JP2002156611A - Presbyopia compensating lens for spectacles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compensating lens for presbyopia which can simply dissolve diopter mismatching of spectacles of daily use due to presbyopia at a low cost. SOLUTION: The compensating lens 20 which is made of a light translucent material having flexibility and elasticity and is a convex lens of a prescribed compensating degree is attached to the rear surface 22 of the spectacles lens 21 in a tightly adhered state to simply dissolve diopter mismatching of the spectacles of daily use due to presbyopia at a low cost. Since the compensating lens 20 is made of a material having flexibility, elasticity and further light transmissivity, the compensating lens can be tightly attached to the rear surface 22 of the spectacles lens 21 by being easily elastically deformed along the rear surface thereof to prevent inconvenience of falling off of the compensating lens 20 from the rear surface 22 of the spectacles lens 21 from occurring. Further, since the compensating lens has impact resistance, breakage of the spectacles lens by impact force due to falling, collision or the like is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of easily attaching to a spectacle lens worn for correcting refractive errors such as myopia, hyperopia, and astigmatism, and correcting a power mismatch of the spectacle lens due to presbyopia. The present invention relates to a presbyopia correcting lens for spectacles that can perform the following.

[0002]

2. Description of the Related Art Even a person with normal vision with no refractive error and normal vision has a near point distance of about 25 cm around 45 years old. As the age increases, the accommodation power of visual acuity with respect to the near point decreases, and when the near point distance increases to 30 cm or more, it is called presbyopia. In presbyopia, due to the hardening of the outer lens layer and the increase in the refractive index, it becomes impossible to form an image of a nearby object on the fundus, resulting in symptoms such as impaired near vision and eye fatigue. The treatment can be corrected by supplementing the refractive power of the lens with a convex lens.

In recent years, in a diversified living environment, wearers of glasses and contact lenses have been forced to take various measures. As the population ages, the population that encounters the reality of presbyopia is on the rise. Originally, it is preferable to have a plurality of glasses and contact lenses according to the purpose of use, for example, for near and distant purposes.However, it is necessary to change the glasses each time the object to be viewed is different, and to always wear a plurality of glasses. Carrying it is troublesome and inconvenient for the wearer. In particular, replacement according to the purpose of the glasses is burdensome for the elderly and physically handicapped who cannot move their limbs freely, compared to healthy people. Often, they spend nothing. The situation in which the viewpoint is not correct despite wearing eyeglasses in this way is not safe for elderly and physically handicapped persons because the surrounding situation is not clearly recognized, and in terms of avoiding danger. There is a problem of inferiority.

[0004] In addition, the decrease in visual acuity due to presbyopia progresses with aging, so that the near point distance gradually decreases, and in order to correct this decrease in visual acuity, the presbyopia has a frequency corresponding to the newly reduced visual acuity. There is a problem that it is necessary to purchase eyeglasses or exchange lenses, which is not economical.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a presbyopic correction lens which can easily and inexpensively eliminate the power mismatch due to presbyopia of commonly used spectacles. is there.

[0006]

The present invention according to claim 1 is made of a light-transmitting material having flexibility and elasticity,
A presbyopic correction lens for spectacles, which can be provided in close contact with the back surface of a spectacle lens, and a convex lens having a predetermined correction power is formed in an optical region.

According to the present invention, when a wearer of spectacles for correcting refractive errors such as myopia, hyperopia and astigmatism develops presbyopia with aging, the presbyopia correcting lens for spectacles (hereinafter referred to as "correction"). The lens may be abbreviated as a lens) on the back surface of the spectacle lens, that is, the surface facing the eyeball, in a tightly contacted state by a well-known method such as vacuum suction and adhesion. It is possible to eliminate the power mismatch caused by presbyopia of the eyeglasses.

[0008] Such a presbyopic correction lens for spectacles corrects a refractive error caused by presbyopia, in which the lens cannot respond normally to near-sighted vision and forms an image behind the retina. For this purpose, a convex lens is used. An arbitrary curved surface shape is selected for the front surface facing the spectacle lens and the rear surface facing the eyeball according to the shape of the back surface of the spectacle lens and the degree of progress of presbyopia.

Further, since the presbyopic correcting lens for spectacles is made of a material having flexibility, elasticity and translucency, it can be easily elastically deformed along the back surface of the spectacle lens as described above. To prevent it from falling off easily from the back of the spectacle lens, and has impact resistance, and can be carried by itself without being attached to the spectacle lens or attached to the spectacle lens. In any of the above states, it can be prevented from being easily broken by the action of an external force due to a fall or a collision.

According to a second aspect of the present invention, in the presbyopic correcting lens for spectacles, the projection shape on a virtual plane perpendicular to the geometric center axis is 15 to 22 mm in the long side direction and 8 to 22 in the short side direction. It is characterized by a 15 mm oval.

According to the present invention, in the presbyopic correcting lens for spectacles, the projected shape has an elliptic shape having a length of 15 to 22 mm in a long side direction and a length of 8 to 22 mm in a short side direction. So, it is attached to the lower half of the back of the spectacle lens and used for near use, the upper half of the spectacle lens is used for distance use,
The so-called bifocal glasses can be easily and inexpensively realized. In addition, by attaching the presbyopia correcting lens for spectacles to the back surface of the spectacle lens such that the left-right direction is the longitudinal direction, a wide field of view in the left-right direction can be secured.

According to a third aspect of the present invention, the correction power of the optical region is selected from +1.0 to +4.0 diopters.

According to the present invention, the correction power of the optical region is +1.0 to +4.0 diopter (Diopter;
By selecting a value in the range of (abbreviated as D), it is possible to correct for near vision impairment due to presbyopia ranging from mild to strong. Such a range of the correction frequency is, for example, +
1.0D, + 1.5D, + 2.0D, + 2.5D, +
0.5D, such as 3.0D, + 3.5D, + 4.0D
It may be realized by a correction lens having a different power every time, or may be realized as a correction lens having a different power every 0.1D, 0.2D, or 0.3D. By selecting the correction power from +1.0 to +4.0 D in this way, it is not necessary to prepare lenses having many different powers, and it is possible to correct a decrease in near vision caused by presbyopia over a wide range. Becomes

According to a fourth aspect of the present invention, at least the front surface of the spectacle lens which is in close contact with the back surface is formed to be curved in advance along the back surface of the spectacle lens.

According to the present invention, since the front surface of the correction lens is curved along the back surface of the spectacle lens, the correction lens is brought into close contact with the back surface of the spectacle lens with little deformation, and the elastic recovery force of the correction lens The uniformity can be achieved by eliminating variations in the state of adhesion to the back surface of the spectacle lens due to the above. As a result, a minute gap is generated between the correction lens and the spectacle lens, and the inconvenience of air entering the gap and locally changing the refractive index is prevented. A correction lens capable of forming an image of the transmitted light on the fundus of the spectacle wearer can be easily and inexpensively realized.

According to a fifth aspect of the present invention, the curvature of the front surface which is in close contact with the back surface of the spectacle lens is selected to be smaller than the curvature of the back surface of the spectacle lens.

According to the present invention, the curvature of the front surface of the correction lens is selected to be smaller than the curvature of the back surface of the spectacle lens, that is, the curvature radius of the front surface of the correction lens is smaller than the curvature radius of the back surface of the spectacle lens. By being selected to be large, the peripheral portion of the correction lens is earlier than the inner region, and in a state in which it is in contact with the back surface of the spectacle lens, by pressing the inner region with fingers, so to speak, as in a sucker. The correction lens can be attached to the spectacle lens and easily attached. In this case, the air between the inner area and the back surface of the spectacle lens is pushed out from the peripheral portion when pressed by the finger as described above, so that the correction lens can be brought into close contact with the back surface of the spectacle lens. it can. Therefore, there is no possibility that an air layer is interposed between the correction lens and the spectacle lens, and the correction lens and the spectacle lens can be optically coupled easily and reliably.

[0018]

FIG. 1 is a sectional view showing a presbyopia correcting lens 20 for spectacles according to an embodiment of the present invention. The presbyopic correction lens for spectacles (hereinafter, sometimes simply referred to as a correction lens) 20 of the present embodiment is made of a light-transmitting material having flexibility and elasticity, and is adhered to the back surface 22 of the spectacle lens 21. It is provided in the state where it was set. The correction lens 20 has an optical region 23 forming a convex lens, and a bevel portion 24 connected to a peripheral portion of the optical region 23. The optical region 23 includes, as described later, the type of refraction abnormality of the wearer and the type thereof. It has a predetermined correction frequency corresponding to the degree.

In the present embodiment, the unit representing the strength of the reinforcing lens 20 and the spectacle lens 21 is a reciprocal of the focal length measured in meters, using a diopter (symbol D). The sign of + is given for a convex lens and the sign of-is given for a concave lens. When the reinforcing lens 20 and the spectacle lens 21 are in a superimposed state as shown in FIG.
The integral diopter is given by the algebraic sum of the diopters of each lens 20,21.

The spectacle lens 21 is realized by, for example, one of a crown glass lens having a refractive index of 1.523, a surface-hardened plastic lens, a high-refractive-index glass lens, a tempered glass lens, and the like. From the point of view of use, it may be realized by any one of a distance lens, a near lens, a bifocal lens in which distance and near are integrated, and a progressive multifocal lens.

From the viewpoint of performance, the spectacle lens 21 is made of a colored lens having a light-transmitting effect, a coated lens which removes reflection on the lens surface by using light interference, and a silver chloride which reacts to ultraviolet rays contained in sunlight. It may be realized by any of a photochromic lens (also referred to as a dimming lens) that changes the color depth by mixing with a material, a polarizing lens that selectively removes reflected light from a water surface or the like.

In such a spectacle lens 21, astigmatism is mainly removed so that a good-quality image can be obtained even when the user moves his / her line of sight. For an image from infinity, a concave lens is used to form an image in front of the retina in myopia, and a convex lens is used to form an image behind the retina in hyperopia.

The correction lens 20 is provided with a presbyopi
a, also referred to as presbyopia). This presbyopia occurs because the accommodation function of the eye 26 is weak, and is different from refractive errors such as myopia and hyperopia. A state in which there is no refractive error is referred to as emmetropia. In an emmetropic eye, an image is formed on the retina 27 when viewing a distant object. Inflating the lens 29 acting as a lens to focus on the retina 30 as shown by the imaginary line 31 and changing the thickness of the lens 29 according to the required distance to adjust the eye normally. Can be. However, in presbyopia, since the crystalline lens 29 is hardened and its elasticity is weakened, this adjusting function is weakened, and it becomes impossible to clearly see the vicinity. Therefore, in the case of refractive error, without adjustment
In other words, when viewed from a distance, the image does not form an image on the retina 30, and thus is essentially different from presbyopia.

The accommodation ability of the eye becomes weaker with age, and the accommodation ability of children is up to 10D or more (that is, 1).
4 years old at 40 years old
D (up to 25 cm), 1D (up to 1 m) at the age of 50, and almost disappears at the age of 60. For example, in order for a person with normal vision to clearly see a distance of 25 cm in front of the eyes (this distance is referred to as the clear distance), 4D adjustment is required. , At 50, only 1D can be adjusted,
Lack of 3D accommodation. To make up for this shortage,
A correction lens 20 forming a convex lens of D is used. Such a correction lens 20 is used to compensate for the lack of visual acuity when looking at the near area, and can be called a near correction lens, and is distinguished from a distance lens that corrects myopia and hyperopia. .

The material of the correction lens 20 is, for example, polymethyl methacrylate (abbreviated as PMM) in a hard synthetic resin as an example of a light-transmitting material having flexibility and elasticity.
A) can be used, and in the case of a soft synthetic resin system, hydroethyl methacrylate (abbreviation: HEMA) can be used.

FIG. 2 shows a spectacle lens 2 viewed from the right in FIG.
Correction lens 20 mounted on back surface 22
3 is a sectional view taken along line III-III of FIG.
It is the expanded sectional view seen from FIG. In a state where the correction lens 20 is not attached to the spectacle lens 21, that is, as shown in FIG. 3, in a state where there is no deformation due to an external force, a projection shape on a virtual plane perpendicular to the geometric center axis L 1 passing through the center of gravity G Has a width a = 15 in the long side direction perpendicular to the plane of FIG.
3 to 22 mm, and the vertical width b =
It is an oval convex lens of 8 to 15 mm. The correction power of the optical region 23 is selected from +1.0 to +4.0 diopters.

As described above, when the wearer of spectacles for correcting refractive errors such as myopia, hyperopia and astigmatism advances presbyopia with aging, the correction lens 20 is replaced with the spectacle lens. 21 is attached to the back surface 22, that is, the surface on the side facing the eyeball, by a known method such as vacuum suction and adhesion, and is simple and inexpensive. The alignment can be eliminated. Such a correction lens 20
The front surface 33 facing the spectacle lens 21 and the rear surface 34 facing the eyeball have an arbitrary curved surface and planar shape such that an appropriate power is obtained according to the shape of the back surface 22 of the spectacle lens 21 and the degree of progress of presbyopia. Selected. In the present embodiment, the width of the bevel portion 24 can be reduced by making the front surface 33 substantially flat, so that the entire correction lens 20 can be reduced.

Since the correction lens 20 has flexibility and elasticity as described above, the back surface 2 of the spectacle lens 21 is
2 can be easily elastically deformed and kept in close contact with each other, and easily come off the back surface 22 of the spectacle lens 21 without a large change in refractive index due to bending stress. Can be prevented. In addition, since the correction lens 20 has flexibility and resiliency, impact resistance is obtained, and the correction lens 20 is attached to the spectacle lens 21 or carried alone without being attached to the spectacle lens 21. However, even if an external force such as an impact force due to a drop or a collision is applied, it is possible to prevent the breakage easily.

Further, the correction lens 20 of the present embodiment
It has a length of 15-22 mm in the long side direction and 8 in the short side direction.
Since it is an ellipse having a length of about 22 mm, the lower half of the back surface 22 of the spectacle lens 21, more specifically, about 2 optical axes L2 passing through the optical center G2 of the optical area 23.
The lower half of the spectacle lens 21 is attached to an area below the virtual plane 36 in the long side direction (the left-right direction in FIG. 2) passing below and used for near vision. The part is used for distance use, so that so-called bifocal glasses can be easily and inexpensively realized. Further, by attaching the correction lens 20 to the back surface of the spectacle lens so that the left-right direction is the longitudinal direction, a wide field of view in the left-right direction can be secured.

In the embodiment of the present invention, the curvature of the front surface 33 which is in close contact with the back surface 22 of the spectacle lens 21 is selected to be smaller than the curvature of the back surface 22 of the spectacle lens 21. In other words, the radius of curvature of the front surface 33 of the correction lens 20 is selected to be larger than the radius of curvature of the rear surface 22 of the spectacle lens 21. Thereby, in a state where the bevel portion 24 which is the peripheral portion of the correction lens 20 is brought into contact with the back surface 22 of the spectacle lens 21 before the inner optical region 23, the inner region is pressed by a finger. In other words, the correction lens 20 can be easily attached to the spectacle lens 21 by sucking the correction lens 20 like a suction cup. In this case, since the air in the gap between the inner optical region 23 and the back surface 22 of the spectacle lens 21 is pushed out from the bevel portion 24 when pressed by the finger as described above, the correction lens 20 It can be in close contact with the back surface 22 of the spectacle lens 21. Therefore, there is no possibility that an air layer is interposed between the correction lens 20 and the spectacle lens 21, and the correction lens 20 and the spectacle lens 21 can be easily and reliably optically coupled.

In the correction lens 20, the optical region 2
By selecting the correction power of 3 in the range of +1.0 D to +4.0 D as described above, a wide range of nearsightedness due to presbyopia ranging from mild to strong can be used. Such correction frequency ranges are, for example, + 1.0D, +1.
5D, + 2.0D, + 2.5D, + 3.0D, +3.5
D, + 4.0D, may be realized by a plurality of correction lenses having different powers every 0.5D, or 0.
It may be realized as a correction lens having a different power every 1D, 0.2D, or 0.3D. By selecting the correction power from +1.0 to + 4.0D in this way, it is not necessary to prepare lenses having many different powers, and high productivity and utilization can be achieved.

FIG. 4 shows a storage case 40 for the correction lens 20.
FIG. 5 is a perspective view showing an example of FIG.
It is sectional drawing seen from V. The above-described correction lens 20 is stored in a storage case 40 together with an infiltration liquid 41 such as a physiological saline solution in order to prevent dust and fungi from adhering and being damaged. The storage case 40 includes a case body 43 in which a pair of storage recesses 42 a and 42 b forming a part of a pair of left and right spherical surfaces is formed, and the storage recesses 42 a and 42 a of the case body 43.
And a lid sheet body 45 attached to a flat base portion 44 connected to the base member 42b. The storage case 40 is realized as a package 47 in which a plurality of units are separable via a perforation 46.

The case body 43 is made of a thermoplastic synthetic resin, and the cover sheet body 45 is made of an aluminum vapor-deposited film. When used, the cover sheet 45 is peeled off to remove the correction lens 20 in each of the storage recesses 42a and 42b.
Can be taken out with fingers and attached to the back surface 22 of the spectacle lens 21 while being pressed and sucked. With such a storage case 40, the correction lens 20 can always be kept in a sanitary state, can be prevented from being damaged, and good portability can be realized.

In another embodiment of the present invention, at least the front surface 33 of the correction lens 20 which is in close contact with the back surface 22 of the spectacle lens 21 is formed by bending in the same direction along the back surface 22 of the spectacle lens 21 in advance. Is done. According to such a configuration, the front surface 33 of the correction lens 20 is
Of the spectacle lens 21 to the back surface 22 of the spectacle lens 21 due to the elastic recovery force of the correction lens 20 by being curved along the back surface 22 of the spectacle lens 21 with little deformation. Variation,
That is, it is possible to eliminate the disadvantage that the adsorption strength varies depending on the position, and to achieve uniform contact. As a result, a minute gap is partially generated between the correction lens 20 and the spectacle lens 21, and the inconvenience of air entering the gap and locally changing the refractive index is prevented. The light that has passed through the optical region 23 can be reliably imaged on the fundus of the spectacle wearer.

[0035]

According to the first aspect of the present invention, the correction lens is attached to the back surface of the spectacle lens by a well-known technique such as vacuum suction and adhesion in a state in which the correction lens is in close contact with the eyeglass lens. It is possible to eliminate the power mismatch caused by presbyopia of the eyeglasses. Further, since this correction lens is made of a material having flexibility, elasticity and translucency, it is easily elastically deformed and adhered along the back surface of the spectacle lens as described above, and In addition to being able to prevent the problem of easily falling off from the back, it has impact resistance, and can be used either in a state where it is attached to the spectacle lens or in a state where it is carried alone without being attached to the spectacle lens. However, it is possible to prevent the device from being easily damaged by the action of an external force due to a fall or a collision.

According to the second aspect of the present invention, the correction lens has a length of 15 to 22 mm in the long side direction and a length of 8 to 22 mm in the short side direction.
Since it is an ellipse having a length of 22 mm, bifocal glasses can be easily and inexpensively realized simply by attaching a correction lens to a spectacle lens. In addition, by attaching the presbyopia correcting lens for spectacles to the back surface of the spectacle lens such that the left-right direction is the longitudinal direction, a wide field of view in the left-right direction can be secured.

According to the third aspect of the present invention, since the correction power of the optical region is selected in the range of +1.0 D to +4.0 D, correction is made for near vision impairment due to presbyopia ranging from mild to strong. Therefore, it is not necessary to prepare lenses having many different powers, and it is possible to correct a decrease in nearsighted visual acuity due to a wide range of presbyopia.

According to the fourth aspect of the present invention, since the front surface of the correction lens is curved along the back surface of the spectacle lens, the variation in the state of adhesion to the back surface of the spectacle lens due to the elastic recovery force of the correction lens. The gap between the compensating lens and the spectacle lens is minimized, which prevents the intrusion of air into the gap and the local change in the refractive index. Thus, it is possible to easily and inexpensively realize a correction lens capable of forming an image of the light that has passed through the optical region on the fundus of the spectacle wearer.

According to the present invention, the curvature of the front surface of the correction lens is selected to be smaller than the curvature of the back surface of the spectacle lens, so that the correction lens is attracted to the spectacle lens like a suction cup. The correction lens and the spectacle lens can be surely optically coupled without interposing an air layer between the correction lens and the spectacle lens.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a presbyopia correcting lens for glasses 20 according to an embodiment of the present invention.

FIG. 2 is a rear view 22 of the spectacle lens 21 viewed from the right in FIG.
FIG. 4 is a front view of the correction lens 20 in a state where the correction lens 20 is mounted on the correction lens 20.

FIG. 3 is an enlarged cross-sectional view taken along the line III-III of FIG. 2;

FIG. 4 is a perspective view showing an example of a storage case 40 of the correction lens 20.

FIG. 5 is a cross-sectional view taken along the line VV of FIG. 4;

[Explanation of symbols]

 Reference Signs List 20 presbyopia correcting lens for spectacles 21 spectacle lens 22 back surface 23 optical region 24 bevel portion 26 eye 27 retina 28 ciliary muscle 29 crystalline lens 33 front surface 40 storage case 41 infiltration liquid 42a, 42b storage recess 43 case body 44 base 45 lid Sheet 46 perforation

Claims (5)

[Claims] 1. A lens made of a light-transmitting material having flexibility and elasticity, which can be provided in close contact with the back surface of a spectacle lens, and a convex lens having a predetermined correction power is formed in an optical area. A presbyopic correction lens for eyeglasses, characterized in that: 2. A projection shape on a virtual plane perpendicular to the geometric center axis is 15 to 22 mm in a long side direction and 8 to 22 in a short side direction.
2. The presbyopic correcting lens for spectacles according to claim 1, wherein the lens is a 15 mm oval. 3. The correction frequency of the optical region is from +1.0 to
3. The presbyopic correction lens for spectacles according to claim 1, wherein the lens is selected to be +4.0 diopters. 4. The method according to claim 1, wherein at least a front surface which is in close contact with the back surface of the spectacle lens is formed to be curved in advance along the back surface of the spectacle lens.
4. The presbyopic correction lens for eyeglasses according to any one of the above. 5. The spectacles according to claim 1, wherein the curvature of the front surface which is in close contact with the back surface of the spectacle lens is selected to be smaller than the curvature of the back surface of the spectacle lens. Presbyopia correction lens.