Spectacle lens with color-neutral anti-reflection coating and method of making the same

• US 8,425,035 B2
• Filed: 03/08/2011
• Issued: 04/23/2013
• Est. Priority Date: 09/08/2008
• Status: Active Grant

• Current Assignee: Carl Zeiss Vision GMBH (Carl-Zeiss-Stiftung)
• Original Assignee: Carl Zeiss Vision GMBH (Carl-Zeiss-Stiftung)
• Inventors: von Blanckenhagen, Bernhard
• Primary Examiner(s): GREECE, JAMES R
• Application Number:
  US13/043,280
• Publication Number:
  US 20110228214A1
• Time in Patent Office: 777 Days
• Field of Search: 351/160.R, 351/160.H, 351/159, 351/161, 351/162, 351/163, 351/159.01, 351/159.57, 3511596-15965
• US Class Current: 351/159.6
• CPC Class Codes: B29D 11/00923 on lens surfaces for colouring or tinting printing or marking in general B41M
• CPC Class Codes: G02B 1/115 Multilayers

Abstract

A spectacle lens (2) has an antireflective coating (1). The antireflective coating (1) produces a residual reflection appearing color-neutral not only under illumination with a natural daylight spectrum, but also under an illumination with an illumination spectrum deviating from the natural daylight spectrum. A method for making a spectacle lens (2) having an antireflective coating (1) is described in which an optical lens (2a) is provided and a layer sequence of layers (3, 4, 5, 6, 7, 8, 9) with alternately high and low refractive material forming the antireflective coating (1) is applied to the optical lens. The antireflective coating (1) is applied with the proviso that the antireflective coating (1) produces a residual reflection appearing color-neutral not only under illumination with a natural daylight spectrum, but also under an illumination with an illumination spectrum deviating from the natural daylight spectrum.

Claims

1. A spectacle lens comprising:

a spectacle lens body defining a surface;

an antireflection coat me applied to said surface to generate a color neutral appearing residual reflectance when illuminated with a natural daylight spectrum;

said antireflection coating including an interference layer system being configured to generate a color neutral appearing residual reflectance when illuminated with an illumination spectrum which departs from said natural daylight spectrum; and

,

said interference layer system including a plurality of layers wherein each two mutually adjacent ones of said layers are made of respective materials having indices of refraction different from one another;

wherein said illumination spectrum is a spectrum in one of the standard color temperature ranges;

warm white, neutral white, or daylight;

or, said illumination spectrum is one of the CIE standard spectra A and CIE standard spectra C;

said color neutral appearing residual reflectance having a color coordinate a* of the L*a*b*-color coordinate system lying in the range of [−

1.5]<

a*<

[1.5];

said color neutral appearing residual reflectance having a color coordinate b* of the L*a*b*-color coordinate system lying in the range of [−

1.5]<

b*<

[1.5]; and

,

said color neutral appearing residual reflectance having a color coordinate L* of the L*a*b*-color coordinate system lying in the range of [0]<

L*<

[7].

2. The spectacle lens of claim 1, wherein:

said color neutral appearing residual, reflectance has a color coordinate a* of the L*a*b*-color coordinate system lying in the range of [−

1.3]<

a*<

[1.1].

3. The spectacle lens of claim 1, wherein:

said color neutral appearing residual reflectance has a color coordinate b* of the L*a*b*-color coordinate system lying in the range of [−

1.4]<

b*<

[1.2].

4. The spectacle lens of claim 1, wherein;

said color neutral appearing residual reflectance has a color coordinate L* of the L*a*b*-color coordinate system lying in the range of [4]<

L*<

[7].

5. The spectacle lens of claim 1, wherein said interference layer system is configured from layers which are transparent in the visible spectral region;

and, said layers have an optical thickness which is less than the wavelength of the visible light.

6. The spectacle lens of claim 5, wherein said interference layer system has a layer sequence of materials having alternatingly high and low refractive indexes.

10. The spectacle lens of claim 1 further comprising a scratch resistant layer disposed under said antireflection coating.

12. The spectacle lens of claim 10, wherein said scratch resistant layer has a thickness (d_x) between 2 and 4 micrometers.

7. A spectacle lens comprising:

an antireflection coating generating a color neutral appearing residual reflectance when illuminated with a natural daylight spectrum;

said antireflection coating being configured also generate a color neutral appearing residual reflectance when illuminated with an illumination spectrum which departs from said natural daylight spectrum;

when said antireflection coating rather comprises an interference layer system, wherein;

said interference layer system is configured from layers which are transparent in the visible spectral region;

said layers have an optical thickness which is less than the wavelength taken of the range of visible light; and

,

said interference layer system includes at least one of a hydrophohic and an oleophobic surface layer having a surface energy of less than 20 mN/m.

8. A spectacle lens comprising:

a spectacle lens body defining a surface;

an antireflection coating applied to said surface to generate a color neutral a eating residual reflectance when illuminated with a natural daylight spectrum;

said antireflection coating including an interference layer system being configured to generate a color neutral appearing residual reflectance when illuminated with an illumination spectrum which departs from said natural daylight spectrum;

said interference layer system including a plurality of layers wherein each two mutually adjacent ones of said layers are made of respective materials having indices of refraction different from one another;

said interference layer system being configured from layers which are transparent in the visible spectral region; and

, said layers having an optical thickness which is less than the wavelength of the visible light;

said spectacle lens having a spectacle lens substrate and wherein;

said interference layer system has the following layer sequence starting from said spectacle lens substrate;

a) a first layer Of hafnium oxide;

b) a second layer of silicon dioxide;

c) a third layer of hafnium oxide;

d) a fourth layer of niobium pentoxide;

e) a fifth layer of hafnium oxide;

f) a sixth layer of silicon oxide; and

,

g) a seventh layer of an easy-to-clean coating.

9. The spectacle lens of claim 8, wherein:

said first layer has a layer thickness (d₃) of 16 nm;

said second layer has a layer thickness (d₄) of 36 nm;

said third layer has a layer thickness (d₅) of 77 nm;

said fourth layer has a layer thickness (d₆) of 88 nm;

said fifth layer has a layer thickness (d₇) of 31 nm;

said sixth layer has a layer thickness (d₈) of 65 nm; and

,

said seventh layer has a layer thickness (d₉) of 5 nm.

11. A spectacle lens comprising:

a spectacle lens body defining a surface;

an antireflection coating applied to said surface to generate a color neutral appearing residual reflectance when illuminated with a natural daylight spectrum;

said antireflection coating including an interference layer system being configured to generate a color neutral appearing residual reflectance When illuminated with an illumination spectrum which departs from said natural daylight spectrum;

said interference layer system including a plurality of layers wherein each two mutually adjacent ones of said layers are made of respective materials having indices of refraction different from one another;

a scratch resistant layer disposed under said antireflection coating;

a spectacle lens substrate having a refractive index (n_2a); and

, wherein;

said scratch resistant layer has a refractive index (n_x) which differs from said refractive index (n_2a)of said spectacle lens substrate by up to 0.5.

13. A method of making a spectacle lens having an antireflection coating, said method comprising the steps of:

providing an optical lens

applying a layer sequence configured to form an antireflection coating onto said spectacle lens, said layer sequence including a plurality of layers wherein each two mutually adjacent ones of said layers are made of respective materials having indices of refraction different from one another;

wherein;

the application of said antireflection coating is accompanied by a first requirement that said antireflection coating generate a color-neutral appearing residual reflectance when illuminated by natural daylight spectrum; and

,

the application of said antireflection coating is accompanied by a second requirement that said antireflection coating generate a color-neutral appearing residual reflectance when illuminated by an illumination spectrum deviating from said natural daylight spectrum;

said illumination spectrum is a spectrum in one of the standard color temperature ranges;

warm white, neutral white, or daylight;

or, said illumination spectrum is one of the CIE standard spectra A and CIE standard spectra C;

said color neutral appearing residual reflectance having a color coordinate a* of the L*a*b*-color coordinate living system in the range of [−

1.5]<

a*<

[1.5];

said color neutral appearing residual reflectance having a color coordinate b* of the L*a*b*-color coordinate system living in the range of [−

1.5]<

b*<

[1.5]; and

,

said color neutral appearing residual reflectance having a color coordinate L* of the L*a*b*-color coordinate system lying in the range of [0]<

L*<

[7].

14. The Method of claim 13, comprising the further step of applying a scratch resistant layer.

15. The method of claim 13, wherein a common color target value is pregiven for the reflectance of the antireflection coating occurring because of natural daylight and for the reflectance of the antireflection coating occurring because of the deviating illumination;

and, one or several thicknesses and/or materials of the layers, which form the antireflection coating, are varied until the deviation of a computed color value for the natural daylight spectrum and the deviation of a computed color value for the deviating illumination spectrum drop below pregiven threshold values; and

, the threshold values are so selected that the color impression appears neutral under both illumination conditions.

16. A spectacle lens comprising:

a spectacle lens body defining a surface;

an antireflection coating applied to said surface to generate a color neutral appearing residual reflectance when illuminated with a natural daylight spectrum;

said antireflection coating including an interference layer system being configured to generate a color neutral appearing residual reflectance when illuminated with an illumination spectrum which departs from said natural daylight spectrum; and

,

said interference layer system including a first layer closest to said surface made of a material having a low refractive index and a next layer made of a material having a refractive index greater than said first layer and a third layer having a refractive index lying in a range between the refractive indices of said first and second layer;

wherein said illumination spectrum is a spectrum in one of the standard color temperature ranges;

warm white, neutral white, or daylight;

or, said illumination spectrum is one of the CIE standard spectra A and CIE standard spectra C;

said color neutral appearing residual reflectance having a color coordinate a* of the L*a*b*-color coordinate system lying in the range of [−

1.5]<

a*<

[1.5];

said color neutral appearing residual reflectance having a color coordinate b* of the L*a*b*-color coordinate system lying in the range of [−

1.5]<

b*<

[1.5]; and

,

said color neutral appearing residual reflectance having a color coordinate L* of the L*a*b*-color coordinate lying in the range of [0]<

L*<

[7].

17. A spectacle lens comprising:

a spectacle lens body defining a surface;

a hard lacquer coating applied to said surface;

an antireflection coating applied on top of said hard lacquer coating to generate a color neutral appearing residual reflectance when illuminated with a natural daylight spectrum;

said antireflection coating including an interference layer system being configured to generate a color neutral appearing residual reflectance when illuminated with an illumination spectrum which departs from said natural daylight spectrum; and

,

said interference layer system including a plurality of layers wherein each two mutually adjacent ones of said layers are made of respective materials having indices of refraction different from one another;

wherein said illumination spectrum is spectrum in one of the standard color temperature ranges;

warm white, neutral white, or daylight;

or, said illumination spectrum is one of the CIE standard spectra A and CIE standard spectra C;

said color neutral appearing residual reflectance having color coordinate a* of the L*a*b*-color coordinate system lying in the range of [−

1.5]<

a*<

[1.5];

said color neutral appearing residual reflectance having a color coordinate b* of the L*a*b*-color coordinate system lying in the range of [−

1.5]<

b*<

[1.5]; and

said color neutral appearing residual reflectance having a Color coordinate L* of the L*a*b*-color coordinate system lying in the range of [0]<

L*<

[7].

18. A spectacle lens comprising:

an antireflection coating generating a color neutral appearing residual reflectance when illuminated with a natural daylight spectrum;

said antireflection coating being configured to also generate a color neutral appearing residual reflectance when illuminated with an illumination spectrum which departs from said natural daylight spectrum;

wherein said antireflection coating further comprises an interference layer system, wherein;

said interference layer system is configured from layers which are transparent in the visible spectral region;

said layers have an optical thickness which is less than the wavelength taken of the range of visible light; and

,

said interference layer system includes an outer layer defined by a hydrophobic or an oleophobic layer having a surface energy of less than 20 mN/m.

19. A method of making a spectacle lens having an antireflection coating, said method comprising the steps of:

providing an optical lens defining a surface;

applying a layer sequence configured to form an antireflection coating onto said spectacle lens, said layer sequence including a first layer closest to said surface made of a material having a low refractive index and a next layer made of a material having a refractive index greater than said first layer and a third Layer having a refractive index lying in a range between the refractive indices of said first and second layers;

wherein;

the application of said antireflection coating is accompanied by a first requirement that said antireflection coating generate a color-neutral appearing residual reflectance when illuminated by a natural daylight spectrum; and

,

the application of said anti reflection coating is accompanied by a second requirement that said antireflection coating generate a color-neutral appearing residual reflectance when illuminated by an illumination spectrum deviating from said natural daylight spectrum;

said illumination spectrum is a spectrum in one of the standard color temperature ranges;

warm white, neutral white, or daylight;

or, said illumination spectrum is one of the CIE standard spectra A and CIE standard spectra C;

said color neutral appearing residual reflectance having a color coordinate a* of the L*a*b*-color coordinate system lying in the range of [−

1.5]<

a*<

[1.5];

said color neutral appearing residual reflectance having a color coordinate b* of the L*a*b*-color coordinate system lying in the range of [−

1.5]<

b*<

[1.5]; and

,

said color neutral appearing residual reflectance having a color coordinate L* of the L*a*b*-color coordinate system lying in the range of [0]<

L*<

[7].