JP2004012673A - Spectacles for aged - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide spectacles for the aged capable of seeing even a medium and long distance clearly. <P>SOLUTION: Lenses 2 for the presbyopia consisting of two pieces of convex lenses are fitted to a spectacle frame 1 and, thereto, temples 3 and nose pads 4 are attached. On the upper side of a horizontal upper marginal part 1a of the spectacle frame 1, an upper horizontal member 6 is attached via a connection member 5 and a slit S of a fine interval is formed between the member 6 and the upper marginal part 1a of the spectacle frame 1. The inverse astigmatism often concurs in the presbyopia. When a person of the inverse astigmatism looks at a middle and long distance through the slit S, the lens effect of upper and lower vertical meridian (minimal meridian) is weakened, the lens effect of horizontal meridian (maximal meridian) is more emphasized and the image is formed on the front focal line. Because the front focal line of the aged having the inverse astigmatism is near the retina, the middle and long distance becomes clearly visible. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is a reading glasses that can be viewed from the middle and distant while being worn, and in particular, by providing a horizontal narrow slit having a function of correcting astigmatism above the presbyopic lens, to provide both presbyopia and astigmatism. The present invention relates to reading glasses that allow a person having the above-mentioned lens to clearly see a target in the middle and distant places during near work using a presbyopic lens.
[0002]
[Prior art]
First, basic ophthalmological matters will be described. The accommodative power of an eye with a clear vision distance of 25 to 30 cm is 3 to 4 D (diopter). Is called presbyopia. The accommodation power decreases with age, and becomes 2-4D at the age of 45. Therefore, presbyopia will soon appear from the age of about 45.
[0003]
Since myopic eyes are easy to see in the near area, even if the accommodation power of the eyes decreases due to aging, the nearsightedness of the myopic glasses may be reduced depending on the degree of myopia, or the myopic glasses may be removed just right, or by using a weak convex lens. You can see
[0004]
However, in the case of the emmetropic eye or the hyperopic eye, if the accommodation power of the eye decreases due to aging, the decrease in the accommodation power of the eye is compensated for by the convex lens when viewing the near area. This is reading glasses.
[0005]
In addition, astigmatism refers to a refraction state of the eye in which light rays emitted from one point in the external world do not form a single point outside or inside the eye, and a horizontal diameter line and a vertical diameter line are orthogonal to each other. That the focal line is shifted back and forth is called astigmatism. Further, the case where the strongest main diameter line in the regular astigmatism is vertical is called direct astigmatism, and the case where it is horizontal is called astigmatism. And, strictly speaking, most eyes have some astigmatism.
[0006]
In old age, the accommodation power of the eye decreases with aging and presbyopia progresses, while astigmatism tends to increase with aging, and the degree of astigmatism also progresses. It is said that the cause is that the curvature of the vertical line of the cornea becomes small, the linear astigmatism decreases, and the lens astigmatism that tends to be astigmatism increases. According to “Refraction Error and Correction thereof (Revision 3rd Edition)” (Kanehara Shuppan P.136), 66.9% of those aged 60 to 80 have astigmatism.
[0007]
FIG. 11 shows a schematic diagram of the astigmatism. Inverted astigmatism is one of regular astigmatism, and in regular astigmatism the horizontal and vertical lines are orthogonal. In astigmatism, the horizontal radius line has a strong refractive power (strong principal radius line), light emitted from one point at infinity is imaged at the front focal line, and the vertical radius line has a weak refractive power ( Similarly, light emitted from one point at infinity forms an image at the back focal line.
[0008]
If the accommodation power of the eye decreases due to aging, hyperopia tends to occur as a whole, so that in astigmatism due to aging, the front focal line is closer to the retina than the rear focal line. The area between the focal lines before and after the focal line is called a focal area, which indicates the strength of astigmatism. Further, a portion slightly near the front focal line in the middle of the focal region is called a minimum scattering circle.
[0009]
Normally, astigmatic people focus on this minimum scattering circle. If the accommodation power of the eye is sufficient, whichever of the anterior focal line or the posterior focal line, which requires the least amount of accommodation effort, is imaged on the retina and clearly seen.
[0010]
In the case of astigmatism in the elderly, the degree of astigmatism that increases as the eye becomes presbyopic and the accommodation power of the eye progresses increases, and the focal area becomes larger. Get farther from the retina. In addition, since the accommodation power of the eye is reduced, it is no longer possible to form an anterior focal line on the retina, and the subject is viewed as a blurred retinal image at mid-to-far distances.
[0011]
Conventionally, as spectacles for the elderly having both presbyopia and astigmatism, spectacles combining a convex lens for correcting presbyopia and a cylindrical lens for correcting astigmatism, i.e., for both short distance and middle distance There are glasses. However, glasses of this type, including measurement of astigmatism, are relatively expensive, and sometimes overcorrection or spatial distortion may be a problem.
[0012]
[Problems to be solved by the invention]
For example, it is often the case that a person becomes a presbyopic eye and suddenly loses his / her gaze and looks at a mid-to-far distance target through the upper edge of the reading glasses during short-distance work or reading using the reading glasses. Then, since many of the elderly are astigmatism, the mid-distance target that the astigmatized elderly person sees with the naked eye always looks a little blurred. Nevertheless, I often leave it undisturbed in my daily life.
[0013]
However, as described above, when the user looks away from the reading glasses and looks at a target at a medium or long distance, there is a case where the user wants to see these more clearly. For example, there are many examples, such as the expression of a grandchild who has returned, characters on a TV screen, and birds and trees outside a window.
[0014]
SUMMARY OF THE INVENTION An object of the present invention is to provide a reading glasses that solves the above-described problems, corrects astigmatism associated with presbyopia with a lighter, simpler, and less expensive configuration, and allows a user to clearly view middle and near distances while wearing the reading glasses. Is to do.
[0015]
[Means for Solving the Problems]
In order to achieve the above object, the reading glasses according to the present invention are characterized in that narrow slits are formed in the horizontal direction above the presbyopic lens.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention will be described in detail based on the embodiment shown in FIGS.
FIG. 1 is a schematic view of the reading glasses according to the first embodiment, and a so-called presbyopic lens 2 composed of two convex lenses is fitted in an eyeglass frame 1. A vine 3 and a nose hook 4 are attached to the spectacle frame 1. An upper horizontal member 6 is attached above the linear horizontal upper edge 1a of the spectacle frame 1 via a connecting member 5, and a slit S at a fine interval between the upper horizontal member 6 and the upper edge 1a of the spectacle frame 1. Is formed.
[0017]
In this case, the upper edge 1a of the spectacle frame 1 also serves as the lower horizontal member, but a lower horizontal member may be provided separately from the upper edge 1a of the spectacle frame 1. That is, as shown in FIG. 2, the lower horizontal member 7 may be mounted on the upper edge 1 a of the spectacle frame 1, and the upper horizontal member 6 may be connected via the connecting member 8 at the center of the spectacle frame 1.
[0018]
The eyeglass frame 1, the upper horizontal member 6, and the lower horizontal member 7 are preferably opaque members.
[0019]
By forming the slits S above the reading glasses in this way, when the reading glasses are used, the middle distant can be clearly seen when the middle distant is viewed through the slits S for upper sight use. Although the slit S has a drawback that the upper and lower fields of view are relatively narrow, it is a relatively limited application that is used when one wants to clearly see the mid-to-far distance during near work using the presbyopic lens 2. Considering that it is small, lightweight, simple, and inexpensive, this is a sufficiently acceptable range.
[0020]
Here, the reason why the slit S has the effect of correcting the astigmatism will be described. First, as shown in FIG. 3, while gazing at a target, a plate having a horizontal edge is brought from below in front of the astigmatism, and the lower field of view is brought close to the visible target. The area directly above the horizontal edge can be seen more clearly. This is because the lens effect below the vertical diameter line (weak main diameter line) is hindered, and the lens effect of the horizontal diameter line (strong main diameter line) is emphasized immediately above the edge, and the image is focused on the front focal line. Because you do. The prefocal line of old people's astigmatism will be better visible because it is closer to the retina.
[0021]
Similarly, when the horizontal edge is brought from above in front of the astigmatism eye while paying attention to the target, and is brought very close to the visible target, the area immediately below the close edge is clearly seen for the same reason.
[0022]
In this way, when the elderly person with astigmatism sees the target through the slit S, the luminous flux from the vertical radius line (the weak main radius line), that is, the luminous flux from the horizontal radial line (the strong main radius line) Focuses on the anterior focal line, and the anterior focal line is closer to the retina so that the target can be seen more clearly.
[0023]
FIG. 4 is a perspective view of the reading glasses according to the second embodiment, and the same members as those in the first embodiment are denoted by the same reference numerals. In the present embodiment, the central portion 6a of the upper horizontal member 6 is curved forward so that the upper horizontal member 6 avoids the bridge 9 at the central portion of the spectacle frame 1. The upper horizontal member 6 is screwed to the connecting member 5 via a screw 10 so that the width of the slit S can be adjusted.
[0024]
FIG. 5 shows a front view of the reading glasses of the third embodiment, in which upper horizontal members 6 and 6 are separately provided above the reading lenses 2 of both eyes of the spectacle frame 1, and the reading glasses are provided. The upper edge 1a of the spectacle frame 1 is curved along 2, and the upper horizontal members 6, 6 are similarly curved. Accordingly, the slit S is also formed to have a forwardly convex shape along the curve of the upper edge portion 1a and the upper horizontal member 6.
[0025]
FIG. 6 is a perspective view of the reading glasses according to the fourth embodiment. In the case where the upper horizontal member 6 is connected to the upper edge portion 1a at a predetermined interval via two hinges 11, and the slit S is not used. The upper horizontal member 6 can be folded down, and can be stored in a small size by overlapping with the upper edge 1a of the spectacle frame 1.
[0026]
FIG. 7 is a perspective view of a slit unit 12 according to the fifth embodiment, in which an upper horizontal member 6 is attached via a screw 14 to a lower horizontal member 7 having a locking portion 13 for engaging the spectacle frame 1 on both sides. Have been.
[0027]
As shown in FIG. 8, the slit unit 12 can be detachably attached to the upper edge 1a of the spectacle frame 1.
[0028]
FIG. 9 is a perspective view of the reading glasses according to the sixth embodiment, in which the lower horizontal member 7 is fixed to the upper edge 15a of the simple reading glasses 15 made of synthetic resin such as plastic without using the glasses frame 1 via screws 16. Further, the upper horizontal member 6 is fixed via the connecting member 17, and the interval between the slits S can be arbitrarily adjusted by changing the position of the screw.
[0029]
FIG. 10 is a perspective view of the reading glasses according to the seventh embodiment, in which horizontal members 18 and 19 are provided in two steps via a connecting member 20 on the upper edge 1a of the spectacle frame 1, and the slit S Are formed in two rows. In this way, by providing the horizontal members 18 and 19 in two steps, the narrowness of the field of view of the width of the slit S can be compensated to some extent. In this embodiment, two horizontal members 18 and 19 are provided, but horizontal members may be provided in more stages.
[0030]
【The invention's effect】
As described above, the presbyopic glasses according to the present invention are provided with slits at narrow intervals along the horizontal direction capable of correcting the astigmatism above the presbyopic lens. However, you can clearly see mid-to-far distance targets as needed.
[Brief description of the drawings]
FIG. 1 is a perspective view of a first embodiment.
FIG. 2 is a perspective view of a second embodiment.
FIG. 3 is an explanatory diagram of an operation effect.
FIG. 4 is a perspective view of a second embodiment.
FIG. 5 is a perspective view of a third embodiment.
FIG. 6 is a perspective view of a fourth embodiment.
FIG. 7 is a perspective view of a slit unit.
FIG. 8 is a perspective view of a fifth embodiment.
FIG. 9 is a perspective view of a sixth embodiment.
FIG. 10 is a perspective view of a seventh embodiment.
FIG. 11 is an explanatory diagram of astigmatism.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Eyeglass frame 2 Presbyopia lens 3 Vine 4 Nose hook part 5, 8, 17, 20 Connecting member 6 Upper horizontal member 9 Lower horizontal member 9 Bridge 10, 14, 16 Screw 11 Hinge 12 Slit unit 13 Locking part 18, 19 Horizontal member

Claims (4)

A pair of reading glasses, characterized in that slits are formed at narrow intervals along the horizontal direction above the presbyopia lens. The reading glasses according to claim 1, wherein the slit is provided in a part of an eyeglass frame. The reading glasses according to claim 1, wherein the slit is provided by disposing another member on an eyeglass frame. The reading glasses according to claim 1, wherein an interval between the slits is adjustable.

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