so that the apparatus can be made more compact, the manufacturability can be improved, and the like.

Further, in the own Satoshishiki optometric apparatus Do that a plurality pairs provided light projecting means and light receiving means are allowed to position the desired position the eye because of features and deep eyes of the face of the subject Even when it is difficult, the eye to be examined can be positioned with high accuracy, and the measurement of the refractive power of the eye can be advantageously performed.

Further, there is provided no calculating means for correcting the measured value in accordance with the position of the eye to be examined based on the aiming distance detected by the plural pairs of light projecting means and light receiving means.
That the own Satoshishiki optometric apparatus is be able to easily obtain the correct ocular refractive power regardless of the position of the eye, the occurrence of errors is prevented by negligence of the correction time, to simplify the measurement operation It can be achieved very advantageously.

Furthermore, in the self Satoshishiki optometric apparatus Do that is provided a display device for displaying the received light state by the light receiving unit can learn the positional deviation or the like in position and during inspection of the eye, to facilitate examiner However, measurement workability can be more advantageously improved.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

First, FIG. 1 schematically shows a configuration of a subjective optometry apparatus as one embodiment of the present invention. In this figure, reference numerals 20 and 20 denote device cases divided for the left and right eyes, and supported by a support member (not shown) so that the relative distance can be changed. It is possible to correspond.

An observation window 24 is provided in each of the device cases 20, and an inspection lens 26 is provided in the observation window 24. Although not explicitly shown in the drawings, as the inspection lens 26, a plurality of types having different refractive powers are prepared inside or outside the device case 20, and any one of the lenses is selected and exchanged. You can do it.

Then, similarly to the conventional subjective optometry apparatus, the apparatus cases 20, 20 are arranged in front of the eyes 22, 22,
The indices 28 are visually recognized by the eyes 22 to be inspected through the inspection lenses 26 set in the observation windows 24, 24, and the refraction of the eyes 22, 22 is determined by knowing the inspection lens that gives the best visual acuity. It is designed to measure.

Further, in the subjective optometric apparatus, the optical axis of the observation window 24 in which the inspection lens 26 is disposed, that is, the collimation axis of the index 28 of the eye 22 to be inspected: m, is symmetrically positioned. On both sides, a first light emitting device 30 and a second light emitting device 32 as light emitting means, and a first light receiving device 34 and a second light receiving device 36 as light receiving means are provided, respectively. . In FIG. 1, the first light emitting device 30 and the second light emitting device 32 and the first light receiving device 34 and the second light receiving device 36 are illustrated as being close to each other. By disposing each pair in the circumferential direction around the optical axis m of the observation window 24 by a predetermined amount, the arrangement structure of the apparatus can be simplified.

The first and second light projecting devices 30, 32
Are light sources 38, 38 'such as LEDs, and optical fibers 40, 40' for guiding light from the light sources 38, 38 ', respectively.
And condensing lenses 42, 42 'through which light guided by the optical fibers 40, 40' is transmitted. The light transmitted through the condenser lenses 42 and 42 'is
The light is projected onto a point on the optical axis of the observation window 24 through the light emission windows 44 and 44 ′ provided in the device case 20.

In this case, the first light emitting device 30
And the light projected through the light emitting window 44 'by the second light emitting device 32,
The light is projected onto different points separated by a predetermined distance on the optical axis of the observation window 24. In particular, in the present embodiment, the light projected by the first light projecting device 30
Standard distance from the reference position (the back of the inspection lens 26):
While the light is projected at a point separated by L = 12 mm (hereinafter, referred to as a “standard point”), the light projected by the second light emitting device 32 is further rearward on the optical axis of the observation window 24. At a point separated by a predetermined distance: L '.

On the other hand, the first and second light receiving devices 34,
36 is the first and second light emitting devices 30,
A condenser lens 46, 46 'through which light reflected by the eye 22 of the light projected at 32 is transmitted;
Optical fibers 48 and 48 'for guiding light transmitted through 46'.
And light receiving elements 50, 50 'such as photodiodes to which the light guided by the optical fibers 48, 48' is irradiated.

When the subject's eye 22 is positioned at the standard point, the light projected by the first projector 30 is
The light is reflected at the apex of the cornea of the eye 22 to be examined, and
Through the light receiving window 52 provided in the first light receiving device 34
When the subject's eye 22 is positioned a predetermined distance: L 'behind the standard point, the second projection is performed. The light projected by the optical device 32 is used to
The light is reflected at the apex of the second cornea and is incident on the second light receiving device 36 through the light receiving window 52 'provided in the device case, so that the light receiving element 50' outputs an electric signal indicating the incident state. It has become so.

Therefore, the electric signal output from the light receiving element 50 constituting the first light receiving device 34 causes the eye 22 to be examined
Can be determined whether or not is located at the standard point. Further, the electric signal output from the light receiving element 50 ′ constituting the second light receiving device 36 allows the subject's eye 22 to move from the standard point. It is possible to determine whether or not it is located at a point behind by a predetermined distance: L '.

Further, in the optometry apparatus of this embodiment,
Each device case 20 is provided with a first display lamp 53 and a second display lamp 54. Then, when an incident signal is output from the light receiving element 50 constituting the first light receiving device 34, the first display lamp 53 is turned on, and the subject's eye 22
Indicates that it is located at the standard point, and when an incident signal is output from the light receiving element 50 ′ constituting the second light receiving device 36, the second display lamp 54 is turned on, and the eye to be examined 22 indicates that it is located a predetermined distance: L 'behind the standard point.

By the way, in order to measure the eye refractive power of the eye 22 to be examined by the subjective optometry apparatus having such a structure,
First, similarly to the conventional apparatus, the apparatus cases 20 and 20 are moved so that the subject's eye 22 can visually recognize the index 28 provided in front through the inspection lens 26 provided in the observation window 24. Let me know.

Next, the forehead (not shown) is adjusted to position the eye 22 in the front-rear direction with respect to the device cases 20, 20, and the eye 22 is moved backward by a standard point or a predetermined distance: L 'from the standard point. Position. That is, the fact that the subject's eye 22 has been positioned at any of those points indicates that the first or second display lamps 53, 54.
The examiner can easily confirm by the lighting of.

In order to improve the operability when the subject's eye 22 is positioned at the standard point or at a point behind the standard point by a predetermined distance: L ', the apparatus case 2 is required.
It is effective to provide a conventionally used corneal aiming window (see FIG. 2) for 0 and 20.

Then, the first or second display lamp 53,
In the lighting state of 54, the subject's eye 22
In addition, by visually recognizing the index 28 through various inspection lenses 26, the inspection lens 26 giving the best visual acuity is provided.
The measurement of the eye refractive power is performed from the lens power of

In this case, when the measurement is performed with the first display lamp 53 turned on, that is, when the measurement is performed with the eye 22 to be examined positioned at the standard point, the inspection lens 2
The eye refractive power can be immediately known from the lens power of 6, and no correction is required.

On the other hand, when the eye 22 cannot be positioned at the standard point because of the construction of the face of the subject or the like, and the measurement is performed while the second display lamp 54 is lit, that is, the eye 22 is When the measurement is performed in a state in which the lens is positioned at a point behind by a predetermined distance: L 'from the standard point, it is necessary to correct the eye refractive power obtained from the lens power of the inspection lens 26. That is, as is known, the eye refractive power obtained from a lens of the test lens 26 and D _S, of the eye ocular refractive power: D _g is the unit of diopters, is represented by the following (Equation 1) You.

[0041] _{D g = 1000 × D S /} (1000-D S × L ') ··· ( Equation 1)

Note that such correction processing is performed by using the distance: L '
And eye refractive power: in advance calculates a correction value corresponding to the value of D _S advance to create a table or the like, resulting eye refractive power: the value of D _S, also be carried out by the examiner to correct Although it is possible, such a correction process can be automatically performed by an arithmetic unit.

Specifically, for example, the subject's eye 22 is positioned behind the standard point by a predetermined distance: L ', and an incident signal is output from the light receiving element 50' constituting the second light receiving device 36. If the measurement is performed under the condition, after the measurement,
An arithmetic unit for performing the correction calculation based on the above (Equation 1) for the obtained eye refractive power: D _S , and an output device such as a printer for outputting the eye refractive power: D _g calculated by the arithmetic unit By providing the arithmetic processing means provided,
Can be realized.

Therefore, in the subjective optometric apparatus described above, the examiner does not directly recognize the position of the eye 22 by the light receiving signals output from the first and second light receiving devices 34 and 36. Therefore, the position of the eye 22 can be easily confirmed, so that the measurement operation is easy and the burden on the examiner can be reduced, and the measurement error caused by the negligence in the operation of the examiner can be reduced. Occurrence can be prevented, and excellent measurement accuracy can be stably obtained.

In addition, in such a subjective optometric apparatus, simple light receiving elements 50 and 50 'can be employed as light receiving means, and there is no need to use a complicated device such as a CCD camera. It can be advantageously realized with a simple device structure and a compact device structure.

Further, in the optometry apparatus of this embodiment,
Since a part of the optical path in the light projecting devices 30 and 32 and the light receiving devices 34 and 36 is constituted by the optical fibers 48 and 48 ', it is not necessary to set the optical path linearly, and the degree of design freedom of the device structure is increased. It can be secured advantageously.

Further, in the optometry apparatus of this embodiment, since the light projecting apparatus and the light receiving apparatus are provided in two pairs, even when it is difficult to position the eye to be standard at the standard point, the eye to be examined can be used. The positioning can be performed with high precision, and the measurement of the eye refractive power can be advantageously performed.

Further, in the optometry apparatus of this embodiment, the light receiving state of the first and second light receiving devices 34 and 36 is displayed by the first and second display lamps 53 and 54, and the eye 22 to be inspected is displayed. It is possible to easily visually recognize whether or not the eye is located at the standard point or a predetermined position behind the standard point. The user can easily know that the measurement workability can be further improved.

Although the embodiment of the present invention has been described in detail above, this is a literal example, and the present invention is not construed as being limited to such a specific example.

For example, in the above embodiment, two pairs of the light projecting device and the light receiving device are provided, and it is determined whether the subject's eye 22 is located at two points of the standard point and the predetermined position behind the standard point. Can be detected, but it is of course possible to provide one or three or more pairs of the light projecting device and the light receiving device that make up such a pair.

Further, first and second display lamps 53,
It is also possible to adopt a buzzer or the like instead of 54,
Further, for example, in a case where the arithmetic unit is operated by the output signals from the first and second light receiving devices 34 and 36 to automatically perform the correction processing, such an external display device is necessarily required. is not.

In the above embodiment, a part of the optical path in the light projecting device and the light receiving device is constituted by an optical fiber. However, it is not always necessary to use an optical fiber.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, various changes, modifications, improvements and the like can be implemented in an embodiment,
It goes without saying that all such embodiments are included within the scope of the present invention, without departing from the spirit of the present invention.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram schematically showing a configuration of a subjective optometry apparatus as one embodiment of the present invention.

FIG. 2 is an explanatory view schematically showing a specific example of a subjective optometry apparatus having a conventional structure.

[Explanation of symbols]

 Reference Signs List 20 device case 22 eye to be examined 24 observation window 26 inspection lens 28 index 30 first light emitting device 32 second light emitting device 34 first light receiving device 36 second light receiving device 38, 38 'light source 40, 40' Optical fiber 48, 48 'Optical fiber 50, 50' Light receiving element 53 First display lamp 54 Second display lamp

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-52631 (JP, A) JP-A-4-269937 (JP, A) JP-A-54-154187 (JP, A) JP-A-54-154187 42895 (JP, A) JP-A-4-141135 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61B 3/00-3/16

Claims (4)

(57) [Claims] [Claim 1, further comprising a viewing window in which a predetermined lens is interchangeably mounted on the subject's eye, and from the rear of the observation window acuity testing apparatus so as to visually recognize the indication through the lens <br/> A light projecting means for projecting light at a predetermined point on the optical axis of the observation window, at which a corneal vertex of the eye to be examined is positioned, and symmetrical with respect to the light projecting means with respect to the optical axis. manner is disposed, the light projected from-projecting optical means, said receiving reflected light from the corneal apex of the eye, only setting the light receiving means for outputting a received light signal, the light receiving signal from the light receiving means By the output, the eye to be examined, in a device that recognizes that it is located at one point on the optical axis on which the light from the light projecting means is projected, the light projecting means and the light receiving means, Multiple pairs
Light at different points on the optical axis of the observation window.
Multiple projectors that project light and corresponding to each projector
A plurality of light receiving means symmetrically positioned with respect to the optical axis
And a subjective optometry apparatus. 2. The subjective optometric apparatus according to claim 1, wherein at least a part of a light projecting path in the light projecting means and / or a light receiving path in the light receiving means is constituted by an optical fiber. 3. An aiming distance between a corneal vertex of the eye to be examined and a reference position of the lens is detected based on light receiving signals output by the plurality of light receiving means, and an eye refractive power is determined according to the detected value. the subjective optometry apparatus according to claim 1 or 2 operating means is provided for correcting the measured value. 4. Based on the light receiving signal output by said light receiving means, according to any one of claims 1 to 3 display device is provided for recognizably displaying the light receiving state of the reflected light from the outside A subjective optometry device.