KR100510988B1 - Ophthalmic lens with multi-layer forming photo-selective color and low reflection by using optical absorption material and method for controlling the low reflection and the transmitted color - Google Patents

Abstract

The present invention relates to a low reflection multilayer thin film spectacle lens for forming a selective color using a light absorbing material, and a method for manufacturing the same. In the present invention, in the photoselective multilayer thin-film spectacle lens, the convex surface alternately deposits the low refractive index dielectric thin films 3a, 5a, and 7a and the high refractive index dielectric thin films 4a and 6a to have a wavelength having low reflectance in the visible light band. The light absorbing material 9 and the low refractive index dielectric thin films 3b and 5b are alternately deposited on the concave surface to form a transmissive color while reducing the reflectivity of the concave surface, wherein the light absorbing material is nickel (Ni). ); Chromium (Cr); Silver (Ag); There is provided a low reflection multilayer thin film spectacle lens for forming a selective color, which is a metal selected from the group consisting of iron (Fe) and mixtures thereof, or a mixture of said metal and dielectric. The spectacle lens according to the present invention has excellent transmission color formation and low reflection characteristics on the side of the wearer, so that color control and clear field of view can be secured, and eye fatigue can be used as a spectacle lens for various uses.

Description

FIELD OF METHOD FOR CONTROLLING THE LOW REFLECTION AND THE TRANSMITTED COLOR}

The present invention relates to a low reflection multilayer thin film spectacle lens that uses a light absorbing material to form a selective color, and a method of manufacturing the same. Particularly, the convex surface of the spectacle lens controls the deposition thickness and order of the dielectric thin film to adjust the thickness of the visible light band. It is a selective transmission light color low reflection multilayer thin film spectacle lens which provides a low reflection effect directed to antireflection, and simultaneously forms a transmissive color and a low reflection effect by using a light absorbing material and a dielectric in a concave surface. Depending on the purpose of use it can be used for functional glasses for night driver, work or leisure.

Conventional multi-layered thin film technologies of spectacle lenses are sequentially coated with a material having a unique refractive index on a substrate made of glass or plastic, such as low reflection, high reflection, or band-pass filter. It was to give a function of.

In the case of glass, as shown in FIG. 1, the average reflectance is generally about 4%. The low refractive index material SiO ₂ and the high refractive index material ZrO ₂ are repeatedly deposited 22 times in order to deposit 100% of the light in the wavelength range of 460 to 580 nm. This type of deposition is called a high reflection coating. On the contrary, a low reflection coating is used to reduce the reflectance to the maximum and to increase the transmittance by reducing the reflectance.

The result of the low reflection coating is shown in FIG. 2, and the low reflection coating is also manufactured by alternately depositing two materials, SiO ₂ and ZrO ₂ , and adjusts the deposition thickness of the dielectrics and adjusts the order according to the purpose of use. . As a result, depositing dielectrics on glass having a reflectance of 4% or more can lower the reflectance to 2% or less, and at the same time, the average reflection is lowered, thereby improving the transmission. In general, the spectacle lenses have a lower reflectance due to the low reflection multilayer deposition, thereby securing a better transmittance than the lens before deposition.

However, as the low-reflection design for maximizing the light transmission to the spectacle lens as described above, the selection of colors is extremely limited, so that the individual's personality tendency can not be satisfied. In addition, if the transmittance is increased, the clarity is good, but it is not free from external exposure and the eye protection function is insufficient.

On the other hand, Figure 3 shows the process of color formation using coloring, the light passing through the glasses is less transmittance is transmitted to the color of the pigment added to the glasses, not natural light. The color forming method by the coloring is a method of penetrating the dye directly into the surface of the spectacle lens is a manual operation through dipping (General).

Due to this, there is a disadvantage that the reflection characteristics or transmission color of the products are not constant, and the work efficiency is also reduced. In particular, the absorbents introduced into the lens due to the characteristics of the coloring dyes change their physical properties as they are exposed to light for a long time. This results in a problem of discoloration and change in transmission reflection, thereby degrading the adhesion between the coating film interface to inhibit the durability between each coating thin film.

Accordingly, the present applicant is a method for solving the problem of a method of forming a color using an existing absorbent. In Korean Patent Laid-Open Publication No. 2001-0073886, the applicant has almost no absorbent and forms a "selective color using only the wavelength characteristics of a dielectric. Method for controlling a multilayer thin-film spectacle lens and color ", but the invention has a disadvantage in that the anti-reflective control of the wearer side is not easy because the selective color is formed using only the wavelength characteristics of the dielectric.

In addition, the conventional metal film deposition method that forms a metal film and uses a low refractive index dielectric as a protective layer thereon has excellent characteristics of the transmission color, but the reflection of the wearer's wear surface (front and rear surfaces of the lens) is increased and thus the wearer's side surface is increased. Create reflections and virtual images

There are drawbacks to many obstacles.

Thus, the present inventors have used a light absorbing material suitable for the concave surface of the spectacle lens to improve the color formation and anti-reflection control of the wearer side at the same time, and the front and rear reflection of the lens is increased when only the light absorbing material is used. To compensate, the dielectric was deposited to assist in controlling the front and back reflections.

Therefore, in the present invention, unlike the spectacle lens which forms a color using only the dye characteristics of the dye or the dielectric in the conventional color lens, the dielectric of high refractive index and low refractive index is alternately deposited on the convex surface under high vacuum. Multilayer thin film is formed, and concave surface is alternately deposited with light absorbing material and dielectric to satisfy desired transmission color and low reflection effect at the same time. It is an object of the present invention to provide a low-reflection multilayer thin-film spectacle lens that forms a selectable color suitable for a night driver, work, leisure, and the like.

Further, in the present invention, in order to obtain an arbitrary color of the visible light band, a low reflection band composed of five dielectric thin film layers is formed on the convex surface of the spectacle lens coated with a hard film, and particularly, the dielectric thin film layer-light absorbing material thin film layer on the concave surface. -Deposition of three layers of dielectric thin film layer gives the low reflection band and absorbing effect of absorbing material on the side of the wearer to adjust the type and arrangement of dielectric and the thickness of thin film layer so that the desired reflection color, transmission color and low reflection The purpose is to provide a method that can be controlled at the same time.

In order to achieve the above object, in the present invention,

A multi-layered thin film of low refractive index and high refractive index dielectric is formed on the plastic spectacle lens coated with a hard film, and the reflective color is increased on the convex surface of the spectacle lens by increasing the reflectance with respect to a wavelength that can obtain a desired color in the visible wavelength band. In the concave surface, the multi-layer thin-film spectacle lens for increasing the transmittance of the wavelength of the remaining band to form a transmission color of the wavelengths compensating the reflection color, wherein the convex surface has a low refractive index dielectric film (3a, 5a and 7a and the high refractive index dielectric films 4a and 6a are alternately deposited to form wavelength characteristics having low reflectance in the visible light band, and the light absorbing material 9 and the low refractive index dielectric thin films 3b, 5b) are alternately deposited to form a transmissive color while lowering the reflectance of the concave surface, wherein the light absorbing material is nickel (Ni); Chromium (Cr); Silver (Ag); There is provided a low reflection multilayer thin film spectacle lens for forming a selective color, which is a metal selected from the group consisting of iron (Fe) and mixtures thereof or a mixture of this metal and a dielectric.

In the present invention,

A multilayer thin film of a low refractive index dielectric material and a high refractive index dielectric material is formed on a plastic spectacle lens coated with a hard film, and the reflection color is increased on the convex surface of the spectacle lens by increasing the reflectance with respect to a wavelength at which a desired color can be obtained at a wavelength in the visible light band. The method of manufacturing a multilayer thin-film spectacle lens, wherein the concave surface increases the transmittance with respect to the wavelengths of the remaining bands to form a transmission color of wavelengths compensating for the reflection color. The convex surface has a low refractive index dielectric thin film. (3a, 5a, 7a) and the high refractive index dielectric thin films 4a, 6a are alternately deposited to form wavelength characteristics having low reflectance in the visible light band, and the light absorbing material 9 and the low refractive index dielectric thin film are formed in the concave surface. By alternately depositing (3b, 5b) to form a transmission color while reducing the reflectance of the concave surface, wherein the light absorbing material is nickel (Ni); Chromium (Cr); Silver (Ag); Provided is a method for producing a low reflection multilayer thin-film spectacle lens for forming a selective color, which is a metal selected from the group consisting of iron (Fe) and mixtures thereof, or a mixture of this metal and a dielectric.

Hereinafter, with reference to the accompanying drawings with respect to the principle of the reflection color and transmission color of the multilayer thin-film spectacle lens according to the present invention will be described.

In the glass or plastic used as the substrate, the reflectance of the visible light band from 400 to 700 nm is almost the same, so that when a specific color is not observed, the reflection spectrum is observed differently depending on the wavelength band. The color of is stimulated by our eyes with the reflection intensity as the reflection coefficient at that wavelength, and the color is observed. For example, in the case of the low reflection multilayer thin film of FIG. 2, since the relative reflection value at 520 nm is higher than that at the other wavelengths, the viewer's eye is observed in green color.

On the other hand, when only the light absorbing material (for example, metal) is used, it can be seen that the reflectance of the front and rear of the lens is greatly increased as shown in FIG. Therefore, most of these materials have been used for high reflection mirrors (Mirror), half mirror (Half Mirror) and the like. The transmittance and reflectance characteristics of this deposition are shown in FIG. 5.

However, in the present invention, as shown in Figure 6 by forming a thin film of a light-absorbing material on the concave surface of the back of the spectacle lens by the high vacuum deposition technique to obtain the absorption effect of the corresponding light of a specific wavelength and at the same time low refractive index, which is a low reflection layer By alternately depositing dielectrics and interacting with each other, the reflection of the front and rear surfaces of the lens can be suppressed to the maximum, thereby reducing the wearer's field of view. FIG. 7 shows controlled reflectance characteristics at the front surface of the lens after deposition according to the principles of the present invention. When the material absorbing a band of about 600 nm is deposited on the lens, the incident light is transmitted even if the wavelength of the entire spectrum of visible light is transmitted. In the case of tones in the 600nm band are maintained, and if the transmittance is properly adjusted, the effect of realizing the transmission color and the low reflection effect is obtained.

In addition, when the light-absorbing material is deposited between the dielectric thin film as in the present invention, it minimizes the problems such as adhesion between the thin films deposited in multiple layers using only the dielectric and doubles the durability and becomes a thin film under high vacuum. By minimizing the change in physical properties over time by growing, it is possible to compensate for the disadvantages of conventional colored lenses and lenses using only dielectrics.

Table 1 summarizes the method for controlling color and low reflection using a light absorbing material and a dielectric in combination with the conventional technology.

        Comparison of Characteristics According to Collar Forming Method          Method characteristics Method through coloring Selective Color Control Using Dielectrics Color control using a combination of light absorbing material and dielectric Color Discoloration with Time Changes Severe discoloration No discoloration No discoloration Reflective properties Low reflection coating required No need for low reflection coating High reflection No low reflection coating required Low reflection (<3%) Transmission color characteristics Reproducibility and Uniformity Degradation High reproducibility High repeatability and uniformity Adhesion Between Thin Films Degradation of adhesion between hard film and dielectric thin film Same as general dielectric deposition products Improved adhesion of metallic materials Improved adhesion

Hereinafter, a method of manufacturing a low reflection multilayer thin film spectacle lens using a light absorbing material to form a selective color will be described in detail.

Hard membrane coating

The substrate used in the present invention is a plastic lens 1 and is a medium or high refractive lens having a refractive index of 1.5 to 1.7.

Using the lens, hard coating is performed on both the convex and concave surfaces of the lens by dip coating to harden the film. As a coating material, a silica-based hard film having a refractive index in the range of 1.55 to 1.62 is coated with a thickness of 2 to 3 μm depending on the type of substrate used.

Dielectric Thin Film Deposition

After placing the substrate in the chamber, vacuum decompression to 3.0 × 10 ^-5 Torr using a vacuum pump, and then cleaning with atomic units by lens etching using argon gas to maximize the adhesion of the thin film, A uniform dielectric thin film in molecular units is deposited on a substrate by colliding with a target, which is a dielectric, in an electron beam method using hot electrons of a filament applied with high pressure.

8 and 9 show that dielectrics are formed on the front and rear surfaces of the substrate, wherein + is the front surface of the convex portion and − is the back surface of the concave portion. After the thin film layer 3a of the dielectric SiO ₂ is deposited on the hard thin film 2a in consideration of light reflection, the thin film layer 4a of the dielectric ZrO _{2 and} the thin film layer 5a of the dielectric SiO ₂ have a large reflection intensity at a selected wavelength. To this end, the amount of gas is controlled on the surface on which the thin film layer 3 of the dielectric SiO ₂ is deposited, and is deposited together with an ion beam ionized with oxygen to form a columnar structure and increase the uniformity and durability of the thin film.

In particular, in order to impart the antistatic effect and conductivity of the lens to the ball neck of the spectacle lens according to the present invention by depositing about 70 In of In ₂ O ₃ transparent conductive material (8) can be applied as a spectacle lens for computer use have.

After the thin film is designed such that the thin film layer 6a of the dielectric ZrO _{2 and} the thin film layer 7a of SiO ₂ which are important in forming the reflective color have a desired color, an antistatic layer, for example, a thin film layer of In ₂ O ₃ (8) can be deposited on the surface.

The dielectric SiO ₂ thin film layer 3b is deposited on the concave surface, which is the back surface of the lens for forming the transmissive color, to block the transmission of the short wavelength band on the surface coated with the hard film 2b, and then it is repeatedly repeated thereon for proper transmission. The light-absorbing material 9 is deposited to form a collar, and then again the SiO ₂ thin film layer 5b is deposited thereon to obtain a low reflection effect, and at the same time a low reflection that can protect eyesight with a clear field of view and proper field of view color of the wearer. Design by structure.

In the present invention, a thin film is deposited on the substrate through the above process, and the thin films form a reflective and transmissive pattern. The elements that can control the reflective and transmissive pattern include the selection of a dielectric material, the thickness of the dielectric thin film, the sequence of the dielectric array, The temperature in the vacuum deposition chamber, the dielectric deposition method, the vacuum degree in the chamber, the thickness of the light absorbing material, the oxygen partial pressure, the arrangement of the light absorbing material and the dielectric are important factors.

Among these elements, the choice of dielectric, the thickness of the dielectric thin film and the order of the dielectric arrangement, the selection of materials including absorption, the thickness and arrangement of the light absorbing material, and the like are the main factors controlling the colors and low reflection of the present invention.

In the present invention, SiO ₂ and ZrO ₂ are used as the dielectric material selected as an embodiment, but other dielectrics having similar refractive indices may be used. Dielectrics that can be used include MgF ₂ (n: refractive index n = 1.35), LiF (n = 1.36), NaF (n = 1.34), CeF ₃ (n = 1.59) with similar refractive index instead of SiO ₂ with a refractive index of 1.46. ), CeF ₂ (n = 1.23), Al ₂ O ₃ (n = 1.56) and the like can be used. Also, instead of ZrO ₂ with a refractive index of 2.06, TiO ₂ (n = 2.2), ITO (n = 2.2), Y ₂ O ₃ (n = 1.82), ZnS (n = 2.35), La ₂ O ₃ with similar refractive indices , (n = 1.95) and the like can be used.

In particular, a pure metal (nickel (Ni), chromium (Cr), silver (Ag) iron (Fe), etc.) may be used as the light absorbing material formed by depositing on the concave surface of the lens, but a mixture of a metal and a dielectric (for example, , A mixture of chromium and a low refractive index dielectric).

The order of dielectric arrangement determines the deposition order according to the refractive index of the selected dielectric, and the thickness of the dielectric thin film forms a dielectric thin film with an appropriate thickness according to the thin film design. The order and thickness of the dielectric array can be calculated by the optical admittance of each wavelength band and can be adjusted according to the purpose of thin film fabrication. Usually, the design is based on the length of 1/4 times the reference wavelength and slightly modified.

In addition, the order and thickness of the dielectric array may be changed according to the selected wavelength and may be changed depending on the vacuum degree of the vacuum chamber, the temperature of the vacuum chamber, or the deposition state of the thin film.

Through the above process, the reflection intensity, transmission intensity, and phase of light change in each layer with respect to the incident light intensity as a result of the selected dielectric, arrangement order, and thickness. The light-absorbing material may also be appropriately controlled by the size of the absorption, reflection, and transmittance due to alternating deposition with the dielectric in consideration of absorption coefficient and refractive index.

Hereinafter, the present invention will be described in more detail with reference to the following examples and comparative examples, but the following examples do not limit the scope of the present invention.

Example 1

A silica-based hard film having a refractive index of 1.62 was coated on the convex surface of a high refractive index plastic lens having a refractive index of 1.61 to a thickness of 2 μm by a dip coating method, and then the lens substrate was placed in a vacuum chamber and a vacuum pump was used. Reduce the pressure to 3.0 x 10 ^-5 Torr. Then, the deposition is carried out by accelerating the electron beam. In order to increase the uniformity and the physical properties of the thin film, oxygen is ionized to irradiate the substrate with ionization energy. In this manner, a low refractive index dielectric SiO ₂ of 1.46 and a high refractive index dielectric ZrO ₂ of 2.06 were deposited in the order and thickness shown in the following Table 2 and Table 3 before and after the lens.

Particularly, in the case of the back side of the lens, in order to give the transmission color and the low reflection property, the light absorbing material composed of a 1: 4 mixture of chromium (Cr) and SiO ₂ having the optical properties shown in Table 4 below is interposed. SiO ₂ , a low refractive index dielectric material, was deposited in the order and thickness shown in Table 3.

Thin film composition of lens convex surface (+) Material SiO ₂ ZrO ₂ SiO ₂ In ₂ O ₃ ZrO ₂ SiO ₂ Thickness 0.038 λ。 0.065λ. 0.045λ。 0.0137λ. 0.107λ。 0.145λ。

Thin film construction of concave surface (-) of lens Material SiO ₂ Light absorbing material (chromium and SiO ₂ mixture) SiO ₂ Thickeness 0.0308λ ₁ 0.062λ ₁ 0.135λ ₁

Optical properties of light absorbing material (1: 4 mixture of chromium (Cr) and SiO ₂ (w / w)) Wavelength Refractive Index Absorption Coefficient 370 2 0.316 430 2.01 0.3152 450 2.03 0.315 470 2.06 0.314 510 2.07 0.313 550 2.1 0.312 600 2.18 0.31 650 2.3 0.307 675 2.35 0.305 700 2.4 0.3 750 2.4 0.16 780 2.5 0.14 800 2.6 0.12

After the deposition of the dielectric multilayer thin film by the above method, the measured change in the reflection spectrum is shown in FIG. 7, and the wearer feels brown color due to the low reflection band due to the low reflection band of the lens on which the low reflection occurs. The front and rear reflectance of the lens averaged 2.0% and 3.5%.

Comparative Example 1

Comparison of Transmittance between Colored Spectacle Lens and Multi-layer Thin Film Spectacle Lens According to the Present Invention

As a result of comparing and measuring the transmittances of the brown colored multilayer thin film spectacle lens manufactured in Example 1 and the conventional colored spectacle lens and only the general metals, 80% of the spectacle lenses according to the present invention were measured. On the other hand, the colored lens and the metal-deposited lens exhibited transmittances of 60 to 65%, which showed more improved transmittance in the multilayer thin film spectacle lens of the present invention.

Therefore, the multilayer thin-film spectacle lens of the present invention can be used both indoors and outdoors, and can reduce fatigue during computer work or outdoors with strong sunlight.

As can be seen from the results of the above examples and comparative examples, unlike the colored lens is difficult to selectively control the wavelength due to the significant decrease in the transmission of visible light region, the multilayer thin film spectacle lens of the present invention is suitable for light absorbing material and dielectric By array deposition, the transmittance of the color lens can be properly matched to protect the wearer's field of view and to reduce the reflectance as much as possible to ensure a clear field of view.

In addition, the present invention implements a transmission color by an absorbing layer composed of a separate thin film as compared to a conventional colored lens to compensate for the loss of transmittance due to absorption, and changes in color, transmittance, and reflectance when exposed to natural light. Rarely occurs.

Therefore, in the present invention, by using the characteristics as described above, it is possible to freely adjust the transmission pattern of the visible light region can be used for various purposes such as night driver, leisure and computer work, and the reflection and transmission ratio of short wavelength band such as ultraviolet ray When set appropriately, it is possible to secure much higher low reflection and high permeability characteristics than sunglasses using colored dyes or lenses using metallic lenses.

1 is a comparison of the reflectance of the conventional glass and the conventional high reflection coating glass,

2 is a comparison of the reflectance between the conventional glass and the conventional low reflection coating glass,

3 is a color lens for forming a color through a conventional coloring method,

4 is a transmission reflection characteristic when deposited using a conventional metal,

5 is a transmittance and reflectance characteristics of the deposition using a conventional metal,

6 is a transmission reflection characteristic according to the principle of the present invention,

7 is a reflectance characteristic of the front back of the lens after deposition in accordance with the principles of the invention,

8 and 9 are a multi-layer thin film structure of the spectacle lens according to the present invention.

<Description of the symbols for the main parts of the drawings>

1: plastic lens 2a, 2b: hard thin film

3a, 3b, 4a, 5a, 5b, 6a, 7a: dielectric thin film layer 8: transparent conductive thin film layer

9: light absorbing material

Claims (3)

A multi-layered thin film of low refractive index and high refractive index dielectric is formed on the plastic spectacle lens coated with a hard film, and the reflective color is increased on the convex surface of the spectacle lens by increasing the reflectance with respect to a wavelength that can obtain a desired color in the visible wavelength band. In the concave surface, the multi-layer thin-film spectacle lens for forming a transmission color of the wavelengths compensating the reflection color by increasing the transmittance of the wavelength of the remaining band, Low convex dielectric thin films 3a, 5a, and 7a and high refractive index dielectric films 4a and 6a are alternately deposited on the convex surface to form wavelength characteristics having low reflectance in the visible light band, and a light absorbing material on the concave surface. (9) and the low-refractive index dielectric thin films 3b and 5b are alternately deposited to form a transmissive color while lowering the reflectance of the concave surface, wherein the light absorbing material is nickel (Ni); Chromium (Cr); Silver (Ag); A low reflection multilayer thin-film spectacle lens for forming a selective color, characterized in that the metal selected from the group consisting of iron (Fe) and mixtures thereof, or a mixture of this metal and a dielectric material. The method of claim 1, A low reflection multilayer thin film spectacle lens for forming a selective color, characterized in that to provide an antistatic function by forming a transparent conductive thin film layer (8) on the low refractive index dielectric thin film layer (5a). A multi-layered thin film of low refractive index and high refractive index dielectric is formed on the plastic spectacle lens coated with a hard film, and the reflective color is increased on the convex surface of the spectacle lens by increasing the reflectance with respect to a wavelength that can obtain a desired color in the visible wavelength band. In the manufacturing method of the multi-layer thin-film spectacle lens formed in the concave surface to increase the transmittance of the wavelength of the remaining band to form a transmission color of the wavelengths compensating the reflection color, Low convex dielectric thin films 3a, 5a, and 7a and high refractive index dielectric films 4a and 6a are alternately deposited on the convex surface to form wavelength characteristics having low reflectance in the visible light band, and a light absorbing material on the concave surface. (9) and the low-refractive index dielectric thin films 3b and 5b are alternately deposited to form a transmissive color while lowering the reflectance of the concave surface, wherein the light absorbing material is nickel (Ni); Chromium (Cr); Silver (Ag); A method for producing a low reflection multilayer thin film spectacle lens for forming a selective color, characterized in that the metal selected from the group consisting of iron (Fe) and mixtures thereof, or a mixture of this metal and a dielectric material.