Method of producing anti-reflection film
AssigneeBridgestone Corporation
InventorsMitsuhiro Nishida, Yukihiro Kusano, Nobuko Kato
Life of this patent
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Abstract
A method of producing an anti-reflection film includes forming a first layer on a transparent substrate, forming a second layer on the first layer, and forming the third layer on the second layer. When an optical admittance Y at a surface of the second layer is represented by, Y = H E = ( x + iy ) where i is the imaginary number unit, thicknesses and reflective indexes of the substrate, first layer, second layer, and third layer are selected so that x and y satisfy the following formula, 0.9x{(n2−n02)/2n0}2<{x−(n2+n02)/2n0}2+y2<1.1x{(n2−n02)/2n0}2 where n is a refractive index of the third layer and n0 is a refractive index of an outer region at an outside of the anti-reflection film.
Claims13
A method of producing an anti-reflection film, comprising:
- selecting a first material having a-reflective index of n1,
- coating the first material on a transparent substrate having a reflective index of ns to form a first layer having a thickness of d1,
- selecting a second material having a reflective index of n2,
- coating the second material on the first layer to form a second layer having a thickness of d2 so that an optical admittance Y at a surface of the second layer opposite to the first layer is represented by,
- Y
- =
- H
- E
- =
- (
- x
- +
- iy
- )
- where i is the imaginary number unit,
- [
- E
- H
- ]
- =
- [
- cos
-
-
- δ
- 2
- (
- i
- /
- n
- 2
- )
-
-
- sin
-
-
- δ
- 2
- i
-
-
- n
- 2
-
-
- sin
-
-
- δ
- 2
- cos
-
-
- δ
- 2
- ]
-
- [
- cos
-
-
- δ
- 1
- (
- i
- /
- n
- 1
- )
-
- sin
-
-
- δ
- 1
- i
-
-
- n
- 1
-
- sin
-
-
- δ
- 1
- cos
-
-
- δ
- 1
- ]
-
- [
- 1
- n
- s
- ]
- δ1=2πn1d1/λ0
- δ2=2πn2d2/λ0
- where λ0 is a wavelength of incident light in vacuum,
- selecting a third material having a reflective index of n3, and
- coating the third material on the second layer to form a third layer having a thickness of d3,
- wherein said reflective index of the transparent substrate, the reflective index and the thickness of the first layer, the reflective index and the thickness of the second layer, and the reflective index of the third layer are selected so that x and y satisfy the following formula,
- 0.9x{(n32−n02)/2n0}2<{x−(n32+n02)/2n0}2+y2<1.1x{(n32−n02)/2n0}2
- where n0 is a refractive index of an outer region at an outside of the anti-reflection film.
Dependencies are inferred from the claim text.