Spectacle lens production method and spectacle lens

Abstract

A method for producing a spectacle lens 2 including a base portion 2 that is made of a resin material and includes a convex object-side face and a concave eyeball-side face, and an optical element 12 that is made of a material different from the material for forming the base portion and is embedded in the base portion, is described. The method includes: arranging an optical element in a cavity 28 of a mold including a first mold part 20 and a second mold part 24 that can be opened and closed; introducing a resin material for forming a base portion of the spectacle lens into the cavity of the mold; obtaining the spectacle lens by curing the resin material that is a resin for forming the base portion; disassembling the mold; and detaching the spectacle lens from the mold.

Claims

1. A spectacle lens production method for producing a spectacle lens including a base portion that is made of a resin material and the base portion includes a convex object-side face and a concave eyeball-side face, and the spectacle lens includes an optical element that is made of a material different from the material for forming the base portion and is embedded in the base portion, the method comprising: providing the optical element so as to be arranged in a cavity of a mold including a first mold part and a second mold part that can be opened and closed; wherein the optical element is a plurality of small beads that are each made of a resin different from the resin for forming the base portion, and that are embedded in the base portion in a state of being partially exposed from the base portion, and the providing the optical element includes arranging resin material of the resin for forming the small beads by dropping to predetermined positions on a surface of the first mold part of the mold and first curing the resin material for forming the small beads; after providing the optical element, introducing a resin material for forming the base portion of the spectacle lens into the cavity of the mold; obtaining the spectacle lens by second curing the resin material that is a resin for forming the base portion; disassembling the mold; and detaching the spectacle lens from the mold.

2. The spectacle lens production method according to claim 1, wherein each of the small beads has a refractive power larger than that of the base portion.

3. The spectacle lens production method according to claim 1, wherein the small beads each have a diameter r of 0.8 to 2.0 mm.

4. The spectacle lens production method according to claim 1, wherein at least one of the small beads are made of a thiourethane material.

5. The spectacle lens production method according to claim 1, wherein the refractive power of at least one of the small beads is larger than the refractive power of the base portion by 2.00 to 5.00 diopters.

6. The spectacle lens production method according to claim 1, wherein intervals between adjacent small beads are each set to a distance that is equal to a radius (r/2) of the small beads.

7. The spectacle lens production method according to claim 1, wherein the base portion has a refractive power that corrects short-sightedness.

8. The spectacle lens production method according to claim 1, wherein at least one of the small beads are hemispherical.

9. The spectacle lens production method according to claim 1, wherein the resin for forming the base portion is a thermosetting resin.

10. The spectacle lens production method according to claim 1, wherein at least one of the small beads are embedded in the base portion and have a surface being flush with the convex object-side face of the base portion and at least one of the small beads are exposed to the outside of the base portion from the convex object-side face.

11. The spectacle lens production method according to claim 1, wherein the spectacle lens has a hard coat layer on the object-side face.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a schematic plan view of a spectacle lens produced using a spectacle lens production method according to an embodiment of the present disclosure.

(2) FIG. 2 is a schematic cross-sectional view of the spectacle lens produced using the spectacle lens production method according to the embodiment of the present disclosure.

(3) FIG. 3 is a flowchart illustrating steps of the spectacle lens production method according to the embodiment of the present disclosure.

(4) FIG. 4 is a schematic view illustrating the spectacle lens production method shown in FIG. 3.

(5) FIG. 5 is a schematic view illustrating the spectacle lens production method shown in FIG. 3.

(6) FIG. 6 is a schematic view illustrating the spectacle lens production method shown in FIG. 3.

(7) FIG. 7 is a schematic view illustrating the spectacle lens production method shown in FIG. 3.

(8) FIG. 8 is a schematic view illustrating the spectacle lens production method shown in FIG. 3.

(9) FIG. 9 is a schematic perspective view of a spectacle lens produced using a spectacle lens production method according to a second embodiment of the present disclosure.

(10) FIG. 10 is a cross-sectional view taken along the line X-X in FIG. 1.

(11) FIG. 11 is a flowchart illustrating steps of the second spectacle lens production method according to the present disclosure.

(12) FIG. 12 is a schematic view illustrating the spectacle lens production method shown in FIG. 11.

(13) FIG. 13 is a schematic view illustrating the spectacle lens production method shown in FIG. 11.

(14) FIG. 14 is a schematic view illustrating the spectacle lens production method shown in FIG. 11.

(15) FIG. 15 is a schematic view illustrating the spectacle lens production method shown in FIG. 11.

(16) FIG. 16 is a schematic view illustrating the spectacle lens production method shown in FIG. 11.

(17) FIG. 17 is a schematic cross-sectional view of a spectacle lens produced using a spectacle lens production method according to a third embodiment of the present disclosure.

(18) FIG. 18 is a schematic view illustrating a method for producing the spectacle lens shown in FIG. 17.

(19) FIG. 19 is a schematic view illustrating the method for producing the spectacle lens shown in FIG. 17.

(20) FIG. 20 is a schematic view illustrating actions of the spectacle lens shown in FIG. 17.

DESCRIPTION OF EMBODIMENT

(21) Hereinafter, a spectacle lens production method according to a first embodiment of the present disclosure will be described in detail with reference to the drawings. FIG. 1 is a schematic plan view of a spectacle lens 1 produced using a spectacle lens production method according to a first embodiment of the present disclosure, and FIG. 2 is a schematic cross-sectional view of the spectacle lens 1.

(22) As shown in FIGS. 1 and 2, the spectacle lens 1 includes a spectacle lens main body (base portion) 2. The spectacle lens main body (base portion) 2 includes a convex object-side face (outer face) 4 and a concave eyeball-side face (inner face) 6. Moreover, in this embodiment, a hard coat layer 8 and an anti-reflection coating (AR coating) 10 are provided on the object-side face 4.

(23) On the object-side face 4 side of the spectacle lens main body 2, a large number of hemispherical small beads (optical elements) 12 are embedded in the spectacle lens main body 2. As shown in FIG. 1, the small beads 12 are regularly arranged in a ring-like region at the center of the spectacle lens main body 2 in a plan view. Moreover, as shown in FIG. 1, when viewed in a cross-section, part of each small bead 12, specifically, a flat portion 12a is flush with the convex object-side face 4 of the spectacle lens main body 2 and is exposed to the outside.

(24) Also as described in Patent Document 1 above, it is known that the use of spectacle lenses in which a large number of small beads are embedded can suppress the progress of refractive errors such as short-sightedness of a person who is wearing the glasses. The principle thereof, which will be described later in detail, is that small beads having a refractive power larger than that of the base portion of the spectacle lens for correcting short-sightedness form images also in front of the retina, and suppress the progress of short-sightedness. It is preferable that the refractive power of the small beads is larger than the refractive power of the base portion of the spectacle lens by 2.00 to 5.00 diopters.

(25) In this embodiment, the spectacle lens main body 2 is made of, for example, a thiourethane-based resin (thermosetting resin) with a refractive index of approximately 1.590 or 1.578. Furthermore, the small beads 12 are made of, for example, a thiourethane-based resin (thermosetting resin) with a refractive index of approximately 1.5955 and having excellent adhesion to the resin for forming the spectacle lens main body 2. The resin for forming the spectacle lens main body 2 and the resin for forming the small beads 12 may also be other types of thermosetting resins selected as appropriate in consideration of refractive indices.

(26) Furthermore, in this embodiment, the hemispherical small beads 12 are set to each have a diameter r of approximately 0.8 to 2.0 mm and a thickness of approximately 0.1 to 1.15 mm. Furthermore, it is preferable that the intervals between the small beads 12 are each set to be approximately equal to the radius (r/2) of the small beads 12.

(27) Next, a production method of the spectacle lens 1 will be described.

(28) First, a first mold part 20 that is used to produce the spectacle lens 1 is prepared (S1). The first mold part 20 is made of a material such as glass as in the case of known mold parts that are used to produce plastic spectacle lenses, and includes a concave molding face 22 for molding the convex object-side face 4 of the spectacle lens 1 as shown in FIG. 4.

(29) Next, as shown in FIG. 5, a predetermined amount of resin material (a raw material monomer M2) that is a resin for forming the small beads 12 is arranged (dropped) using a dispenser, at each predetermined position on the concave molding face 22 of the first mold part 20 (S2). Each droplet of raw material monomer M2 has a substantially hemispherical (plano-convex lens) shape on the molding face 22 due to surface tension or the like. The viscosity, amount, and the like of the raw material monomer M2 arranged on the molding face 22 are set such that the arranged raw material monomer M2 is cured to form small beads 12 with a desired size and shape.

(30) Next, the hemispherical raw material monomer M2 dropped on the molding face 22 is cured (S3). According to the production method of this embodiment, the dropped raw material monomer M2 is cured by being left at room temperature for a predetermined period of time. However, the raw material monomer M2 may be cured with heat or the like according to the type of raw material monomer, the treatment environment, or the like.

(31) Moreover, as shown in FIG. 6, the first mold part 20 in which the raw material monomer M2 dropped on predetermined positions on the molding face 22 has been cured is combined with other mold parts 24, 25, and the like, so that a mold 26 is assembled, and a cavity 28 inside the mold 26 is closed (S4). At this time, the molding face 22 of the first mold part 20 constitutes part of the cavity 28 (FIG. 6).

(32) Next, as shown in FIG. 7, a raw material monomer (resin material) M1 for forming the spectacle lens main body 2 is poured, that is, introduced into the cavity 28 (S5). At this time, the raw material monomer M2 for forming the small beads 12 has been cured at predetermined positions on the molding face 22 of the first mold part 20 and has formed the small beads 12, and thus the small beads 12 are taken into the raw material monomer M1 introduced into the cavity 28 and forming the spectacle lens main body 2.

(33) Moreover, the raw material monomer (resin material) M1 introduced into the cavity 28 and forming the spectacle lens main body 2 is cured in the cavity 28 through heating to a predetermined temperature (S6). As a result, a spectacle lens in which the small beads 12 are embedded in the spectacle lens main body 2 is formed inside the cavity 28. The faces of the small beads 12 that are in contact with the molding face 22 are flush with the object-side face 4 of the spectacle lens main body 2 that is in contact with the molding face 22, and the small beads 12 are exposed to the outside from the spectacle lens main body 2 at these portions (flat portions 22a).

(34) Lastly, the mold 26 is disassembled, and the spectacle lens 1 molded inside the cavity 28 is detached, that is, released from the mold 26 (S7).

(35) Subsequently, the hard coat layer 8 and the anti-reflection coating 10 are formed on a convex face 3 of the spectacle lens main body 2, so that the spectacle lens 1 is finally completed.

(36) In the foregoing first embodiment, thermosetting resins were used as the resins for forming the spectacle lens main body and the small beads, but a configuration may also be employed in which thermoplastic resins commonly used for spectacle lenses are used instead of the thermosetting resins.

(37) Furthermore, in the foregoing first embodiment, the first mold part 20 includes the concave molding face 22 for molding the convex object-side face 4 of the spectacle lens 1, and the convex object-side face 4 of the spectacle lens is molded by the concave molding face 22, but a configuration may also be employed in which a first mold part includes a convex molding face for molding a concave eyeball-side face of a spectacle lens, and the concave eyeball-side face of the spectacle lens is molded by the convex molding face.

(38) Next, a spectacle lens production method according to a second embodiment of the present disclosure will be described in detail.

(39) First, the configuration of a spectacle lens produced using the spectacle lens production method according to the second embodiment of the present disclosure will be described. FIG. 9 is a schematic perspective view of a spectacle lens 1 produced using the spectacle lens production method according to the second embodiment of the present disclosure, and FIG. 10 is a cross-sectional view taken along the line X-X in FIG. 9.

(40) As shown in FIGS. 9 and 10, the spectacle lens 1 includes a spectacle lens main body 202. The spectacle lens main body 202 is made of a thermosetting resin, and includes a convex object-side face 204 and a concave eyeball-side face 206.

(41) In the spectacle lens main body 202, a strip-like diffraction grating 208 that is an optical element is embedded in the spectacle lens main body 202. As shown in FIG. 9, the diffraction grating 208 is arranged at a position offset from the center of the spectacle lens main body 202 and extends in the radial direction in a plan view. Moreover, as shown in FIG. 2, the diffraction grating 8 as viewed in a cross-section is arranged so as not to be exposed to the outside from the object-side face (outer face) 204 and the eyeball-side face (inner face) 206 of the spectacle lens main body 202, that is, so as to be completely surrounded by the resin for forming the spectacle lens main body 202.

(42) Next, a production method of the spectacle lens 201 will be described.

(43) First, a first mold part 220 that is used to produce the spectacle lens 201 is prepared (S21). The first mold part 220 is made of a material such as glass as in the case of known mold parts that are used to produce plastic spectacle lenses, and includes a concave molding face 222 for molding the convex object-side face 204 of the spectacle lens 201 as shown in FIG. 12.

(44) Next, as shown in FIG. 13, a support 224 on which the diffraction grating (optical element) 208 is to be placed is arranged at a predetermined position on the concave molding face 222 of the first mold part 220 (S22). According to the spectacle lens production method of this embodiment, the support 224 is made of the same type of thermosetting resin as the thermosetting resin for forming the spectacle lens main body 202.

(45) Accordingly, in this step, a resin material (monomer) that is a resin for forming the spectacle lens main body 202 is arranged substantially in the shape of cuboid with a flat top portion on a molding face 222 of the first mold part 220, so that the support 224 is formed.

(46) Next, as shown in FIG. 14, the diffraction grating 208 that is an optical element is placed on the top portion of the support 224 (S23). As a result, the diffraction grating 208 is held in a state of being separate from the molding face 222 of the first mold part 220. According to the spectacle lens production method of this embodiment, the diffraction grating 208 is placed on the support 224 in a state in which the resin for forming the support 224 has not been cured.

(47) Next, the resin for forming the support 224 is cured (S24). The resin is cured by being left at room temperature, or through heating or the like.

(48) Moreover, as shown in FIG. 15, the first mold part 220 in which the support 224 with the diffraction grating 208 placed thereon is arranged on the molding face 222 is combined with other mold parts 226, 228, and the like, so that a mold 230 is assembled, and a cavity 232 inside the mold 230 is closed (S25). The diffraction grating 208 placed on the top portion of the support 224 on the molding face 222 of the first mold part 220 is located at a position separate also from a molding face 234 of the mold part 226 and the like.

(49) Next, as shown in FIG. 16, the cavity 232 is filled with a resin material (raw material monomer) M that is a resin for forming the spectacle lens main body 202 (S26). The diffraction grating 208 is separate from the inner faces of the cavity 232 such as the molding face 222 of the first mold part 220 and the molding face 234 of the mold part 226 inside the cavity 232, and thus the diffraction grating 208 is surrounded by the filled resin material M, that is, is not exposed to the outside from the resin material M.

(50) Moreover, the resin material M introduced into the cavity 232 and forming the spectacle lens main body 202 is cured in the cavity 232 through heating to a predetermined temperature (S27). As a result, a spectacle lens in which the diffraction grating 208 that is an optical element is surrounded by a resin in the spectacle lens main body 202 is formed inside the cavity 232.

(51) Lastly, the mold 230 is disassembled, and the spectacle lens 201 molded inside the cavity 232 is detached, that is, released from the mold 230 (S28).

(52) The present disclosure is not limited to the foregoing embodiments, and various changes and modifications are possible within the technical scope of the claims.

(53) In the foregoing embodiment, thermosetting resins were used as the resins, but a configuration may also be employed in which thermoplastic resins are used.

(54) In the foregoing embodiment, a spectacle lens production method was described in which a diffraction grating was used as an optical element that is embedded, but the present disclosure can also be applied to spectacle lens production methods in which other optical elements are embedded.

(55) For example, the present disclosure can also be applied to a method for producing a spectacle lens as shown in FIG. 17 in which a small beads 344 made of a resin with a refractive index different from that of the resin for forming a base portion 342, that is, the main body of a spectacle lens 340 are embedded in the base portion 342 (i.e., arranged without being exposed to the outside). In this spectacle lens, the base portion has a refractive power that corrects short-sightedness, and the small beads have a refractive power higher than that of the base portion. Since the small beads have a refractive power higher than that of the base portion, the focus can be shifted to suppress the progress of refractive errors such as short-sightedness of a person who is wearing the glasses.

(56) When producing the spectacle lens 340 with this configuration, as shown in FIG. 18, a support 346 with a predetermined size and shape made of the same resin material as the thermosetting resin for forming the main body (base portion) 342 of the spectacle lens is arranged at a predetermined position on a molding face 322 of a first mold part 320.

(57) Next, a resin material M2 that is a thermosetting resin with a refractive index different from that of the thermosetting resin for forming the base portion 342 of the spectacle lens is dropped using a dispenser or the like at a plurality of predetermined positions on the support 346. The resin material M2 has a hemispherical shape due to surface tension, and is cured to form small beads 344.

(58) Moreover, after the resin material M2 is cured, as shown in FIG. 19, in a similar way to those of the production methods according to the foregoing embodiments, the first mold part 320 is combined with other mold parts 326, 328, and the like, so that a mold 330 is assembled, and a cavity 332 inside the mold 330 is closed.

(59) Moreover, in a way similar to that of S26 in the foregoing embodiment, the cavity 332 is filled with a resin material that is a thermosetting resin for forming the base portion 342 of the spectacle lens, so that a spectacle lens 340 is obtained in which the small beads 344 are embedded, that is, are arranged inside the base portion 242 without being exposed to the outside.

(60) It is preferable that the hemispherical small beads 344 are set to each have a diameter r of approximately 0.8 to 2.0 mm and a thickness of approximately 0.1 to 1.15 mm. Furthermore, it is preferable that the intervals between adjacent small beads 344 are each set to be approximately equal to the radius (r/2) of the small beads 244. Moreover, it is preferable that the refractive index of the small beads 244 is larger than the refractive power of the base portion 42 by 2.00 to 5.00 diopters.

(61) The base portion 342 of the spectacle lens 340 is made of, for example, a thiourethane-based resin (thermosetting resin) with a refractive index of approximately 1.590 or 1.578, and the small beads 344 are made of, for example, a thiourethane-based resin (thermosetting resin) with a refractive index of approximately 1.5955 and having excellent adhesion to the resin for forming the base portion 342 of the spectacle lens 340. The resin for forming the base portion 342 of the spectacle lens 340 and the resin for forming the small beads 344 may also be other types of thermosetting resins or thermoplastic resins selected as appropriate in consideration of refractive indices.

(62) Furthermore, it is known that a spectacle lens as shown in FIG. 17 in which a plurality of small beads 344 made of a resin with a refractive index different from that of the resin for forming the base portion 342 of the spectacle lens are embedded can shift the focus, thereby suppressing the progress of refractive errors such as short-sightedness of a person who is wearing the glasses.

(63) FIG. 20 is a view illustrating light that passes through the spectacle lens 340 and is incident on an eyeball, specifically, trajectories of light that passes through the base portion 342 and trajectories of light that passes through the small beads 344.

(64) As shown in FIG. 20, light that passes through the base portion 342 of the spectacle lens 340 having a refractive power that corrects short-sightedness is focused on a position f on the retina R, and light that passes through the small beads 344 having a refractive power larger than that of the base portion 342 is focused on positions f′ that are in front of the retina R. That is to say, light that passes through the spectacle lens 340 forms an image on the retina R, and light that passes through the plurality of small beads 344 forms a plurality of images in front of (on the lens side of) the retina R. As a result, while a person who is wearing the glasses using the spectacle lens 340 is viewing an image of an object, the progress of his or her short-sightedness is suppressed.

(65) In the foregoing embodiments, thermosetting resins were used as the resins, but a configuration may also be employed in which thermoplastic resins are used.

LIST OF REFERENCE NUMERALS

(66) 1 Spectacle lens

(67) 2 Spectacle lens main body (base portion)

(68) 4 Object-side face of spectacle lens main body (base portion)

(69) 6 Eyeball-side face of spectacle lens main body (base portion)

(70) 8 Hard coat layer

(71) 10 Anti-reflection coating (AR coating)

(72) 12 Small bead

(73) 12a Flat portion of small bead

(74) 20 First mold part

(75) 22 Molding face of first mold part

(76) 24 Another mold part

(77) 26 Mold

(78) 28 Cavity

(79) M1 Raw material monomer (resin material) for forming spectacle lens main body

(80) M2 Raw material monomer (resin material) for forming small bead

(81) 201 Spectacle lens

(82) 202 Spectacle lens main body

(83) 204 Object-side face of spectacle lens main body

(84) 206 Eyeball-side face of spectacle lens main body

(85) 208 Optical element

(86) 220 First mold part

(87) 222 Molding face of first mold part

(88) 224 Support

(89) 226 Another mold part

(90) 230 Mold

(91) 232 Cavity