JP2005215038A - Spectacle lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spectacle lens for reducing the amount entering the inside of eyeball, by transmitting the spectacle lens by a near-ultraviolet from forward, by allowing the near-ultraviolet rays from oblique rearward, when wearing the spectacle to be reflected on a face of an eyeball side of the spectacle lens to reduce an amount entering the inside of the eyeball. <P>SOLUTION: In a coat formed on the face of the eyeball side of the spectacle lens, comprising a transparent base substance and the surface of an outside face, on the spectacle lens a coat which reflects or absorbs wavelength range near-ultraviolet of 350 nm-400 nm on the outside face of the spectacle lens, and forms an antireflection film transmitting the near-ultraviolet on the face of the eyeball side of the spectacle lens. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a spectacle lens provided with an antireflection film.

  In recent years, plastic lenses are more widely used than glass lenses. The use of plastic as the base material has the advantage of being lighter and easier to process than glass, but also has the disadvantage of being easily scratched and having a low refractive index and a thick lens. Therefore, in order to make it hard to be damaged, a technique for forming a cured film on the surface of a plastic substrate to make it difficult to be damaged is becoming common. As a result of increasing the refractive angle of light by improving the refractive index of the substrate, the lens can be made thinner. In addition, a cured film formed on the base material has a refractive index close to that of the lens base material in order to make interference fringes difficult to see.

  On the other hand, increasing the refractive index of the base material and the cured film inevitably increases the reflectance of light on the lens surface, so there is a technology to reduce the reflectance in the visible light region by forming an antireflection film. Widely introduced. Equipped with an anti-reflective coating to suppress the reflection of light on the surface, increase the amount of transmitted light, and reduce the reflection of images from behind (ghost phenomenon) to make the field of view through the lens clear. I can do it.

  In addition, since the recognition of the adverse effect of ultraviolet rays on the eyeball is also increasing, a device has been devised that can cut ultraviolet rays in spectacle lenses. By adding an ultraviolet absorber to the plastic substrate or hard coat layer, the amount of ultraviolet rays that pass through the spectacle lens can be greatly reduced.

JP-A-6-88064 Japanese Patent No. 172742 Japanese Patent Laid-Open No. 9-265059 JP 2001-91906 A Japanese Patent Publication No. 6-85002 Japanese Patent Publication No.7-119844

  In the case of an antireflection film having about 4 to 7 layers, which is usually provided in spectacle lenses, the antireflection band is only in the visible light region. Therefore, the reflectance of near ultraviolet rays and near infrared rays in the wavelength range of 350 nm to 400 nm has been increased. FIG. 1 shows the positional relationship between the eyeball and the lens when the spectacle lens is worn, the direction in which light enters and the name of the lens surface. Regarding the light 1 coming from the front, it can be said that the increase in the reflectivity of near ultraviolet rays and near infrared rays is good from the viewpoint of preventing the invasion into the eyeball, but the light 2 coming from the oblique rear is near ultraviolet rays as reflected light to the eyeball. Or near infrared rays will invade the eyes. Since near ultraviolet rays may adversely affect the eyeball tissue, we want to reduce the amount that enters the eyeball as much as possible. However, in the case of plastic spectacle lenses, near ultraviolet rays coming from the front as described above prevent reflection in the visible light range. The amount that reaches the eyeball can be reduced by the high near-UV reflectivity by the film, the absorption of the plastic substrate itself, and the added UV absorber. However, the near-ultraviolet rays from diagonally behind the anti-reflection film on the eyeball side of the spectacle lens become an anti-reflection film with a high reflectivity of near-ultraviolet rays, and a considerable amount of near-ultraviolet light enters the eyeball. It was.

  The present invention reduces the amount of near-ultraviolet rays from obliquely behind when spectacles are worn being reflected by the eyeball-side surface of the spectacle lens and entering the eyeball, and the near-ultraviolet rays from the front pass through the spectacle lens and the eyeball The object is to provide a spectacle lens with a reduced amount.

  Near-ultraviolet rays from obliquely behind may be reflected on both surfaces of the spectacle lens. However, if it is reflected off the outer surface but not on the eyeball side surface, the amount of near UV rays that are reflected on the outer surface and reach the eyeball due to absorption by the plastic substrate itself or the added UV absorber is Slightly. Therefore, it has been found that when reducing the amount of near-ultraviolet rays entering from the oblique rear side into the eyeball, it is only necessary to consider reducing the reflectance that occurs on the eyeball side surface. Moreover, near ultraviolet rays coming from the front were able to reduce the amount reaching the eyeball by reflecting or absorbing near ultraviolet rays on the outer surface. In order to achieve the above object, the following inventions have been made.

  A first aspect of the present invention is a film formed on the eyeball side surface and the outer surface of a spectacle lens made of a transparent substrate, and the outer surface of the spectacle lens has a wavelength range of 350 nm. The present invention relates to a spectacle lens characterized in that a coating that reflects or absorbs near-ultraviolet rays of 400 nm is formed, and an antireflection film that transmits the near-ultraviolet rays is formed on the eyeball side surface of the spectacle lens. .

  In the second aspect of the invention, the near-ultraviolet ray reflectance in the wavelength range of 350 nm to 400 nm is set to 0.1% to 1% on the eyeball side surface of the spectacle lens, and the visible light reflectance in the wavelength range of 400 nm to 650 nm is set. The present invention relates to a spectacle lens comprising an antireflection film having an antireflection property suppressed to 0.3% or more and 1.5% or less.

  According to the first and second inventions, the harmful near ultraviolet rays are reflected or absorbed in the light from the front, and the harmful near ultraviolet rays are transmitted forward in the obliquely backward light. It is possible to reduce the penetration of near ultraviolet rays.

According to a third invention, in the spectacle lenses of the first and second inventions, SiO ₂ is used for the low refractive index layer on the eyeball side surface of the spectacle lens, and TiO ₂ and Nb ₂ O ₅ are used for the high refractive index layer. Either or both of these are used, and an antireflection film comprising at least three low refractive index layers and high refractive index layers alternately stacked is provided.

  According to the third aspect of the present invention, it is possible to obtain the desired antireflection characteristic while reducing the number of antireflection films as much as possible, and the durability quality required for glasses can be obtained.

  The fourth invention is characterized in that in the spectacle lens of the first to third inventions, a film that absorbs near ultraviolet rays having a wavelength range of 350 nm to 400 nm is formed on the outer surface of the spectacle lens.

  According to the fourth invention, it is possible to reduce the amount of near ultraviolet rays that pass through the spectacle lens and reach the eyeball by selectively absorbing near ultraviolet rays in the coating.

  According to a fifth aspect of the present invention, in the spectacle lens of the first to third aspects of the invention, the outer surface of the spectacle lens absorbs near ultraviolet rays having a wavelength range of 350 nm to 400 nm and 5% of near ultraviolet rays having a wavelength range of 350 nm to 400 nm. An antireflection film reflecting the above is formed.

  According to the fifth invention, the outer surface of the spectacle lens has not only a coating that absorbs near-ultraviolet rays but also a coating that reflects, thereby further preventing near-ultraviolet rays from entering the eyeball from the front. is there.

  According to a sixth invention, in the spectacle lenses of the first to third and fifth inventions, a layer containing metal oxide fine particles is formed on a spectacle lens substrate, and an antireflection film is formed thereon. It is characterized by doing.

  According to the sixth aspect of the invention, it is possible to improve the adhesion between the spectacle lens substrate and the antireflection film and realize a spectacle lens with a highly durable antireflection film.

  Near-ultraviolet rays coming from diagonally behind when wearing spectacle lenses by making the antireflection film formed on the eyeball side surface of the spectacle lens have a reflectance in the range of 350 nm to 400 nm of 0.1% to 1%. However, I was able to greatly reduce entering the eyeball. By forming a film that absorbs or reflects near ultraviolet rays on the outer surface of the spectacle lens, it was possible to block near ultraviolet rays coming from the front with a high probability. At the same time, it was possible to provide a spectacle lens that is required to be used as spectacles and that also prevents the reflection of visible light.

[Example 1]
FIG. 2- (1) shows a plastic spectacle lens model. FIG. 2- (2) shows a model of the film formed on the eyeball side surface of the plastic spectacle lens. FIG. 2- (3) shows a model of the film formed on the outer surface of the plastic spectacle lens. 2 (1), (2), and (3) are exaggerated for convenience of explanation.

An antireflection film consisting of 7 layers was formed on the eyeball side surface. Its design principal wavelength λ0 is 470 nm, and each layer is counted from the plastic spectacle lens substrate side,
In the first layer 21, an SiO ₂ layer (refractive index 1.46) having an optical film thickness of 0.090λ0,
In the second layer 22, a TiO ₂ layer (refractive index 2.40) having an optical film thickness of 0.094λ0,
In the third layer 23, an SiO ₂ layer having an optical film thickness of 0.085λ0,
In the fourth layer 24, a TiO ₂ layer having an optical film thickness of 0.221λ0,
In the fifth layer 25, an SiO ₂ layer having an optical film thickness of 0.051λ0,
In the sixth layer 26, a TiO ₂ layer having an optical film thickness of 0.148λ0,
On the seventh layer 27, an antireflection film was formed by sequentially laminating SiO ₂ layers having an optical film thickness of 0.266λ0. The thickness of the formed antireflection film is about 240 nm to 250 nm.

  On the outer surface of the spectacle lens, a hard coat layer 28 mainly composed of metal oxide fine particles added with an ultraviolet absorber and an organosilicon compound was formed by spin coating. The thickness of the deposited hard coat layer is about 2 μm to 3 μm. Both the refractive index of the plastic spectacle lens substrate and the hard coat layer are 1.67.

  In FIG. 3, the reflectance spectrum of the antireflection film formed on the eyeball side surface is shown by a curve 31. FIG. 4 shows a near-ultraviolet transmittance spectrum of the plastic spectacle lens substrate on which the hard coat layer is formed as a curve 41.

[Comparative Example 1]
FIG. 5- (1) shows a plastic spectacle lens model. FIG. 5- (2) shows a model of a film formed on the eyeball side surface of the plastic spectacle lens. FIG. 5- (3) shows a model of the film formed on the outer surface of the plastic spectacle lens. 5 (1), (2), and (3) are exaggerated for convenience of explanation.

On the eyeball side surface, an antireflection film consisting of 7 layers was formed, which was the same as the material of Example 1 in the order of lamination and differed only in the optical film thickness of each layer. Its design principal wavelength λ0 is 510 nm, and each layer is counted from the plastic spectacle lens substrate side,
In the first layer 51, an SiO ₂ layer (refractive index 1.46) having an optical film thickness of 0.060λ0,
In the second layer 52, a TiO ₂ layer (refractive index 2.40) having an optical film thickness of 0.063λ0,
In the third layer 53, an SiO ₂ layer having an optical film thickness of 0.110λ0,
In the fourth layer 54, a TiO ₂ layer having an optical film thickness of 0.193λ0,
In the fifth layer 55, an SiO ₂ layer having an optical film thickness of 0.060λ0,
In the sixth layer 56, a TiO ₂ layer having an optical film thickness of 0.165λ0,
On the seventh layer 57, an antireflection film was formed by sequentially laminating SiO ₂ layers having an optical film thickness of 0.275λ0. The thickness of the formed antireflection film is about 260 nm to 270 nm.

  On the outside of the spectacle lens, a hard coat layer 58 mainly composed of metal oxide fine particles and an organosilicon compound was formed by spin coating. The thickness of the deposited hard coat layer is about 2 μm to 3 μm. Both the refractive index of the plastic spectacle lens substrate and the hard coat layer are 1.67.

  In FIG. 3, the reflectance spectrum of the antireflection film formed on the eyeball side surface is shown by a curve 32. FIG. 4 shows a near-ultraviolet transmittance spectrum of the plastic spectacle lens substrate on which the hard coat layer is formed as a curve 42.

Example 1 and Comparative Example 1 are compared.
From the results of FIGS. 3 and 4, for near ultraviolet rays coming obliquely from behind, in the curve 31 showing Example 1 and the curve 32 showing Comparative Example 1 in FIG. 3, the curve 31 is more than 400 nm than the curve 32. In the short wavelength range, the reflectance is dramatically reduced. That is, Example 1 can reduce the amount of near-ultraviolet rays that come from obliquely rearward and are reflected from the eyeball side surface and enter the eyeball.

  As for the near ultraviolet rays coming from the front, looking at the curve 41 showing Example 1 and the curve 42 showing Comparative Example 1 in FIG. 4, the curve 41 shows the right side of the curve 42, that is, the transmittance is small. Yes. This indicates that Example 1 was able to increase the absorption efficiency of near ultraviolet rays coming from the front by adding an ultraviolet absorber to the hard coat layer on the outer surface.

  From the above, an antireflection film with a reduced near ultraviolet reflectance is formed on the eyeball side surface, and a hard coat layer to which an ultraviolet absorber is added is formed on the outer surface, thereby entering the eyeball. It was confirmed that the amount of near ultraviolet rays could be reduced.

[Example 2]
FIG. 6- (1) shows a model of a plastic spectacle lens. FIG. 6 (2) shows a model of a film formed on the eyeball side surface of the plastic spectacle lens. FIG. 6- (3) shows a model of a film formed on the outer surface of the plastic spectacle lens. 6 (1), (2), and (3) are exaggerated for convenience of explanation.

  Hard coat layers 601 and 602 mainly composed of metal oxide fine particles added with an ultraviolet absorber and an organosilicon compound were formed on a plastic spectacle lens substrate by dipping. The hard coat layer is formed on both the eyeball side surface and the outer surface and has a thickness of about 2 μm to 3 μm. The refractive indexes of the plastic spectacle lens substrate and the hard coat layer are both 1.60.

An antireflection film consisting of 9 layers was formed on the eyeball side surface. Its design principal wavelength λ0 is 500 nm, and each layer is counted from the plastic spectacle lens substrate side,
In the first layer 611, an SiO ₂ layer (refractive index 1.46) having an optical film thickness of 0.100λ0,
In the second layer 612, an Nb ₂ O ₅ layer (refractive index: 2.26) having an optical film thickness of 0.068λ0,
In the third layer 613, a SiO ₂ layer having an optical film thickness of 0.085λ0,
In the fourth layer 614, an Nb ₂ O ₅ layer having an optical film thickness of 0.090λ0,
In the fifth layer 615, an SiO ₂ layer having an optical film thickness of 0.013λ0,
In the sixth layer 616, an Nb ₂ O ₅ layer having an optical film thickness of 0.110λ0,
A SiO ₂ layer having an optical film thickness of 0.055λ0 on the seventh layer 617,
In the eighth layer 618, an Nb ₂ O ₅ layer having an optical film thickness of 0.123λ0,
On the ninth layer 619, an antireflection film was formed by sequentially laminating SiO ₂ layers having an optical film thickness of 0.250λ0. The thickness of the formed antireflection film is about 255 nm to 265 nm.

An antireflection film consisting of five layers was formed on the outer surface. Its design principal wavelength λ0 is 520 nm, and each layer is counted from the plastic substrate side.
In the first layer 621, an SiO ₂ layer (refractive index 1.46) having an optical film thickness of 0.088λ0,
On the second layer 622, a ZrO ₂ layer (refractive index of 2.05) having an optical film thickness of 0.160λ0,
In the third layer 623, an SiO ₂ layer having an optical film thickness of 0.050λ0,
In the fourth layer 624, a ZrO ₂ layer having an optical film thickness of 0.270λ0,
On the fifth layer 625, an antireflection film was formed by sequentially laminating SiO ₂ layers having an optical film thickness of 0.265λ0. The thickness of the formed antireflection film is about 240 nm to 250 nm.

  FIG. 7 shows a reflectance spectrum of the antireflection film formed on the eyeball side surface by a curve 71. FIG. 8 shows a reflectance spectrum of an antireflection film formed on the outer surface by a curve 81. FIG. 9 shows a transmittance spectrum of the plastic spectacle lens substrate on which the hard coat layer is formed.

[Comparative Example 2]
FIG. 10- (1) shows a plastic spectacle lens model. FIG. 10- (2) shows a model of the coating film formed on the eyeball side surface of the plastic spectacle lens. FIG. 10- (3) shows a model of a film formed on the outer surface of the plastic spectacle lens. 10- (1), (2), and (3) are exaggerated for convenience of explanation.

  Hard coat layers 1001 and 1002 mainly composed of metal oxide fine particles added with an ultraviolet absorber and an organosilicon compound were formed on a plastic spectacle lens substrate by dipping. The hard coat layer is formed on both the eyeball side surface and the outer surface and has a thickness of about 2 μm to 3 μm. The refractive indexes of the plastic spectacle lens substrate and the hard coat layer are both 1.60.

An antireflection film having the same configuration consisting of seven layers was formed on both the eyeball side surface and the outer surface. Its design principal wavelength λ0 is 520 nm, and each layer is counted from the plastic spectacle lens substrate side,
In the first layers 1011 and 1021, an SiO ₂ layer (refractive index 1.46) having an optical film thickness of 0.063λ0,
In the second layers 1012 and 1022, a Ta ₂ O ₅ layer (refractive index: 2.26) having an optical film thickness of 0.050λ0,
In the third layers 1013 and 1023, an SiO ₂ layer having an optical film thickness of 0.100λ0,
In the fourth layers 1014 and 1024, a Ta ₂ O ₅ layer having an optical film thickness of 0.175λ0,
In the fifth layers 1015 and 1025, an SiO ₂ layer having an optical film thickness of 0.060λ0,
In the sixth layers 1016 and 1026, a Ta ₂ O ₅ layer having an optical film thickness of 0.165λ0,
On the seventh layers 1017 and 1027, an antireflection film was formed by sequentially laminating SiO ₂ layers having an optical thickness of 0.275λ0. The thickness of the formed antireflection film is about 260 nm to 270 nm.

  7 and 8 show the reflectance spectrum of the formed antireflection film as a curve 72 and a curve 82, respectively. FIG. 9 shows a transmittance spectrum of the plastic spectacle lens substrate on which the hard coat layer is formed.

Example 2 and Comparative Example 2 are compared.
As shown in FIG. 9, there is no difference in the near-ultraviolet absorbing ability between the plastic spectacle lens substrate and the hard coat layer. However, as shown in FIGS. 7 and 8, there is a difference in near-ultraviolet reflection characteristics between the eyeball side surface and the outer surface.

  First, the near-ultraviolet reflection characteristics on the eyeball side surface will be described. When the curve 71 indicating the second embodiment in FIG. 7 is compared with the curve 72 indicating the second comparative example, the reflectance of the curve 71 is dramatically reduced in a wavelength region shorter than 400 nm. That is, Example 2 can reduce the amount of near-ultraviolet rays that come from obliquely behind and are reflected by the eyeball side surface and enter the eyeball.

  Next, the near-ultraviolet reflection characteristics on the outer surface will be examined. When the curve 81 showing the second embodiment in FIG. 8 is compared with the curve 82 showing the second comparative example, the curve 81 has a higher near-UV reflectance. That is, Example 2 shows that more near-ultraviolet rays coming from the front could be reflected.

  As described above, an antireflection film having a low near-UV reflectivity is formed on the eyeball side surface, and an antireflection film having a high near-UV reflectivity is formed on the outer surface, thereby entering the eyeball. It was confirmed that the amount of near ultraviolet rays could be reduced.

  In addition to the vision correction function, it is possible to provide a spectacle lens having an eyeball protection function from ultraviolet rays.

The positional relationship between the eyeball and the lens when the spectacle lens is worn, and the direction in which light enters and the name of the lens surface. The model of the film formed into a film on the plastic spectacle lens surface shown in Example 1. FIG. The reflectance spectrum of the antireflection film shown in Example 1 and Comparative Example 1. The near-ultraviolet-ray transmittance spectrum of the plastic spectacle lens base material which formed the hard-coat layer into a film as shown in Example 1 and Comparative Example 1. The model of the film | membrane formed into a film on the plastic spectacle lens surface shown in the comparative example 1. FIG. The model of the film formed into a film on the plastic spectacle lens surface shown in Example 2. FIG. The reflectance spectrum of the anti-reflective film formed in the plastic spectacle lens eyeball side shown in Example 2 and Comparative Example 2. The reflectance spectrum of the anti-reflective film formed into the outer side of the plastic spectacle lens shown in Example 2 and Comparative Example 2. The near-ultraviolet-ray transmittance spectrum of the plastic spectacle lens base material which formed the hard-coat layer into the film shown in Example 2 and Comparative Example 2. The model of the coating film formed on the plastic spectacle lens surface shown in Comparative Example 2.

Explanation of symbols

21, 23, 25, 27 SiO ₂ layer 22, 24, 26 TiO ₂ layer 28 Hard coat layer 31 Reflectivity of antireflection film of Example 1 32 Reflectivity of antireflection film of Comparative Example 1 41 Hard of Example 1 Near-UV transmittance 42 of coated plastic substrate Near-UV transmittance 51, 53, 55, 57 of SiO ₂ layer 52, 54, 56 TiO ₂ layer 601, 602 Hard coat layer of hard coated plastic substrate of Comparative Example 1 611, 613, 615, 617, 619, 621, 623, 625 SiO ₂ layer 612, 614, 616, 618 Nb ₂ O ₅ layer 622, 624 ZrO ₂ layer 71, 81 Reflectivity 72 of the antireflection film of Example 2 , 82 Reflectivity of the antireflection film of Comparative Example 2 1001, 1002 Hard coat layers 1011, 1013, 1015, 1017, 1021, 1023, 10 5,1027 SiO ₂ layer 1012,1014,1016,1022,1024,1026 Ta ₂ O ₅ layer

Claims (6)

  A film formed on a surface of an eyeball side of a spectacle lens made of a transparent base material and a surface of an outer surface which is a surface opposite to the eyeball side surface of the spectacle lens, A film that reflects or absorbs near ultraviolet rays having a wavelength range of 350 nm to 400 nm is formed on the outer surface, and an antireflection film that transmits the near ultraviolet rays is formed on the eyeball side surface of the spectacle lens. Eyeglass lenses characterized by   On the eyeball side surface of the spectacle lens, the reflectance of near ultraviolet rays having a wavelength range of 350 nm to 400 nm is 0.1% or more and 1% or less, and the reflectance of visible light having a wavelength range of 400 nm to 650 nm is 0.3% or more. The spectacle lens according to claim 1, wherein an antireflection film having an antireflection property suppressed to 1.5% or less is formed. The eyeglass side surface of the spectacle lens is made of SiO ₂ for the low refractive index layer and TiO ₂ and / or Nb ₂ O _{5 for} the high refractive index layer, or both. The spectacle lens according to claim 1, wherein an antireflection film is formed by alternately stacking three or more refractive index layers.   The spectacle lens according to any one of claims 1 to 3, wherein a film that absorbs near ultraviolet rays having a wavelength range of 350 nm to 400 nm is formed on the outer surface of the spectacle lens.   A film that absorbs near ultraviolet rays having a wavelength range of 350 nm to 400 nm and an antireflection film that reflects near ultraviolet rays having a wavelength range of 350 nm to 400 nm are formed on the outer surface of the spectacle lens. The spectacle lens according to any one of claims 1 to 3. 4. A layer containing metal oxide fine particles is formed on a base material of the spectacle lens, and an antireflection film is formed on a film containing the metal oxide fine particles. The spectacle lens according to any one of 5.

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