JP2011121214A - Method for manufacturing plastic spectacle lens, lens manufactured by the same, and matrix for spectacle lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a plastic spectacle lens that solves a problem arising in regard to the peripheral edge of the lens when manufacturing the spectacle lens by molding. <P>SOLUTION: A first mold 12 of circular outer peripheral shape having a first lens surface molding surface 15 for forming the object side front face of the lens of meniscus shape with positive dioptric power, and a second mold 13 of circular outer peripheral shape having a second lens surface molding surface 17 for forming the eyeball side rear face of the lens, are arranged facing with a predetermined space, and the outer peripheries of the first and second molds 12, 13 are surrounded with an adhesive tape 14 to form a lens matrix. Recesses 16 are formed at the peripheral edge of the first lens surface molding surface 15, in positions opposed by 180°. An injection needle is stuck into the adhesive tape 14 to fill the inside of a cavity with a molding material for molding the lens, and heating is carried out to obtain the lens formed with bulging parts corresponding to the recesses 16 at the edge side parts. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a plastic spectacle lens molded using a mold, a lens manufactured by the manufacturing method, and a mother mold for spectacle lenses.

  2. Description of the Related Art Conventionally, there is known a molding method in which a lens is molded by filling a thermosetting plastic material (monomer) as a liquid molding material for lens molding into a cavity of a lens molding matrix. Patent document 1 is shown as an example of such a molding method. In Patent Document 1, as shown in FIGS. 1 and 2, first and second molds 12 and 13 (molds) are attached to a gasket 14 as a holding member to form a mother die, and formed on the gasket 14. A liquid thermosetting plastic material is injected into the inside through the filling port 16 and cured to obtain a plastic lens. Alternatively, instead of using such a gasket, the adhesive tape 4 is used as a holding member in a state where two molding dies 1 and 2 (molds) face each other with a predetermined distance between the surfaces on which the lens is molded as in Patent Document 2. There are cases where a mother mold is constructed.

JP 2006-341538 A JP 2003-231135 A

In these conventional molding methods, there are some problems particularly when molding a meniscus plus lens having a thickness that decreases from the center to the edge.
First, as shown in FIG. 1 of Patent Document 1, in order to make the center thin in the case of molding a lens with a plus power that becomes thicker in the center when the thermosetting plastic material is filled from the filling port 16 on the side surface of the gasket 14. However, since the molds 12 and 13 are brought closer to each other, the gap between the edges becomes narrow, and it becomes difficult to provide the filling port 16. For this reason, there is a problem in that the plus lens is difficult to be thinly formed in the mother die of the type as in Patent Document 1. On the other hand, Patent Document 2 suggests that a part of the edge of the mold 1 is cut out to partially provide a large opening area on the side surface, and the injection needle 7 is pierced as an injection port to inject a plastic material. Yes. For this reason, if a mother die of the type as described in Patent Document 2 is used, it becomes possible to form the plus lens near the center thinly.
However, forming the thin lens near the center of the plus lens makes the edge of the lens very thin and easily breaks. In particular, such a defect such as cracking or chipping is likely to occur at the time of releasing from the mother die. If the edge becomes too thin, for example, as shown in FIG. 13, it is difficult to hold the opposing edge position of the spectacle lens L with fingers, and handling regarding transportation of the lens after molding becomes inconvenient. For example, when fixing the lens edge with a jig during transportation, if a force is applied to a portion where the lens edge is thin, it will be easily broken.
Further, in the case of molding a meniscus minus lens whose edge is thicker than the center, there is no problem like a plus lens. However, in the minus lens, the edge portion that is actually cut as an unnecessary portion in the frame is unnecessarily thick, so the material cost is increased.
The present invention has been made paying attention to such problems existing in the prior art. The object is to provide a plastic spectacle lens manufacturing method for solving the problems that occur with respect to the periphery of a lens when a meniscus lens is manufactured by molding, a lens manufactured by the manufacturing method, and a spectacle lens matrix Is to provide.

In order to solve the above-mentioned problem, in the invention according to claim 1, a circular outer peripheral shape having a first lens surface molding surface for molding a surface on the object side of a lens having a meniscus shape plus power or mixed power. And a second mold having a second lens surface molding surface having a circular outer peripheral shape for molding a back surface on the eyeball side of the lens, and a lens surface molding surface for both the lenses. Is held so as to face each other at a predetermined interval, and the lens mold is formed by surrounding the lens mold frames along the outer periphery thereof by the holding member, and having a cavity corresponding to the lens shape. A plurality of notch-like smooth surfaces are locally formed on the first lens surface molding surface of the mold of the mold at intervals at an edge position adjacent to the holding member, and a part of the holding member is formed. After filling the cavity with a molding material for lens molding from the formed injection port, the external material is applied to cure the molding material, so that it corresponds to the smooth surface at the edge portion that does not engage in vision correction on the back surface of the lens The gist of the invention is to obtain a lens having a bulged portion.
According to a second aspect of the present invention, in addition to the configuration of the first aspect of the invention, the injection port is formed at a position facing one of the plurality of smooth surfaces.
According to a third aspect of the invention, in addition to the configuration of the first or second aspect of the invention, the smooth surface extends in a band shape along the circumferential direction of the first mold, and the first lens surface molding surface is provided. The gist of the present invention is that the boundary line with the reference surface is a curve having a smaller curvature than the curvature of the outer periphery of the first mold.
The gist of the invention of claim 4 is that, in addition to the structure of any one of claims 1 to 3, the smooth surface is formed at two opposing locations across the center.
Further, in the invention of claim 5, in addition to the structure of any one of claims 1 to 4, if the lens thickness to be molded is not rotationally symmetric, it bulges in the direction to be in the vertical direction when the lens is used The gist is that the relative positions in the circumferential direction of the first and second molds are determined so that the portion is formed.

In the invention of claim 6, a first mold having a circular outer peripheral shape having a first lens surface molding surface for molding a surface on the object side of a lens having a meniscus negative power or mixed power, A holding member and a second mold having a second lens surface molding surface having a circular outer peripheral shape for molding the rear surface on the eyeball side of the lens are opposed to each other at a predetermined interval. The lens mold having a cavity corresponding to the lens shape is configured by holding and enclosing the both lens molds along the outer periphery thereof by the holding member, and the first lens of the first mold On the surface molding surface, a plurality of bulging portions are locally formed at intervals at an edge position adjacent to the holding member, and a lens molding lens is formed from an injection port formed in a part of the holding member. After the mold material is filled in the cavity, the lens is cured to form a notch-like smooth surface corresponding to the bulging portion at a marginal portion that is not involved in vision correction on the back surface of the lens. The gist is what we have obtained.
According to a seventh aspect of the invention, in addition to the configuration of the sixth aspect of the invention, the bulging portion extends in a belt shape along the circumferential direction of the first mold, and a reference surface of the first lens surface molding surface The boundary line is a curve having a smaller curvature than the curvature of the outer periphery of the first mold.
Further, in the invention of claim 8, in addition to the structure of the invention of claim 6 or 7, when the bulging portion is formed in two places across the center, and the lens thickness to be molded is not rotationally symmetric, The gist of the invention is that the relative positions of the first and second molds in the circumferential direction are determined so that a smooth surface is formed in a direction that should be in the vertical direction when the lens is used.

Further, in the invention of claim 9, in addition to the structure of the invention of claim 5 or 8, when the lens to be molded is a progressive power lens, the lens is formed by the first lens surface molding surface of the first mold. The gist is that the progressive refractive surface is formed.
In the invention of claim 10, in addition to the structure of the invention of claim 5 or 8, when the lens to be molded is a bifocal lens, the first lens surface molding surface of the first mold is used to form a The gist is that the focal lens surface is molded.
According to an eleventh aspect of the invention, in addition to the configuration of the invention according to any one of the fifth, eighth, ninth, or tenth aspects, the second lens of the second mold when the lens to be molded is an astigmatism correcting lens. The gist is that the toric surface or the toric surface of the lens is molded by the surface molding surface.

The gist of the invention of claim 12 is to produce a plastic spectacle lens by the method of any one of claims 1 to 11.
In the invention of claim 13, the first lens surface molding surface having a circular outer peripheral shape used for molding the object-side surface of the meniscus-shaped plus power or mixed power lens. A mold and a second mold having a second lens surface molding surface having a circular outer peripheral shape for molding the back surface on the eyeball side are arranged to face each other at a predetermined interval, and both lens surface molding surfaces are formed by a holding member. In the spectacle lens matrix having a cavity corresponding to the lens shape by surrounding both lens molds along the outer periphery thereof by holding the lens so as to face each other at a predetermined interval. The gist is to form a plurality of notched smooth surfaces locally at intervals at the edge positions adjacent to the holding member of the surface molding surface.
Further, the invention of claim 14 is characterized in that, in addition to the configuration of the invention of claim 13, the smooth surface is formed at two opposing positions across the center.
Further, in the invention of claim 15, in addition to the structure of the invention of claim 13 or 14, when the lens thickness to be molded is not rotationally symmetric, the bulge is formed in the direction to be in the vertical direction when the lens is used. The gist is that the relative positions in the circumferential direction of the first and second molds are determined so as to be formed.

In the structure like Claims 1-5 and Claims 13-15, several notch-like smooth surfaces are locally provided in the edge position adjacent to a holding member on the 1st lens surface molding surface of a 1st mold. Since it is formed, a portion near the edge that does not participate in the correction of visual acuity on the back surface of the lens by filling and curing the molding material for lens molding into the cavity of the lens master mold having such a first mold In addition, a meniscus spectacle lens having a plus power or a mix power can be obtained in which a bulging portion corresponding to the smooth surface is formed.
Then, when a lens with a thin plus power near the center of the lens is molded by such a method, even if the thickness of the edge is thin, a plurality of bulges formed at the edge near the edge of the lens that are not involved in vision correction. Since it can be set as the position which supports a protruding part with a finger, the handling becomes easy.
Here, the spectacle lens is a lens in which a predetermined lens power is set, but is not processed into a frame shape. Here, the mix frequency refers to a case where the frequencies in the strong main meridian direction and the weak main meridian direction are plus and minus, respectively.

In this case, it is preferable that the position of the injection port is formed at a position facing one of the smooth surfaces. As a result, even if the first and second molds facing each other approach and the distance between the edges of both molds becomes narrow, the space for the smooth surface is ensured. A molding material can be injected.
The smooth surface extends in a belt shape along the circumferential direction of the first mold, and the boundary line with the reference surface of the first lens surface molding surface is a curve with a smaller curvature than the curvature of the outer periphery of the first mold. It is preferable. In other words, the smooth surface extends in a strip shape along the circumferential direction of the first mold, and the boundary line has a curvature smaller than the curvature of the outer periphery of the first mold, so the tip side gradually tapers and is a kind of crescent shape. The smooth surface is formed. If the smooth surface has such a shape, it will be connected relatively smoothly to the reference surface of the first lens surface molding surface, and if this lens is used to mold the lens, it will be formed in a concave-convex relationship on the lens side. The bulging portion is also connected to the lens back surface relatively smoothly.
When the first lens surface molding surface 15 is processed by a processing device such as a grinding device, the first lens surface molding surface is processed to form the reference surface after the smooth surface is processed first. Is preferable in order to obtain a clean molding surface.

The smooth surfaces are preferably formed at two opposing positions across the center (even when three or more smooth surfaces are formed). The facing positions do not necessarily have to be exactly 180 degrees facing each other. This is because, by forming the smooth surface at such a position, the balance of the bulged portion of the molded lens is improved when it is sandwiched between fingers.
In addition, when the lens thickness to be molded is not rotationally symmetric, the relative circumferential direction of the first and second molds is such that the smooth surface is formed in the direction that should be the vertical direction when the lens is used. It is preferable to determine the correct position. Specific examples of the lens thickness not being rotationally symmetric include a progressive power lens, a bifocal lens, an astigmatism power correcting lens, and a prism-containing lens. Since these are not rotationally symmetric, they are lenses that have a fixed orientation when framed. On the other hand, when considering the shape and movement of the eyes, a general lens has a large lens effective area in the left-right direction and a small vertical direction. That is, since the lens shape is generally longer in the left-right direction, it is preferable to dispose the bulging portion in a region near the upper and lower edges because the lens effective region is not eroded. Therefore, a smooth surface is formed on the first mold in a direction that should be in the vertical direction when the lens is used.
In the astigmatism power correcting lens, the mold for forming the toric surface or the toric surface is the second mold, and it is preferable to form the mold by the second lens surface molding surface. Since the astigmatic axis direction is not constant, the toric surface or the toric surface is preferably set on the side where the notched smooth surface is not formed, that is, on the second mold side.
On the other hand, the progressive power lens, the progressive refractive surface of the bifocal lens, and the bifocal lens surface have a constant direction, and therefore, it is preferable to mold the first lens surface molding surface of the first mold.

  In the configuration as in the sixth to eighth aspects, since the plurality of bulging portions are locally formed at the edge position adjacent to the holding member on the first lens surface molding surface of the first mold. A notch corresponding to the bulging portion is formed in a portion close to the edge that is not involved in visual acuity correction on the back surface of the lens by filling a molding material for molding the lens into the cavity of the lens mold provided with the first mold and curing it. Meniscus-shaped spectacle lens having a smooth surface with a negative power or mixed power can be obtained. As a result, the amount of material used in the marginal portion that is not involved in the vision correction can be reduced, resulting in a reduction in raw material costs.

In this case, the injection port is preferably formed at a position facing one of the bulging portions. The vicinity where the material is injected is a portion where the material is ejected vigorously, so that the material is difficult to uniformly mix and is difficult to obtain a stable refractive index. For this reason, it is preferable to form the injection port at such an originally deformed position separated from the effective lens region as much as possible.
The bulging portion extends in a band shape along the circumferential direction of the first mold, and the boundary line with the reference surface of the first lens surface molding surface is a curve having a smaller curvature than the curvature of the outer periphery of the first mold. It is preferable that That is, the bulging portion extends in a band shape along the circumferential direction of the first mold, and the boundary line has a curvature smaller than the curvature of the outer periphery of the first mold, so the tip side gradually tapers and is a kind of crescent. A bulge portion having a shape is formed. If the bulging part has such a shape, it will be connected relatively smoothly to the reference surface of the first lens surface molding surface, and if this lens is used to mold the lens, it will be formed in a concave-convex relationship on the lens side. The cut-out smooth surface is connected to the lens back surface relatively smoothly.
It is preferable that the bulging portions are formed at two opposing positions across the center (even when three or more bulging portions are formed). The facing positions do not necessarily have to be exactly 180 degrees facing each other. Further, when the lens thickness to be molded is not rotationally symmetric as in the plus lens, it is preferable to form the bulging portion in the direction that should be the vertical direction when the lens is used.

In the above, glass, an alloy, etc. are common as a mold material.
Further, it is generally assumed that a thermosetting plastic is used as a molding material for lens molding. Examples of thermosetting plastics include allyl, urethane, thiourethane, and episulfide plastics. It is also envisaged to use a thermoplastic such as polycarbonate.
In order to cure the thermosetting plastic, heat, light, or microwave energy is passively polymerized and cured. In the case of thermoplastic plastic, plastic melted by heat is injected.

  In the above-described inventions according to claims 1 to 5 and claims 12 to 15, when the plus lens is thinly formed near the center, it is possible to secure a gripping portion even if the edge portion of the lens is very thin. This makes it easy to handle the lens. According to the sixth to eighth aspects of the present invention, the raw material cost can be reduced in the minus lens. Further, in the inventions of claims 9 to 11, since the lens characteristics are set on a preferable surface side for applying the present invention to each more specific lens whose lens thickness is not rotationally symmetric, the above-described effects are surely imparted. It becomes possible.

It is the 1st mold used for the mother mold of Examples 1-3 of the present invention, (a) is a sectional view of an AA line direction of Drawing 2, (b) is a BB line of Drawing 2. Sectional drawing of a direction. The top view of the same 1st mold. Sectional drawing of the 2nd mold used for the mother die of Examples 1-3 of the present invention. (A) And (b) is explanatory drawing explaining the method to construct | assemble a mother die by hold | maintaining a 1st and 2nd mold with an adhesive tape at predetermined intervals. Explanatory drawing explaining the method of injecting a plastic material by piercing an injection needle into a mother mold in Examples 1-3 of the present invention. (A) of the positive power lens shape | molded by the method of Examples 1-3 of this invention is a perspective view, (b) is sectional drawing in CC line of (a). It is the 1st mold used for the mother die of Example 4 of the present invention, Comprising: (a) is a sectional view of the DD line direction of Drawing 8, (b) is the EE line direction of Drawing 2. Sectional drawing. The top view of the same 1st mold. Sectional drawing of the 2nd mold used for the mother die of Example 4 of the present invention. Explanatory drawing explaining the method of inject | pouring a plastic material by piercing an injection needle in a mother die in Example 4 of this invention. (A) of the minus power lens shape | molded by the method of Example 4 of this invention is a perspective view, (b) is sectional drawing in the FF line of (a). (A) of the positive power bifocal lens shape | molded in the other Example of this invention is a perspective view, (b) is sectional drawing in the GG line of (a). Explanatory drawing explaining an example of the holding method at the time of hold | maintaining the shape | molded spectacle lens with a finger | toe.

Hereinafter, a specific method for producing a plastic spectacle lens of the present invention will be described with reference to the drawings.
Example 1
In the first embodiment, a single vision lens of S + 2.00D is molded using the mother die 11. The lens used was a material with a refractive index of 1.6. The same applies to the following embodiments. First, the structure of the mother die 11 used for molding will be described.
As shown in FIG. 1 to FIG. 4, the plastic lens matrix 11 is composed of a first mold 12, a second mold 13, and an adhesive tape 14 as a holding member. As shown in FIG. 1 and FIG. 2, the first mold 12 is a meniscus glass circular plate whose front and back surfaces are made of spherical surfaces having a predetermined curve, and the concave surface is the first lens surface molding surface. It is set to 15. Crescent-shaped concave portions 16 serving as smooth surfaces are formed at two positions near the edge of the first lens surface molding surface 15 facing each other at 180 degrees. As shown in FIG. 3, the second mold 13 is also a meniscus glass circular plate whose front and back surfaces are made of spherical surfaces with a predetermined curve, and the convex surface side is a second lens surface molding surface 17. ing. The first and second molds 12 and 13 are held by an interval holding device (not shown), and the adhesive tape 14 is wound around the outer circumference as shown in FIGS. 4A and 4B while being held at a predetermined interval. Thus, the mother die 11 in which the cavity corresponding to the lens shape is formed is configured. Although the adhesive tape 14 is used as the holding member here, a gasket can also be used.
Then, as shown in FIG. 5, a thermosetting plastic material is filled into the cavity by an injection needle (not shown) with the position where the recess 16 is formed as an opening, and is cured according to a conventional method to form a lens.

Next, the shape characteristic of the first lens surface molding surface 15 of the first mold 12 and the shape characteristic of the second lens surface molding surface 17 of the second mold 13 will be described.
The first lens surface molding surface 15 of the first mold 12 is a surface for molding the convex surface side (object side) of the spectacle lens L to be molded. As shown in FIG. 1B, the first lens surface molding surface 15 is a curved surface having six curves in terms of 1.6 because the material refractive index of the lens is 1.6 in the first embodiment. Here, the 6 curve means that the surface refractive power is 6 dipter, and is obtained from the calculation of (material refractive index−1.0) / curvature radius = (1.6−1.0) /0.1=6. It is done. The same applies to other curves, and the relationship between the curve value and the radius of curvature is based on the same calculation formula.
As shown in FIG. 2, in the first embodiment, the concave portion 16 has a curved surface that forms a toric surface having two curves in the vertical direction and six curves in the horizontal direction when the concave portions 16 are arranged in the vertical direction. In the present embodiment, a portion of the first lens surface molding surface 15 excluding the concave portion 16 is defined as a reference surface BS, and a surface intersection line between the reference surface BS and the concave portion 16 is defined as a boundary line BL. The reference surface BS is a surface that forms an effective lens surface that expresses the lens power of the spectacle lens L to be formed. In other words, the surface of the recess 16 is obtained by synthesizing a surface having a shallower curve with respect to the surface formed by the curve of the reference surface BS, and giving a negative sag amount to the reference surface BS. Can do. The sag amount is a machining displacement amount with respect to the reference surface BS, and here, a case where the sag amount is displaced in a direction in which the curve becomes shallower is negative.
When the first lens surface molding surface 15 is processed by a processing device such as a grinding device, the concave portion 16 is first processed and then the first lens surface molding surface 15 is processed to obtain the reference surface BS. It is preferable. This is because if the processing order is reversed, the reference surface BS is easily scratched. In addition, forming the concave portion 16 as a toric surface does not require a free-form processing technique in processing, and can be performed by a conventional eyeglass lens processing apparatus, so that processing time is not reduced and the formation process of the concave portion 16 is reduced. Will be.
On the other hand, the second lens surface molding surface 17 of the second mold 13 is a surface for molding the convex surface side (object side) of the spectacle lens L to be molded. As shown in FIG. 3, the second lens surface molding surface 17 is a curved surface having a 4.08 curve in 1.6 conversion in the first embodiment. In Example 1, since the thickness changes equally in all directions from the center, the relative positions in the circumferential direction of both molds 12 and 13 may be any positions.
The spectacle lens L in which the bulging portion 18 corresponding to the concave portion 16 as shown in FIGS. 6A and 6B is formed by the mother die 11 using the first and second molds 12 and 13 as described above. Is done.

Table 1 shows the data of the spectacle lens L of the sample molded by changing the distance between the first and second molds 12 and 13 by the mother die 11 using the first and second molds 12 and 13. Is. In Example 1, the first and second molds 12 and 13 having a diameter of 80 mm were used.
Here, the “substantially effective size of the lens” refers to a size in a state in which the periphery of the molded product that has been released from the matrix 11 is unnecessary to form the spectacle lens L. The “lens center thickness” is a concept that changes depending on the effective effective size of the lens, and can be changed as appropriate. I tried to do it. Further, the “mold edge interval in the recess direction” is an interval in the direction in which the bulging portion 18 of the spectacle lens L to be molded is formed in the direction of the widest interval near the edge. On the other hand, “the mold edge interval other than the recess direction” is a direction in which the interval is closest to the edge and the narrowest.
As shown in these samples, although the interval gradually decreases as the size of the spectacle lens L to be molded becomes smaller at the “mold edge interval in the recess direction”, it is generally sufficient to pierce the injection needle. The interval will be maintained. On the other hand, “the mold edge interval other than the direction of the concave portion” is narrow when the center thickness is set as in the sample, and the inside of the cavity is curved, so that the injection needle cannot be sufficiently pierced. When the first mold in which the concave portion 16 is not formed is used, since the mold interval is narrow, the center thickness of the lens such as these samples cannot be molded, so the center thickness must be increased. In addition, the spectacle lenses L of these samples all have a bulging portion 18 having a sufficient thickness at the opposing position, and can be safely held without damaging the edges if the portion is sandwiched between fingers. It is convenient for handling related to later transportation. In addition, each sample has a very narrow mold edge other than the direction of the recess, and release from this direction is very difficult, but even in such a case, a sufficient thickness is ensured in the direction of the recess. When the mold is released, the mold can be released without inserting cracks around the molded product by inserting a release jig in the direction of the recess.

(Example 2)
In Example 2, a single vision lens having S + 1.00D, C + 2.00D, and AX180 astigmatism correction is molded using the mother die 11. The configuration of the mother die 11 used for molding is the same as in the first embodiment except that the shape characteristics of the second lens surface molding surface 17 of the second mold 13 are different, and only the shape characteristics will be described. .
The first mold 12 of the second embodiment has the same shape characteristics as the first embodiment. That is, the reference surface BS of the first lens surface molding surface 15 is a six-curved curved surface, and the concave portion 16 is a two-curved and six-curved toric surface. On the other hand, the second lens surface molding surface 17 of the second mold 13 is a toric surface having a 3.11 curve and a 5.11 curve. That is, a toric surface for correcting astigmatism is formed on the back surface of the spectacle lens L to be molded by the second lens surface molding surface 17.
In Example 2, the astigmatic axis of the spectacle lens L to be molded is 180 degrees. That is, in the state of use, the horizontal direction is the thickest direction of the lens and the vertical direction is thin. It is preferable for the purpose of the present invention to form the bulging portion 18 in the vertical direction where the thickness is reduced, and the vertical direction is more preferable because the effective lens area is reduced. Therefore, unlike Example 1, it is necessary to determine the relative positions in the circumferential direction of both molds 12 and 13 so that the concave portions 16 of the first mold 12 are arranged in the vertical direction. Further, since the astigmatism axis is not constant, the astigmatism correction surface is preferably molded by the second lens surface molding surface 17 of the second mold 13 in this way.
A spectacle lens L in which a bulging portion 18 corresponding to the concave portion 16 as shown in FIG. 5 is formed by the mother die 11 using the first and second molds 12 and 13 as described above.

  Table 2 shows the data of the spectacle lens L of the sample formed by changing the distance between the first and second molds 12 and 13 by the matrix 11 using the first and second molds 12 and 13. Is. Since the bulging portion 18 having a sufficient thickness is formed at the upper and lower opposing positions as in the first embodiment, it can be safely held without damaging the edge by pinching the portion with fingers, and transported after molding. It is convenient for the handling about etc. In particular, in the lens characteristics as in Example 2, when the invention is not applied, the edge in the vertical direction becomes thin and the portion is easily cracked. Since the direction edge can be thickened, the possibility of the lens edge being cracked or chipped becomes very low.

(Example 3)
In Example 3, it is assumed that a progressive-power lens having astigmatism correction with S + 1.00D, C + 2.00D, AX180, and addition 2.00D is molded using the mother die 11. Regarding the configuration of the mother die 11 used for molding, only the shape characteristics of the first lens surface molding surface 15 of the first mold 12 and the shape characteristics of the second lens surface molding surface 17 of the second mold 13 are different. Since the subsequent steps are the same as those in the first embodiment, only the shape characteristics will be described. In Example 3, no sample was prepared.
In the first lens surface molding surface 15 of the first mold 12 of Example 3, the reference surface BS is 6 curves at the distance eye point of the spectacle lens L to be molded, and the addition is 2.00 D. The concave surface 16 is a toric surface having 2 curves and 6 curves. Since the addition power is arranged in the vertical direction in use, the concave portion 16 needs to be formed at a position where the bulging portion 18 is formed in the vertical direction of the spectacle lens L to be molded.
On the other hand, the second lens surface molding surface 17 of the second mold 13 is a toric surface having a 3.11 curve and a 5.11 curve. That is, it has the same shape characteristics as in the second embodiment.
The astigmatic axis of the spectacle lens L to be molded also in Example 3 is 180 degrees. Therefore, it is necessary to determine the relative positions in the circumferential direction of both molds 12 and 13 so that the concave portions 16 of the first mold 12 are arranged in the vertical direction as in the second embodiment.
A spectacle lens L in which a bulging portion 18 corresponding to the concave portion 16 as shown in FIG. 5 is formed by the mother die 11 using the first and second molds 12 and 13 as described above.

Example 4
In Example 4, it is assumed that an S-4.00D single vision lens is molded using the mother die 31. In Example 4, the first mold 32 and the second mold 33 shown in FIGS. 7 and 9 are used. The first mold 32 is a meniscus glass circular plate whose front and back surfaces are made of spherical surfaces with a predetermined curve, and the concave surface is a first lens surface molding surface 35. Crescent-shaped bulging portions 36 are formed at two positions near the edge of the first lens surface molding surface 35 facing each other by 180 degrees. As shown in FIG. 8, the second mold 33 is also a meniscus glass plate having a predetermined curved surface on the front and back surfaces, and the convex surface side is a second lens surface molding surface 37. ing. As shown in FIG. 10, the first and second molds 32 and 33 are held in a gap holding device (not shown), and an adhesive tape 34 is wound around the outer periphery to form a cavity corresponding to the lens shape. 31 is constituted. Although the adhesive tape 34 is used as the holding member here, a gasket can be used.
Then, as shown in FIG. 9, the cavity is filled with a thermosetting plastic material with an injection needle (not shown) at the position where the bulging portion 36 is formed, and is cured by a conventional method to form a lens. Since a negative power lens is manufactured in the fourth embodiment, the width to which the injection needle is to be injected is sufficiently secured from any direction on the outer periphery of the mother die 31, but the bulging portion 36 that is a deformed portion. Is preferred.

The first lens surface molding surface 35 of the first mold 32 is a surface for molding the convex surface side (object side) of the spectacle lens L to be molded. As shown in FIG. 7, the first lens surface molding surface 35 is a curved surface having two curves in the fourth embodiment. As shown in FIG. 8, in the fourth embodiment, the bulging portion 3 has a curved surface that forms a toric surface having six curves in the vertical direction and two curves in the left and right directions when the bulging portion 36 is arranged in the vertical direction. Has been. In the present embodiment, the surface of the first lens surface molding surface 35 excluding the bulging portion 3 is defined as a reference surface BS, and the intersecting line of the surface between the reference surface BS and the bulging portion 3 is a boundary line BL. And The reference surface BS is a surface that forms an effective lens surface that expresses the lens power of the spectacle lens L to be formed. That is, the surface of the bulging portion 36 is obtained by synthesizing a part of a deeper curve with respect to the surface formed by the curve of the reference surface BS, and gives a positive sag amount to the reference surface BS. Can think.
When the first lens surface molding surface 35 is processed by a processing device such as a grinding device, the bulging portion 36 is processed first, and then the first lens surface molding surface 35 is processed to obtain the reference surface BS. It is preferable to obtain
On the other hand, the second lens surface molding surface 37 of the second mold 33 is a surface for molding the convex surface side (object side) of the spectacle lens L to be molded. The second lens surface molding surface 37 is a curved surface having six curves in the fourth embodiment. In Example 4, since the thickness changes equally in all directions from the center, the relative positions in the circumferential direction of both molds 32 and 33 may be any positions.
The spectacle lens L in which the concave portion 38 corresponding to the bulging portion 36 as shown in FIGS. 11A and 11B is formed by the mother die 31 using the first and second molds 32 and 33 is formed. Is done.

It should be noted that the present invention can be modified and embodied as follows.
In the second embodiment, the present invention can be applied even when the astigmatic axis is other than the horizontal direction.
-It is also possible to adapt about the case where there is no astigmatism power in Example 3.
-The shape of the recessed part 16 and the bulging part 36 is an example, Comprising: It is not limited above.
-It is also possible to apply to the production of a bifocal lens as shown in FIGS. 12 (a) and 12 (b). In this case, the bifocal surface (object-side surface) 41 needs to be molded by the first lens surface molding surface of the first mold.
-Besides, it is free to implement in a mode that does not depart from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 11, 31 ... Mother mold, 12, 32 ... 1st mold, 13, 33 ... 2nd mold, 14, 34 ... Adhesive tape as a holding member, 15, 35 ... 1st lens surface molding surface, 17, 37: Second lens surface molding surface, 16: Concave portion as a notch-shaped smooth surface, 36: Swelling portion, L: Eyeglass lens.

Claims (15)

A first mold having a circular outer peripheral shape having a first lens surface molding surface for molding a surface on the object side of a lens having a meniscus plus power or a mix power, and a back surface on the eyeball side of the lens. A second mold having a second lens surface molding surface having a circular outer shape for molding is held by a holding member so that both lens surface molding surfaces face each other at a predetermined interval. Constructing a lens matrix having a cavity corresponding to the lens shape by surrounding both lens molds along the outer periphery thereof,
A plurality of notched smooth surfaces are locally formed on the first lens surface molding surface of the first mold at intervals at an edge position adjacent to the holding member;
After filling the cavity with a molding material for lens molding from the injection port formed in a part of the holding member, the molding material is cured by applying external energy, and the edge of the lens is not involved in the vision correction. A method of manufacturing a plastic spectacle lens in which a lens having a bulging portion corresponding to the smooth surface is formed in a portion. 2. The method of manufacturing a plastic spectacle lens according to claim 1, wherein the injection port is formed at a position facing one of the plurality of smooth surfaces. The smooth surface extends in a strip shape along the circumferential direction of the first mold, and the boundary line with the reference surface of the first lens surface molding surface has a curvature smaller than the curvature of the outer periphery of the first mold. The method of manufacturing a plastic spectacle lens according to claim 1, wherein the plastic spectacle lens is a curved line. 4. The method for manufacturing a plastic spectacle lens according to claim 3, wherein the smooth surface is formed at two opposing positions across the center. When the lens thickness to be molded is not rotationally symmetric, the circumferential direction relative to the first and second molds is formed so that the bulging portion is formed in the direction to be the vertical direction when the lens is used. 5. The method for manufacturing a plastic spectacle lens according to claim 1, wherein the position is determined. A first mold having a circular outer peripheral shape having a first lens surface molding surface for molding a surface on the object side of a meniscus lens having a minus power or a mix power, and a back surface on the eyeball side of the lens. A second mold having a second lens surface molding surface having a circular outer shape for molding is held by a holding member so that both lens surface molding surfaces face each other at a predetermined interval. Constructing a lens matrix having a cavity corresponding to the lens shape by surrounding both lens molds along the outer periphery thereof,
A plurality of bulging portions are locally formed on the first lens surface molding surface of the first mold at intervals at an edge position adjacent to the holding member;
After filling the cavity with a molding material for lens molding from an injection port formed in a part of the holding member, the molding material is cured, and the bulge is formed at the edge portion that does not engage in visual acuity correction on the back surface of the lens. A method for producing a plastic spectacle lens in which a lens having a notch-like smooth surface corresponding to a protruding portion is obtained. The bulging portion extends in a band shape along the circumferential direction of the first mold, and the boundary line with the reference surface of the first lens surface molding surface is smaller than the curvature of the outer periphery of the first mold. 7. The method of manufacturing a plastic spectacle lens according to claim 6, wherein the curve is a curvature curve. The bulges are formed at two locations across the center, and when the lens thickness to be molded is not rotationally symmetric, a smooth surface is formed in the direction that should be up and down when the lens is used. The method for manufacturing a plastic spectacle lens according to claim 6 or 7, wherein a relative position in a circumferential direction of the first and second molds is determined. 9. The plastic according to claim 5, wherein when the lens to be molded is a progressive power lens, the progressive refractive surface of the lens is molded by the first lens surface molding surface of the first mold. A method for manufacturing an eyeglass lens. 9. The plastic according to claim 5 or 8, wherein when the lens to be molded is a bifocal lens, the bifocal lens surface of the lens is molded by the first lens surface molding surface of the first mold. A method for manufacturing an eyeglass lens. 10. The toric surface or the toric surface of a lens is molded by the second lens surface molding surface of the second mold when the lens to be molded is an astigmatism correcting lens. Or the manufacturing method of the plastic spectacle lens in any one of 10. The plastic spectacle lens manufactured by the method in any one of Claims 1-11. A first mold having a first lens surface molding surface having a circular outer peripheral shape used for molding a surface on the object side of a lens having a meniscus plus power or a mix power, and a back surface on the eyeball side A second mold having a second lens surface molding surface having a circular outer peripheral shape for molding the lens is arranged to face each other at a predetermined interval, and the lens surface molding surfaces are opposed to each other by a holding member at a predetermined interval. While holding, in the mother mold for spectacle lens having a cavity corresponding to the lens shape by surrounding both lens molds along the outer periphery by the holding member,
A spectacle lens matrix, wherein a plurality of notched smooth surfaces are locally formed at intervals at an edge position adjacent to the holding member of the first lens surface molding surface. 14. The mother-piece for spectacle lens according to claim 13, wherein the smooth surface is formed at two opposing positions across the center. When the lens thickness to be molded is not rotationally symmetric, the relative positions in the circumferential direction of the first and second molds so that the bulging portion is formed in the direction to be the vertical direction when the lens is used. The mother die for spectacle lenses according to claim 13 or 14, characterized in that is determined.

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