Ophthalmic article in particular for sunglasses
The invention relates to an ophthalmic article ( 1 ), in particular for sunglasses, comprising at least one substrate ( 9 ) and a photochromic filter compound ( 15 ), the ophthalmic article ( 1 ) having a first transmission spectrum in an activated state of the photochromic filter compound ( 15 ) and a second transmission spectrum in a deactivated state of the photochromic filter compound, such that: ⋅—the first and the second transmission spectra at wavelengths lower than 380 nm is lower than 1%, ⋅—the first and the second transmission spectra have a relative first maximum between 460 nm and 510 nm, ⋅—the first and the second transmission spectrum have a relative first minimum between 560 nm and 610 nm, and where ⋅—T v activated is the luminous transmittance according to ISO_13666 in the activated state of the photochromic filter compound. ⋅—T v deactivated is the luminous transmittance according to ISO_13666 in the deactivated state of the photochromic filter compound. ⋅The lens has a reduced transmission in the blue between 400 and 450 nm and a reduced transmission around 585 nm. The lens provides a good contrast and reduces glare. T v deactivated T v activated > 2.5 T v activated T ν deactivated
1 . An ophthalmic article comprising at least one substrate and a photochromic filter compound, the ophthalmic article having a first transmission spectrum in an activated state of the photochromic filter compound and a second transmission spectrum in a deactivated state of the photochromic filter compound, wherein:
the first and the second transmission spectra at wavelengths lower than 380 nm is lower than 1%;
the first and the second transmission spectra have a relative first maximum (MAX_1_activated, MAX 1_deactivated) between 460 nm and 510 nm;
the first and the second transmission spectrum have a relative first minimum (MIN_1_activated, MIN_1_deactivated) between 560 nm and 610 nm; and
T
v
deactivated
T
v
activated
>
2.5
wherein the first relative maximum (MAX_1_activated) of the first transmission spectrum in the activated state of the photochromic filter compound presents a transmission comprised between 40% and 55%; and
wherein:
T
v
activated
is the luminous transmittance according to ISO_13666 between 380 nm and 780 nm in the activated state of the photochromic filter compound; and
T
v
deactivated
is the luminous transmittance according to ISO_13666 between 380 nm and 780 nm in the deactivated state of the photochromic filter compound.
2 . The ophthalmic article according to claim 1 , wherein:
3.1
>
T
v
deactivated
T
v
activated
>
2.6
.
3 . The ophthalmic article according to claim 1 , wherein the luminous transmittance
T
v
activated
according to ISO_13666 is lower than 30% in the activated state of the photochromic filter compound and the luminous transmittance
T
v
deactivated
according to ISO_13666 is higher than 65% in the deactivated state of the photochromic filter compound.
4 . The ophthalmic article according to claim 1 , wherein in the activated state of the photochromic filter compound, the transmission of the first spectrum is less than 30%, between 425 nm and 450 nm.
5 . The ophthalmic article according to claim 1 , wherein in the activated state of the photochromic filter compound, the transmission of the first spectrum shows a variation of less than 2% between 430 nm and 450 nm.
6 . The ophthalmic article according to claim 1 , wherein said first maxima (MAX_1_activated, MAX_1_deactivated) of the first and the second spectra are distant less than 5 nm from each other and said first minima (MIN_1_activated, MIN_1_deactivated) of the first and the second spectrum and are distant less than 5 nm from each other.
7 . The ophthalmic article according to claim 1 , wherein
T
MAX
1
deactivated
T
MAX
1
activated
>
1.5
wherein:
T
MAX
1
activated
is the transmittance at the wavelength of the first maximum (MAX_1_activated) in the activated state of the photochromic filter compound; and
T
MAX
1
deactivated
is the transmittance at the wavelength of the first maximum (MAX_1_deactivated) in the deactivated state of the photochromic filter compound.
8 . The ophthalmic article according to claim 1 , wherein
T
MIN
1
deactivated
T
MIN
1
activated
>
3.5
wherein:
T
MIN
1
activated
is the transmittance at the wavelength of the first minimum (MIN_1_activated) in the activated state of the photochromic filter compound; and
T
MIN
1
deactivated
is the transmittance at the wavelength of the first minimum (MIN_1_deactivated) in the deactivated state of the photochromic filter compound.
9 . The ophthalmic article according to claim 1 , wherein the transmission between 435 nm and 530 nm is equal or higher than 70%, for the second transmission spectrum in the deactivated state of the photochromic filter compound.
10 . The ophthalmic article according to claim 1 , wherein the first relative minimum (MIN_1_deactivated) has a transmission of 35%, or less for the second transmission spectrum in the deactivated state of the photochromic filter compound.
11 . The ophthalmic article according to claim 1 , wherein the transmission at a wavelength equal or superior to 610 nm is equal or higher than 75%, for the second transmission spectrum in the deactivated state of the photochromic filter compound.
12 . The ophthalmic article according to claim 1 , wherein the second transmission spectrum in the deactivated state of the photochromic filter compound presents a second relative minimum (MIN_2_deactivated) at 536 nm+/−3 nm with a transmission comprised between 65% and 80%.
13 . The ophthalmic article according to claim 1 , wherein the second transmission spectrum in the deactivated state of the photochromic filter compound presents a second relative maximum (MAX_2_deactivated) at 547 nm+/−3 nm with a transmission comprised between 70% and 85%.
14 . The ophthalmic article according to claim 1 , further comprising a film deposited on the substrate and comprising the photochromic filter compound.
15 . The ophthalmic article according to claim 1 , wherein the photochromic filter compound is integrated in the matrix of the substrate.
16 . The ophthalmic article according to claim 1 , wherein the photochromic filter compound comprises a mix of solvent dyes, narrow band dyes and photochromic dyes.
17 . The ophthalmic article according to claim 1 , wherein the at least one substrate comprises one or more colorants and/or pigments, said colorants and/or pigments of all the substrates interacting together with the photochromic filter compound in order to absorb the light passing through the ophthalmic article for providing the first transmission spectrum in the activated state of the photochromic filter compound and the second transmission spectrum in the deactivated state of the photochromic filter compound.
18 . The ophthalmic article according to claim 1 , wherein the first relative minimum (MIN_1_activated) has a transmission of 10% or less for the first transmission spectrum in the activated state of the photochromic filter compound.
19 . Sunglasses comprising an ophthalmic article according to claim 1 .