EP2961602A1 - Anti-reflective coating - Google Patents
Anti-reflective coatingInfo
- Publication number
- EP2961602A1 EP2961602A1 EP14756263.1A EP14756263A EP2961602A1 EP 2961602 A1 EP2961602 A1 EP 2961602A1 EP 14756263 A EP14756263 A EP 14756263A EP 2961602 A1 EP2961602 A1 EP 2961602A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- nonmetallic
- layer
- reflective coating
- metal layer
- group
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
- C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
- C23C28/34—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
- C23C28/345—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates with at least one oxide layer
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
- C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
- C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
- C23C28/321—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer with at least one metal alloy layer
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
- C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
- C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
- C23C28/322—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer only coatings of metal elements only
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
- C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
- C23C28/34—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
- G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
- G02B1/11—Anti-reflection coatings
- G02B1/111—Anti-reflection coatings using layers comprising organic materials
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
- G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
- G02B1/11—Anti-reflection coatings
- G02B1/113—Anti-reflection coatings using inorganic layer materials only
- G02B1/115—Multilayers
- G02B1/116—Multilayers including electrically conducting layers
Definitions
- the invention relates to optical coatings, in particular, to anti-reflective optical coatings and can be used to avoid or largely decrease an ambient light reflection from displays and devices for optical communication and information processing.
- a well known anti-reflective coating on a substrate described e.g. in P.W.Bauffle "Optical Coating Technology", pagel-3, fig.1-7 and page 4-11, section 4.3.2, published by SPIE, Washington, USA, 2004 includes one nonmetallic layer having a refractive index less than a substrate refractive index and of quarter-wave optical thickness (the optical thickness of layer is its physical thickness multiplied by the refractive index of the layer).
- This known anti-reflective coating decreases an ambient light residual reflection to 1.5-2% instead of 4-5% of a bare substrate.
- a drawback of this one-layer anti-reflective coating is a relatively high residual reflection.
- Another well known anti-reflective coating on a substrate described e.g. in P.W.Bauffle "Optical Coating Technology", page 4-12, section 4.3.3.1, published by SPIE, Washington, USA, 2004 includes first nonmetallic layer having a refractive index greater than the substrate refractive index and second nonmetallic layer having a refractive index less than the refractive index of the first nonmetallic layer, wherein the first nonmetallic layer is placed between the second nonmetallic layer and a substrate.
- This known anti-reflective coating decreases an ambient light residual reflection to 0.5-1% instead of 4-5% of a bare substrate.
- a drawback of this two-layer anti-reflective coating is a pronounced color of reflected light instead of a needed neutral tint.
- Another well known anti-reflective coating on a substrate described, e.g. in P.W.Baumeister "Optical Coating Technology", page 1-14, section 1.3.1.3, published by SPIE, Washington, USA, 2004 includes a set of alternate layers (not less than four layers) with a high and a low reflective indices.
- This known anti-reflective coating decreases an ambient light residual reflection to 0.1-0.5% instead of 4-5% of a bare substrate.
- a drawback of this multi-layer anti-reflective coating is a relatively high manufacture cost due to many layer deposition as well as adjustment difficulties.
- An object of the invention is an anti-reflective coating supplying on a substrate providing an ambient light residual reflection for visible light as low as 0.1-0.5% at a needed neutral tint.
- Another object of the invention while providing low ambient light residual reflection at a needed neutral tint is to minimize amount of layers (not more than three layers) anti-reflective coating consists of, which therefore ensures low cost.
- these objects for visible light are reached with anti- reflective coating on a substrate including one metal layer of a thickness ranging from 2 to 5 nanometers and one nonmetallic layer having reflective index ranging from 1.3 to 1.6 and a thickness ranging from 40 to 80 nanometers, wherein the metal layer is placed between the nonmetallic layer and the substrate.
- anti-reflective coating on substrate including one metal layer of a thickness ranging from 2 to 12 nanometers, first nonmetallic layer having refractive index not exceeding 1.7 and thickness ranges from 30 to 100 nanometers, second nonmetallic layer having refractive index greater than 1.7 and thickness ranges from 10 to 50 nanometers, with difference between refractive indices of second and first nonmetallic layers not less than 0.3, wherein second nonmetallic layer is placed on substrate, the metal layer is placed on second nonmetallic layer, and first nonmetallic layer is placed on the metal layer.
- Fig.l shows a first embodiment of anti-reflective coating consisting of one nonmetallic layer having refractive index of not greater than 1.6 and one metal layer of a thickness ranging from 2 to 5 nanometers placed between the nonmetallic layer and substrate.
- Fig.2 shows ambient visible light reflection spectrum of anti-reflective coating according to Fig.l.
- Fig.3 shows a second embodiment of anti-reflective coating consisting of the first nonmetallic layer having refractive index of not greater than 1.7 and the second nonmetallic layer having refractive index of greater than 1.7 and one metal layer, wherein the second nonmetallic layer is placed on substrate, the metal layer is placed on second nonmetallic layer, first nonmetallic layer is placed on the metal layer.
- Fig.4 shows ambient visible light reflection spectrum of anti-reflective coating according to Fig.3.
- Fig.l a first embodiment of anti-reflective coating on substrate 3 for visible light including one metal layer 1 of a thickness ranging from 2 to 5 nanometers and one nonmetallic layer 2 having reflective index ranging from 1.3 to 1.6 and a thickness ranging from 40 to 80 nanometers, wherein the metal layer 1 is placed between the nonmetallic layer 2 and a substrate 3 is shown.
- Anti-reflective coating works as follows.
- the ambient white light 4 enters into the anti-reflective coating and is reflected from each interface: "air-nonmetallic layer 2", “nonmetallic layer 2 - metal layer 1", “metal layer 1 - substrate 3".
- a total intensity of reflected light 5 is a very low at certain and properly chosen thickness and refractive index of the nonmetallic layer 1 and optical properties of metal and its thickness.
- Metal layer preferably, is made of the metals chosen from a group comprising: gold Au, silver Ag, aluminum Al, copper Cu, chromium Cr, titanium Ti, nickel Ni, manganese Mn, molybdenum Mo, bismuth Bi, tin Sn, rhodium Rh, platinum Pt, antimony Sb and any alloy or solid solution of mentioned substances.
- the metal layer 1 can include additionally sub-layers that have a thickness of not greater than 1 nanometer and made of materials selected from a group comprising: chromium Cr, titanium Ti, nickel Ni, vanadium V, zirconium Zr, hafnium Hf, niobium Nb, molybdenum Mo, and any mixture, alloy or solid solution of mentioned substances.
- Thickness of metal layer 1 depends on which metal is used as well as on thickness and refractive index of nonmetallic layer 2 and ranges from 2 to 5 nanometers. Metal thickness lower than 2 nanometers has no significant influence on a visible reflection vs nonmetallic layer only. Metal thickness higher than 5 nanometers increases a visible reflection at "blue” and “red” wavelength ranges and, therefore, a total reflection of visible white light; also undesirable pronounced color of reflected light is generated.
- Known methods are used for a deposition of metal layer 1 on substrate 3: thermal evaporation, evaporation by an electronic beam, deposition by pulverization, by an ion beam, by cathode pulverization, by vapor phase chemical deposition assisted by plasma, etc.
- Nonmetallic layer 2 is made of substances selected from group comprising magnesium, calcium, barium, aluminum, lanthanum fluorides MgF 2 , CaF 2 , AIF 3 , LaF 3 , Si0 2 , and any mixture, alloy, or solid solution of mentioned substances. Also organic polymer group comprising of acrylate- and fluoro-polymers are used. Other materials having refractive index not exceeding 1.6 and not mentioned here are possible to use.
- Thickness of nonmetallic layer 2 depends on type of nonmetallic substance, mainly on its refractive index, as well as on thickness and type of metal layer 1 and ranges from 40 to 80 nanometers.
- Known methods are used for a deposition of nonmetallic layer 2: thermal evaporation, evaporation by an electronic beam, by pulverization by an ion beam, by cathode pulverization, by vapor phase chemical deposition assisted by plasma, etc. Also wet coating methods are used.
- Substrate 3 (a display or other device outer surface) is made from a dielectric material, for example, from glass or polymer.
- Fig.2 an ambient visible light reflection spectrum of anti-reflective coating according to Fig.l is depicted. It is clearly seen that a residual reflection of white light does not exceed 0.35% and has an almost neutral tint (due to a uniform reflection within the visible spectrum range).
- a second embodiment of the invention is shown, This anti-reflective coating on substrate 3 for visible light, including one metal layer 1 of a thickness ranging from 2 to 12 nanometers, first nonmetallic layer 2 having refractive index not exceeding 1.7 and thickness ranges from 30 to 100 nanometers, second nonmetallic layer 6 having refractive index greater than 1.7 and thickness ranges from 10 to 50 nanometers, with difference between refractive indices of second and first nonmetallic layers not less than 0.3, wherein second nonmetallic layer 6 is placed on substrate 3, the metal layer 1 is placed on second nonmetallic layer 6, and first nonmetallic layer 2 is placed on the metal layer 1.
- Anti-reflective coating works as follows.
- the ambient white light 4 enters into the anti-reflective coating and is reflected from each interface: "air-nonmetallic layer 2", “nonmetallic layer 2 - metal layer 1", “metal layer 1 - second nonmetallic layer 6", “second nonmetallic layer 6 - substrate 3".
- air-nonmetallic layer 2 enters into the anti-reflective coating and is reflected from each interface: "air-nonmetallic layer 2", “nonmetallic layer 2 - metal layer 1", “metal layer 1 - second nonmetallic layer 6", “second nonmetallic layer 6 - substrate 3".
- the total intensity of reflected light 5 is very low with a proper choice of metal and nonmetallic materials, their thicknesses and refractive indices of nonmetallic layers 2 and 6.
- Metal layer preferably, is made of the materials chosen from group comprising gold Au, silver Ag, aluminum Al, copper Cu, chromium Cr, titanium Ti, nickel Ni, manganese Mn, molybdenum Mo, bismuth Bi, tin Sn, rhodium h, platinum Pt, antimony Sb and any mixtures, alloys, solid solutions or intermetallic compounds of mentioned substances.
- the metal layer 1 can include additionally sub-layers that have a thickness of not greater than 1 nanometer and made of materials selected from group comprising chromium Cr, titanium Ti, nickel Ni, vanadium V, zirconium Zr, hafnium Hf, niobium Nb, molybdenum Mo, and any mixtures, alloys, solid solutions, or intermetallic compounds of mentioned substances.
- Thickness of the metal layer 1 depends on sort of metal and on thicknesses and refractive indices of nonmetallic layers 2 and 6, and ranges from 2 to 12 nanometers. Metal thickness lower than 2 nanometers has no significant influence on a visible reflection vs nonmetallic layers only. Metal thickness higher than 12 nanometers increases a visible reflection at "blue” and “red” wavelength ranges and, therefore, a total reflection of visible white light; also undesirable pronounced color of reflected light is generated.
- Methods used for a deposition of metal layer 1 on nonmetallic layer 6 are known: magnetron sputtering, thermal evaporation, evaporation by an electronic beam, by pulverization, by an ion beam, by cathode pulverization, by (plasma enhanced) chemical vapor deposition, etc.
- Methods used for a deposition of nonmetallic layers 2 and 6 are known: magnetron sputtering, thermal evaporation, electronic beam evaporation, sol-gel, (plasma enhanced) chemical vapor deposition, etc.
- Nonmetallic layer 2 having refractive index not exceeding 1.7 is made of materials selected from group comprising magnesium, calcium, barium, aluminum, lanthanum fluorides MgF 2 , CaF 2 , BaF 2, AIF 3 , LaF 3 , silicon dioxide Si0 2 , and any mixture, alloy or solid solution of mentioned substances as well as organic polymer group comprising of acrylate- and fluoro-polymers. Also organic polymer group comprising of acrylate- and fluoro-polymers are used. Other materials having refractive index not exceeding 1.7 and not mentioned here are possible to use.
- Second nonmetallic layer 6 having refractive index greater than 1.7 is made of materials selected from group comprising sapphire Al 2 0 3 , titanium dioxide Ti0 2 , zinc sulphide ZnS, tantalum pentoxide Ta 2 0 5 , zinc selenide ZnSe, gallium phosphide GaP, gallium nitride GaN, indium tin oxide ITO, niobium pentoxide Nb 2 0 5 , lead molibdate PbMo0 4 boron nitride BN, silicon nitride Si 3 N 4 , aluminum nitride AIN, silicon Si, germanium Ge, selenium Se, semiconductors A 3 B 5 type, semiconductors A 2 B 6 type, semiconductors A 5 B 6 type (arsenic, antimony and bismuth
- Thickness of nonmetallic layer 6 depends on sort of nonmetallic materials of both layers 2 and 6 mainly on its reflective index and on thickness and sort of metal layer 1, and ranges from 10 to 50 nanometers.
- Difference between refractive indices of second and first nonmetallic layers is not less than 0.3. Lower difference than 0.3 increases a visible reflection at "blue” and “red” wavelength ranges and, therefore, a total reflection of visible white light; also undesirable pronounced color of reflected light is generated.
- Substrate (a display or other device outer surface) is made from dielectric material, for example, from glass or polymer.
- Fig.4 an ambient light reflection spectrum of anti-reflective coating according to Fig.3 is depicted. It is clearly seen that a residual reflection of white light does not exceed 0.2% and has a neutral tint (due to a uniform reflection within the visible spectrum range).
- anti-reflective coating an ambient light residual reflection as low as 0.1-0.5% at needed neutral tint. Also anti-reflective coating consists of not greater than three layers which therefore ensures low cost.
Landscapes
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Laminated Bodies (AREA)
- Surface Treatment Of Optical Elements (AREA)
- Optical Elements Other Than Lenses (AREA)
- Optical Filters (AREA)
Abstract
The invention is related to optical coatings and may be used for significant reducing reflection of visible light from an external surface of displays or other devices for optical communication and information processing. Anti-reflective coating in various embodiments consists of two or three layers which include one metal layer of a thickness ranging in various embodiments from 2 to 12 nanometers and one or two nonmetallic layers possessing refractive indices and thicknesses in certain ranges wherein the metal layer is placed either between the nonmetallic layer and a substrate or between the nonmetallic layers.
Description
ANTI-REFLECTIVE COATING
BACKGROUND OF THE INVENTION
(a) Field of the Invention
The invention relates to optical coatings, in particular, to anti-reflective optical coatings and can be used to avoid or largely decrease an ambient light reflection from displays and devices for optical communication and information processing.
(b) Description of the Related Art
A well known anti-reflective coating on a substrate described e.g. in P.W.Baumeister "Optical Coating Technology", pagel-3, fig.1-7 and page 4-11, section 4.3.2, published by SPIE, Washington, USA, 2004 includes one nonmetallic layer having a refractive index less than a substrate refractive index and of quarter-wave optical thickness (the optical thickness of layer is its physical thickness multiplied by the refractive index of the layer). This known anti-reflective coating decreases an ambient light residual reflection to 1.5-2% instead of 4-5% of a bare substrate. A drawback of this one-layer anti-reflective coating is a relatively high residual reflection.
Another well known anti-reflective coating on a substrate described e.g. in P.W.Baumeister "Optical Coating Technology", page 4-12, section 4.3.3.1, published by SPIE, Washington, USA, 2004 includes first nonmetallic layer having a refractive index greater than the substrate refractive index and second nonmetallic layer having a refractive index less than the refractive index of the first nonmetallic layer, wherein the first nonmetallic layer is placed between the second nonmetallic layer and a substrate. This known anti-reflective coating decreases an ambient light residual reflection to 0.5-1% instead of 4-5% of a bare substrate. A drawback of this two-layer anti-reflective coating is a pronounced color of reflected light instead of a needed neutral tint.
Another well known anti-reflective coating on a substrate described, e.g. in P.W.Baumeister "Optical Coating Technology", page 1-14, section 1.3.1.3, published by SPIE, Washington, USA, 2004 includes a set of alternate layers (not less than four layers) with a high and a low reflective indices. This known anti-reflective coating decreases an ambient light residual reflection to 0.1-0.5% instead of 4-5% of a bare substrate. A drawback of this multi-layer anti-reflective coating is a relatively high manufacture cost due to many layer deposition as well as adjustment difficulties.
Heat (infra-red range) reflecting but highly transparent in visible range panel is disclosed in US patent 4,327,967. This panel includes one nonmetallic layer, having a refractive index more than 2, deposited on a glass substrate, gold layer deposited on this nonmetallic layer and other metals thin layer coating gold layer for reflection color neutrality. A drawback of this panel is relatively high reflection (>8%) in visible range.
BRIEF SUMMARY OF THE INVENTION
An object of the invention is an anti-reflective coating supplying on a substrate providing an ambient light residual reflection for visible light as low as 0.1-0.5% at a needed neutral tint.
Another object of the invention while providing low ambient light residual reflection at a needed neutral tint is to minimize amount of layers (not more than three layers) anti-reflective coating consists of, which therefore ensures low cost.
According to the first embodiment of the invention, these objects for visible light are reached with anti- reflective coating on a substrate including one metal layer of a thickness ranging from 2 to 5 nanometers and one nonmetallic layer having reflective index ranging from 1.3 to 1.6 and a thickness ranging from 40 to 80 nanometers, wherein the metal layer is placed between the nonmetallic layer and the substrate.
According to the second embodiment of the invention, these objects for visible light are reached with anti-reflective coating on substrate, including one metal layer of a thickness ranging from 2 to 12 nanometers, first nonmetallic layer having refractive index not exceeding 1.7 and thickness ranges from 30 to 100 nanometers, second nonmetallic layer having refractive index greater than 1.7 and thickness ranges from 10 to 50 nanometers, with difference between refractive indices of second and first nonmetallic layers not less than 0.3, wherein second nonmetallic layer is placed on substrate, the metal layer is placed on second nonmetallic layer, and first nonmetallic layer is placed on the metal layer.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is clarified by drawings which do not completely cover and do not limit the whole scope of claims of the presented technical solution, but only illustrate some embodiments of the anti- reflection coating.
Fig.l shows a first embodiment of anti-reflective coating consisting of one nonmetallic layer having refractive index of not greater than 1.6 and one metal layer of a thickness ranging from 2 to 5 nanometers placed between the nonmetallic layer and substrate.
Fig.2 shows ambient visible light reflection spectrum of anti-reflective coating according to Fig.l.
Fig.3 shows a second embodiment of anti-reflective coating consisting of the first nonmetallic layer having refractive index of not greater than 1.7 and the second nonmetallic layer having refractive index of greater than 1.7 and one metal layer, wherein the second nonmetallic layer is placed on substrate, the metal layer is placed on second nonmetallic layer, first nonmetallic layer is placed on the metal layer.
Fig.4 shows ambient visible light reflection spectrum of anti-reflective coating according to Fig.3.
DETAILED DESCRIPTION OF THE INVENTION
In Fig.l a first embodiment of anti-reflective coating on substrate 3 for visible light including one metal layer 1 of a thickness ranging from 2 to 5 nanometers and one nonmetallic layer 2 having reflective index ranging from 1.3 to 1.6 and a thickness ranging from 40 to 80 nanometers, wherein the metal layer 1 is placed between the nonmetallic layer 2 and a substrate 3 is shown.
Anti-reflective coating works as follows. The ambient white light 4 enters into the anti-reflective coating and is reflected from each interface: "air-nonmetallic layer 2", "nonmetallic layer 2 - metal layer 1", "metal layer 1 - substrate 3". As a result of destructive interference of reflected light a total intensity of reflected light 5 is a very low at certain and properly chosen thickness and refractive index of the nonmetallic layer 1 and optical properties of metal and its thickness.
Metal layer, preferably, is made of the metals chosen from a group comprising: gold Au, silver Ag, aluminum Al, copper Cu, chromium Cr, titanium Ti, nickel Ni, manganese Mn, molybdenum Mo, bismuth Bi, tin Sn, rhodium Rh, platinum Pt, antimony Sb and any alloy or solid solution of mentioned substances. For better adhesion to the substrate 3 and to the mentioned nonmetallic layer 2 the metal layer 1 can include additionally sub-layers that have a thickness of not greater than 1 nanometer and made of materials selected from a group comprising: chromium Cr, titanium Ti, nickel Ni, vanadium V, zirconium Zr, hafnium Hf, niobium Nb, molybdenum Mo, and any mixture, alloy or solid solution of mentioned substances.
Thickness of metal layer 1 depends on which metal is used as well as on thickness and refractive index of nonmetallic layer 2 and ranges from 2 to 5 nanometers. Metal thickness lower than 2 nanometers has no significant influence on a visible reflection vs nonmetallic layer only. Metal thickness higher than 5 nanometers increases a visible reflection at "blue" and "red" wavelength ranges and, therefore, a total reflection of visible white light; also undesirable pronounced color of reflected light is generated.
Known methods are used for a deposition of metal layer 1 on substrate 3: thermal evaporation, evaporation by an electronic beam, deposition by pulverization, by an ion beam, by cathode pulverization, by vapor phase chemical deposition assisted by plasma, etc.
Nonmetallic layer 2 is made of substances selected from group comprising magnesium, calcium, barium, aluminum, lanthanum fluorides MgF2, CaF2, AIF3, LaF3, Si02, and any mixture, alloy, or solid solution of mentioned substances. Also organic polymer group comprising of acrylate- and fluoro-polymers are used. Other materials having refractive index not exceeding 1.6 and not mentioned here are possible to use.
Thickness of nonmetallic layer 2 depends on type of nonmetallic substance, mainly on its refractive index, as well as on thickness and type of metal layer 1 and ranges from 40 to 80 nanometers. Known methods are used for a deposition of nonmetallic layer 2: thermal evaporation, evaporation by an
electronic beam, by pulverization by an ion beam, by cathode pulverization, by vapor phase chemical deposition assisted by plasma, etc. Also wet coating methods are used.
Substrate 3 (a display or other device outer surface) is made from a dielectric material, for example, from glass or polymer.
In Fig.2 an ambient visible light reflection spectrum of anti-reflective coating according to Fig.l is depicted. It is clearly seen that a residual reflection of white light does not exceed 0.35% and has an almost neutral tint (due to a uniform reflection within the visible spectrum range).
In Fig.3 a second embodiment of the invention is shown, This anti-reflective coating on substrate 3 for visible light, including one metal layer 1 of a thickness ranging from 2 to 12 nanometers, first nonmetallic layer 2 having refractive index not exceeding 1.7 and thickness ranges from 30 to 100 nanometers, second nonmetallic layer 6 having refractive index greater than 1.7 and thickness ranges from 10 to 50 nanometers, with difference between refractive indices of second and first nonmetallic layers not less than 0.3, wherein second nonmetallic layer 6 is placed on substrate 3, the metal layer 1 is placed on second nonmetallic layer 6, and first nonmetallic layer 2 is placed on the metal layer 1.
Anti-reflective coating works as follows. The ambient white light 4 enters into the anti-reflective coating and is reflected from each interface: "air-nonmetallic layer 2", "nonmetallic layer 2 - metal layer 1", "metal layer 1 - second nonmetallic layer 6", "second nonmetallic layer 6 - substrate 3". As a result of destructive interference of reflected light the total intensity of reflected light 5 is very low with a proper choice of metal and nonmetallic materials, their thicknesses and refractive indices of nonmetallic layers 2 and 6.
Metal layer, preferably, is made of the materials chosen from group comprising gold Au, silver Ag, aluminum Al, copper Cu, chromium Cr, titanium Ti, nickel Ni, manganese Mn, molybdenum Mo, bismuth Bi, tin Sn, rhodium h, platinum Pt, antimony Sb and any mixtures, alloys, solid solutions or intermetallic compounds of mentioned substances. For better adhesion to the mentioned nonmetallic layer 6 and to the mentioned nonmetallic layer 2 the metal layer 1 can include additionally sub-layers that have a thickness of not greater than 1 nanometer and made of materials selected from group comprising chromium Cr, titanium Ti, nickel Ni, vanadium V, zirconium Zr, hafnium Hf, niobium Nb, molybdenum Mo, and any mixtures, alloys, solid solutions, or intermetallic compounds of mentioned substances.
Thickness of the metal layer 1 depends on sort of metal and on thicknesses and refractive indices of nonmetallic layers 2 and 6, and ranges from 2 to 12 nanometers. Metal thickness lower than 2 nanometers has no significant influence on a visible reflection vs nonmetallic layers only. Metal thickness higher than 12 nanometers increases a visible reflection at "blue" and "red" wavelength ranges and, therefore, a total reflection of visible white light; also undesirable pronounced color of reflected light is generated.
Methods used for a deposition of metal layer 1 on nonmetallic layer 6 are known: magnetron sputtering, thermal evaporation, evaporation by an electronic beam, by pulverization, by an ion beam, by cathode pulverization, by (plasma enhanced) chemical vapor deposition, etc.
Methods used for a deposition of nonmetallic layers 2 and 6 are known: magnetron sputtering, thermal evaporation, electronic beam evaporation, sol-gel, (plasma enhanced) chemical vapor deposition, etc.
Nonmetallic layer 2 having refractive index not exceeding 1.7 is made of materials selected from group comprising magnesium, calcium, barium, aluminum, lanthanum fluorides MgF2, CaF2, BaF2, AIF3, LaF3, silicon dioxide Si02, and any mixture, alloy or solid solution of mentioned substances as well as organic polymer group comprising of acrylate- and fluoro-polymers. Also organic polymer group comprising of acrylate- and fluoro-polymers are used. Other materials having refractive index not exceeding 1.7 and not mentioned here are possible to use.
Thickness of nonmetallic layer 2 depends on sort of nonmetallic material, mainly on its refractive index and thickness and on sort of metal layer 1, and ranges from 30 to 100 nanometers. Second nonmetallic layer 6 having refractive index greater than 1.7 is made of materials selected from group comprising sapphire Al203, titanium dioxide Ti02, zinc sulphide ZnS, tantalum pentoxide Ta205, zinc selenide ZnSe, gallium phosphide GaP, gallium nitride GaN, indium tin oxide ITO, niobium pentoxide Nb205, lead molibdate PbMo04 boron nitride BN, silicon nitride Si3N4, aluminum nitride AIN, silicon Si, germanium Ge, selenium Se, semiconductors A3B5 type, semiconductors A2B6 type, semiconductors A5B6 type (arsenic, antimony and bismuth chalcogenides) and any mixture or solid solution of mentioned substances.
Thickness of nonmetallic layer 6 depends on sort of nonmetallic materials of both layers 2 and 6 mainly on its reflective index and on thickness and sort of metal layer 1, and ranges from 10 to 50 nanometers.
Difference between refractive indices of second and first nonmetallic layers is not less than 0.3. Lower difference than 0.3 increases a visible reflection at "blue" and "red" wavelength ranges and, therefore, a total reflection of visible white light; also undesirable pronounced color of reflected light is generated.
Substrate (a display or other device outer surface) is made from dielectric material, for example, from glass or polymer.
In Fig.4 an ambient light reflection spectrum of anti-reflective coating according to Fig.3 is depicted. It is clearly seen that a residual reflection of white light does not exceed 0.2% and has a neutral tint (due to a uniform reflection within the visible spectrum range).
The technical result assured by aggregated attributes of the anti-reflective coating described here is: an ambient light residual reflection as low as 0.1-0.5% at needed neutral tint. Also anti-reflective coating consists of not greater than three layers which therefore ensures low cost.
This result is achieved by optimum balance of thicknesses of the nonmetallic layers, their refractive indexes, and the thickness of the metal layer.
Claims
1. Anti-reflective coating on substrate for visible light including: one metal layer of a thickness ranging from 2 to 5 nanometers and
one nonmetallic layer having reflective index ranging from 1.3 to 1.6 and a thickness ranging from 40 to 80 nanometers, wherein the metal layer is placed between the nonmetallic layer and a substrate.
2. Anti-reflective coating according to Claim 1, wherein the metal layer is made of materials selected from group comprising gold Au, silver Ag, aluminum Al, chromium Cr, titanium Ti, nickel Ni, manganese Mn, molybdenum Mo, bismuth Bi, tin Sn and any mixtures, alloys, solid solution or intermetallic compounds of mentioned substances.
3. Anti-reflective coating according to Claim 2, wherein the metal layer includes additionally sublayers of total thickness not exceeding 1 nanometer and made of metals selected from group comprising chromium Cr, titanium Ti, nickel Ni, vanadium V, zirconium Zr, hafnium Hf, niobium Nb, molybdenum Mo, and any mixture, alloy or solid solution of mentioned substances.
4. Anti-reflective coating according to Claim 1, wherein the mentioned nonmetallic layer is made of materials selected from group comprising MgF2, CaF2, BaF2, Si02, AIF2, LaF3 and any mixture or solid solution of mentioned substances, as well as organic polymer group comprising of acrylate- and fluoro- polymers.
5. Anti-reflective coating on substrate for visible light, including: one metal layer of a thickness ranging from 2 to 12 nanometers, and first nonmetallic layer having refractive index not exceeding 1.7 and thickness ranges from 30 to 100 nanometers, and
second nonmetallic layer having refractive index greater than 1.7 and thickness ranges from 10 to 50 nanometers with difference between refractive indices of second and first nonmetallic layers not less than 0.3,
wherein second nonmetallic layer is placed on substrate, the metal layer is placed on second nonmetallic layer, and first nonmetallic layer is placed on the metal layer.
6. Anti-reflective coating according to Claim 5, wherein the metal layer is made of materials selected from group comprising gold Au, silver Ag, aluminum Al, chromium Cr, titanium Ti, nickel Ni, manganese Mn, molybdenum Mo, bismuth Bi, tin Sn and any mixtures, alloys, solid solution or intermetallic compounds of mentioned substances.
7. Anti-reflective coating according to Claim 6, wherein the metal layer includes additionally sublayers of total thickness not exceeding 1 nanometer and made of metals selected from group comprising chromium Cr, titanium Ti, nickel Ni, vanadium V, zirconium Zr, hafnium Hf, niobium Nb, molybdenum Mo, and any mixture, alloy or solid solution of mentioned substances.
8. Anti-reflective coating according to Claim 5, wherein the first nonmetallic layer is made of materials selected from group comprising MgF2, CaF2, BaF2, Si02, AIF3, LaF3 and any mixture or solid solution of mentioned substances, as well as organic polymer group comprising of acrylate- and fluoro- polymers.
9. Anti-reflective coating according to Claim 5, wherein the mentioned second nonmetallic layer is made of materials selected from group comprising titanium dioxide Ti02, zinc sulphide ZnS, tantalum pentoxide Ta205, zinc selenide ZnSe, gallium phosphide GaP, indium tin oxide ITO, gallium nitride GaN, niobium pentoxide Nb205, lead molibdate PbMo04j boron nitride BN, silicon nitride Si3N4, aluminum nitride AIN, silicon Si, germanium Ge, selenium Se, semiconductors A3B5 type, semiconductors A2B6 type, semiconductors A5B6 type (arsenic, antimony and bismuth chalcogenides) and any mixture or solid solution of mentioned substances.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201315089207A | 2013-03-01 | 2013-03-01 | |
PCT/US2014/018578 WO2014134124A1 (en) | 2013-03-01 | 2014-02-26 | Anti-reflective coating |
Publications (1)
Publication Number | Publication Date |
---|---|
EP2961602A1 true EP2961602A1 (en) | 2016-01-06 |
Family
ID=51428749
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP14756263.1A Withdrawn EP2961602A1 (en) | 2013-03-01 | 2014-02-26 | Anti-reflective coating |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP2961602A1 (en) |
JP (1) | JP2016528516A (en) |
KR (1) | KR20150126885A (en) |
CN (1) | CN105163939B (en) |
AU (1) | AU2014223560A1 (en) |
WO (1) | WO2014134124A1 (en) |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR102427151B1 (en) * | 2015-08-31 | 2022-07-28 | 엘지디스플레이 주식회사 | A display device |
KR102478211B1 (en) * | 2016-04-08 | 2022-12-20 | 필킹톤 그룹 리미티드 | Light emitting diode display and insulated glass unit including the same |
CN106067652B (en) * | 2016-07-29 | 2022-03-08 | 杭州科汀光学技术有限公司 | Dual-wavelength antireflection film for excimer laser and optical film thickness monitoring system |
FR3054892A1 (en) * | 2016-08-02 | 2018-02-09 | Saint Gobain | SUBSTRATE PROVIDED WITH A STACK WITH THERMAL PROPERTIES COMPRISING AT LEAST ONE LAYER COMPRISING ZIRCONIUM ENRICHED SILICON ZIRCONIUM NITRIDE, USE THEREOF AND MANUFACTURE THEREOF |
CN106291908B (en) * | 2016-10-18 | 2021-05-11 | 中国科学院国家天文台南京天文光学技术研究所 | Gold-enhanced reflecting film system for primary mirror of large astronomical telescope and preparation method thereof |
JP7117081B2 (en) * | 2017-05-12 | 2022-08-12 | Hoya株式会社 | Dust-proof lens and manufacturing method thereof |
KR102395098B1 (en) | 2017-06-30 | 2022-05-06 | 삼성디스플레이 주식회사 | Display device and fabricating method of the same |
CN108196334A (en) * | 2018-01-05 | 2018-06-22 | 京东方科技集团股份有限公司 | A kind of polaroid and preparation method thereof, display device |
KR20210072864A (en) | 2019-12-09 | 2021-06-18 | 현대자동차주식회사 | Anti-reflective lens for infrared ray |
CN113320248A (en) * | 2021-07-04 | 2021-08-31 | 北京载诚科技有限公司 | Display film and display module |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5744227A (en) * | 1995-04-03 | 1998-04-28 | Southwall Technologies Inc. | Antireflective coatings comprising a lubricating layer having a specific surface energy |
US6764580B2 (en) * | 2001-11-15 | 2004-07-20 | Chungwa Picture Tubes, Ltd. | Application of multi-layer antistatic/antireflective coating to video display screen by sputtering |
US7199046B2 (en) * | 2003-11-14 | 2007-04-03 | Tokyo Electron Ltd. | Structure comprising tunable anti-reflective coating and method of forming thereof |
US7994600B2 (en) * | 2005-12-21 | 2011-08-09 | Texas Instruments Incorporated | Antireflective coating |
US8355418B2 (en) * | 2009-09-17 | 2013-01-15 | Soraa, Inc. | Growth structures and method for forming laser diodes on {20-21} or off cut gallium and nitrogen containing substrates |
-
2014
- 2014-02-26 JP JP2015560272A patent/JP2016528516A/en active Pending
- 2014-02-26 KR KR1020157027026A patent/KR20150126885A/en not_active Application Discontinuation
- 2014-02-26 WO PCT/US2014/018578 patent/WO2014134124A1/en active Application Filing
- 2014-02-26 AU AU2014223560A patent/AU2014223560A1/en not_active Abandoned
- 2014-02-26 CN CN201480024025.3A patent/CN105163939B/en not_active Expired - Fee Related
- 2014-02-26 EP EP14756263.1A patent/EP2961602A1/en not_active Withdrawn
Non-Patent Citations (1)
Title |
---|
See references of WO2014134124A1 * |
Also Published As
Publication number | Publication date |
---|---|
CN105163939B (en) | 2017-09-29 |
WO2014134124A1 (en) | 2014-09-04 |
JP2016528516A (en) | 2016-09-15 |
KR20150126885A (en) | 2015-11-13 |
AU2014223560A1 (en) | 2015-10-29 |
CN105163939A (en) | 2015-12-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2014134124A1 (en) | Anti-reflective coating | |
TWI531821B (en) | Interference filter, optical module, and analyzing device | |
US11422290B2 (en) | Antireflection film, optical element, and optical system | |
US7133197B2 (en) | Metal-dielectric coating for image sensor lids | |
JP2004152727A (en) | Transparent conductive film | |
RU2578071C1 (en) | Ir-reflecting and transparent system of layers having colour stability, and method of making same manufacture, glass block | |
EP2962136A1 (en) | Reflective color filter and color display device | |
JP2009083183A (en) | Optical membrane laminate | |
US11194078B2 (en) | Antireflection film having silver-containing layer and fluorocarbon layer, method for producing antireflection film, optical element, and optical system | |
CN102375173A (en) | Interference filter, optical module, and analysis device | |
US11747520B2 (en) | Optical thin film having metal layer containing silver and high standard electrode potential metal | |
JP2017030348A (en) | Laminate film and heat ray reflection material | |
US10641927B2 (en) | Optical thin film, optical element, optical system, and method for producing optical thin film | |
JP6302688B2 (en) | High reflection film, substrate with high reflection film, and method of manufacturing high reflection film | |
US20140248507A1 (en) | Anti-reflective coating | |
JP2004334012A (en) | Antireflection film and optical filter | |
JP6727454B2 (en) | Antireflection film, optical element and optical system | |
JP3221349B2 (en) | Heat ray reflective film | |
WO2015053371A1 (en) | Transparent conductor | |
JPH1130705A (en) | Spectacle plastic lens with reflection preventive film | |
KR20220042931A (en) | Transpatent substrate having multilayer thin film coating | |
JPH052173A (en) | Liquid crystal display device | |
WO2018135124A1 (en) | Csp mirror and method for producing glass substrate with film for csp mirrors | |
TW202043841A (en) | Liquid lenses and liquid lens articles with low reflectivity electrode structures | |
CN114114743A (en) | LCOS display device and manufacturing method thereof |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20150930 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
AX | Request for extension of the european patent |
Extension state: BA ME |
|
DAX | Request for extension of the european patent (deleted) | ||
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 20160901 |