JPH0234658Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an auxiliary tool for fitting a progressive multifocal lens into an eyeglass frame.

<Prior art> In recent years, a near lens with the addition power necessary for reading, etc. and a distance lens for seeing far distances have been cemented into a single lens with the addition power at the boundary being progressively changed. Bifocal lenses, that is, progressive multifocal lenses, have become popular. Unlike single-focal lenses, this lens has a complicated lens design, so it is important to check the quality of the manufacturing of the lens fabric, and whether the combined distance power and near addition power are compatible. In addition, it is essential that the lens fabric be correctly fitted into the eyeglass frame so that the wearer's distance vision passes through the distance center of the spectacle lens, and the near vision passes through the near center. If this condition is not met, even if you use glasses with lenses of a power that exactly matches the vision of the wearer, not only will it not be possible to correct or correct the vision of the wearer, but the eyesight will be shifted from the center. Correct fitting of the lens fabric into the eyeglass frame is extremely important, since the prismatic effect of the lens can cause visual impairment.

Therefore, as a conventional technique to achieve the purpose of correctly fitting the lens fabric into the eyeglass frame,
There is a method in which an eyeglass frame fitted with a temporary lens without a prescription is placed on the frame, and the person facing the measurement visually marks the position of the center of the pupil on the temporary lens. Take a photo of the left and right eye area with the eyeglass frame on from directly in front.
A method of determining the pupil position based on the photograph and aligning the optical center is disclosed.

On the other hand, this lens fabric has optical centers at fixed positions at the top and bottom where distance and near vision should pass, allowing both distance and near vision to be performed appropriately. In order to achieve this, there must be a certain minimum required lens distance above and below from both centers.

Therefore, in order to obtain progressive multifocal eyeglasses that are comfortable to wear, it is necessary to select an appropriate eyeglass frame. Face shapes vary from person to person, and eyeglass frames come in a variety of sizes and shapes. For regular eyeglasses, it is sufficient to select a frame that perfectly fits the wearer's face shape and suits his/her preferences, but for bifocal glasses, other conditions must be met to allow for proper bifocal vision work. Some existing eyeglass frames may not be suitable at all, and what may be suitable for some people may not be suitable for others.
It is possible that the suitability may be changed with some modification.

Therefore, Japanese Patent Publication No. 18742/1987 describes a jig for easily identifying whether or not the frame has the appropriate height, that is, the vertical width, for the wearer to use as a bifocal eyeglass frame. As shown in Figures 6 and 7, it is a transparent plate that is slightly higher than the height of the fabric lens to be fitted into the eyeglass frame. It has a tongue piece that holds the upper part of the frame, and also has a horizontal line that indicates the distance optical center and a horizontal line that indicates the limit of the far vision range, and has equally spaced scales that indicate the upper and lower heights as necessary. Disclosed are those featuring the following.

<Problems to be solved by the invention> In this way, in order to fit a progressive multifocal lens into an eyeglass frame, it is first necessary to check whether the eyeglass frame is an appropriate frame, and then The work was divided into parts, such as determining the layout position of the lens in the frame, which was inefficient.

Furthermore, the method of determining the pupil position based on photography and aligning the optical center as described in the above-mentioned Japanese Patent Publication No. 46-28958 has the problem that the work is complicated and requires large-scale equipment. Nakatsuta. In addition, in recent years, the 8th grade of progressive multifocal lenses has been developed.
As shown in the figure, lenses have been developed that have a ``progressive zone'' design in which the addition power gradually decreases from the near vision area to the lower area, and some lenses have improved the blur at the feet. Therefore, in order to make effective use of progressive multifocal lenses, it is necessary to have an accurate understanding of the blur beneath your feet.
When laying out a lens, it is preferable to lay out the lens after being familiar with the design characteristics of the lens, such as how the change value of the add power under the foot will be.

However, since it is not possible to grasp these numerical values during layout work, the only way to grasp changes in visual acuity under the feet is through adjusted glasses.

The present invention was made to solve such problems, and its purpose is to make it possible to lay out the desired glasses while checking whether the glasses frame is compatible with the progressive multifocal lens function, and to make it possible to An object of the present invention is to provide a frame-setting aid for a progressive multifocal lens in which layout information is written.

<Means for Solving the Problems> The object is to provide an auxiliary tool for fitting a progressive multifocal lens into an eyeglass frame, in which the distance center position and the near center position of the progressive multifocal lens are marked on a transparent sheet. A distance center layout hole and a near center layout hole are formed using the distance center layout hole as a reference point, a minimum distance viewing zone limit position display edge is formed upward from the distance center layout hole, and further the distance center layout A minimum near visual range limit position display line part and a power change display edge part are formed downward from the hole, and furthermore, a horizontal line of the geometrical center of the lens, a horizontal line and a vertical line of the distance center position, and a line from the geometrical center position of the lens are formed. Lens effective diameter display line,
This is achieved by a progressive focus lens framing aid characterized by drawing left and right frame display characters.

<Example> The present invention will be specifically explained below using the drawings.

FIG. 1 shows an embodiment of the present invention. This is entirely made of a transparent sheet, and the suitable material is a slightly thicker and more flexible plastic sheet.

The transparent plastic sheet 1 has a letter R2 drawn on it indicating the left and right sides of the lens frame, and the progressive multifocal fabric lens is centered at the intersection of two lines 3 and 4 whose extension lines are perpendicular to each other. A corresponding small circular distance eye point hole 5 is formed, and similarly, a small circular near eye point hole 6 whose center corresponds to the near center of the fabric lens is formed below the distance appointment hole 5. is formed. The center of this small circle 6 is slightly, for example, 2.5 mm to the right of the meridian 4. This is because the near vision passes through a point slightly closer to the nose than the distance vision. If the lens frame is on the left, it will of course be displaced to the left. Further, the diameter of the holes 5 and 6 is 4 mm in this example, and the reference diameter value is clearly specified so that the distance and near eye points of the actual lens are located within this diameter. This is based on the size of the pupil diameter, and since increasing the diameter causes an error in finding the center of the pupil at the center of the small circle 5, 4 mm is set as the optimum diameter. Further, the shape and size of the holes 5 and 6 are not particularly limited to circles, and can be set arbitrarily as long as they clearly indicate the eye point position. Furthermore, the straight edge 7 of the plastic sheet 1 can be seen above the small circular hole 5, but this position is at the limit where it would be inconvenient for distance vision work if there was no lens from the distance eye point to this position. , that is, it indicates the minimum necessary distance viewing range limit.

In this embodiment, this limit value is set to 13 mm, which is considered to be the optimum value based on experience, but the set value may vary depending on individual differences. Furthermore, a broken line 8 is drawn horizontally 22 mm below the distance eyepoint hole, indicating the minimum required near vision range limit. This setting value is also considered to be the optimum value based on experience, and the setting value can be set within a range of, for example, 18 mm to 30 mm depending on individual differences.

Next, a horizontal reference line 9 is drawn 2 mm below the distance eye point hole 5, which is the horizontal line at the geometric center of the lens, so that information such as the lens tilt when fitting the frame can be obtained. Further, 26 mm below this horizontal reference line 9 is the lower straight edge 10 of the plastic sheet 1, which in this example indicates the position where the addition power is reduced by 25%, and as described above. This is particularly useful in the case of the lens design shown in FIG. 8, and allows the degree of blur under the feet to be grasped numerically. In other words, the change in the addition power downward from the near eyepoint 6 shows a gradual decrease without an inflection point in order to improve the blur at the feet, as shown in Figure 8, so a constant decrease value is used as the index value. By indicating this as , the reduction value of the addition power can be known numerically.

Further, on the left side of the sheet 1, there is a lens diameter display section 11 in which 65φ, 70φ, 75φ, and 80φ are drawn and displayed on concentric circles corresponding to the lens diameters of general standard products centered on the geometric center. are arranged, and these curves 11 indicate the edge position corresponding to the ear side of the standard fabric lens. It is also possible to provide the sheet 1 with a gripping protrusion 12 if necessary. The sheet 1 of the present invention needs to be provided with indications or index values of these limit lines, and it goes without saying that the edges may be placed elsewhere and indicated by indication lines.

Next, we will discuss the second mode of use of the sheet 1.
This will be explained using FIGS. In the glasses frame 100,
For example, temporary lenses 101 and 10 made of transparent plastic.
2, and the sheet 1 of the present invention is temporarily attached thereon. The patient wears these glasses and is able to see directly into the distance. The person facing the user moves the seat 1 visually and adjusts it so that the center of the distance eye point hole 5, 5' coincides with the center of the pupil. If the patient can place a target, such as the letter E, in the correct direction of distance vision and adjust the letter so that the letter E is seen in one circle as shown in Fig. 3b instead of Fig. 3a, then the patient's eyes will be This means that the distance line of sight has correctly aligned with the center of the distance eyepoints 5 and 5'. If the near vision target appears in the same circle when the wearer performs near vision, then the near vision of both eyes passes correctly through the center of the near eyepoints 6 and 6'. It turns out. In this way, it is also possible to check the near vision. In addition, the centers of the near eyepoint holes 6, 6, and the near line of sight of both eyes cannot be matched, and the centers of the distance eyepoint holes 5, 5' and the distance line of sight of both eyes cannot be matched at the same time. If there is a slight difference between the two, match the lens to the more important one, since the fabric lens itself is fixed. For example, if you have presbyopia with emmetropia, the distance lens will be a glass plate with zero power, so the center of distance vision will be of very little importance, so the near eye point hole 6,
The emphasis should be placed on matching 6' and the near line of sight. The grip portion 12 is provided to smoothly move the sheet 1 during such adjustment. Although it may be a little different, it is possible to easily check the suitability of the eyeglass frame to be worn in the process of adjusting the correspondence between the perspective line of sight and the perspective center. For example, as shown in FIG. 4, the upper edge 7 of the sheet 1 is
is over the frame 103 or is outside the frame, and/or the lower edge 10 is the temporary lens 10
If it protrudes from the lower edge of the temporary lenses 101, 102, the eyeglass frame is too small and inappropriate, and on the other hand, as shown in FIG. If it protrudes to the side, this type of fabric lens is too small and you should either use a larger-diameter type of fabric lens, or choose a frame that allows for a slightly smaller lens. In this way, by simulating the layout in correspondence with the pupil position in a situation where the eyeglass frame is worn, it is possible to select an appropriate lens diameter and an appropriate eyeglass frame.

As described above, mark the centers of the distance eye point hole and near eye point hole on the temporary lenses 101 and 102 for which the adjustment of the auxiliary device has been completed, or paste this sheet to mark the distance center of the actual lens. If you process the border according to the layout so that the center of the near lens matches the mark and fit it into the eyeglass frame, you have completed the correct installation of the fabric lens into the eyeglass frame.

<Operations and Effects of the Invention> As described above, by using the auxiliary tool of the present invention, it is extremely easy to correctly frame bifocal lenses without the need for complicated operations using other complicated and sophisticated machines. It can be performed. In other words, it is possible to judge whether the desired eyeglass frame is compatible with the lens function desired by the wearer, and if it is not compatible, to provide information on the compatible lens diameter or eyeglass frame, and to further improve the quality of the processed lens. It is possible to check whether the processing is done according to the correct layout or to check the near vision.

In addition, since the degree of blur and the visual acuity value under the feet can be recognized at the time of layout, if a strong addition power is absolutely required, the degree of inconvenience can be reduced as much as possible within the range suitable for the purpose of use, and the nature of the unavoidable inconvenience can be reduced. The degree can be recognized correctly. Moreover, since this auxiliary tool is extremely simple and inexpensive, its utility value is great.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the auxiliary device of the present invention;
FIG. 2 is a front view showing how the auxiliary tool of Example 1 is used, FIGS. 3a and 3b are images showing whether the auxiliary tool has been adjusted to the correct position, and FIG. 3a is incorrect. Figure 3b is a diagram showing a correct example, Figures 4 and 5 are diagrams to show the suitability of the eyeglass frame itself, Figure 6 is a front view showing an auxiliary device according to the conventional technology, and Figure 7 is a diagram showing a correct example. Diagram showing the usage state of the assistive device, No. 8
The figure shows a progressive multifocal lens. 1...Transparent sheet of the aid, 2...Left and right frame display characters, 3...Horizontal line for distance center position, 4...Vertical line for distance center position, 5...Distance eye point hole, 6...
...Near eye point hole, 7...Minimum distance visual range limit position display edge, 8...Minimum near visual range limit position display line, 9...Geometric center horizontal line, 10...Power change display edge Edge, 11... Lens diameter display section, 12...
Gripping protrusion, 100...Eyeglass frame, 101, 10
2...Temporary lens.

Claims (1)

[Scope of utility model registration request] This is an auxiliary tool for fitting a progressive multifocal lens into an eyeglass frame, and the transparent sheet has a center layout hole for distance vision and a center layout hole for near vision using the distance vision center position and the near vision center position of the progressive multifocal lens as reference points. A center layout hole is formed, a minimum distance visual range limit position indicating edge is formed upward from the distance center layout hole, and a minimum near distance visual range limit position display line is formed downward from the distance center layout hole. forming a power change display edge with a geometric center horizontal line of the lens;
A frame setting aid for a progressive focus lens, characterized by drawing horizontal and vertical lines at the distance center position, a lens effective diameter display line from the lens geometric center position, and left and right frame display characters.